The deflection of an electron beam by the action of an electrostatic field that has a component perpendicular to the...

A camera lens, used in macrophotography, that is designed and corrected to produce optimum definition of a nearby object...

Any instrument or system carried by a balloon to the upper atmosphere to measure and record atmospheric information, such as...

A piece of uniform birefringent material placed at a 45° angle to the plane of polarization in a polarizing microscope...

Histochemical staining is a laboratory technique used in biology and medicine to visualize specific chemical components...

An optical assembly refers to a collection of optical components that are carefully arranged and aligned to perform a...

A single long gate electrode that transfers the line of charge packets to the transport shift register in a charge-coupled...

The tendency to adjust an instrument such as a microscope so that the viewed image appears much closer than infinity.

In a gas, the temporary drop in density caused by contact with a sound wave.

The physical area containing an assembly of computer graphics equipment for presenting generated images and allowing...

A filter, partially opaque to near-ultraviolet, visible and infrared radiation, that may be made by exposing and processing...

The monochromatic transparency effect produced by the immersion of a finely powdered substance (e.g., glass or quartz) into...

Optical phase distortion refers to a phenomenon where the phase of an optical wavefront is altered as it propagates through...

Brightfield refers to a type of microscopy and imaging technique in which the specimen is illuminated with a white light...

A lens blank is a piece of optical material in a raw, unfinished state, typically in the form of a disk or block, from which...

The elongation of a transmitted data pulse through a fiber optic due to the chromatic dispersion of the fiber material.

An additive color mixture that appears to have no hue.

A defect in an optical system that prevents rays from reaching their intended destination; it can be caused by an undersized...

A product of the area of a light beam (normal to its direction of propagation) and the solid angle that the beam includes;...

A laser-induced scar on experimental bare glass surfaces usually attributable to threshold damage and indicative of isolated...

A device used to accelerate the electrons in a free-electron laser by channeling microwave energy into waveguide cavity...

A binary code with two information states (1 and 0) and no neutral state between bits.

A system that uses both reflection and refraction to achieve its focal power. While the relative powers of the lenses and...

A lamp with a quartz envelope that transmits radiation generally rich in the ultraviolet.

The Weissenberg method, named after the German physicist Karl Weissenberg, is a technique used in x-ray crystallography for...

Three proportional coefficients labeled Am, Bmn, and Bnm, that respectively characterize the rate of spontaneous emission,...

The luminance portion of a composite video signal, i.e., the portion of the signal that corresponds to the brightness of the...

A system for automatic industrial process control or measurement, consisting of an optical module for image acquisition, a...

A bundle of filaments of optical glass or other transparent materials that transmit only light, not optical images. The...

The measured width of the field of view at any distance.

A spectrograph in which the flux density transmitted through the entrance aperture is regulated by an optical wedge or...

A method of cleaning and drying coated optical components. The cooled parts are placed in a container above a boiling...

The process of creating a large, panoramic image by aligning and joining a set of smaller images. Image processing is used...

A device similar to distributed feedback lasers in construction and operation, but in which the period grating that produces...

Laser-induced fluorescence (LIF) is a spectroscopic technique that involves using a laser to excite molecules or atoms,...

That property of a substance that determines that all components of volume are the same in composition and optical...

A method that produces low-loss optical fibers. A glass tube rotates while reactants pass through the tube and heat is...

With respect to the effect of crystals on lightwaves, the family of curves having constant direction of polarization.

A flaw deliberately introduced into an optical fiber to prepare it for cleaving.

A small defocused Galilean telescope mounted in a hole in a door. Viewed from inside through the positive lens, a wide-angle...

The electron emission from a substance or instrument whose surface has been bombarded by a suitable amount of radiation.

The transparent fluid that fills the portion of the eye between the eye lens and the retina (the posterior chamber).

Nonimage-forming light, concentrated or diffuse, that is transmitted through the lens to the image. It is frequently the...

A technique for improving the structure density of thin-film coatings by bombarding the growing film with accelerated ions...

After putting a thick photographic emulsion on a front-faced mirror, and exposing the emulsion to monochromatic incident...

A lab-on-a-chip (LOC) is a miniaturized device that integrates various laboratory functions and capabilities onto a single,...

An optically bistable device used for photonic switching, constructed of a multiple quantum well biased by an external...

1. An instrument used to determine the visual range in an environment. 2. A type of photometer that artificially reduces an...

The apparent color, as seen by the human eye, as distinguished from color as a measurable property of light.

A device used to accelerate the electrons in a free-electron laser. There are several types, including the induction linear...

Germicidal ultraviolet (GUV) refers to a specific range of UV radiation that has disinfectant properties capable of killing...

A measure of the transmittance through an optical medium. Optical density equals the log to the base 10 of the reciprocal of...

An interference pattern that is recorded on a high-resolution plate, the two interfering beams formed by a coherent beam...

A plate of glass, usually a photograph, on which there is a central spot surrounded by concentric annular zones, alternately...

The forming of a clear silhouette of an object by placing a light source behind it. Used in machine vision when surface...

A defect of vision where a single object appears as two. Also known as double vision.

Technique that provides two stereographic views of an object that are larger than the object itself, by means of mutually...

Photodynamic inactivation (PDI) is a therapeutic approach that utilizes the combination of light, a photosensitizer, and...

The departure of an optical surface from its required tolerance or figure.

Fluence is a term used in various scientific and technical disciplines to describe the amount of something per unit area....

In a laser, the series resistance necessary for a stable electrical discharge.

The simplest method of transmission on a local area network. The entire bandwidth of the cable is used to transmit a single...

An optical waveguide in which only the lowest order bound mode, which may consist of a pair of orthogonally polarized...

In optical character recognition, a feature at the boundary of a character.

Optical confinement of matter with high field energies intended to induce a stable nuclear fusion interaction.

A YAG crystal refers to a solid-state crystal made of yttrium aluminum garnet (YAG), which is a synthetic crystalline...

A solar spectrograph that uses long focus concave mirrors as its collimator and camera element.

The science of all complex elements of atomic and molecular spectra, and the interaction of radiation and matter.

Lenses that have identical flange focal distances and can be interchanged.

A coupling mechanism designed to quickly lock a connector into an adaptor or a lens into a lens mount. Typically coupling is...

A photographic enlarger with a fixed negative plane and a fixed paper plane, often using a roll of paper that is advanced...

A spectrometer equipped with polarizing prisms and retardation plates that is used in the analysis of elliptically polarized...

Graphic evaluation of the operation of a steam thermodynamic cycle of a solar energy system on which enthalpy is plotted...

An optical component coated to reflect infrared radiation. Gold, silver and aluminum are typical coating materials.

Mod Method of obtaining precise temporal mode characteristics.

An intensity distribution (intensity as a function of radial distance from the beam center) which is given by the Gaussian...

An optical instrument for forming the spectrum of a light source and recording it on a film. The dispersing medium may be a...

An array of active optical devices (modulators, laser diodes and/or detectors), each of whose electrical inputs or outputs...

The capacitance of a capacitor which has a potential difference of one volt between its plates when it is charged by one...

A small mass spectrometer used to find leaks in a vacuum system by detecting the presence of helium. Using a magnetic...

A vacuum tube with an electron gun at one end and a fluorescent screen at the other. Electrons emitted from a heated...

Machine learning (ML) is a subset of artificial intelligence (AI) that focuses on the development of algorithms and...

Focal, nodal or principal points of a lens. If the respective distances of the object and image are measured from the...

An objective that uses the mineral fluorite in its construction to reduce the secondary spectrum. It is usually intermediate...

Spectroscopy characterized by the Mossbauer effect - recoilless emission and absorption of nuclear gamma radiation- which...

A method for detecting vibration amplitudes analogous to image holography, except that the film emulsion is replaced by a...

The storage of information via optical means, primarily employing a low-power laser to inscribe data on a photosensitive...

In a laser, the voltage necessary to sustain a constant operating current, somewhat less than that needed for start-up.

A statistical method of dealing with a series of values where each value is squared, the mean of these squares is...

Fresnel reflection refers to the reflection of light at the interface between two different media with different refractive...

The measurement of the rotation of the plane of polarization of radiant energy, usually through the use of a polarimeter.

A photoreceptor material used in solar cells and in drums for laser printers and high-speed copiers because of its high...

A type of solar eclipse that occurs when the sun is at perihelion and the moon is at apogee. Because the apparent size of...

A device, consisting of a diode activated by an interference pulse, that is designed to minimize the white spots on a...

An optical system in which the only image-forming elements are curved-surface mirrors; e.g., a Cassegrain lens system.

An instrument used to record rapidly varying currents or voltages. An oscillograph may consist of a cathode-ray tube...

Activity of a radionuclide having one spontaneous nuclear transition per second.

A glow discharge lamp consisting of a cold cathode and a mixture of inert gases. The intensity of illumination varies with...

A sealed, hard, magnetic disc drive used for the storage of data in a computer system.

Irregular waves; e.g., light waves, having little coherence and a broad spectrum of frequencies.

The departure of a curved surface from the plane that is tangent to its vertex. See sag.

An electron-beam lithography (EBL) system is a sophisticated nanofabrication tool used in the semiconductor industry and...

A paraboloidal surface on which the image is located when there is no astigmatism.

A reference sphere used to represent all possible states of polarization. All linear polarizations will lie on the equator...

The formation of a dark-colored film on a metal surface by chemical activity.

A retroreflector is an optical device or structure that reflects incident light or electromagnetic waves back to their...

A vacuum chamber is a sealed enclosure from which air and other gases are removed to create a low-pressure environment,...

A transmission interference microscope that produces interference patterns of a sample by using birefringent plates that...

The number of separate images exposed by a cine camera in a second or the number illuminated by a cine projector in a...

A reference incandescent light source having a luminous intensity that is used in photometry for comparison of other light...

A contraction for "texture element." A base unit used in computer graphics that defines the surface of three-dimensional...

Polymers are large molecules composed of repeating structural units called monomers. These monomers are chemically bonded...

A lateral shearing interferometer is an optical device used in interferometry to measure phase differences between two beams...

A vacuum pump in which heated oil or another substance is forced through jets as a vapor that collides with gas molecules...

The naturally occurring crystalline form of silicon dioxide. It is slightly birefringent and exhibits rotary dispersion of...

The distortion that is the result of viewing a print from a point other than the center of perspective. The center of...

That branch of astronomy concerned with the study of the moon's physical characteristics.

A device that functions throughout the continuous radiation of a linearly polarized plane wave, and whose nonreciprocity...

A mass spectrometer used to detect ions formed by photo- and charge-exchange ionization of gases, such as those in the lunar...

The indistinct, less luminous portion lying immediately outside an electric arc whose spectrum often differs from that of...

A spectrometric instrument that detects radiation simultaneously in multiple channels, sorts it spectrally from the deep...

The concept of the de Broglie wavelength exploits the wave-particle duality of quantum physics by associating all matter (of...

The higher throughput obtained with an FTIR device compared with traditional spectrometers that need slits to achieve...

Reciprocal magnetic interaction between nuclei in a molecular system facilitated by the binding electrons of the molecule.

A computer hardware unit that generates required functional information on the screen by controlling CRT beam movements or...

Also known as UV-VIS spectrometer, a device that measures the absorbance, reflectance or transmittance of light in the...

The application of reversible writing with a laser beam on particular storage materials. In one method, an amorphous film is...

In a lens or lens system, that surface at which the projections of an entering and exiting ray intersect. Also known as the...

A type of laser used when a great amount of power is required. Avoiding the bulk of large numbers of optical lenses, this...

The transition cross section constant coefficient which defines the transition probability of absorption from ground to a...

A solution containing colloidal silica particles.

A method used to compare two pictures of the same subject taken at different times. See image comparison.

A device used to measure directional reflectance, with light collection restricted to a narrow range of angles of which the...

A technique for reducing data processing requirements by electronically defining only a small portion of the image to be...

That radiation characterized by wavelengths ranging from 0.2 to 0.3 µm in the electromagnetic spectrum.

An instrument, similar in design to regular binoculars, that can transmit and enlarge infrared images.

An operational mode for radiometers that analogs the method of operation of an angstrom pyrheliometer. In this mode, the...

Optics is the branch of physics that studies the behavior and properties of light, including its interactions with matter...

A narrow linewidth optically transmissive or reflective component intended for use with a highly monochromatic or single...

The development of a transverse electric field in a solid material when it carries an electric current and is placed in a...

The point to which the extension of the straight line, reaching from the sun to the observer's eye after penetrating the...

A camera designed with a telecentric optical system and a narrow field of view; the telecentric optical system (placement of...

The process by which laser emission is used in measuring fluid velocity and, more specifically, the detection of air and...

A CCD sensor that provides feedback to the motion control system for a telescope, allowing the telescope to follow a...

Colors that produce an achromatic color when additively mixed.

In chemistry, a halide refers to a chemical compound containing one or more halogen atoms bonded to another element. The...

A device used to measure the masses and relative concentrations of atoms and molecules. It utilizes the Lorentz force...

A bundle of optical fibers arranged randomly for the purpose of transmitting energy, not an image.

Intense scattering in the region of the liquid-gas critical point. At this point the gas will strongly scatter all light to...

A semiconductor formed by applying a particular single-crystal layer to the specific insulator.

A magnetometer is a scientific instrument used to measure the strength and/or direction of a magnetic field. It can detect...

Optical fiber channel characterization scheme based on three assumptions; the discrete mode spectrum can be replaced by a...

Chip-on-board (COB) lights refer to a type of LED lighting technology where multiple LED chips are directly mounted onto a...

The occurrence of very large rotations in transparent materials at weak magnetic fields as predicted in the classical...

The fundamental tool of microdensitometry, the microdensitometer is an instrument used for the precise measurement of...

A composite derived from aluminum alloy powder and silicon carbide, used as an optical substrate in air- and spacecraft...

The ray refracted by a sphere of transparent material that travels back as closely as possible to the original path formed...

A two-part lens that has a different focal length for each part. Generally, it is used in eyeglasses to correct for both...

The difference in electrokinetic potential between the stationary liquid connected to a solid phase surface and the mobile...

Imaging radar that increases the sweep of its along-track (or azimuth) capacity by measuring not only the time delay of the...

Contains the light or beam path within a laser device. The oscillator uses reflective optical components that are oriented...

Term applied to radiation composed of particles or photons that will not easily penetrate a material because of their low...

The distortion in an ophthalmic lens resulting from the refraction of light rays entering the periphery of the lens surface....

A unit of luminance equal to 1/p candela per square centimeter. (l).

An eyepiece similar to the Huygenian eyepiece, but having an eye lens that is a cemented doublet and that provides more...

Not spherical; an optical element having one or more surfaces that are not spherical. The spherical surface of a lens may be...

Also called color blocking. The formation of a block by making optical contact between a number of optical elements and a...

The branch of optics that deals with the study of the refraction of light, particularly by the transmitting medium of the...

The effect by which sufficiently small particles will scatter blue light at right angles to the incident beam. This...

The pattern of lines traced by rectilinear scanning in display systems.

The visual phenomenon of the apparent difference in the rate of motion of two objects that are actually moving at the same...

The laser output refers to the generated and emitted light produced by a laser system. This output is characterized by...

A microscope equipped with a polarizer, an analyzer and a Bertrand lens to focus on the upper focal plane of the objective....

A position inside a crystal lattice that is not one of the proper lattice sites in the crystal. Impurity ions of the proper...

The use of photoelectric sensors to detect and measure the intensity of a light source. This application, as compared to...

The distortion of an image formed by a cathode-ray tube, caused by unbalanced deflection voltages or deflection voltages...

Electronic circuit capable of distinguishing the pulses emitted by separate counters in a given time phase and determining...

An infrared source, set in a stationary position, that is used as a reference in certain navigational systems.

Mode hopping in the context of lasers refers to a phenomenon where a laser system abruptly switches from one longitudinal...

The transfer of a part of a device's or circuit's output back to its input.

The visual examination by a trained observer of the image of a point source. Any coloring or departure from the Airy disc...

The photographic recording of visible and ultraviolet spectra on an ordinary photograph.

A lens having each of its outer faces curved outward.

Computation of tristimulus values by integrating or summing, over the visible wavelength region, the product of the relative...

A low-power telescope with a wide field of view, typically attached to a higher power telescope with a narrower field of...

Spectrometric analysis of the distinct and characteristic spectra of atoms of elements. The atoms are energized to emit...

A perfectly diffusing surface; the intensity of the light emanating in a given direction from any small surface component is...

A thermal-infrared camera, often referred to simply as a thermal camera, is a type of imaging device that detects infrared...

An electro-optic system using, in general form, an evacuated glass envelope with a semitransparent photocathode at one end...

A fiber optic transceiver, often simply referred to as an "optical transceiver," is a device used in fiber optic...

In data transmission, a self-checking code using a separate bit (the parity bit) to assure that all bytes of transmitted...

Multi-axis alignment refers to the process of aligning or adjusting components or systems in multiple spatial dimensions or...

A system that generally uses a photodetector to decode punched cards for information, or for input to a computer, by sensing...

A type of quarter-wave retarder in the form of a glass rhomb; light entering the retarder undergoes two total internal...

Characteristic of deflected light power defined as the quadratic invariant function of the video signal amplitude.

The pattern, formed by a character generation cathode-ray tube system, in which the characters are made up of wave shapes...

A surveying map representing measurement of depth, particularly that of the ocean.

The term "embedded laser" typically refers to a laser device that is integrated or embedded into a larger system or...

On a display monitor, a small, mobile rectangle, cross-hair or pointer that locates a feature in an image that is the object...

The ability of a conductor to store an electrical charge; its value is given in farads as the ratio of the stored charge on...

The product of Avogadro's constant and the electrical charge of an electron; thus, the electrical charge carried by 1 gmol...

A polished plano-parallel plate that is contacted to an unpolished glass surface to permit see-through analysis of the...

Photolithography is a key process in the manufacturing of semiconductor devices, integrated circuits, and...

Spectral flow cytometry is an advanced flow cytometry technique that expands the capabilities of traditional flow cytometry...

A type of motion-picture camera in which single frames are photographed either automatically at a predetermined rate (as...

The acoustical holographic process in which the hologram consists of slight elevations in a liquid surface, in the areas of...

A laser capable of generating light pulses that last only a few femtoseconds. This can be achieved by nonlinear filtering to...

The photomicrographic recording of Schlieren effects, irregular refractions of light from optic surfaces or areas of thin,...

An early type of nonvacuum photocell consisting of a layer of copper oxide on a metallic substrate, with a thin transparent...

The transfer of energy from an incident electromagnetic energy field with wavelength or frequency to an atomic or molecular...

Optical elements that use diffraction to control wavefronts. Diffractive optical elements include diffraction gratings,...

A shutter having one or more roller blinds of material with a variable slit that moves across the back of the camera when...

A condition in which the solid inclusions within a glass blank are very numerous, such as 25 or more to the square inch.

A silicon photodiode is a semiconductor device that converts light into an electrical current. It is a type of photodetector...

Ophthalmology is a branch of medicine that focuses on the anatomy, physiology, and diseases of the eyes and visual system....

In image processing, machine vision and television, discrete brightness values quantized for a group of pixels. They can...

A lens that is implanted within the eye to replace the eye lens, which has been removed because of cataract or other defect.

An electromagnetic device used to separate isotopes of elements based on their respective masses.

The chemical method of separating compounds dissolved in one phase (usually mobile) through its equilibration with a second...

A laser in which stimulated emission is triggered by the absorption by electrons of light from an auxiliary source such as a...

The combination of two waves having the same frequency and amplitude and traveling in opposite directions. Standing waves...

1. In the geometric sense, an abbreviation for the term "sagitta,'' the height of a curve measured from the chord. ...

A lens assembly containing several movable elements to permit changing of the effective focal length (EFL). Unlike a zoom...

A near-infrared (NIR) camera is an imaging device designed to capture images in the near-infrared region of the...

In micropositioning, a remote positioning device in which an electric current drives a movable armature mounted on an...

Generally, a rotatable table with scales marked in degrees. The fiducial marking also may be a vernier scale. The same...

With respect to photography, the change in the density-exposure relations, for small details of the photographic image, that...

An optical system that records inhomogeneities within a medium by detecting the energy refracted by that portion of the...

Nonlinear optical materials are substances that exhibit optical properties that are not linearly proportional to the...

An instrument incorporating an infrared detector assembly, used to analyze carbon dioxide gases and in medical applications...

A direct-vision prism made in one piece that can be used only in parallel light.

A photometer that permits visual comparison of the luminance of two surfaces.

1. The focal point. 2. To adjust the eyepiece or objective of a telescope so that the image is clearly seen by the observer....

A vibrational transition refers to a change in the vibrational energy of a molecule. Molecules consist of atoms that are...

The Casimir force is a quantum phenomenon that results in an attractive force between two closely spaced uncharged...

Phase shift in electromagnetic signals caused by daily variations in the ionosphere, often during sunrise or sunset.

Self-phase modulation (SPM) is a nonlinear optical phenomenon that occurs when an intense laser beam passes through a...

A chart, either printed on paper or prepared photographically on glass plates or film, that consists of 3-bar resolution...

Single molecule localization microscopy (SMLM) is a group of super-resolution microscopy techniques that surpass the...

Irradiance per unit wavelength interval at a given wavelength, expressed in watts per unit area per unit wavelength interval.

Nonspecular reflection from a rough surface.

A frequency comb is a precise and regular series of equally spaced spectral lines, or frequencies, that are generated with...

Material used to integrate photoconductors into electro-optical systems. It should provide low resistance to the flow of...

Able to rotate the plane of polarization of a transmitted, plane-polarized light beam clockwise as seen by a viewer looking...

1.) Generally, the electromagnetic spectrum within the wavelength region extending from the vacuum ultraviolet at 40 nm to...

Device which determines particle velocity through the measurement of scattered interference of a beam pair from a single...

A computer architecture used in parallel processing whereby the processing elements are directed by a single, central...

Optical components, usually reflectors, produced using proprietary techniques that transfer the precision of a master to a...

An aptamer is a short, single-stranded DNA or RNA molecule that can bind to a specific target molecule with high affinity...

An optical clock is a highly precise and advanced timekeeping device that relies on the oscillations of electromagnetic...

Measures the absorption or sample transmittance over a range of specified wavelengths. Sample may be placed within the...

Glass that transmits near-ultraviolet radiation but is opaque in the visible region. Also known as woods glass.

Advanced driver assistance systems (ADAS) refers to a set of safety features and technologies designed to assist drivers in...

Edge enhancement with a directional characteristic.

In physics, the law of reversibility is often associated with the concept of reversibility in thermodynamics. The law...

A diagnostic instrument that uses a photocathode design to see a broad range of x-ray radiation by streaking the...

A set of samples used in the analysis of multielement thin films.

A photoconductor that demonstrates increased conductivity during its exposure to infrared radiation.

Aplanatic points refer to specific points in an optical system where certain aberrations, such as spherical aberration or...

The change in refractive index that occurs as acoustic vibrations are transmitted through an optical material.The index...

The movement of particles or ions in a solution toward the electrode having the opposite sign because of the application of...

Mode-locking is a technique used in lasers to produce ultrashort pulses of light with durations on the order of picoseconds,...

iris or adjustable radially symmetric opening used for allowing the passage of useful light

An interferometric technique for the generation of precision gratings that allows for sequential exposure of small segments...

In optics, an octave typically refers to a range of frequencies or wavelengths that spans a factor of 2. In other words,...

Calculation of the amount of energy extracted from a light beam regardless of its wide range resolution.

Liquid crystals are a state of matter that exhibits properties intermediate between those of conventional liquids and solid...

A refracting telescope that uses a prism to bend the line of sight 90°.

A beamsplitter is an optical device for dividing a beam into two or more separate beams. A simple beamsplitter may be a very...

1. In raster scan television, one of the two scans that are interlaced to make up a frame. 2. See field of view.

The lens of an eyepiece nearest the observer's eye.

A crystal that is characterized by its relatively poor electrical conductance.

The apparent visual angle that divides intrabeam viewing from extended-source viewing.

A CCD device for sensing longer wavelengths, such as NIR and IR, that has a deeper depletion region than would be necessary...

The minimum energy required to induce atomic and molecular separation or displacement due to incident intense laser...

The instrument used to collect thermal radiation information on an object by scanning. It consists basically of a detector,...

The rule stating that positive uniaxial crystals have greater absorption with respect to the extraordinary component of...

A transistor that uses an electro-luminescent source, a transparent base and a photoelectric collector.

The sunlight that extends to the earth after scattering from other solar bodies, mostly from meteorite dust of radii...

The inhibition or elimination of one process by another process. The stimulated emission of a laser oscillator can be...

An excimer laser is a type of ultraviolet laser that emits short pulses of light in the ultraviolet spectrum. The term...

Calculation of gas and aerosol transmission and emission characteristics for several model atmospheres, including two model...

The distance between the base and the vertex before the edging of a prism.

An arc lamp that has its cavity filled with krypton to produce a light source with unique characteristics.

A light-tight box that receives light from an object or scene and focuses it to form an image on a light-sensitive material...

An optical resonator in which feedback is accomplished by two parallel planes. In diode lasers, the planes are obtained by...

One area of image enhancement, accomplished by spatial filtering schemes, that usually involves attenuation of phase changes...

A testing device that provides a contour map of the emergent wavefront for the observer in terms of the given wavelength of...

The center of a local area network in the star topology.

The slight difference in wavelength of an element's given spectral line observed in comparing different isotopes of that...

The formation of a fan of light or energy rays in a beam as the beam passes through an extremely narrow aperture.

A system composed of a prism spectroscope and compound microscope to provide the visual comparison of two spectra...

A laser cavity, also known as an optical cavity or resonator, is a fundamental component of a laser system. It is a confined...

A small card (10 x 15 cm) that has been treated with a photographic emulsion to record and store the microimages of...

The amount of x-rays used to penetrate and diffuse a target sample undergoing electron-probe microanalysis.

Localized variations in the purity and the index of refraction of the atmosphere.

An aerial reconnaissance system that can transmit, in near real time, image data recorded by IR and visual-spectrum sensors,...

With relation to the equivalent beam candlepower of a searchlight, the candlepower of a bare source that would produce the...

A single-photon avalanche diode (SPAD) is a specialized type of photodetector designed to detect extremely weak optical...

A thermal radiation detector consisting of a small cell with a blackened plastic front face that bulges slightly when heat...

The process of mapping the infrared emittance of an area through the use of an infrared detector and related scanning...

Optical design software refers to specialized computer programs used by optical engineers, physicists, and designers to...

The optical element that receives light from the object and forms the first or primary image in telescopes and microscopes....

Custom lapping and polishing services involve specialized processes used to improve the surface finish and dimensional...

Double-clad fiber (DCF) is a specialized optical fiber that features two concentric cladding layers surrounding a core. The...

The production of rough glass lens blanks that are pressed while red-hot to the approximate size and shape of the finished...

The part of an electrical circuit in which the electrons leave (a cathode-ray tube) or enter (an electrolytic cell) a unit...

In a lens system, a group of elements considered as an entity; either a front or rear member depending on whether it is...

A fiber optic imaging bundle is a specialized optical device composed of multiple optical fibers bundled together. Each...

A measuring instrument used for surface profiling and quantifying the roughness of a material. The stylus is placed on the...

A bright spot or point, due to Fresnel diffraction, that appears at the center of the shadow of a circular object in light...

Interruption in the normal flow of a plasma or fluid characterized by sharp rises in velocity, temperature and pressure. As...

An infrared detector that achieves a specified sensitivity through the application of certain cryogenic temperatures.

Calculations of lens aberrations whereby the first two terms of the series expansion are the only ones employed....

A device used in ultrasonic imaging to measure the velocity and attenuation of compressional waves in a transparent liquid...

Supercontinuum refers to a broad spectrum of light that spans a wide range of wavelengths, typically from the visible to the...

A semiconductor laser that operates in the infrared and that is pumped with strong pulses of radiation from a second laser....

An optical instrument designed to displace the line of sight in a vertical direction. For submarines and other military uses...

A nonlinear optical process in which the frequency of an optical beam is doubled coherently.

Base area of a laser unit.

A wide-angle lens is a type of camera lens that has a shorter focal length than a standard or normal lens, allowing it to...

A device to modulate spatially a collimated coherent beam of light with input data in optical data processing. It uses a...

A visual display used with a computer to give access to the many elements of data as an array of points. With the display...

Camera designed for the imaging of the earth's surface in order to obtain high quality aerial images

A waveguide with a rectangular cross section that is composed entirely of dielectric materials.

A specific type of filter designed to reduce the amount of light scattered by reflections from the edges of optical...

A polarizer that consists of dichroic polarizing material embedded in a plastic sheet, and that transmits light that is...

A viewer that uses the transmittance of polarized light through glass or a similar medium to examine strained regions. See...

An image of an object that appears above the object's true position as the result of abnormal refraction of the image rays...

The halo phenomenon of a brightly colored arc having the colors of the rainbow and lying parallel to the horizon.

Output noise in a laser beam resulting from acoustic disturbances of mirror separation or orientation. Such disturbances may...

A set of international standards by which a single telecommunications channel is used to transmit voice and data...

A photosensitive device used to optically scan and read character data (numbers, letters etc.) and input this data into a...

A gas maser that is capable of producing radiation in the far-infrared region of the spectrum.

The coefficient termed by Callier as the ratio between the density of photographic negatives measured by parallel light and...

Also known as real holographic image. The indistinct, highly distorted image produced on the side of the hologram closest to...

A collimator having, at one end of a tube, an objective lens, and at the other, a reticle with a pair of spaced lines...

An expression of the tolerance of decentration of a laser diode from the optical axis: the region around the axis in the...

A measure of an optical system's ability to produce an image which separates two points or parallel lines on the object. See...

A fiber optic preform is a cylindrical glass rod or tube used as the starting material for manufacturing optical fibers. It...

A two-fiber optical cable containing two single-fiber cables that are connected by a strip of jacket and that can easily be...

A scanning technique in which the optical density of the film being scanned controls the speed of deflection of the scanning...

A type of computer in which the electronic circuits, which process data serially, are replaced by photonic circuits capable...

A pollution-measuring device used to detect the presence of nitric oxide regardless of other gases present. It utilizes the...

Inertial fusion energy (IFE) refers to a proposed method of generating electricity by harnessing the energy released from...

A spheric lens, also known as a spherical lens, is a type of optical lens with at least one surface that is part of a...

A CMOS camera refers to an imaging device that employs a complementary metal-oxide-semiconductor (CMOS) image sensor to...

A class of optical phenomena that can be viewed only with nearly monochromatic, directional beams of light, such as those...

Formulaic compensation to correct laser ranging data for the effects of horizontal refractivity gradients; it requires the...

The process of sealing laser components by means of frit seals, welding or bonding rather than using epoxy.

A distributed feedback laser (DFB laser) is a type of semiconductor laser diode designed to emit coherent, narrow-bandwidth...

The methods and techniques used to obtain medical photographs of the human eye. To photograph the exterior of the eye,...

In image processing, methods of reducing image defects that result from false data. Techniques include sampling, linear...

The refraction that would take place in an idealized atmosphere where the refractive index is reduced uniformly with height...

Any of the five elements astatine, chlorine, fluorine, bromine and iodine, grouped because their chemical properties are...

A rear or front projection screen composed of minute optical surfaces that introduce a spread to the light beam that...

A system employing a dark trace tube in which the opacity of the screen is varied as a function of the power of the beam.

A large telescope mirror fabricated from several smaller sections.

1. The use of an electronic microdensitometer to measure points of equal density on a photographic deposit. 2. A technique...

The active control of various aspects (optical element position, airspace thickness, etc.) of an optical system that...

A spectrograph having glass as its refracting component and used in cases where speed and high dispersion are not required....

The light emitted from tissues without the use of fluorescent dyes as markers. Because cancerous tissues and normal tissues...

Combining adjacent pixels into one larger pixel, resulting in increased sensitivity and lower resolution, or, in image...

The angular spectrum approach is a mathematical and computational technique used in the field of optics to analyze and...

A type of mirage that creates a distorted vertical image of relatively flat objects so that they appear as mountains,...

The perpendicular orientation of the molecular axes of the nematic molecules in a nematic crystal, relative to the electrode...

An electronic device used to encode video and audio signals of a television camera into radio waves that are broadcast to...

Also known as reversed telephoto lens. A lens consisting of an ordinary objective with a negative component near its front...

Substances that exhibit the characteristics of both acids and bases and are capable of both P- and N-type conductivity.

Color vision whereby abnormal proportions of three colors are needed for color matching.

An automatic surface-generating process involving the removal of a material from a given surface. Optical milling typically...

A laser effect used especially for laser light shows. Lumia are created by placing a distorting medium such as rippled glass...

The angular field of view that is seen by the eyes when fixed on a point straight ahead. The normal binocular visual field...

A combination spectrometer and bolometer that is designed to measure a narrow band of radiation from a star.

A thick meniscus lens arranged concentric with the center of curvature of a spherical mirror to produce an image free of...

A wide-field camera based on the classic Schmidt optical system used to photograph Earth-orbiting satellites.

The optical phenomenon in which right circularly polarized light transmitted by an active medium travels at a different...

Fluorescence produced by a material that has been treated with a dilute solution of fluorescing material.

Embedded vision refers to the integration of computer vision technologies into various embedded systems, devices, or...

Transparencies that represent progressive steps in the amount of transmitted radiation for administering predetermined...

The allowable departure from the given figure or geometrical form. It may be described in terms of fringes or wavelengths.

Glass tinted with mixed oxides of neodymium and praseodymium that, unlike most solid materials, have absorption bands that...

A spectral signature, in the context of remote sensing and spectroscopy, refers to the unique pattern or characteristic...

A photon-counting instrument for use in both space-borne and ground-based photometric and spectroscopic instrumentation....

In optics and photonics, "phase" refers to a property of electromagnetic waves, such as light, that describes the position...

The formation and display of three-dimensional images by ultrasonic energy. In one technique, the energy pulses from an...

Lenslike composition of stacked glass cylinders through which a spot of light appears as a streak perpendicular to the...

Heat measurement method in which the sample is made part of the interferometer and the temperature increase is determined by...

The study of the arrangement of atoms in a crystal by means of x-rays.

The adjustment of a binocular instrument so that the lines of sight of both telescopes are parallel.

An optical fiber in which ions of a rare-earth element, such as neodymium, erbium or holmium, have been incorporated into...

Solar regions characterized by low density and open magnetic fields where high-speed solar wind streams originate....

An optical instrument consisting of a well- corrected objective lens or mirror with a light source and or object/image (i.e....

The point at which infrared transmission is cut off.

The projection of the image beam by a cathode-ray tube through a mask, where it is deflected through the suitable character...

GaN (gallium nitride) distributed feedback (DFB) lasers refer to a specific type of semiconductor laser based on Gallium...

Metrology is the science and practice of measurement. It encompasses the theoretical and practical aspects of measurement,...

Anisotropic is a term used to describe a material or substance that exhibits different properties or behaviors in different...

An instrument used to record infrared images of large areas. The recorded data are used to produce maps in false color...

The movement of particulate material by flowing gas or liquid.

An electric discharge between two carbon rods that are touched together to start the arc and then separated slightly. The...

Hyperspectral resolution refers to the level of detail or granularity in the spectral information captured by a...

The term "Rydberg atom" refers to an atom in a highly excited state where one or more of its electrons are in a Rydberg...

A device used in a free-electron laser to convert the electron-beam's energy into microwave laser radiation by creating a...

The phenomenon that makes nonlinear the mathematical expression for the electrical polarization of a medium through which...

Complementary metal-oxide-semiconductor (CMOS) refers to a technology used in the fabrication of integrated circuits,...

Phototherapy is a medical treatment that involves the use of light to treat various conditions, particularly those related...

Spectrum broadening that results from the influence of an electric field.

A form of photometric measurement, often used with light sources that are transparent or fluctuating, in which a...

A PN-PN device with incident light taking the place of gate current; three of the four semiconductor regions are available...

Film in which electric polarization is reversible when influenced by an electric field.

A two-electrode, radiation-sensitive junction formed in a semiconductor material in which the reverse current varies with...

A discharge tube filled with various gases and used as a source in spectroscopy.

An advanced technique that allows the detection of one molecule within a crystal or a cell through optical excitation....

The surface curvature designed to reduce the marginal error found in the periphery of a spectacle lens.

A high-quality, narrow-angle lens of high aperture designed for low magnification in the recording of cathode-ray tube...

A material that is present or added to a sample undergoing spectroscopic analysis, to serve as an intensity reference for...

Means of amplifying optical waves whereby an intense coherent pump wave is made to interact with a nonlinear optical crystal...

A device, also called a fluorescence lifetime instrument, that measures decay curves of fluorescing samples. It generally...

The coupled pairs of electrons that carry supercurrents through the body of a superconductor, relative to a coherent...

An analog method of moving a cathode-ray tube beam across a display screen face, commonly used in high-performance vector...

A machine vision system is an integrated combination of hardware and software components designed to capture, process, and...

A device for obtaining very low crosstalk in a crosspoint by arranging two simple switches along different arms of a passive...

Irradiation of a cylindrical crystal with an x-ray beam resulting in Bragg diffraction that produces a slightly enlarged...

An adhesive whose viscosity decreases as the temperature is increased to a limit. Canada balsam, resin and pitch are...

A photograph reduced to the microscopic scale and stored on a microfilm as seen with microfiches for the purpose of storing...

A cosmetic defect on the surface of an optical element. A dig is nearly equal in terms of its length and width. The size is...

The constant outward flow of weakly magnetized plasma from the sun that is deflected by the magnetic field of the earth and,...

The plot that expresses a reaction rate vs. the reciprocal of absolute temperature. Often used to describe the thermal...

Birefringence is an optical property of certain materials that causes them to exhibit different refractive indices for light...

The photographic recording of a subject that exhibits luminescence only for an extremely short time (10-8 s) after the...

Fraction of light counter propagating collinear with the incident source. Processes considering backscattering are Raman,...

Primary image memory that is built into a digital camera and stores the digital images generated by the camera's image...

The noise produced in a photodetector when the photocathode is shielded from all external optical radiation and operating...

The reddish/purple color that results when equal amounts of blue and red are combined so that no one wavelength dominates.

A light source, such as the sun or an incandescent lamp, that freely penetrates ordinary glass bulbs and emits in the...

The physical adaption of the eye lens, by means of ciliary muscle contraction, in order to maintain a clear, in focus image...

The first nonlinear theory in plasma physics that details the time and space evolution of plasma wave instability from a...

The decay of an electrostatic charge image resulting from long exposure to the dark.

1. Viewed with one eye. 2. Describing an image as viewed from a single angle.

In the region of a Gaussian beam focus by a diffraction-limited lens, it is the axial distance from the point of minimum...

A doped or absorbing transparent medium cut or molded into a wedge in order to measure the real and imaginary components of...

The simulation of solar radiation in the infrared and ultraviolet spectrum for the analysis of extraterrestrial sunlight and...

A toric lens generated by rotating a specific cross section about an axis beyond its area and used in the formation of...

An Er:YAG laser is a type of solid-state laser that uses a crystal made of erbium-doped yttrium aluminum garnet...

A process of forming ions within a given molecular species by incident laser light. The molecular species may remain intact,...

The methods used to determine the extinction characteristics of a medium.

The photographic recording of data, in binary form, for storage in memory. Exposure is achieved by a cathode-ray tube or by...

A naturally occurring pigment in tissue that may selectively absorb certain wavelengths and can be used to aid in targeting...

A planar photocathode and a planar phosphor screen mounted in a close-spaced parallel configuration in an evacuated...

A type of distortion in which the magnification varies in different orientations, the directions of maximum and minimum...

The use of a reflective device, which can be fashioned from a variety of materials including gases, solids, dyes, aerosols,...

The fringes used in the Jamin interferometer and produced by light that has been internally and externally reflected by two...

A camera mounted on an optical bench with an easel to hold the material to be copied. Magnification can be varied over a...

Multispectral imaging is a technique that involves capturing and analyzing images at multiple discrete spectral bands within...

The series of rings or bands formed when light beams reflected from two polished, adjacent surfaces, placed together with a...

A large tank filled with liquid hydrogen, with a flat window at one end and complex optical devices for observing and...

A device attached to the end of an alignment telescope that detects and calculates a plane mirror's rotation axis that is...

The vertical angular disparity between the lines of sight of the left and right systems in a binocular instrument....

Cyan, magenta and yellow. They are called subtractive because they each subtract one color by absorbtion and reflect the two...

In Stimulated Brillouin Scattering (SBS), an incident photon (usually laser light) interacts with acoustic phonons in a...

The luminescence displayed when particular minerals are irradiated with β-rays and g-rays, after being exposed to...

A laser in which the transition involved in stimulated emission of radiation takes place between two levels of an ionized...

FTIR (Fourier transform infrared) spectrometer is a powerful analytical instrument used to obtain an infrared spectrum of...

Transmittance of a solution, or internal transmittance of a transparent solid, is an exponential function of the thickness...

The narrowest line of the cadmium spectrum; the red line has the purest radiation.

The current that flows in a photodetector when there is no optical radiation incident on the detector and operating voltages...

An apochromat, often referred to as an apochromatic lens or apochromatic objective, is a type of optical system designed to...

In optical fiber, bends that are larger than microbends (see microbending), being visible. Generally they are caused by...

A pair of stars (double star) that can be seen separately with a telescope, generally by setting a filar micrometer for the...

The darkening of the laser facet of a semiconductor laser diode. It can be prevented by placing the component in a...

Laser texturing is a manufacturing process that involves using a laser beam to selectively modify the surface of a material,...

A technique of optical storage whereby information is encoded by molecular alterations in the interaction between the...

One class of nonlinear space-invariant transformation processes used for processing convolved and multiplied signals.

GigE, short for gigabit Ethernet, refers to a standard for high-speed Ethernet communication, capable of transmitting data...

A solid-state laser using yttrium aluminum garnet as the matrix material, doped with neodymium (Nd:YAG).

An achromat, in the context of optics, refers to a type of lens or lens system designed to reduce chromatic aberration....

The shortest wavelengths of the infrared region, nominally 0.75 to 3 µm.

The mounting of a concave diffraction grating and a plate holder at the ends of a rigid bar. The ends follow separate...

An instrument that produces an intense, tightly focused beam of ions to stimulate emissions from a minute section of a...

The light-sensitive cells on the retina of the eye that are responsible for low-resolution, peripheral vision.

An electron tube containing neon gas that uses the transmission of an electric current through the gas to ionize the neon...

Laser surgery refers to a medical procedure in which a laser, or focused beam of light, is used as a precision tool to cut,...

A characteristic of optical fiber used to calculate the fiber's ability to maintain polarization. The beat length describes...

A scanning technique in optical character recognition in which an array of photocells is used to scan each character to...

An imaging device originally created to image whole mouse brain volumes at microscopic resolution. The main component of the...

The bands found by Vegard in the spectrum of the aurora borealis and by Kaplan in the nitrogen afterglow. They are formed by...

A term variously applied to remote sensing techniques that essentially refers to all parametric conditions that influence...

A line formed by the principal (center) ray of an oblique bundle of rays.

A photometer screen that contains a diaphragm of paper or parchment with a translucent central spot of oil or paraffin.

Measure of a detector's signal during exposure to radiation of a constant power level and varying wavelength.

A thermogram in which temperature values are displayed in discrete thermal bands, each band possessing a distinct color.

Broadband dielectric mirrors, also known as broadband mirrors, are optical coatings designed to efficiently reflect or...

Spectral power distribution representing a standard source of illumination, which may be real or hypothetical.

The effect produced on a wave frequency because of the relative motion of a source or an observer. The radiation emitted...

The measurement of first- and higher order properties of a lens and its formed image, including effective focal length, back...

The area closest to an aperture or source where the diffraction pattern differs substantially from that observed at an...

An optical device that permits the alignment of a gun, cannon or rocket launcher system with its target.

A variation from standard physical vapor deposition (PVD) coating techniques, magnetron sputtering is a plasma coating...

See plane-polarized light; polarization.

A type of laser welding of thin materials using a defocused or low-power carbon dioxide laser beam. The energy is absorbed...

Infrared optics refer to optical components and systems designed to manipulate and control infrared (IR) light, which lies...

A device used to detect elevation, pyramid and resolution errors in prisms and other components by bringing them into...

An optical system that rapidly alternates two similar pictures or scenes to permit the detection of small dissimilarities...

With respect to television, that part of a color television circuit that combines the I, Q and Y signals, and changes them...

A resonator is a device or system that exhibits resonance, which is a phenomenon that occurs when an external force or...

A technique for polishing silicon in which an alkaline suspension containing silicon dioxide particles creates a soft layer...

The light flash, produced in flash photolysis, that is triggered within a second discharge tube by the third electrode. It...

An instrument for measuring the intensity of solar radiation.

A statistical method of dealing with a series of values where each value is squared, the sum of these squares is calculated...

An immersion liquid used to treat polarizing filters to eliminate the effects of surface variations and to minimize the...

1. A device used in chemistry to compare the colors of solutions held in flat-bottomed tubes and viewed along the length of...

An electromagnetic wave lying within the region of the frequency spectrum that is between about 1000 MHz (1 GHz) and 100,000...

The pressure or stress of one newton per square meter.

The total radiation, both solar and diffuse sky, that is incident to a unit's horizontal surface.

A chamfer ground on the edge of a lens or prism. Bevels are used to prevent chipping or to achieve a mechanical fit.

The correlation of radiation between the phases of monochromatic radiation emanating from two separate points.

The successive analysis or synthesizing of the light values or other similar characteristics of the components of a picture...

Also known as gatling gun laser. A system that has an array of lasers sharing a common central axis on a rotating Fabry...

An InGaAs photodiode refers to a photodetector device that is constructed using a semiconductor material composed of a...

A CubeSat is a type of miniaturized satellite characterized by its standardized size and modular design. CubeSats are...

An image-enhancement technique in which each pixel is subjected to a mathematical operation that groups it with its nearest...

A semicircular, half-wave quartz plate between the polarizer and analyzer. It often is used in forming precision settings...

A thermometric instrument used for the detection and measurement of radiant energy. Its essential component is a short...

CoaXPress (CoaXPress or CXP) is a standardized digital interface and communication protocol used primarily in machine vision...

A crystalline-quartz plate designed according to specifications but having its two major faces parallel.

Spherical aberration is an optical aberration that occurs when light rays passing through a lens or curved optical surface...

A quantum cascade laser (QCL) is a type of semiconductor laser that operates based on the principles of quantum mechanics....

A combination of components arranged so as to perform at least one function.

A process used to control thickness and parallelism precisely during the production of plane-parallel plates. Elements are...

Microscopic investigation of two-dimensional areas of a three-dimensional object that can be quantitatively evaluated by...

Geometrical partition possible with a sphere that can be four, six, eight, 12 or 20 solid-angle wedges. Each platonic mass...

Radiation emitted by electrons when they travel in circular orbits at speeds close to that of light. Synchrotron radiation...

1. In optics, the bending of rays away from each other. 2. In lasers, the spreading of a laser beam with increased distance...

A two-mirror lens design used in astronomical telescopes, the primary being a parabola, the secondary a smaller hyperbola....

A mode of data transmission whereby each bit of information is generated separately, with some stop/start code to indicate...

1. In a photonic interconnect, the number of detectors in a given area. Detectors spaced too closely may give rise to...

In cosmology, a star that exhibits a rapid increase in the magnitude of light, which is followed by a slow decrease in...

A fiber optic cable assembly refers to a complete unit consisting of optical fibers, connectors, protective jackets, and...

A factor of an equation of the Faraday effect, which is the rotation of the plane of light polarization by transparent...

Unit of illuminance equal to one lumen per square foot. (fc).

A micro-ring resonator is a compact optical device that utilizes the resonant behavior of light within a small ring-shaped...

One of a class of crystalline substances belonging to triclinic, monoclinic and orthorhombic systems that have two optic...

A filter that separates light into many colors via Bragg's law. Generally refers to a fiber Bragg grating used in optical...

Characteristic of the relationship between photoelectric activity and the wavelength of incident radiation.

An apparatus used to determine the degree of adaptation of the eye under different conditions.

Lens aberration resulting in image size variation as a function of wavelength. See also chromatic aberration.

The power, expressed in prism diopters, that is the linear displacement, in centimeters, produced by the prism one meter...

In local area networking, arrangement of the satellite nodes around a central node through which all routing of network data...

A small low-power microscope or magnifier with a scale that is used to measure the exit pupil diameter and eye relief on...

A double block formed by placing two adjoining, equally thick sections of quartz, one being dextrorotary, the other...

An instrument used to print an optical image on a specially treated paper. Light and dark portions of the original image are...

Fluorescence imaging technique in which the excitation light from the objective is directed into the sample producing...

A measurement in optical thin-film coating processes whereby the gases remaining in the vacuum chamber after coating are...

The determination of a substance's identity or quantity through the analysis of its optical rotation. For example, the...

A wave that is polarized elliptically or circularly polarized and in which the electric field vector — observed while...

The element that resembles a lightweight metal, but when very pure, has a very high electrical resistance and is transparent...

1. Calculated distance between two exactly opposed points on a beam at a chosen fraction of peak power (typically 1/e2). 2....

In an optical waveguide,- typically a multimode fiber - the distortion resulting from differential mode delay, i.e. axial...

The graph of the oscillating variations making up a wave, relative to time.

MicroRNAs (miRNAs) are a class of small, single-stranded RNA molecules, typically consisting of about 19 to 24 nucleotides,...

An ion carrying a positive charge and thus attracted to the cathode during electrolysis.

A complicated constant linked with the electron theory of the Faraday and Kerr effect. It demonstrates a specific value for...

1. To center an image or place it in any part of the television screen desired. Also applies to stills. 2. A single image of...

A holographic camera, also known as a holographic imaging system or holographic recorder, is a specialized device used to...

The effect in which photons are absorbed and excite the electrons; the electrons move from the valence band to the...

In a thermal imaging system, the smallest change in blackbody equivalent temperature that can be detected clearly by the...

The number of fields scanned per second in a television system. The US standard is 60. Also called field frequency.

A tank with a boiling solvent at the bottom and a ring of cold piping higher up that condenses the liquid and returns it to...

A device used to scan, with a small, intensely bright spot, portions of a picture surface and to transform the original...

A paraxial light ray that extends from an object point on the optical axis.

A filter that polarizes light passing through it. It is possible to fabricate sheets of plastic or gelatin that contain...

A thermistor that uses a semiconductor that is sensitive to infrared radiation to measure the radiation's intensity.

A negatively charged elementary particle. See electron.

A photometer having a pair of Nicol prisms introduced into the beam from the brighter of two sources to be compared. Turning...

A device used for the comparison of spectra used, in turn, for the comparison of elements, such as the absorption lines in...

A printing process of electrostatic electrophotography that uses a photoconductive insulating medium, in conjunction with...

Lens testing equipment refers to a range of specialized tools and instruments used to evaluate the optical performance,...

The maximum aperture of a lens at which it will still give a sharp image, even though its physical aperture may be larger.

A system that uses the heat from a pulsed laser to weld metals. Because of the rapidity and localization in which the...

Single-molecule Förster resonance energy transfer (smFRET) is a specialized technique in biophysics and molecular...

A group of four cameras loaded with different combinations of filters and film (one is usually an infrared color film) to...

Horizontal concentrations that comprise the dominant factor in atmospheric gradient correction. The range bias near due...

Pushbroom scanning is a technique used in remote sensing and imaging systems, particularly in satellite and aerial sensors,...

A cathode-ray tube that either splits an electron beam from one source or uses beams from two sources to produce two beams,...

In the context of imaging, particularly digital imaging and printing, "orange peel" refers to a texture or visual distortion...

A filter purposely made to be placed before a lens to render the image rather unclear.

An instrument for determining the sensitivity of a photographic film to light. The film is given either a stepped exposure...

coma, fifth order aberration with on-axis focal point variation with incident off axis ray height position

Secondary aberrations remaining after the primary (Seidel) aberrations have been corrected.

A Michelson-type interference microscope used to produce interference patterns of reflective specimens through the...

Seidel aberrations refer to a set of monochromatic aberrations in optical systems, named after the German mathematician and...

Unit of luminance equal to 1/p candela per square foot. (fl).

Also known as a white-light interferometer. Measures surface texture and shape from nanometer-scale roughness to...

Entirely analogous to color photography, but inclusive of light bands that do not appear in the visible spectrum.

The ratio of reflected flux to incident flux. Unless otherwise specified, the total reflectance is meant; it is sometimes...

The ability of a machine to perform certain complex functions normally associated with human intelligence, such as judgment,...

For light incident on a plane boundary between two regions having different refractive indices, the angle of incidence at...

A circuit whose passive components are deposited on a given substrate by sputtering or vacuum processes.

Laws that predict the maximum power output as a function of tube diameter for a hydrogen cyanide laser of a given discharge...

A telescope in which a mask occults the solar disk, generating an artificial eclipse and allowing observation and recording...

1. A faint second image caused by reflection that is sometimes seen when observing through an optical instrument. 2. With...

Ratio of the molecular diffusion coefficients of momentum in terms of heat; used in convection studies.

The study of the physics of x-rays, where the x-rays exhibit properties similar to those of lightwaves. Also called Roentgen...

The quality of asymmetrical intensity distribution in a laser beam, as opposed to a circular distribution.

Hyperchromic shift refers to an increase in the absorption of light, leading to a higher absorbance, often observed in...

Noise generated by the random variations in the number and velocity of the electrons from an emitter.

A material, such as gold black and carbon black, that is used as a solar absorber because of its high absorptance and low...

A polarizing prism assembly made up of two cemented calcite halves. The prism transmits the ordinary ray without deviation,...

An optical testing instrument is a device or system used to evaluate and measure the performance, quality, and...

The emission of gas or de-aeration due to thermal variations and often occurring in a vacuum. In a cleanroom, contamination...

Digital Imaging and Communications in Medicine (DICOM) is an international standard for medical imaging created by both the...

Synonym (regarded by some as erroneous) for multimode distortion, which see.

A lens aberration in which the focal length varies radially outward from the center of the field. It has the effect of...

An interference microscope that uses a light beam originating from a low-coherence light source. The sample is placed in one...

A false image in television that follows the desired image so closely that it appears to be smeared.

In a camera or cathode-ray tube, distortion that is designated by a lateral skewing of the reproduced image.

In optical character recognition, the mechanical or electronic transducer used to detect the level of illumination present...

The series of images formed when periodic objects are exposed to collimated monochromatic radiation and that result from...

The thin, transparent film made up of specific substances applied to glass-air surfaces for the purpose of decreasing the...

An erasable data recording and storage medium that uses a laser to heat the crystalline surface of the disc to a certain...

Laser drift typically refers to a phenomenon where the frequency or wavelength of a laser source gradually changes over...

The signal-to-noise ratio (SNR) obtained with a Fourier transform spectrometer when detector noise prevails, which exceeds...

The pattern formed by a character generation cathode-ray tube system, in which the characters are composed of a sequence of...

Also known as constant angle or constant deviation fringes. The interference fringes observed with dense flat plates near...

Laser lithotripsy is a medical procedure that uses laser energy to break down or fragment stones in various parts of the...

The use of a variable transmission filter at the aperture stop of a lens to modify its diffraction pattern. Reduced...

A corner cube, also known as a corner reflector or retroreflector prism, is a type of optical device used to reflect light...

A collection of color samples arranged in charts according to equal visually spaced steps in Munsell hue, value and chroma.

A Risley prism, also known as a Risley prism pair or Risley rotating prism, is an optical device used for controlling the...

Low-insertion-loss fiber coupler fabricated from a sheet of light-sensitive material laminated onto a fused quartz substrate...

Describes incident radiation propagating parallel to an externally applied magnetic field in magneto-optical experimentation.

A Mach-Zehnder interferometer is an optical device used to measure the phase difference between two collimated beams of...

Also known as RAMP microscopy, random access multiphoton microscopy is a microscopic technique that uses multiple...

A lamp that uses the transmission of an electric current through a gas or vapor to produce illumination. Neon, mercury and...

Pertaining to or as a function of wavelength. Spectral quantities are evaluated at a single wavelength.

A color whose hue is not produced by a single wavelength in the visible spectrum, but is instead produced by mixing the...

A center-opening shutter made up of several identical leaves that are mounted symmetrically around the optical axis of the...

A nonlinear label-free imaging technique commonly used during surgical procedures for the visualization of collagen fibers...

The positioning of two Nicol prisms so that their axes are at right angles to each other. With this arrangement, light...

A rare gas used in small high-pressure arc lamps to produce a high-intensity source of light closely resembling the color...

The standards of MIL-O-13830 set by the US government relative to tolerable surface scratches and other such defects in an...

A scanning electron microscope (SEM) is a powerful imaging instrument used in scientific research, materials...

Technique that uses high-pass filtering to reduce the local average to zero for all regions of the picture and then applies...

A low-power telescope placed at the eyepiece of an optical system to increase overall magnification. Most often used to...

A technique used in photogrammetry to ensure parallelism during projection printing. Failure to do this will change a...

The logarithmic method of determining emulsion speeds developed by the German standards organization, Deutscher...

The three lines in the spectrum of cadmium that have the purest radiations and that were first used by Michelson to...

Spatially offset Raman spectroscopy (SORS) is a technique that extends traditional Raman spectroscopy by incorporating...

A device small enough to be held in a hand that uses a magnifying lens and a translucent back to permit the viewing of...

A lens or lens system that produces an enlarged virtual image of an object placed near its front focal point.

A detector array refers to a collection of individual detector elements arranged in a two-dimensional grid or matrix format....

Plates of glass containing as many heavy metal oxides as can be dissolved in the glass without causing devitrification. The...

A method used in facsimile scanning that sweeps the elemental area across the copy in a spiral motion as the result of the...

A coil used to focus an electron beam by the generation of a magnetic field parallel to the beam.

The manifestation of light from scatterers outside the plane of the object in coherent light systems. The output of these...

The simultaneous occurrence of specular and diffuse reflection.

An acoustic wave that propagates along the surface of a solid and decays exponentially with substrate depth. Also called a...

A high-contrast transparency of the gas sought, or an array of exit slits that correlates with some features of the...

A charge-injection device (CID) refers to a class of devices that manipulate and detect electrical charge within a...

Magnetorheological finishing (MRF) is a precision optics polishing technique used for shaping and finishing optical surfaces...

A polarizing prism formed from calcite that is like the Nicol prism but has the two parts divided by a thin air-film and cut...

A chart formed by a spectrograph; the record of the spectral range. See spectrograph.

A fiber used in conjunction with a source to excite the modes of another fiber in a particular fashion.

A form of dispersing prism, often used in monochromators, that consists of a common right-angle prism with a 30°...

A colorless, crystalline compound whose low refractive index (n = 1.38) makes it effective as a lens antireflection coating...

The photographic recording that uses ultraviolet radiation to irradiate the microscope sample being examined and to form an...

The grinding and polishing of rock samples, to a thickness of less than 0.05 mm, for study with petrographic microscopes....

Optical noise refers to undesirable fluctuations or disturbances in an optical signal that can affect the quality or...

A phenomenon that causes the details in an image to appear at a spatial frequency higher than that at which the contrast...

An evacuated bulb containing a tungsten filament that is heated by passing an electric current through it. In domestic light...

A crystalline ferroelectric material used primarily as a substrate and an active medium for thin-film optical modulators and...

A compound lens so constructed that its overall length is equal to or less than its effective focal length.

In microscopy, the measured distance between theoretical parallel lines that are drawn tangent to the particle profile and...

A refrigeration method based on the Peltier effect. When an electric current passes through a thermocouple of two dissimilar...

A blackbody source, often simply referred to as a blackbody, is a theoretical or practical physical object that absorbs all...

A photodetector composed of a semiconductor material whose responsive properties can be altered by the addition of...

Also known as corner-cube reflector or retrodirective reflector. Three reflecting surfaces, perpendicular to each other,...

Gallium nitride (GaN) is a compound made up of gallium (Ga) and nitrogen (N). It is a wide-bandgap semiconductor material...

Refers to the characteristic hue of the ocean according to the presence and concentration of specific minerals or...

Volumetric imaging refers to the capture, visualization, and analysis of three-dimensional (3D) information from a volume of...

The curved mark formed when, in the process of generating, a loose or coarse diamond particle from the generating tool...

A refractometer that has a greater resolving power than a standard refractometer, and that uses a pentagonal prism to split...

A spectroradiometer is a device used to measure the intensity of light at different wavelengths across the electromagnetic...

States that in interferometers in which the separation of the maxima is equal to the half-value width, a slight drop in...

A fish-eye lens designed to photograph cloud formations over the entire visible sky.

The section of crystal symmetry having only one-quarter of the greatest number of faces permitted by the crystal system of...

The simultaneous collection of two or more signals at a single location. In a digital computer, it refers to the number of...

Photonic crystals are artificial structures or materials designed to manipulate and control the flow of light in a manner...

An experimental lens used to produce interference fringes. A positive lens is cut into halves along its center, and the...

A crystal formed by covalent bonds that are generally highly directional by nature. The electric characteristics of these...

An electron tube that employs electromagnetic radiation to produce a visual replica of an image produced on its cathode....

A form of lens assembly used in a projection system to maximize efficiency and assure uniform illumination of the object...

A set of mirrors along a telescope's polar axis designed to redirect light to a fixed position without being affected by the...

Multiple, interconnected circuit elements, contained on or in a common substrate, that function as a unit and not separately.

Situation in which the observer requires fewer than three independent stimuli to make color matches. Dichromats require only...

The photographic recording of the heat radiation emitted from various points on the object as corresponding density...

An image that can be studied three-dimensionally through a pair of complementary color filters composed of two superimposed...

A system that uses a continuous-wave laser to measure the velocity of an object by focusing the laser beam on the object,...

A photometer that uses a wedge, marked to show its reduction of flux density, to make two light sources equal in intensity...

The arc formed when the rare gas xenon is excited electrically and emits a brilliant white light. Xenon is used to fill...

A form of an element that cannot demonstrate optical activity as a result of dextrogyrate and levogyrate effects that are...

In a laser, the voltage necessary to initiate electrical discharge, somewhat higher than that needed to sustain it.

A term referring to various processes for forming visible images outside of a camera to be photographed on ordinary film....

A figure of merit corresponding to the amount of light seen by a viewer through binoculars. A higher number indicates a...

A weight reducing method whereby material from the rear of a reflector is removed leaving a pattern of ribs normal to the...

The measure of departure from a flat surface, as applied to lenses; the reciprocal of radius. Applies to any surface,...

Information storage on a dielectric medium that represents the data as those spots on the medium having electrostatic...

All formulas that present the index of refraction as a function of a wavelength of electromagnetic radiation. Also called...

A metal tool used to grind lenses with loose abrasive (see diamond cutting tool). The functional surface of the lap is...

In imaging, the processing of pixel data in such a way that a group of pixels is analyzed at one time rather than one pixel...

An electrostatic device that uses an electric potential barrier to allow the transmittance of electrons at or above a set...

A mid-infrared camera is a type of imaging device designed to capture images in the mid-infrared (mid-IR) spectral range,...

Capable of transmitting light with little absorption and no appreciable scattering or diffusion.

A lack of resolution in a television image as a result of smear ghosts or an insufficiently high video-frequency response....

The method by which interferograms are produced.

Two formulas used in diffractometer analysis, the first giving the individual diffraction patterns of each aperture, the...

Scattering (other than material scattering) that is attributable to variations of geometry and index profile of the...

A diffraction grating with lines and grooves formed so as to concentrate the radiation of a particular wavelength into one...

One of various types of fluorescent screens used to detect x-ray radiation. Photographic film is mildly sensitive to x-rays,...

A dark red opaque material that is transparent to the infrared beyond 1 µm.

A device that is used to produce or analyze plane-polarized light. It may be a Nicol prism or some other form of calcite...

A category of systems designed to communicate a photo taken from the air (e.g., aircraft, balloon, satellite) to a ground...

A physical stop that is conjugate to the entrance pupil and is used primarily to reduce diffraction effects at longer...

A type of radiation detector designed to recognize nonlinear optical effects, such as the Raman effect, by means of a...

The formation of microimages for microreduction. The technique is used, for example, in the production of precision reticles...

The metal tube that maintains the optical components of a lens in proper relationship. Some lenses are mounted in metal...

The base used to hold an astronomical telescope. It may be either altazimuth, with horizontal and vertical axes of rotation,...

A lens similar to the Cooke triplet anastigmat, with the rear crown achromatized for improved coverage and definition. It is...

A solid with a structure that exhibits a basically symmetrical and geometrical arrangement. A crystal may already possess...

Minimum object distance, often abbreviated as MOD, refers to the closest distance at which a camera lens or optical system...

In astronomy, the main lobe of an antenna pattern that has a small angular extent in two mutually perpendicular directions....

A scattering photometer using scattered light in the solid angle 4.51+0 19° with respect to the forward direction, and...

A camera tube similar in design to the iconoscope. However, the image formed in the image iconoscope is projected on a...

1. A polariscope consisting of a Savart plate and a tourmaline plate analyzer, and used to produce parallel color fringes by...

The phenomenon whereby certain crystals exhibit spontaneous electric polarization. It is analogous with ferromagnetism.

Zone of laser operation in which the direct, reflected or scattered light exceeds the laser's MPE and (by ANSI standards)...

A linear computation or algorithm performed on a selected series in the form of an input signal that produces a new series...

A standard of luminous intensity evaluated as the luminous intensity of 1 cm2 of a blackbody at the melting point of...

An astronomical body that emits radiation concentrated by a strong magnetic field into two beams that rotate, giving a...

The restriction of wavefront error to within a quarter of a wavelength of a true spherical surface to assure essentially...

The formation of a picture or image in which the density gradients in a volume of flow are rendered visible. The image is...

A dome-shaped structure used for some optical instruments in place of a flat window. The transparent material should be of...

A device used in measuring attenuation in optical fiber. The loss caused by the bends in a short reference length of fiber...

A semiconductor diode operating in either a coherent or incoherent mode that is used as a near-infrared or visible source in...

A compact high-pressure light source in which an electrical discharge between electrodes spaced no more than 12 mm apart...

The central wavelength range of a transmitter based on the worst-case scenarios of temperature, manufacturing and other...

Ion-beam sputtering (IBS) is a physical vapor deposition (PVD) technique used for depositing thin films onto substrates. It...

Having coincident focal points.

A pair of waveguides with axes normal to the plane and that guide uniform cylindrical waves.

A transparent block shaped accurately to reverse curvatures of the components it is used to test. By contacting an...

The conduction of electricity in a gas as a result of the ions generated by collisions between electrons and gas molecules.

Scanning electron microscopy (SEM) is an advanced imaging technique used in microscopy to obtain high-resolution,...

A two-mirror corrector for a parabolic primary mirror that provides anastigmatic performance for large astronomical...

A standard direct-readout vidicon tube linked by fiber optics to an intensifier for increased sensitivity.

A type of compensator for use with a microscope and consisting of a quarter-wave plate in a fixed position and a rotatable...

The procedure by which the similarity of an optical signal or waveform to a reference-stored signal or waveform is...

A type of exposure meter that artificially reduces the light admitted in a sequence of known fractions until a value is...

The process whereby blanks are attached to a block in a position for grinding or polishing.

In an optical waveguide, that dispersion attributable to the variation of refractive index profile with wavelength. The...

The intermolecular attraction between two surfaces, as between a substrate and a coating; it is an important factor in the...

The process whereby a quantum mechanical system alters from one energy level to another. During this process, energy is...

The measurement of heat energy as determined from absolute zero as the zero point on the scale. Increments are identical to...

A laser having a lasing material that is a fluorescing organic dye. Depending on the dye used, it can produce emission in...

The term gradient-index profile refers to a specific type of refractive index distribution within an optical material. In...

1. The negative electrode of a device in an electrical circuit. 2. The positive electrode of a primary cell or storage...

Radiation in which every ray from any given object point can be considered to be parallel to every other. This is never...

A plate of electro-optical material that serves to rotate the plane of polarization of a light beam.

The loss of focus of a camera sensor because of excessive brightness, characterized by the enlargement of spot size and...

Devices in which the lasing medium is a vapor of metal atoms or ions, sometimes mixed with another gas. Metal vapor lasers...

The production of an image on a magnetic film that is exposed to infrared radiation and heated to a point above Curie...

A filter that is transparent to shorter wavelengths, but opaque to longer wavelengths.

A monatomic, chemically inert gas such as argon, neon, krypton and xenon.

A ruggedized scintillation counter used in oil well logging. The cylindrical housing contains a gamma ray source, a...

Reflectance spectroscopy is a technique used to analyze the reflective properties of materials across various wavelengths of...

The total luminous flux given out per unit area; i.e., the sum of the luminous emittance and any radiation that is reflected...

A television system used for seeing in the dark, particularly with the use of infrared rays.

A spatial light modulator consisting of a metallized polymer film stretched over an array of metal-oxide semiconductor...

A rapid roughing process for the quick removal of glass, the first step in manufacture of a curved lens surface. It is...

A reticle pattern in a surveying instrument consisting of parallel lines that can be superimposed on a calibrated rod,...

E.I. duPont's trade name for a material used in the jacket of fiber optic cables. It is flame-retardant, thermally stable...

A flowmeter is a device used to measure the flow rate or quantity of a fluid passing through a particular point in a system....

A small xenon-filled tube with metal electrodes fused into the ends. The gas flashes brilliantly when a condenser is...

Flow cytometry is a powerful technique used in biology and medicine for the quantitative analysis of the physical and...

Lidar, short for light detection and ranging, is a remote sensing technology that uses laser light to measure distances and...

The Golgi staining technique (also called the black reaction) makes it possible to look at the nervous system by rendering...

A mercury vapor discharge lamp that has cadmium added to emit radiation in the red region as a complement to the mercury...

A pixel-based computer graphics system that simulates the tools of an artist.

A hologram in which the image of an object, or the object itself, is located near the hologram recording plane, for optimum...

The analysis of the properties of radiation, such as light, when acted upon by variations in the atmosphere. Blue and red...

A reflector that exhibits specular reflectance, producing a direct image of its source. Also known as regular reflectance.

A variable focal length lens system that retains the object in focus as one or more lenses move as a unit along its optical...

Immunohistochemistry (IHC) is a method for detecting antigens or haptens in cells of a tissue section by using labeled...

With respect to pictorial displays, the ratio of the width to the height. The television standard in the US is 4:3....

A device for converting sunlight into electrical energy, consisting of a sandwich of P-type and N-type semiconducting...

The analysis of fluorescence emitted by discrete atoms, in flames, that have absorbed radiation from an external source. It...

The indistinct rainbow that may sometimes be observed outside the distinct primary bow and that has its colors in opposite...

The study of the transmission of radiant energy through crystals, especially anisotropic crystals, and their effects on...

A low-power magnifier that usually has a large diameter.

A fluid having three components: a carrier fluid, magnetite particles suspended by Brownian motion and a stabilizer to...

A multilayer antireflective thin-film coating, so called because its reflectance rises steeply at wavelengths above and...

Eye blink or head movement in response to bright light. Aversion responses such as blinking are sufficient protection from...

The visual perception of motion when fixed stimuli are exposed in rapid temporal and spatial succession.

Attosecond photonics sources refer to devices or systems that generate extremely short pulses of light on the order of...

Meta-optics, also known as metasurface optics or flat optics, is a branch of optics that involves the design, fabrication,...

An approximated measure of the smallest change in color temperature detectable by the human eye, defined as the reciprocal...

A color filter, generally used in photography, to emphasize certain color tones and to modify others in a picture for a more...

A device used in measuring the attenuation of multimode optical fibers. A short reference length of fiber when combined with...

A disc composed of a series of holographic optical elements that diffract light at various angles. When spinning, a raster...

An absorption peak refers to a sharp increase or spike in the absorption of electromagnetic radiation at a particular...

Any system of time measurement that is based on atomic resonances. The transition times between the hyperfine levels of...

An electro-optical infrared tracker consisting of a beamsplitter, an illuminating source, an image dissector tube and an...

Any of the various methods of decomposing a signal into a set of coefficients of orthogonal waveforms (trigonometric...

A solar cell that uses a thermoelectric converter, consisting of two sheets of metal with a semiconductor sandwiched between...

Any of the photoelectric and thermal detectors, spectrographs and monochromators, thermographs, scanners, amplifier tubes,...

A quadrivalent semiconductor material, with electrons as the majority charge carriers, that is formed by doping with donor...

That part of a magnetic or optical tape or disc drive that retrieves data from or records data on the recording media.

Any structure having the ability to guide the flow of radiant energy along a path parallel to its axis and to contain the...

In image processing, the effect caused by large jumps between gray levels, rather than a gradual change.

The use of a specialized optical microscope designed to provide a more three-dimensional view of a sample. Stereomicroscopy...

A local area network topology in which all nodes are tapped off a single cable, and all hear every transmission on the cable.

The physical center of the lens; it is on the axis of the lens, halfway between the front and rear vertex. It is sometimes...

The electrostatic field acting locally within a crystal as a result of the microscopic arrangement of atoms and ions in the...

The ability of an optical system to make an object appear larger. An optical element or optical system causing an object to...

In a dual-ring local area network, a node that is connected both to the primary, active ring and also to a secondary ring...

An oven or furnace that possesses the design requirements and heat control necessary to anneal glass for the optical...

1. A constituent part. It may consist of two or more parts cemented together, or with near and approximately matching...

A lens that is symmetrical and designed to work between 1:1 and about 4:1. It covers a field of about ±20° at f/8...

The photographic recording of gas bubbles produced when particles traverse liquid hydrogen in a bubble chamber.

A process for the production of optical fibers. A glass bait is rotated in a traversing flame of a reaction burner....

The characteristics of a material that determine its tendency to flow.

A contraction of binary digit; the fundamental unit of digital computing, a bit is either 1 or 0, expressing the binary...

A unit of pressure, one-thousandth of a bar, equivalent to 100 Pascal and 0.75 torr. One atmosphere equals 1013 mbar.

Topological photonics is a branch of physics and optics that explores the application of topological concepts to the...

1. A lens situated at or near the plane of an internal image to project the aperture of a previous objective or erector upon...

The use of a short-duration electron beam to record high-speed events that occur in microscopic objects made of materials...

Lithography is a key process used in microfabrication and semiconductor manufacturing to create intricate patterns on the...

A laser system consisting of a planar PN junction within a single crystal of gallium arsenide. The pair of parallel,...

In computer graphics, the coordinated two-dimensional or three-dimensional area of increased resolution where graphics...

A photomask, also known simply as a mask or reticle, is a key component in the photolithography process used in...

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light...

A law that uses the square of the cosine between the plane of polarization of a beam of plane-polarized light and the plane...

Photochromic refers to a property exhibited by certain materials, typically organic compounds or dyes, which undergo...

Turbidity is a measure of the cloudiness or haziness of a fluid caused by the presence of suspended particles. These...

An image that is formed when rays emerging from an optical system are diverging from the optical axis. The virtual image is...

A microbubble resonator is a device used in photonics and optical physics for the precise manipulation of light waves. It...

A device for measuring absorption coefficients in which a confined, nonabsorbing gas fills the space inside the cell between...

A defect of natural quartz crystals in which both the right and left quartz are in the same crystal.

The ratio of aperture area over receiving area for a specific lens. Also called geometric concentration.

A Peltier cooler, also known as a thermoelectric cooler (TEC) or thermoelectric module, is a solid-state device that uses...

A substance that transmits the infrared, but which is too delicate or fragile to be used in the form of a single crystal....

The law given by the formula: that is, the frequency of radiation emitted or absorbed by a system when E2 and E1...

A colorimeter using a spinning disc made of different colored sections for colorimetric analysis.

Thermophotovoltaic (TPV) refers to a technology that converts heat energy into electricity using the principles of...

The study and photographing of microscope specimens in ultraviolet light; using an optical microscope containing fluorite...

A thin-film device containing miniature optical components connected via optical waveguides on a transparent dielectric...

A crystal having the axes of its grains aligned so that they have directional magnetic characteristics.

A subsurface imaging technique based upon the polarization of light reflected off an object. The polarization of reflected...

Flux per unit solid angle and per unit area measured normal to the direction of propagation of the flux.

The degree to which a pixel in a digital image represents the analog brightness of the corresponding point in the original...

That contrast level that exists between two areas whose difference in brightness is just perceivable.

The lowest anode voltage at which a gas tube can sustain a discharge.

Photometry is the branch of science that deals with the measurement of light, particularly in terms of its intensity and the...

Positioning generally refers to the determination or identification of the location or placement of an object, person, or...

The process of subjecting glass to temperature cycling to produce physico-chemical reactions that alter its properties....

The coefficient Å in Angstrom's formula for the dispersing coefficient for dust present in the atmosphere. The formula...

A nonoptical surface, within lenses and lens mounts, that contributes largely to flare by reflecting light into the image...

An assembly of fibers in which the coordinates of each fiber are the same at the two ends of the bundle. Also called...

In optics, the term denoting the lack of a fixed phase relationship between two waves. If two incoherent waves are...

Ultraviolet-C (UV-C) refers to a specific range of ultraviolet radiation with shorter wavelengths than those of visible...

A photoelectric detector consisting of a glass tube internally coated with a low conductance material. Voltage applied along...

Piezoresistance is a phenomenon in materials science and physics where the electrical resistance of a material changes in...

In the optical field, a piece of glass to which a lens or prism is cemented. The unit is ground and polished as a whole to...

A telescope similar to the customary Cassegrain telescope, but having a primary mirror that is ellipsoidal and a secondary...

Any of the numerous powders used for grinding and polishing glass, crystal or metal, the chief material being emery and...

In optics and photolithography, a phase mask refers to a device that modifies the phase of light waves passing through it....

A computer whose architecture contains several CPU chips arranged in parallel. Often used in image processing systems.

A term for the ring-shaped stop in a phase contrast microscope. The phase annulus limits the amount of light that reaches...

A grating beamsplitter is an optical device that utilizes the principles of diffraction to split a beam of light into...

The angular difference in the direction of an object as seen from two points of observation. The angle subtended at the...

A type of glass used in telescope mirrors, formed by adding a nucleating agent to standard glass and then heating it until...

An exciton is a quasiparticle that represents the bound state of an electron and a hole in a solid-state material, typically...

The movement of an object seen through a refracting prism toward the apex of a prism.

Machinery used to grind and finish a component, such as a lens or prism, to a desired precision. Usually such machines carry...

The degree to which a pair of fine lines can be aligned to each other. A normal observer will demonstrate an accuracy of 10...

Metamaterials are artificial materials engineered to have properties not found in naturally occurring substances. These...

A method of studying the chemical and physical properties of atoms and molecules (typically living tissue and chemical...

Rare-earth elements (REEs) are a group of seventeen chemical elements found in the Earth's crust, characterized by their...

The spectrum of the light produced by vaporizing an element in an electric arc.

The use of a krypton laser system for the measurement of small molecules aligned by an electric field, by analyzing the...

Translucent collector developed to compensate for the partial blocking of a flat surface's collection angle that normally...

Radiation that is emitted by a source outside the Earth and its atmosphere.

An optical filter so constructed that the density increases progressively from one end to the other, or angularly around a...

One of the four functions that allows the computation of a transparent medium's index of refraction, provided the index has...

A field of physics that deals with light as if it truly were composed of rays diverging in various directions from the...

A high-speed network or subnetwork that provides a connection between servers and data storage devices.

The internet of things (IoT) refers to a network of interconnected physical devices, vehicles, appliances, and other objects...

A laser that generates a succession of pulses at a high enough repetition rate to appear continuous. The pump source is...

An aperture consisting of a semitransparent central region whose amplitude transmittance only is varied, and the relative...

An intensified charge-coupled device that uses a large negative charge at the grid to switch off the flow of electrons at...

A stroboscopelike apparatus that uses a copper vapor laser to illuminate an object for very short time periods (about 30 ns).

A ray that behaves according to paraxial equations; one that lies close to and almost parallel to the optical axis.

Gallium nitride-based light-emitting diodes (GaN-based LEDs) are semiconductor devices that emit light when an electric...

In television, a lateral displacement of the lines from their normal position due to the instability of a synchronizing...

Multimode straight fiber capable of transporting linearly polarized light with any incident polarization angle, and in which...

A neuromorphic vision sensor is a type of imaging device designed to mimic the structure and functioning of the human visual...

1. With respect to angular subtense, a source of light, such as a star, that is very small. In a lab, a point source may be...

A crystal that is devoid of any mosaic structure and that can reflect x-rays, relative to the Darwin-Ewald-Prins law.

Production of a repeated image of a transmitted beam through a diffractive optical element such as a holographic card or...

The transparent fluid that fills the portion of the eye between the cornea and the eye lens (the anterior chamber).

Pockels cell or dynamic optical retarder in which the electrical field is applied in a direction parallel to that of light...

A very hard, highly transparent coating based on forms of carbon, used to protect optical components from abrasion and...

The ionization and spark emission due to exposure to ultraviolet radiation.

(SALI) A type of spectroscopy in which neutral atoms or molecules are ionized by an excimer laser beam and then measured by...

A hollow sphere coated internally with a white diffusing material and provided with openings for incident beam, specimen and...

The electrical power used to stimulate any light source. Power supplies may be step-up or step-down transformers; rectifiers...

A Dammann grating is a type of diffractive optical element (DOE) used to create an array of equally spaced,...

A long-pass filter is an optical filter that allows longer wavelengths of light to pass through while blocking or...

A method of designing lasers whereby the laser rod is cut into elliptical discs and cooled by running water over the disc...

An exaggerated depth appearance in stereo photographs caused by the lenses in the camera being farther apart than the eyes...

Fiber optic cable in which the arrangement of fibers within the bundle has been made random so that output light will be...

A technique used in photolithography of computer chips to compensate for errors caused by the proximity effect, which...

The green line, in the spectrum of the aurora borealis, that has a wavelength of 5577 Å; it is caused by a forbidden...

A gas, such as oxygen, that improves the speed and efficiency of a laser cutter or welder when applied to the work surface,...

The relation of power between center peak longitudinal mode with the nearest higher order mode.

A visual, single-unit spectrophotometer with a biprism and a Wollaston prism. The Wollaston prism polarizes coincident...

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two...

A charge-coupled device (CCD) is a type of electronic image sensor used in various imaging devices, including digital...

Mechanical device intended for the translation (rotational and linear) using high precision control from electronically...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic...

A form of roof prism used to invert an image. The prism has faces cut normal to the optical axis; therefore, the prism may...

The slits in a spectrograph that form images of spectral lines. Slits may be bilateral or unilateral, and generally close...

A device used to project a reference spectrum next to a spectrum to be analyzed to provide visual comparison.

The number of unique ways in which a part can move in an alignment system. In static alignment, there are six: one in the...

A camera designed to record astronomical objects (e.g., stars, planets, nebulae, galaxies) and their spectra.

Spectra can be conveniently recorded on photographic film or plates. The portions that are occupied by regions of the...

An instrument that uses a beam of light to scan a color transparency, and three differently filtered photosensors to record...

A device having a plane mirror so mounted that it can be set to reflect sunlight into a piece of laboratory equipment. It is...

The term delta error (delta-E) generally refers to the difference or change in error between two values or states. The word...

Enhanced picture archiving and communication system (PACS) display (ePAD) is a software tool used in medical imaging to...

Pertaining to the possession of photoelectric characteristics as a result of the properties of the true crystal and not of...

A saturated compound of carbon and hydrogen used as a liquid coating material for optical components in high-power laser...

Also called DLIP, a high-speed, high-resolution processing technique that uses high-power, pulsed laser systems to directly...

Also referred to as the axial ray (or a-ray), a marginal ray originates from the axial point of the object and passes...

In the spectral sense, an optical source that emits one or more spectrally narrow lines as opposed to a continuous spectrum....

Phase matching is a crucial concept in the field of optics, particularly in nonlinear optics and the generation of coherent...

Digital signal processing (DSP) refers to the manipulation and analysis of signals, which are representations of physical...

With respect to display systems, a device that uses an independent light source and a control-layer medium, the active...

Pyramid error in optics refers to an aberration in the shape of an optical surface, particularly in the context of mirrors....

A filter that passes a series of wavelength regions that are at equal distances from one another, such that its output...

Flux incident per unit area of a surface.

A unit of measurement of luminous intensity based on a physical standard, a set of calibrated carbon filament lamps. The old...

A naturally occurring crystalline mineral that has the property of polarizing transmitted light. It is little used now that...

Direct conversion of a photon from one wavelength to a lower energy photon of another wavelength(s) due to inelastic...

A line-scan camera, also known as a line-scan image sensor or linear array camera, is a type of digital camera designed to...

Light-absorbing material that is applied to the back support of any bright image under inspection to prevent the formation...

A narrow cone of light rays that diverge from a point source or converge to an image point.

The plane shared by the pair of axes in a twin crystal.

An optical fiber, usually a single-mode fiber, that has an outer cladding with nearly the same index of refraction as the...

Fine lines, wires or threads used in the focal plane of many optical instruments to point out and locate particular objects...

This type of miniaturized system, referred to as CMOS qPCR, combines microfluidic technology with an ultralow-light CMOS...

The scanning of a region in a given sequence of slender, straight parallel strips.

A semiconductor made up of two or more elements, in contrast to those composed of a single element such as germanium or...

Flux per unit area measured normal to the direction of propagation of the flux.

The pressure in the gas region of an x-ray tube that has been reduced below 0.1 mm, the pressure necessary for the tube.

See crystal quartz; fused quartz.

Scientific complementary metal-oxide semiconductor (sCMOS) refers to a type of image sensor technology specifically designed...

A mirror mount is a mechanical device used to secure and precisely position mirrors in optical systems. Mirrors are...

Ink used for writing on glass, and also for blackening the edges of lenses to prevent reflection. In the latter case, the...

A precision positioning device used to produce rotary motion.

In the context of electronics and semiconductor manufacturing, a wafer refers to a thin, flat disk or substrate made of a...

The use of computer analysis in the calculation of diffraction patterns for information on the design of optical systems. In...

An instrument usually consisting of a very long interferometer, 3 to 800 m, and a laser light source for the study and...

A well plate, also known as a microplate or microtiter plate, is a flat plate with multiple small wells or depressions...

Reflectance confocal microscopy (RCM) is a non-invasive imaging technique that allows for high-resolution, in vivo imaging...

Characterizes a substance whose plane of polarization is rotated counterclockwise as the observer looks through the material...

An instrument designed to calculate the amplitude and phase of the different harmonic elements of a radiation wave utilizing...

Any object that emits radiation of a wavelength lying between about 0.75 to 1000 µm. A calibrated secondary source...

An instrument that is used to detect high-energy particles by the pulse of the current formed when a particle passes through...

A uniaxial, birefringent crystal having an ordinary ray with a higher velocity than the extraordinary ray.

Also referred to as image visibility, the contrast of an image is the variation in the intensity of an image formed by an...

A phenomenon, exploited for medical imaging, in which the nuclei of material placed in a strong magnetic field will absorb...

A kind of spectrograph in which some form of detector, other than a photographic film, is used to measure the distribution...

The range of image distances that corresponds to the range of object distances covered by the depth of field.

Tip-enhanced Raman scattering (TERS) is a powerful technique that combines Raman spectroscopy with the enhanced spatial...

A noncontact sensor used in the remote measurement of position, speed or other variables of moving parts.

The broadening of a laser's line width in a way that affects every atom (or molecule), and thus the whole system, in the...

The picture area scanned per second.

Ultraviolet (UV) fiber optics refers to optical fibers that are designed and optimized for the transmission of ultraviolet...

A fiber optic sensor is a device that uses optical fibers to detect and measure physical, chemical, biological, or...

The term light field refers to the spatial distribution of light rays traveling in all directions through a given space. It...

An image-processing device that scans in a straight line parallel to the axis of a rotating cylinder to which the material...

Similar to LASCR, except that all four regions are available.

Hardware installed on fiber cable ends to provide cable attachment to a transmitter, receiver or other cable. Usually a...

The imaging of two photographs of a stereo pair, in complementary colors, for the preparation of contour maps.

Infrared radiation emitted from a source that is not heated sufficiently to give off visible radiation.

A device through which scintillations are observed or counted through a magnifying lens system.

An electric arc that is formed in mercury vapor through which an electric current flows. The intensity of the illumination...

Array used in coded-aperture imaging experiments with two-beam CO2 lasers that provide an artifact-free process, faithful...

The minimum value of luminance for vision. The value may vary with age as well as dark adaption period. (Measured range...

The perception of visual stimuli at the left and right outer boundaries of the visual field.

Photosynthetically active radiation (PAR) is the 400- to 700-nm region (visible light) of the electromagnetic spectrum that...

The photographic recording, and later enlarging, of very thin specimens, using an electron beam to form the image.

Laser optics refers to a broad category of optical components and systems designed for manipulating and controlling laser...

A function that quantifies the performance degradation of coherent communications systems, imaging systems and all systems...

A particular type of phototube having increased sensitivity as a result of the glow initiated by light incident to the...

Piezoelectric transducers are devices that utilize the piezoelectric effect to convert electrical energy into mechanical...

An objective measure of an object's brightness that is derived from the ratio of the luminance of its lightest section to...

A method of producing large volumes of plastic optical components in which powdered or sheet plastic is pressed between...

The conversion of an internal latent image into a surface latent image through exposure to infrared radiation. The converse...

In a waveguide, the material in intimate contact with the cladding surface, applied to preserve the integrity of that...

Short wavelength infrared (SWIR) refers to the portion of the infrared spectrum that encompasses wavelengths roughly between...

An optical instrument that uses a yellow light of varying intensity with red and blue lights of fixed intensity to test for...

Subsurface linear arrangement of elements of rock that is not mappable; lineation is a one-dimensional characteristic.

An operate mode in which the sensor is programmed to perform a task such as generating output when the light level falls...

Oscillation in rod and disc amplifiers that critically limits the achievable energy storage.

A nonabsorbing, multireflecting device, similar in design to the Fabry-Perot interferometer, that serves as a multilayer,...

Measurement of absorption by the gas of interest in the 2- to 6-µm range as a function of tangent height pressure. The...

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating...

An imaging system designed to highlight small deviations in a planar reflective object such as a mirror. The system can be...

A device consisting of two optical systems in which two signals are simultaneously transformed to produce their spectra, and...

The small central portion of the human retina that is responsible for providing the clearest, and most distinct aspects of...

A negative lens used to increase the effective focal length of a telescope objective.

A device designed to decrease flux density or power per unit area of a light beam through absorption and scattering of the...

Micro-optical coherence tomography (micro-OCT) is an imaging technique that is an adaptation of optical coherence tomography...

The ability of the human eye to adjust itself to low levels of illumination.

A special evacuated camera equipped with means for holding a specimen and bombarding it with a sharply focused beam of...

A computer-generated kinoform used for data processing because of its use of incoherent light and its wide field of view,...

A microchannel plate (MCP) is a specialized electron multiplier device used in various applications such as particle...

The second adjustable iris diaphragm in an optical system. In the common microscope condenser system, it usually is located...

A Nernst glower, also known simply as a Nernst lamp or Nernst filament, is a type of incandescent lamp or radiant heater...

The use of chemicals or radiation to induce a desired change in a substance; e.g., some optical adhesives are set by...

A microlens array is a grid-like structure composed of numerous small lenses, typically arranged in a regular pattern. Each...

A plane in a crystal that lies parallel to the principal plane of symmetry.

A quantum dot is a nanoscale semiconductor structure, typically composed of materials like cadmium selenide or indium...

Area scan, in the context of imaging and cameras, refers to a method of capturing an entire two-dimensional image in a...

A high-brightness, short-duration source in which low-pressure gas initiates the discharge to vaporize material from the...

Frequently used in astronomical measurement, it is based on the diurnal rotation of a star relative to the fixed stellar...

A furnace used to heat glass materials. It may be a small laboratory-type furnace for small-scale experiments or large...

Machine vision lighting refers to the use of specific lighting techniques and equipment in the field of machine vision,...

A number that indicates the magnitude of the shift in a solid of positive and negative charges in opposite directions when a...

1. In optics, the ability of a lens system to reproduce the points, lines and surfaces in an object as separate entities in...

A means of determining a prism's index of refraction by placing the prism so that its emergent face is perpendicular to the...

A phenomenon that occurs in WDM and DWDM systems when three closely spaced signal wavelengths near the zero-dispersion...

The decrease in effect in developable density on a photographic plate formed by a second exposure to radiation having a...

A polariton is a quasiparticle resulting from the strong coupling between photons (light particles) and certain types of...

A television format with enhanced vertical resolution (400 lines as compared with the standard 330) that, unlike...

A binary semiconductor compound used as a substrate or active layer for diode lasers.

Luminous flux emitted from a surface per unit solid angle per unit of area, projected onto a plane normal to the direction...

That portion of physics concerned with motion in the abstract, such as of points or space figures, and separated from its...

A soft, malleable, stable rare-earth element. Holmium laser systems are used in surgical procedures involving the cutting...

Diamond turning refers to a precision machining process used to produce complex optical components, particularly lenses and...

The range of frequencies over which a particular instrument is designed to function within specified limits. See also fiber...

A method of analysis in which a pulsed laser beam is used to heat a particle, producing a plasma, or laser spark. As the...

Also known as integrated exposure. A measurement of light from sources that vary rapidly with time, defined as the integral...

Calculation of the probability of an interaction between two types of particles, such as light absorption, excitation or...

A mode in an optical waveguide whose fields are transversely oscillatory everywhere external to the waveguide. It exists...

A device that uses four electrodes set in an alternating positive-negative polarity series to focus the beams of charged...

A GaAlAs laser is a type of semiconductor laser diode that emits light in the near-infrared region of the electromagnetic...

A desklike apparatus with an opal glass surface illuminated from beneath by fluorescent tubes. It is equipped with roll...

Phase contrast microscopy is an optical microscopy technique that enhances the contrast of transparent and colorless...

The equation devised by Sir G.B. Airy for the analysis of light diffraction near a caustic surface: (d2f/dz2) - zf = 0 where...

X-rays of one frequency or a narrow band of frequencies.

The combination of the audio and visual signals that are transmitted and received at the same time, correlating the scene...

The generic term applied to all sources of visible radiation from burning matter to ionized vapors and lasers, regardless of...

A polariscope with a half-shade device and an angular scale generally attached to the analyzer. It is used to measure the...

Mie scattering, named after the German physicist Gustav Mie, refers to the scattering of electromagnetic radiation (such as...

A laser having a material, such as ruby, that has an energy state structure of three levels: the ground state (1) wherein...

The arrangement of two Porro prisms so that the inverted image formed by certain types of optical instruments is the same as...

A computerized token-passing local area network (LAN) configuration adopted by General Motors for real time control over the...

A photodetector, also known as a photosensor or photodiode, is a device that detects and converts light into an electrical...

A method of thin-film deposition in which electrons boiled off a heated cathode are used to melt the coating material. If a...

A process used in document copying and printing that involves the visible rendering of an invisible electrostatic image on a...

Histology is the branch of biology and medicine that involves the study of the microscopic structure of tissues and organs...

Technique in which the polarization rotation of light, and its relationship to the magnetic field strength can be analyzed...

Decrease in cosmic ray activity that is observed approximately 24 hours after a solar flare, attributed to a shielding...

A wave that changes from one amplitude to the other in a short time compared with the wavelength.

Light diffusion refers to the process by which light is scattered or spread out in various directions as it interacts with a...

An infrared source combined with reflecting projection optics to illuminate a target making it visible when observed through...

A laser device intended for crushing urinary tract stones so they can be flushed from the body. Light is introduced via...

Augmented reality (AR) is a technology that integrates digital information, typically in the form of computer-generated...

In image processing, the mathematical relationships that link pixel brightnesses of input images to those of output images...

Liquid marble refers to a unique form of microscale liquid encapsulation, where small droplets of liquid are coated with a...

A perfect diffuser that exists only as a concept, or a white with known spectral characteristics used as a reference in...

The partially reflective mirror at the end of the laser cavity that is the source of the beam. It controls the coupling...

A classification of particular regularities that occur in the spectra of many atoms.

A substrate refers to a material or surface upon which another material or process is applied or deposited. In various...

A guided missile that uses an infrared sensor to detect and home in on an enemy target. The missile is guided by the high...

A CMOS image sensor, short for complementary metal-oxide-semiconductor image sensor, is a type of semiconductor device used...

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials...

An antigen is any substance that is capable of triggering an immune response in an organism. Antigens are typically proteins...

The separate spectral lines formed by a diffraction grating that are characterized by one wavelength difference in path...

A pair of long, slender parallel apertures used in experiments on diffraction and interference.

Micro-robotics refers to the field of robotics that involves the design, development, and application of miniature robotic...

A piece of glass that eventually becomes the bifocal segment as it appears prior to being fused to the blank.

In image processing and elsewhere, generally an adjective to describe an assembly-line arrangement for performing a task....

Radiant flux incident per unit area of a surface. Also called radiant flux density.

A grating used as a reflectance filter, particularly in the far-infrared. Small plane gratings, blazed for the wavelength of...

A coating made up of many layers of material having alternating high and low refractive index. In this way, it is possible...

An instrument used to support optical parts to be cemented, or to be mounted in plaster.

A device where each pixel in the detector array is mated with a preamplifier on a single silicon chip, providing sensing and...

A device using a parametric amplifier inside a resonant optical cavity to generate a frequency-tunable coherent beam of...

SI unit of luminous intensity. It is defined as one sixtieth the normal intensity of one square centimeter of a blackbody at...

Also referred to as differential interference contrast (DIC) microscopy; Nomarski microscopy is a unique form of microscopy...

A polarizing beamsplitting prism similar in design to the Rochon prism. However, the Senarmont transmits the extraordinary...

The method of determining the energy distribution of high-speed charged particles by the luminous effect formed when the...

1. A measure of absorbed dose, equal to the energy imparted by ionizing radiation to a mass of matter corresponding to 1 J...

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor...

A mode of transmission whereby the sending and receiving stations operate continuously at a fixed relationship of phase and...

Optical coatings are thin layers of materials applied to optical components, such as lenses, mirrors, filters, and prisms,...

A semiconductor platelet laser that emits a coherent image by means of plane optical pumping over the platelet surface, and...

Fluorescence produced as a result of the intrinsic property of the material itself or the doping of the material with trace...

A unique glass made up of nano-structured materials to create millimeter sized monolithic glass space-variant polarization...

Postulated by Einstein in his theory of relativity. They are waves traveling at the speed of light and exerting force on...

Two stars so close together that they cannot be resolved by telescopes. They are proved to be double stars by the doubling...

The angular subtense of the field of view in the image space of a telescope, as differentiated from that in the object space...

A specified cold-cathode gas tube used to apply a short-duration, high-power arc for a stroboscope.

A device, such as a thermionic or crystal diode, that is introduced into the vision channel of a television receiver to...

The coupling of laser or light beams via nonlinear optical techniques such as four-wave mixing to achieve spatial variation...

A method that embraces the classical approach to image restoration and attempts to minimize the mean square difference...

A supporting member used to hold optical parts during grinding and polishing. It also describes the assemblage of optical...

A colorimetric concept related to the apparent visual color of a source (not its temperature). For a blackbody, the color...

A technique for measuring the concentration of any gases. Identical infrared beams are alternately chopped, one passing...

Förster resonance energy transfer (FRET) is a mechanism describing the transfer of energy between two closely spaced...

Optical materials refer to substances or compounds specifically chosen for their optical properties and used in the...

A glass substrate that has its rear surface coated with a reflective coating. Also known as a back-surface mirror.

A small instrument containing a picture support and a pair of magnifying lenses so arranged that the left eye sees only the...

A specific gas-filled tube designed to illustrate the luminous effects of discharges through rarefied gases.

The analysis of the atomic structure of a sample by means of a source radiation that is absorbed and emitted by the sample...

An image that appears when a hologram is illuminated by a suitable light source, generally a laser beam.

The maximum number of users who are using a given communication channel. Typically, the number of users at any given time is...

The removal of the zero-order component of the Fourier spectrum distribution of an object with a small, opaque absorber or...

Extended period exposure photographs of a laser light created with various patterns within full image (laser graffiti).

A thin-film photoconductive cell that is sensitive to the infrared region. The photosensitive material of the cell is...

A calorimetric calculation from which the temperature vs. time dependence of any point on a sample can be determined,...

A device having a pair of decentered lenses, one for each eye, that focuses on a single object as a magnifier. It is often...

A shaft, spindle or any object generally passed through a workpiece to hold, support or shape a particular piece during its...

A combination 80-column computer card containing a 35-mm microfilm frame. Reference data can be punched onto the card to...

Gas detection measurement technique that uses a built-in capacitative microphone to calculate the amount of absorbed laser...

1. The sector of the Earth's surface registered upon a remote sensing device in a satellite. 2. The amount of space occupied...

In the field of optics and imaging, a mesoscope refers to an optical instrument that is designed to observe and capture...

Potential hazards to a system's application and installation, including temperature variations, chemical reactivity,...

An atom that has gained or lost one or more electrons and, as a result, carries a negative or positive charge.

Also duty factor, duty ratio. The product of the pulse duration and the pulse repetition frequency of a wave composed of...

The time it takes a cathode-ray tube's electron beam to return to its starting point after completing one line, one field or...

A dichroic coating, also known as a dichroic filter or dichroic mirror, is an optical coating designed to selectively...

A measure of the dispersive properties of a glass. The relative dispersion is defined as: where C, D, and F refer to the...

Plasmon ion-assisted deposition (PIAD) is a technique used in thin-film deposition processes, particularly in the production...

The transparent component of an optical reader that transmits the image rays of the characters to be read.

Compilation of the Air Force Cambridge Research Laboratories that contains values of the line parameters of the 1-0 bands of...

A permanent, transparent, and highly transmissive adhesive capable of withstanding extreme temperatures that is applied to...

An incandescent or carbon arc lamp designed with a stable and compact arc or filament that permits it to be used as a light...

A molded lens is an optical lens manufactured using a molding process, typically involving the shaping of a material, such...

A nonluminous area around a negatively charged probe that is inserted into the positive column of an arc or glow discharge.

The region of distorted atom configuration formed between the displaced and normal areas in a crystal when part of the...

A device similar to the ordinary spectrophotometer but containing particular modifications to provide for the comparison of...

A photographic objective that uses the thick meniscus principle to obtain its power. It is designed to photograph small...

A digitized image consisting of just two brightness levels, as black and white, represented in memory as zeros and ones.

An accelerometer is a sensor or transducer that measures the rate of change of velocity of an object, or in simpler terms,...

In astronomy, the relation that states that the intensity of a star's visible radiation is inversely proportional to the...

In vitro is a Latin term that translates to "in glass." In scientific contexts, particularly in biology and medicine, it...

A process of color photography in which colors are added one to another in the form of light, rather than as colorants, to...

A chemical detection technique used to measure molecules that have a magnetic dipole moment. The analysis is directed to...

A part of the spectrochemical analysis of a sample that deals with the excitation of that sample by flame analysis.

Light diffracted by a solid (usually quartz in crystal or fused form) traversed by acoustic waves. If the ultrasonic...

Computer hardware or firmware that accesses character patterns stored in read-only memory and displays them at specific...

A reflecting optic whose reflectivity is a function of the radial distance from the optic axis; can be used to convert a...

A device that obliterates the polarization of a polarized beam by reflecting the beam in all directions at right angles to...

A mirror employed with a very high incidence angle to form a pair of coherent light sources by reflection, and therefore...

Quantum entanglement is a phenomenon in quantum mechanics where two or more particles become correlated to such an extent...

Image sensors in a two-dimensional configuration of rows or columns.

Laser annealing is a process that involves using a laser beam to heat and modify the microstructure of a material, typically...

A photographic emulsion of the silver-halide type that is used to record the path of a charged traveling particle. The...

A device that uses electromagnetic fields to separate electrically charged particles according to their masses. As a beam of...

An instrument that contains a spectrograph with a grating in which an array of slits, in place of a photographic plate, is...

In the context of optics and lasers, a transverse mode refers to a specific spatial pattern of the electric field within the...

The array of methods used in the transmission and reception of pictures and images with a three-dimensional appearance.

A calculated function that can be achieved experimentally with interferometric analysis of complex atmospheric altitude;...

A process by which the ionizing capabilities of a laser beam are used to break initiate conduction between pairs of...

Remote inspection refers to the process of inspecting, evaluating, or monitoring assets, equipment, infrastructure, or...

A study of the energies and wavelengths of radiation emitted by atoms and molecules when particular physical conditions are...

Resonance can be defined in various contexts, including physics, chemistry, and music. Here are definitions for resonance in...

The method for measuring the index profile of an optical fiber by preparing a thin sample that has its faces perpendicular...

Directional and coherent radiation pulses that result from an ensemble of coherently prepared states in an optical medium.

Term for service offered by a vendor who leases a particular wavelength to a customer through DWDM technology. Lambda...

The process of using a spectrograph with a telescope to acquire information on an astronomical object's speed and physical...

In image processing, a morphology operator in which a structuring element or probe of a particular shape is moved over the...

A support device in which a column or chamber of air permits the free travel of a mobile part. In optical mounting and...

1. The photosensitive membrane on the inside of the human eye. 2. A scanning mechanism in optical character generation.

A technique that uses a solid-state laser and a detector to determine an object's relative distance to the system. The laser...

In a charge-coupled device, the disappearance of some of the accumulated charge into the silicon during readout.

Optical character recognition (OCR) is a technology that is used to convert printed or handwritten text into...

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures changes in hemoglobin...

A diffraction grating is an optical component consisting of a surface with a periodic structure of equally spaced, parallel...

An optical fiber that can be used to amplify an optical input. Erbium rare earth ions are added to the fiber core material...

Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications...

A machine vision technique that compares a template of the desired image (the correlation kernel) with the actual camera...

For a lens with an obscured or noncircular aperture, the focal length divided by the effective aperture.

Chirped pulse amplification (CPA) is a technique used in laser physics to amplify ultrashort laser pulses to high energies...

In an optical system, noise created by mode-dependent optical losses and variations in the distribution of radiant power...

A photonic crystal surface-emitting laser (PCSEL) refers to a type of laser diode that emits light from its surface rather...

Transmission accompanied by diffusion or scatter to the extent that there is no regular or direct transmission.

A closely spaced series of well-known chemicals having a refractive index lying between 1.33 for water and 1.95 for a...

The utilization of the light produced when electrical energy is directly converted into light within devices used for visual...

Second-harmonic generation (SHG) is a nonlinear optical process that occurs when two photons with the same frequency combine...

A Laurent polarimeter is an instrument used in optics for measuring the rotation of plane-polarized light caused by...

Lasers based on neodymium-doped yttrium or gadolinium vanadate crystals. These include yttrium vanadate (Nd:YVO4),...

A resampling and interpolation method that uses only the value of the nearest neighbor pixel, while not considering values...

A lens made from transparent plastic material. Lenses over 31/2 in. in diameter are usually machined, ground and polished....

A type of asynchronous shutter device that is used particularly in CCD sensor applications to capture an image of a...

A photodetector mounted in the same package as a laser diode that is positioned to monitor the output from the rear facet of...

An instrument that is used to chart x-ray diffraction patterns, such as an x-ray spectrometer having photographic or other...

A gas lamp used in the early 1900s as a physical standard for measurement of luminous intensity. The Hefner unit was...

The transport of molecules in a cell which requires the use of a cell's internal energy. The energy used in the cell may be...

An instrument used to measure the light from a scene to be photographed and to indicate the camera lens and shutter settings...

A variation of the atomic force microscope that operates by scanning a tiny ferromagnetic probe (or a magnetized tip) over a...

An instrument similar to the spectroheliograph, but having a scanning method that is performed by a pair of rapidly...

Die bonding is a critical process in semiconductor manufacturing and microelectronics assembly, where a semiconductor die or...

A device used to count objects that pass a given point by allowing each object to obstruct a beam of light falling on a...

The process whereby pitch is broken and the lenses or blanks are removed from the block.

The optical Fourier transform is a mathematical operation applied to optical signals that involves transforming a spatial...

In polarized light, the plane of vibration that a polarizer will transmit.

A microscope that uses a reflecting objective; often used with ultraviolet or infrared radiation.

A moving group of fluid-suspended biological species directed through separate channels by which the population is isolated....

In optics, a motion controller refers to a device or system that precisely controls the movement of optical components, such...

An optical system used to collect infrared energy from a scene using scanning optics with a point or line detector, as...

A crystalline semiconductor alloy used as the light confinement layer in both single- and double-heterostructure diode...

An instrument used to test the hardness of various materials. It measures the pressure on a standard point that is necessary...

In an astigmatic grating, the image of the entrance slit located at the primary focus.

A cathode-ray tube that increases the brightness or size of an image or forms a visible image from invisible radiation. The...

A fiber optic end plate constructed by drawing a bundle of parallel fibers embedded in glass and cutting it into thin...

Photographic recording that uses infrared radiation as the light source to form an image of a microscopic object and a...

A meniscus that is often fitted before a camera lens to permit focusing on near objects.

LiFi, short for light fidelity, is a wireless communication technology that utilizes visible light or infrared light to...

Brillouin scattering is a phenomenon in physics where an incident electromagnetic wave (usually light) interacts with...

An instrument designed to place nongraphic information, usually generated by a computer, onto photographic film. The...

A device containing two opposed quartz wedges of equal angle, one wedge being movable along its length by a micrometer...

A substance capable of converting solar radiation into thermal energy.

Time-correlated single photon counting (TCSPC) is a technique used in photon counting applications, particularly in the...

A transmission electron microscope (TEM) is a powerful microscopy technique that uses a beam of electrons to create...

Light present in the environment around a detecting or interpreting device, especially a machine vision system, and...

A term used in data processing to describe a cathode-ray tube that displays graphic or character data.

A plastic disc coated with ferric oxide or other films on which data can be stored by selectively magnetizing areas of the...

A nonlinear crystal used to modulate a polarized beam of light by means of the Pockels effect. A Pockels cell is used as a...

A transparent crystalline substance that is anisotropic relative to the velocity of light.

An analytical technique used to determine, identify and localize impending malfunctions. It is based upon quantitative and...

Observed phenomenon of a small developed image with higher density than a larger image because of variation in photographic...

The use of photographic emulsions to detect and determine the amounts of ionizing radiation, such as x-rays and gamma rays,...

A telescope with a concave paraboloidal objective mirror and a small plane (diagonal) mirror that reflects rays from the...

In an optical waveguide, a ray for which geometric optics would predict total internal reflection at the core boundary, but...

1. Generally, an emulsion mask having a clean annular region in an otherwise opaque region. It is designed to eliminate...

Surface-enhanced Raman spectroscopy (SERS) is an analytical technique that combines the principles of Raman spectroscopy...

With respect to a crystal, the characteristic of possessing two ends symmetrical with each other.

A type of pyroelectric detector with favorable qualities of linearity, sensitivity and spectral responsivity used in FTIR...

An imaginary plane dividing a body into two parts so that each part is the precise mirror image of the other in the plane of...

Also known as ocular. The lens system used between the final real image in a visual optical system and eye. It acts as an...

Essentially, a hologram of a hologram, in which the first-generation hologram is masked with a narrow slit. During image...

A type of stereoscopic photography in which the distance between the two view points is greater than the average...

An image-forming system that uses mirrors rather than lenses. Such objectives are frequently used for astronomical...

Often referred to as the geometric center of a given image or image plane, the centroid of an image is a fixed point located...

Developed for use in military reconnaissance systems, it consists of a polygonal mirror, drive motor, interface between...

An apparatus, designed for use with a camera, that is used to rapidly open the path from lens to film, to maintain the...

An otoscope is a medical device used by healthcare professionals, particularly ear, nose, and throat (ENT) specialists,...

The unit angle, within an arc of a circle, equal to the radius of the circle (180/p°, numerically).

Fiber in which both core and cladding are made of plastic.

Relative to the Cotton-Mouton effect, the magnetic birefringence constant that, when multiplied by pathlength and the square...

Breakdown of a gas produced by the attenuation of an intense pulse of focused laser light.

A metabolite is any small molecule that is a product of metabolism, the chemical processes that occur within living...

A GRIN (gradient index) lens is a type of optical lens that utilizes a gradient in refractive index across its volume rather...

Pertaining to the manner in which light is reflected, as by a mirror or speculum.

A two-stage illuminating system for a microscope in which the source is imaged in the aperture of the substage condenser by...

Luminous flux emitted per unit area of a source, expressed as lumens per area.

Commonly known as CR39, this thermosetting plastic is used in the casting of eyeglass lenses because of its toughness and...

First stated by Abbe, condition states that the ratio of input and output angles, from object point to image point, for two...

An instrument for measuring the brightness (luminance) of a scene. It may be a spot meter, covering an area of a degree or...

Also cellulose acetate film. The emulsion layer applied to the substrate of a photographic surface. The emulsion layer is...

Spectral domain optical coherence tomography is an imaging technique used in medical diagnostics, particularly in...

Stimulating light used for the production of energy through photosynthesis, solar cell or other light senstitive device.

Photobleaching is a phenomenon in which the fluorescence of a fluorophore (a fluorescent molecule or dye) is permanently...

Multiple scattering method used in biological analysis in which approximations yield simple, explicit solutions, at least...

A fluorescent screen refers to a phosphorescent or fluorescent-coated surface that emits visible light when exposed to other...

A microscope designed with two eyepieces (oculars), permitting the use of both eyes when viewing through the instrument.

A method of producing x-ray exposures as short as 0.03 µs; the primary application is in ballistic radiography.

A photomultiplier tube (PMT) is a highly sensitive vacuum tube that detects and amplifies low levels of light. It is widely...

A device used to evaluate the luminance of a surface by determining the number of photons emitted from a sample surface area.

A volumetric electrical charge resulting from a flow of charged particles across a gap.

An electron tube whose electrical characteristics will not be affected by gaseous ionization because of its high degree of...

A transparent lead-lanthanum zirconate titanate ceramic with optical qualities that can be controlled by applying voltages...

Time-lapse optical coherence tomography (OCT) refers to a medical imaging technique that captures a series of sequential OCT...

A protective jacket added to an optical fiber to facilitate use in harsh environments. Armor usually consists of steel or...

A mirror that supplies equal reflectance for both the S-polarization and the P-polarization of a laser for a defined angle...

Totally coherent radiation is produced by a purely monochromatic point source. In the real world the energy will have a...

A plane mirror mounted on a polar axis that lies parallel to the plane of the mirror. When the mirror is rotated once in 48...

A microdisplay is a miniature electronic display technology that is designed to project visual information onto a small...

Graphene is a two-dimensional allotrope of carbon consisting of a single layer of carbon atoms arranged in a hexagonal...

Refers to a variety of methods and tools used to determine the surface contour and performance of optical components and...

A thermoplastic or optically transmitting hard plastic produced by applying polymerization initiator and heat to a monomer.

A source made to glow by electrons that are produced either electrically or by isotopes of various elements.

Two plane mirrors that are not wholly located in the same plane. When light from a point source or slit reflects from the...

Linear optics refers to the study and manipulation of light in a linear and deterministic manner, where the response of...

Process for growth of solar cells that results in rectangular shapes consisting of many interconnected cells in a series or...

An experimental research technique by which absorbed or unabsorbed radiation is analyzed in order to characterize and...

A compound lens combination whose astigmatic difference is zero for one or more off-axis zones in the image plane. In such a...

A form of binary notation that includes a third code representing a stop between bits.

Also known as Fresnel reflection. That portion of the incident radiation that is reflected from the surface of a refractive...

A technique for confining atoms, molecules or small particles within one or more laser beams. This can be accomplished...

The frequency band from 300 to 3000 MHz. The corresponding wavelengths are from 10 to 100 cm.

In optics, a shape often given to the leading edge of a projectile. In any side view it appears as a pointed arc, while any...

An eyepiece used in a polariscope or polarizing microscope to give a comparison view of the same object under illumination...

The distribution of electromagnetic fields in a given area. The units are volts per meter, watts per meter squared and...

The action of a biological system responding to a single or multiple coherent particles of light produced from a laser...

A relatively hard crystal, highly resistant to excessive energy radiation, that is frequently used for optical windows,...

A departure from ideal paraxial imaging behavior. The distortion of an optical field wavefront as it is propagated through...

A technique used in astronomy that requires a radio telescope to be directed at a point in the sky west of the object under...

An aerial photograph produced when the optical axis of the camera is perpendicular to the surface below.

The specular reflection of individual parts of a surface.

The region of the cathode-ray tube phosphor screen restricted by the tube and instrument specification.

Optical fiber is a thin, flexible, transparent strand or filament made of glass or plastic used for transmitting light...

A plot showing how the response (ability to detect a signal) varies with wavelength. D(l).

Data gathered by a facsimile system and converted into graphic, readable form; generally used in meteorology. Also known as...

A factor, F, indicating the increase in shot noise in an avalanche photodiode as compared with the ideal multiplier, which...

Parametric measurement for elliptical fiber and cable expressed as a ratio of the two-directional flow of power through the...

In a fiber optic cable, the longitudinal length required for the transmission media, wrapped around a central member, to...

A time-to-amplitude converter (TAC) is an electronic circuit that converts a time interval between two events into an...

A large table with an accurately designed plane surface used to test other surfaces, or to provide a true surface for...

The term for an image captured by a detector and from which a dark frame, bias frame and/or flat-field frame can be...

A photon sieve is an optical device used in the field of optics and imaging. It's designed to focus and shape light,...

The temperature above which a ferromagnetic material becomes only paramagnetic.

Differential interference contrast (DIC) microscopy, also known as Nomarski interference contrast microscopy, is an optical...

Nonlinear optics is a branch of optics that studies the optical phenomena that occur when intense light interacts with a...

An artificial star used to aid in adaptive optics imaging of the sky. The guide star is provided from a telescope system on...

A sensing or image-forming detector that serves to convert infrared rays into visible signals for communication purposes....

The line or lines emitted by an element when its radiation particles travel from one energy level to another.

A radioactive element that is placed or injected into a system to obtain an autoradiogram of the system. It is used in a...

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the...

In considering a field of electromagnetic energy emanating from a source, the wavefront is a surface connecting all field...

The mean square difference in a spatial parameter at points spaced a given distance.

A type of radial gradient lens that can focus light even though its surfaces are flat.

A surface heat-treating process that produces a highly stressed surface. In case-hardening of glass, a plate of glass is...

A type of motor that acts as the control element in a servomechanism. It is powered by an amplifier circuit and drives the...

The emission of a photon by the return of an excited carrier from the conduction band to the valence band of a semiconductor...

The determination of axially symmetric and asymmetric refractive-index distributions by use of interferometry carried out on...

The locus of the points in the field of binocular vision that are observed singly. The images of these points correspond to...

An ophthalmic instrument used to measure the magnitude and direction of the maximum and minimum powers of a spectacle lens,...

Also known as an optical diode, an optical isolator is a device that utilizes the Faraday effect to suppress or redirect...

State typically studied in liquid crystals in which the dielectric coefficient parallel to the director is less than the...

A multidimensional array of values that is commonly used in programming to describe a time series of image data. Each...

Laser marking is a process in which a laser beam is used to mark or engrave a surface by altering its properties or...

Photogrammetry is a technique used to obtain accurate three-dimensional measurements of objects and environments through the...

The use of photoetching techniques to produce small tools, parts and dies from sheet metal.

The pulse-to-pulse fluctuations in power distribution among modes of a Fabry-Perot laser, which can result in...

A semiconductor material used in photodetectors, sensitive in the infrared up to 5 µm.

Optical fiber that transmits a greater percentage of input light than does high-loss step-index fiber. Low-loss fiber...

In sensitometric testing, a series of areas progressing by equal density steps (usually the increments between steps are...

Left- and right-hand circularly polarized beams that are produced at different velocities by passing plane-polarized light...

A man-made satellite that orbits 35,680 km from the Earth at a rate of one orbit per 24-hour period, thereby retaining its...

The scattering of charged particles, moving through matter, by the electrostatic force exerted by other charged particles.

An aspheric mirror is an optical mirror surface that deviates from the shape of a perfect sphere, having a non-spherical...

A two-phase system consisting of dispersed liquid or solid particles in a gas; examples include dust, smoke and clouds.

In optics, the double refraction that is produced when stress is applied to a transparent material. Plastics, which are...

A glass that is heated, then chilled (usually by an air blast) to set up internal stresses so that the surfaces are under...

An area in which airborne particulates can be monitored and controlled so that given size particles do not exceed a...

A physical variable that is proportionally similar to another variable over a specified range. An analog recording contains...

Automated optical inspection (AOI) is a technology used in manufacturing processes, particularly in electronics, to...

A frame taken to identify electronic noise in a CCD imaging device. A dark frame is recorded without exposing the CCD to any...

A semiconductor material that is used as an infrared detector for light up to 5 µm in wavelength.

A porous ceramic substance that is ground to a given optical form and on which a polished plate of glass is sagged by heat...

A lens system made up of two sets of similar lenses, each of which compensates for many of the aberrations produced by the...

Fiber optic cable bearing many fibers independently sheathed and capable of carrying unrelated signals. They often surround...

A crystalline semiconductor material that transmits in the infrared.

An instrument used to record the emittance or reflectance of an object by scanning with discrete spectral resolution over a...

A relationship between two variables so that when plotted on a graph they yield a straight line.

Proportions of standard primaries (tristimulus values) required for a color match; ratios of each tristimulus value of a...

An acid used to etch the surfaces of particular materials. For glass, hydrofluoric acid is used either as a liquid or a...

A type of flat panel display made up of a layer of gas between two glass plates. The glass is coated with parallel...

The end of an optical fiber farthest from the source of illumination.

An image whose left side appears to be the right side, and vice versa.

The law stating that the illuminance (or irradiance) from a point source varies as the inverse square of the distance...

A technique based on the principles of laser trapping and used to manipulate the position of small particles by gradually...

1. In a plane Cartesian coordinate system, the vertical axis orthogonal to the X-axis. 2. In a quartz crystal structure, the...

The method by which photographic film is scanned by an electron beam. One technique uses the uniform light of a television...

Any arrangement of a bundle of optical fibers that alters the shape of the image. For example, by systematic regulation of...

The first-order spectrum formed by a diffraction grating.

A mirror coated to reflect cold (white) light while transmitting hot (infrared) energy.

An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the...

A projector designed to give each of the observer's eyes its own disparate image.

The ray that passes through the center of the aperture stop in an optical system. It often is called the principal ray of an...

Also known as zonal axis. The axis positioned through the center of a crystal that is parallel to a zone edge.

A detector sensitive only to signals close to or at a particular frequency that is the same as the frequency of a control...

The site behind the lens system in a camera where photographic media are positioned for exposure.

In the fabrication of an optical fiber, a layer that can be used to create a boundary against OH-ion diffusion into the core.

A reflecting prism that is rhomboidal in shape. It has two parallel transmitting faces, and two parallel reflecting faces;...

A vapor-phase oxidation process for fabricating graded-index optical fibers. It differs from outside vapor phase deposition...

Nd:YAG laser refers to a solid-state laser that utilizes neodymium-doped yttrium aluminum garnet (Nd:Y3Al5O12) as the gain...

Rolling shutter artifacts are distortions or visual anomalies that can occur in images or videos captured by cameras with...

Also called shining. Grinding and polishing one surface of a blank to permit a more thorough examination for quality.

Monolithic self-scanning linear image sensor array for multichannel spectroscopy with a spectral range of from 200 to 1000...

A telescope that corrects dispersion and spherical aberration through the use of one or more lenses, usually smaller than...

A homogeneous optical medium or coating that transmits only in particular regions of the spectrum. It is used to change or...

Laser sintering is an additive manufacturing (AM) or 3D printing technology that involves using a laser to selectively fuse...

An instrument that uses a blackened silver-disc reflector with a shutter to create temperature fluctuations that are...

A lens aberration, resulting from different magnifications in the various lens zones, that occurs in that part of the image...

Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in...

A handheld navigational instrument used to measure the elevation angle of celestial bodies such as the sun. An image of the...

Integrated photonics is a field of study and technology that involves the integration of optical components, such as lasers,...

A lightproof box used for storing photosensitive materials.

The point at which decreasing current supplied to a laser results in the extinguishing of the laser discharge.

A method for remote measurement of the temperature of moving surfaces in harsh environments by using a laser to stimulate...

A fundamental law of quantum theory which states that the discrete quanta of energy transfers associated with...

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing...

A fiber-coupled LED (light-emitting diode) refers to an LED device that is optically coupled to an optical fiber for the...

Family of deterministic models of plant canopy reflectance that provides deterministic formulation for each necessary...

A current-source thermal detector used to detect and study the pulses obtained from particular lasers.

An accelerator at the Argonne National Laboratory, providing powerful x-ray beams for materials research applications.

A doubly refracting mineral used to produce polarizing prisms. It is uniaxial negative and in the trigonal division of the...

An image intensifier tube in which the photocathode and the output of the microchannel plate are proximity-focused on the...

A process by which a plastic cell is molded around a glass lens or lenses to create a mount, eliminating the metal barrel...

Also known as gas focusing. The introduction of an inert gas into a cathode-ray tube for the concentration of the electron...

The process of transferring collected energy from solar radiation into a heat-absorbing medium (e.g., an insulated tank of...

The curved boundary between two optical media of different refractive indices, which causes convergence.

1. A term used to describe the clouded appearance of an incompletely polished surface that scatters light. 2. The...

Used for high-resolution surface study with subnanometer resolution. XRIM uses interfacial phase contrast with application...

A lens whose focal length is roughly equal to the diagonal of the negative format of the camera on which it is mounted.

For an electromagnetic field mode varying sinusoidally with time at a given frequency, the logarithmic rate of change, with...

With respect to a crystal, one of the paths or axes that will exhibit a piezoelectric charge when subject to tension or...

Germanium crystal refers to a crystalline form of the element germanium (Ge), which is a metalloid and semiconductor...

A 30-60-90° spectrograph prism that is coated on the surface opposite the 60° angle with a reflecting film.

An electron tube that stores and visually displays information by means of a cathode-ray-beam-scanning and charge-storage...

An instrument used for viewing in low levels of illumination by means of infrared radiation. A high-aperture lens forms an...

Chemical vapor deposition (CVD) equipment refers to a class of specialized apparatus used in the process of chemical vapor...

The color process that is used to form positive color cine films by dye transfer or imbibition, based on the use of separate...

A closed-loop system that compensates for thermal blooming by optimizing only one parameter: the amplitude of the phase...

Separation of incident laser pulses by several seconds so holographic plates can be changed and sandwiched between the...

Proprietary name for a low-light-level TV pickup tube.

An optical system with different focal lengths or magnification levels in perpendicular planes to the optical axis.

That element of a spectrum line in scattered radiation having a frequency equal to that of the corresponding incident...

Fluorescence lifetime imaging (FLIM) is an advanced imaging technique that provides information about the lifetime of...

The polymerase chain reaction (PCR) is a widely used molecular biology technique used to amplify a specific segment of DNA...

A Ti:sapphire laser is a type of solid-state laser that utilizes a titanium-doped sapphire crystal as the gain medium. The...

The electrical arc formed between metal rods that emits the spectrum of the metal itself. Commonly used in the chemical...

The sensitivity of a photographic emulsion when exposed to light, provided that the film is developed through a standard...

That surface of a lens located nearest to the eye.

The term reflective is an adjective that describes the ability of a surface or material to reflect light or other forms of...

Anisotropy refers to the property of exhibiting different values or characteristics when measured in different directions....

A semiconductor is a type of material that has electrical conductivity between that of a conductor and an insulator. In...

Power modulation refers to the intentional variation of power levels in a signal, often in the context of electronic...

The absorption index represents the imaginary component of the complex index of refraction, and not the real component. The...

A plasma accelerator is a type of particle accelerator that uses electric fields and magnetic fields to accelerate charged...

Plastic optical fiber (POF) is a type of optical fiber made from transparent plastic, typically polymethylmethacrylate...

A process used in pyrometry and photothermometry to create a photographic record of a surface's temperature gradients....

A photodetector composed of a photoconductive material that, when exposed to radiation, conducts without the aid of added...

An electronic tube instrument in which the anode current varies with the intensity of light incident on the cathode.

The parallel resistance and capacitance appearing between the active guard ring junctions in a silicon photodiode.

A photodiode that has been designed so that the bar of semiconductor material has a PN junction perpendicular to its length...

Older fiber optic cable that may not be suitable for state-of-the-art applications and that is difficult for suppliers to...

A system that determines whether an image is in or out of focus by means of a source of illumination at the conjugate focal...

Technique for measuring the volume bulk of materials as they move along a conveyor with an accuracy of better than 1...

Microscopy is a scientific technique that involves the use of microscopes to observe and study objects that are too small to...

An enzyme-linked immunosorbent assay (ELISA) is a laboratory technique used to detect and measure the presence of specific...

A quantitative measurement of the coherence of a light source; equal to the visibility (V) of the fringes of a two-beam...

The reflection that occurs within a substance because the angle of incidence of light striking the boundary surface is in...

A system of Japanese origin that utilizes Fresnel lenses and a fiber optic network to transmit sunlight to otherwise...

Intravital microscopy is an imaging technique used to visualize biological processes within living organisms, typically in...

The study and the interpretation of the infrared emittances of celestial bodies and phenomena.

A concave mirror that has the form of a paraboloid of revolution. The paraboloidal mirror may have only a portion of a...

An optical filter is a device that selectively transmits or blocks specific wavelengths, or colors, of light. Optical...

A very high bandwidth communication line often used in fiber optics.

Raman spectroscopy is a technique used in analytical chemistry and physics to study vibrational, rotational, and other...

An image consisting of an array of pixels that can have more than two values (black and white). Typically, up to 16 levels...

An arc lamp whose carbon electrodes are enclosed in a transparent chamber, resulting in an arc that is steadier, lasts...

The process whereby optical elements are removed from a block.

A crystal often used for windows and refracting components in the ultraviolet, visible and infrared. Characteristically,...

Directed energy refers to a type of energy that is emitted and transferred in a controlled direction. The term is often...

Light measurement by comparison of the luminances of unlike chromaticities.

A solar simulator is a device used to replicate the spectrum and intensity of sunlight in a controlled environment for...

An alexandrite laser is a solid-state laser that utilizes a synthetic crystal made from the rare earth element alexandrite...

An arc discharge tube having a grid that is used to start the discharge through an atmosphere of inert gas or vapor at low...

A group of adjacent pixels in an image representing the same value, as all black in a binary image.

The least space between two parallel lines that can be discriminated as a gap to the human eye. It is measured in terms of...

A frame taken with a CCD camera of a surface that is evenly illuminated by diffuse light. This frame shows irregularities in...

In optics, "mode beating" refers to an interference phenomenon that can occur in laser systems with multiple longitudinal...

Also referred to as primary color, this is the classic chromatic aberration of a single element caused by the variation of...

Gain-switching is a technique used in lasers to generate short pulses of light by modulating the gain of the laser medium....

The difference in angular bearing of an object as seen by the two eyes, due to the separation of the visual optical axes.

An event-based image sensor, also known as a dynamic vision sensor (DVS), is a type of digital imaging device designed to...

Image distortion that occurs when the axes of the original image are not perpendicular in the resulting image, making the...

Instrument that uses absorption spectroscopy to detect gases in planetary atmospheres. Dispersed incoming radiation is...

The photographic recording of images produced by the electrons from an electron microscope. The electron beam carries the...

Radiation having waves that are out of phase in space and/or time.

The process in which the electron beam of a cathode-ray tube varies in intensity in accordance with the magnitude of the...

A reflection grating is an optical component that consists of a series of closely spaced, parallel reflecting surfaces or...

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a...

The transfer of energy lost by radiation to the body, relative to the loss of energy per unit of path traveled.

The apparent luminance of the image as seen through an optical system. This brightness of the image is determined by the...

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual...

The time domain is a concept used in signal processing and analysis to describe signals in terms of their behavior over...

A spectrophotometer that makes use of filters to isolate narrow bands of the spectrum.

A source that attempts to create the characteristics of an ideal blackbody. It consists of a cavity, generally spherical,...

An input device for a computer that detects and reads the data, in the form of punched holes in cards, by light that is...

The alignment process that makes the optical axes of two related systems parallel to each other. Also, making the optical...

Cemented prisms of differing refractive indices which refract incident light and, due to differing refractive indices, will...

Literally, neodymium:yttrium-aluminum-garnet. A cylindrical rod of yttrium-aluminum-garnet doped with neodymium that is the...

Also known as a turned-down edge. A rapid change of curvature near the edge in a lens or prism surface.

A fast, wide-angle lens used in television and photographic cameras, with excellent overall correction, but subject to...

A form of mirage where objects near or just below the horizon appear in enlarged or distorted form because of atmospheric...

A technique for creating optimal performance in a system by producing a specific beam irradiance distribution, usually...

The angular width of a radiation beam. With respect to a conical beam of light, it is the vertex angle of the cone. The...

High-precision motorized positioning device, often linked to computer control equipment.

Three-photon microscopy is an advanced imaging technique that belongs to the family of multi-photon microscopy methods. It...

One of the types of change in the energy levels of molecules or atoms in a laser that can result in lasing action. Because...

In gradient index optics, a gradient profile in which the refractive index varies along the direction of light propagation,...

A pulse having extremely short duration, about 10-13 to 10-10 s, that is produced by mode locking of wide-bandwidth lasers,...

The longest wavelengths of the ultraviolet region, nominally 300 to 400 nm.

In electrical equipment, power variations that are temporary (as opposed to the permanent, cumulative effects of drift).

In a birefringent material, the index of refraction varies with the direction of vibration of a lightwave. That direction...

A refracting telescope that yields an erect image by the use of a positive lens for its objective and a negative lens for...

The apparent luminosity or glow that immediately envelops the cathode in a gas-discharge tube operating at low pressures....

Also known as TEA laser. A coherent optical source with a wide wavelength range in the infrared, visible and ultraviolet...

The optical process, following grinding, that puts a highly finished, smooth and apparently amorphous surface on a lens or a...

A method of coding image data by storing in memory only differences in brightness of each pixel from that of its nearest...

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of...

An instrument that measures several optical parameters, such as optical power and wavelength, with a single measurement...

A means of adjusting the sharpness of an image automatically, with a sensor for estimating distance or contrast and a drive...

Alphanumerical description of color according to Munsell hue, value and chroma.

Neuromorphic refers to the design and development of computing systems or devices that are inspired by the structure and...

A solid-state laser consisting of active atoms or ions of a transition metal, rare-earth metal or actinide, imbedded in a...

Hypothetical observer having standard color vision as described by standard color-matching properties.

A laser skin-resurfacing method that creates microscopic thermal wounds referred to as microscopic treatment zones (MTZs),...

A camera with a very high aperture lens or mirror system for photographing x-ray fluorescent screen images, mainly to save...

A waveguide having a characteristic that is altered continuously with the distance traveled, relative to the axis of its...

Optical aberration such that image magnification varies with ray distance from the optical axis in a radial distortion.

A zone plate in which the zones are alternately transparent and opaque to specific radiation, and coarse enough so that no...

A small bulb containing a conducting gas, an arc being formed between a metal ring and a tiny zirconium electrode near the...

A solar cell that is lightweight and flexible because of its construction by vacuum deposition of a semiconductor material...

In the most general sense, the resistance of a solid surface to damage.

The calculated normal distance from a photon source at which harmful interaction with the incident light will occur....

The term half bandwidth (HBW) generally refers to the width of a spectral band or frequency range at half of its maximum...

Specified curved optic intended for maximum collection of light, including off-axis rays, before leaving the exit aperture.

An atomic clock is a highly precise timekeeping device that uses the vibrations or oscillations of atoms as a reference for...

A lens having each of its outer faces curved inward.

Polarization refers to the orientation of oscillations in a transverse wave, such as light waves, radio waves, or other...

An edging stone having a relatively coarse abrasive.

An accurate metal prism or plane parallel plate that is cemented to an optical element and remains with it during a series...

A device that utilizes avalanche multiplication of photocurrent by means of hole-electrons created by absorbed photons. When...

Pertaining to radiation or particle emission, whereby the emission is produced with minimal energy spread.

Ultraviolet reflectance refers to the ability of a material or surface to reflect UV light. Ultraviolet light is...

Medical diagnostic (x-ray) imaging using laser printers to produce high-resolution digital hard copy instead of film exposed...

An instrument capable of precise measurements of the Earth's gravity. This permits the detection of small changes in local...

Quantum-enhanced metrology refers to the use of quantum mechanics principles and techniques to enhance the precision and...

An electron-beam tube designed so that the beam can be carried through a portion of the wall of an evacuated enclosure.

The process by which an atomic system changes from one energy level to another by either the emission or absorption of...

Consisting of, containing, pertaining to or yielding carbon.

Light consisting of a single wavelength or a very narrow band of wavelengths.

Formula that describes the thermal equilibrium of gas electrons and ions as a direct function of variations in temperature.

The conductivity increase exhibited by some nonmetallic materials, resulting from the free carriers generated when photon...

A close-up lens, semicircular in shape, that is mounted in front of a conventional lens focused at infinity. The result is...

Measurement estimated from the position of the image's centroid.

A cloud chamber designed to maintain the gas within it at a high pressure as a means of reducing the range of the...

A disc contained within an electronic cell counter for regulating light transmission.

A type of interferometer noted for producing narrow multiple-beam interference fringes. As a result, when compared with the...

Two oppositely charged particles.

A technique developed by British Telecom in which the viscous drag of air is used to install optical fibers in narrow...

A film of material that exhibits varying conductivity based upon its absorption of varying amounts of photon radiation.

A handheld, light-sensitive device that is used with a display console to directly change, measure or erase the visual...

Commonly performed in spectroscopy, the optical null process is a method for radiation detection whereby physical detectors...

The smallest linear diameter to which a laser or other beam of radiant energy is capable of being focused, depending on the...

The phenomenon that can render an optical resonator the equivalent of a semiconductor flip-flop. A bistable device will...

An instrument that serves to produce an enlarged electron image on a fluorescent screen by focusing an infrared image of a...

A type of additive color photography using a lenticular structure impressed on a film base and a camera lens with a filter...

A zone plate produced by a computer and having a binary structure that can be etched into a chromium or quartz layer. It...

An organizational method used in optical design computer programs. The technique produces one number (merit function) to...

Wavy transparent line in a sheet of glass appearing as though a thread of glass had been incorporated into the sheet.

A term used to describe a very coarse grinding process.

Unified notation for specification of reflectance in terms of both incident- and reflected-beam geometry; i.e., the ratio of...

A glass block that produces stationary fringes in the region crossed by incident light beams.

The scanning of photographs or transparencies of images, either by a vidicon camera or flying spot scanner, for the...

A type of recording material, usually a photodielectric polymer, offering in situ development mechanisms because of its...

A measure of image quality produced by an optical system. May be specified in terms of cycles per millimeter, referencing a...

A wireless stereo imaging device used in conjunction with a monitor to produce a virtual interactive environment. Liquid...

A mappable surface feature arranged in straight or curved lines that is distinguished from surrounding surfaces and is...

An optical compensator similar to the Babinet compensator, but which produces a phase-change consistent throughout its...

A crystal, glass, or quartz slicing and cutting machine is a specialized piece of equipment used in the manufacturing...

A phonon is a quantum of vibrational energy associated with the periodic motion of atoms or molecules in a crystalline...

Optical coherence tomography (OCT) is a non-invasive imaging technique used in medical and scientific fields to capture...

The compression and intensification of a laser pulse of a specific width into a smaller pulse width. A spherical cavity, in...

A two-lens arrangement intended to image light into a microscope slide sample. The primary aberrations present are red and...

A type of cooling system in which one fluid is used to carry heat off another without direct contact between the two.

An instrument capable of measuring the transmitted or reflected luminance from a very small area seen under a microscope....

A scanning probe microscope that analyzes the surface of a specimen by recording the intensity of light as it is focused...

In physics, nuclear fusion refers to the process in which two atomic nuclei come together to form a heavier nucleus,...

An artificial material, engineered to have a negative refractive index value, such that light or any other form of...

An optical gate typically refers to a device or system that controls the transmission of light, allowing it to pass through...

A photoconductive cell having cadmium sulfide as its photoconducting material for the production of a very high dark-light...

The substrate upon which a diffraction grating will be ruled. It must be dimensionally stable, and the surface must be...

Standard maintained by the International Commission on Radiological Units as a unit of radioactivity defined as the quantity...

A method of producing magnified images by x-rays. The specimen is placed close to a point source of x-rays; the...

Optimization method used in optical design computer programs that employs a variable-by-variable approach to construct new...

The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The...

An assembly of multiple prisms that disperses incident light into its spectral components without deviating light at the...

A cathode-ray tube that generates symbols for use in other displays. The tube operates by scanning specific characters on...

A unit of metric measure equivalent to 1 thousandth (or 10-3 ) of the standard unit of optical power which is the diopter (1...

A lens is a transparent optical device that focuses or diverges light, allowing it to pass through and form an image. Lenses...

The optical phenomenon in which white light dispersed by small particles in suspension appears blue when viewed through a...

A method of determining the abrasion resistance of very hard materials by passing a weighted wiper blade across them in a...

Solid-state laser geometry in which the standard rod is replaced by a slab of laser material. Often called...

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

Hydrophobic is a term used to describe substances or materials that repel or do not readily interact with water. The word...

Light produced when a metal is bombarded with high-velocity electrons causing small amounts of the metal to vaporize and...

In rudimentary form, this technology consists of diffusion of a PN junction through a mask of silica, over which a contact...

A gas laser equipped with Brewster windows and concave mirrors (having unlike reflective properties) at each end of the tube...

Area in which laser operation occurs and therefore safety requirements are met and regulations are implemented. Lasers...

An infrared imaging device composed of a detector array and readout electronics. It may include a cryogenic cooling system....

A galvanometric scanner, also known as a galvanometer scanner or galvo scanner, is a type of optical scanning device used to...

A type of fluorescence spectroscopy in which an excimer laser, a dye laser and a frequency-doubling device are used to...

An instrument that reads alphabetic, numerical and special characters by means of a photosensor that measures the varying...

An unbounded quantity, an indefinitely large number. Infinity is commonly expressed by the symbol ∞.

In a charge-coupled device, the percentage of each charge packet that is carried over to the next stage of the transport...

An EMCCD (electron-multiplying charge-coupled device) camera is a type of scientific camera specifically designed for...

In fiber optics, the condition in which each fiber of a bundle carries a separate channel.

An optical time-domain reflectometer (OTDR) is a specialized instrument used in optical fiber communications to characterize...

A type of wide-angle lens that has an angular field above 140° and that exhibits barrel distortion. The most commonly...

An arranged series of coils, magnets or electromagnets disposed in such a way that the resulting magnetic fields generate a...

That part of an infrared detector-Dewar assembly that limits the solid angle viewed by the sensor; it is maintained at a...

The particular orientation of the image, such as normal, canted, inverted or reverted.

Any noise or current fluctuation that prevents precise measurement of the signal current. Both dark current and signal...

A retroreflector that can focus a beam of light, with one planar reflective surface, one spherical and a third that is...

Describes devices that are not provided with a means of focusing.

Also referred to as fundus photography, ophthalmoscopy is the dioptrical study of the various interior components of the eye...

An electric discharge in a low-pressure gas having a low-current density and a space potential near the cathode that is much...

A device used to measure the pressure of gases and vapors, without regard to atmospheric pressure.

An imaging technique used in radiology that is based on the principles of nuclear magnetic resonance (NMR) to produce...

A device used to determine the location and attitude with respect to the Earth of orbiting spacecraft by detecting the...

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or...

An intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an...

A single number, defined by the computer program or the user that expresses the performance of an optical system. Also known...

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial...

A thin layer of a substance deposited on an insulating base in a vacuum by a microelectronic process. Thin films are most...

The study of the effects of light on the growth and development of various plants.

Method of disk rotation used for optical disk drives, in which the spindle motor decreases the speed of the disk's rotation...

A filter exhibiting transparency, absorption or reflectance characteristics specifically for spectral control of wavelengths...

A material consisting of very small colorless particles imbedded in a clear glass matrix. It is available in two forms:...

Consists of a pair of radio telescopes concentrated on a single celestial object. This technique creates a single radio...

Distortion caused by variations in the rate of change of phase shift with frequency over the signal's necessary bandwidth.

The electric arc that is a particular discharge between two electrodes in a gas or vapor which is characterized by high...

A type of spectroscopy used extensively in the analysis of biological samples. Because most biologically synthesized...

The study concerned with the stimulation of chemical activity by laser light as a result of the absorption of photons by a...

Silicon carbide (SiC) light-emitting diodes (LEDs) are semiconductor devices that emit light when an electric current is...

Holography is a technique used to capture and reconstruct three-dimensional images using the principles of interference and...

Two-photon excited fluorescence (TPEF) is a nonlinear optical method that allows imaging of biological cells and living...

A piezoelectric translator that moves up and down a spindle like a caterpillar. It clamps itself at one end, expands, clamps...

Continuous wave (CW) refers to a type of signal or transmission where the signal is constant and does not vary with time. In...

Epitaxial refers to the growth of a crystalline layer on a crystalline substrate in such a way that the orientation of the...

A hologram produced by a pair of radiation beams, each carrying information.

Temperature of the blackbody having chromaticity nearest to that of the test source on a specified chromaticity diagram.

A material in which the refractive index varies according to changes in the light to which it is exposed. Lithium niobate is...

A camera designed to form a continuous record of an expansive section of the horizon. The typical panoramic camera is...

The detection and measurement of nuclear and x-ray radiation.

End-fire coupling refers to a method of coupling energy into or out of a waveguide, transmission line, or antenna, where the...

An optical grating, in the context of optics and physics, refers to a device with a periodic structure of closely spaced,...

Also known as radiation thermometer. A pyrometer in which the radiant intensity from the source to be measured is used to...

The process or device by which more than one signal can be sent over a single channel by using different time intervals for...

A technique for measuring the energy spectrum of electrons emitted during the absorption of ultraviolet radiation. This...

A crystal of microscopic size having no definite plane faces and having a globular shape. At the time the crystal is formed,...

A device that holds a number of filters and allows the filter with the desired characteristics to be rotated into an optical...

Optical manufacturing tools and machinery encompass a wide range of equipment, instruments, and systems used in the...

An optical material used in place of crown glass to produce lenses with extraordinary correction of chromatic aberrations....

Also called calcite. A natural hexagonal crystal of calcium carbonate. It cleaves readily into rhomboids useful in the study...

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible...

The range of materials that, unlike glass, may be used in the infrared. Water-soluble salts, such as cesium iodide, and...

A variation of tomography, which is a means of visualizing any one of a large set of parallel planes in the patient. A...

Data communications network in a clearly defined geographical location, and extending no more than a few miles in length. It...

A diffraction pattern sampling unit composed of a 32-element monolithic silicon photodiode array and a readout unit. The...

A method of measuring microbending losses in optical fiber by sandwiching a length of fiber between two parallel plates,...

The use of variations in the power supplied to a laser to change the shape of the output pulse. The technique is used in...

A parallel plate of glass in such a position that the refracted and reflected rays of incident parallel light are mutually...

A sheet of thin brass, one edge of which has been accurately cut to a known and marked circular radius. It is used to check...

A lumen is a unit of measurement used to quantify the amount of luminous flux, which is the perceived power of light. In...

A multilayer coating that manifests both a low radiant reflectance and radiant absorption.

The method of disintegrating the substance of the cathode by bombarding it with ions and depositing it on another electrode...

The limited light-gathering area of an optical system. The area is normally restricted to an edge or outer surface of an...

E.I. duPont's trade name for a polyester film. The most practical beamsplitter for use beyond the 15-µm wavelength...

The unchanging nature of spectral reflectance as vegetational density increases to the point where additional increases in...

Capability requirement for optical switches for transmission lines to process arbitrarily polarized light because of the...

Fluorescence microscopy is a specialized optical imaging technique used in biology, chemistry, and materials science to...

In a gas, an electrical discharge that has no luminance.

1. A thin parallel plate of material that transmits in the infrared region. See infrared optical material. 2. A spectral...

Radiant power per unit source area per unit solid angle. Usually it is expressed in watts/m2/steradian.

The inductance of a closed circuit in which an electromotive force of one volt is produced when the electric current in the...

Gallium arsenide phosphide (GaAsP) is a semiconductor alloy composed of gallium (Ga), arsenic (As), and phosphorus (P). It...

In image processing, the memory that stores the values for the point processes. Input pixel values are those for the...

Liquid crystal on silicon (LCoS) is a display technology that combines liquid crystal materials with silicon-based...

A type of comparator with a telescope equipped with a cross wire mounted on a vertical sliding column. It is used to measure...

Description of a particle that cannot be superimposed on its mirror image.

Dispersion characterized by an increasing index of refraction in the medium as the frequency of the propagating light...

Laser powder bed fusion (LPBF) is a type of additive manufacturing (AM) or 3D printing technology that uses a high-power...

The formation of an interferogram by means of two holograms on the same recording medium, often used for determining small...

RGB stands for red, green, blue, which are the primary colors of light used in additive color mixing. The RGB color model is...

A large-scale, precise drawing of the contours of a perfect mechanical part, often with plus and minus tolerances drawn or...

A microscope that allows examination of a small crystal and conveniently provides linearly polarized object and reference...

The ability of a device to operate without electromagnetically interfering with the operation of nearby equipment and...

A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its...

A small object that behaves as a whole unit or entity in terms of it's transport and it's properties, as opposed to an...

The discernment of depth or apparent difference in distance that causes the object to stand out from its background because...

An infrared transmitting material used in the production of fluoride glasses for optical fibers.

In a laser diode, lateral motion of the beam center at the facet when the drive current is changed.

A visual defect that produces a disparity in the sizes of the images formed by the two eyes.

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot onboard. UAVs are remotely...

A type of geometrical distortion that brings about a trapezoidal display of a nominally rectangular picture. Usually...