A spectral signature, in the context of remote sensing and spectroscopy, refers to the unique pattern or characteristic spectral response of a material or object across different wavelengths of the electromagnetic spectrum. Each material interacts...

Any device in which the passage of electrons through a vacuum, gas or semiconductor is the principal means of conduction.

A nondestructive test, also referred to as LASAT, that uses a high-energy laser pulse that is targeted on an adhesively...

A source of radiation.

Attenuation refers to the gradual loss or reduction of intensity, force, or magnitude of a particular property as it...

A radiometric device or system having uniform responsivity relative to all of the radiation parameters, or relative to one...

A source of energy that produces needed excitation for population inversion in laser operation. The excitation source that...

A device for measuring absorption coefficients in which a confined, nonabsorbing gas fills the space inside the cell between...

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

The analysis, by x-rays, of the crystalline structure and other properties of metals and alloys.

An aspheric lens is a type of lens whose surface profiles deviate from the traditional spherical shape. Unlike spherical...

Having a longer axis that is relatively vertical.

The image of the aperture stop, usually the objective lens, that is produced by the eye lens. When the exit pupil of the...

A variation in propagation delay caused by differences in group velocity among modes of an optical fiber. Also called...

A compound crystal having two or more crystals or crystal sections that, when regularly positioned, are in reverse position...

A gradual change in the output of a circuit or instrument over time.

A system for fabricating optical fiber, consisting of a furnace that heats the materials, a polymer coating stage, a...

The generic term applied to all sources of visible radiation from burning matter to ionized vapors and lasers, regardless of...

In fiber optics, the limitation on performance imposed by the amplitude of a received signal rather than distortion.

A continuous-wave dye laser that uses a circulation pump and nozzle to provide an optically flat stream of dye across the...

An aberration occurring in a lens system when one or more of the centers of curvature of the optical surfaces do not...

Die bonding is a critical process in semiconductor manufacturing and microelectronics assembly, where a semiconductor die or...

An optical-quality polymer used in birefringent retarders.

A mechanism in a camera designed to position the film in the focal plane for exposure.

The distance between the object and the cornea, or the first surface of the objective in an optical device.

A rangefinder similar to a pair of binoculars with a long base, a dot or other wander mark provided in each eyepiece field,...

In morphological image processing, a series of dilations followed by the same number of erosions.

A type of erasable data storage device that uses a medium deposited on the disc in two layers, each dyed to absorb a...

The area of optics in which quantum theory is used to describe light in discrete units or "quanta" of energy known as...

A term for the ring-shaped stop in a phase contrast microscope. The phase annulus limits the amount of light that reaches...

Measurement of a translation stage's deviation from absolute straightness, that is, its angular motion in both the vertical...

The use of head-mounted displays and body-operated remote actuators to control distant machinery. Provides a virtual...

A semiconductor laser in which the naturally occurring broad linewidth has been narrowed by incorporating the laser diode...

A physical variable that is proportionally similar to another variable over a specified range. An analog recording contains...

The space between diffracting centers of an ultrasonic wave that is forming certain light diffraction spectra.

The final correction of a polished surface or of an angle to the specified precision.

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

A radiation detector with its active medium mounted within a lens that focuses the radiation signal. The improvement in...

Laboratory experiments that focus on demonstrating new capabilities of a certain technology or device, usually without...

See gimbal mount; kinematic mount; lens mount.

In the SI system, prefix meaning one hundredth, 10-2.

The ratio of emitted optical power of a source to the input electrical power.

A direct recording photometer that is designed to scan a photographic negative to determine its points of isodensity.

The near-point distance of the normal eye. The value of 10 in. or 25 cm is normal. This value is used in evaluating the...

Atmospheric aberration caused by the Earth's rotation; the degree varies from 0 at the poles to a maximum of 0.31 s of arc...

Image distortion that occurs when the axes of the original image are not perpendicular in the resulting image, making the...

A concept used for purposes of preliminary calculations and analysis. In theory it is a lens whose axial thickness is zero.

A photodetector, also known as a photosensor or photodiode, is a device that detects and converts light into an electrical...

A sensor generally used for infrared imaging. It consists of two chambers separated by a thin, blackened membrane. An...

The use of phase conjugation or other methods to increase the power density of a laser beam under adverse atmospheric...

Infrared radiation emitted from a source that is not heated sufficiently to give off visible radiation.

It is often necessary to estimate the value of what a pixel would be between neighboring pixels. This is accomplished by...

A flexible fiber cable with a small diameter that transports light from the excitation laser to the target. Used in Raman...

A part of the spectrochemical analysis of a sample that deals with the excitation of that sample by flame analysis.

One eyepiece of a set having equal distances from their mounting interface to their image plane, permitting freedom to...

A method of applying antireflection coatings to optics that avoids the elevated temperatures normally used. A cold coating...

A positive after-image that is maintained for a minute or more.

A double-plate device used to transmit polarized light and form interference fringes of the light, thus indicating its...

In fiber optic communications, a light source whose beam can be modulated and sent along an optical fiber, and the...

A phage, short for bacteriophage, is a type of virus that infects and replicates within bacteria. Phages are composed of...

An instrument used to determine the absolute or relative scatter levels of optical surfaces.

An instrument in which visible light beyond the critical angle from a metallurgical microscope is focused on a reference...

A salt of formic acid that can be used to enhance the photosensitivity of silver halide crystals.

Optofluidics is an interdisciplinary field that combines principles from optics and fluidics to create devices and systems...

A microscope that has an annular stop in the lower focal plane of the condenser, and a quarter-wave retarding and absorbing...

A method of designing lasers whereby the laser rod is cut into elliptical discs and cooled by running water over the disc...

The process whereby the shape of an optical surface is altered by polishing.

Machine vision, also known as computer vision or computer sight, refers to the technology that enables machines, typically...

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

A television system that is capable of producing an image whose colors approximate the colors of the original, by the use of...

The detection and measurement of spectral reflectance, spectral transmittance or relative spectral emittance, relative to...

Ultraviolet-C (UV-C) refers to a specific range of ultraviolet radiation with shorter wavelengths than those of visible...

In a cold-cathode tube, the luminance between the cathode dark space and the Faraday dark space. In a vacuum tube, the...

In an optical waveguide, a mode whose field decays monotonically for a finite distance in the transverse direction but which...

The partial differential equations for the spatial and time dependence of electric and magnetic fields inside a...

The locus of the points in the field of binocular vision that are observed singly. The images of these points correspond to...

A method of growing single crystals in which atoms and molecules from gaseous organic compounds interact and form a layer on...

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

A waveguide made up of a dielectric material, such as plastic or mica, in a cylindrical form, through which the waves travel.

A filter fluorometer that uses a photomultiplier tube to detect the fluorescence of a sample.

For each mode in an optical waveguide, the term used to describe the process by which an electromagnetic signal is distorted...

The vertical deflection of an image on a cathode-ray tube screen.

Two 30° prisms that are used to produce constant deviation when rotated by equal and opposite angles.

An imaginary line between the object, through the nodal point of the eye, and the fovea, or point of finest retinal acuity.

A laser rangefinder is a device that uses laser technology to measure the distance between the device and a target. It...

A spectroscope having a diffraction grating for the resolution of light of various wavelengths.

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

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

An image that is formed when rays emerging from an optical system are diverging from the optical axis. The virtual image is...

A general-purpose lens, also known as the Celor lens, used widely in photography and commercial processing; it has the form...

The fundamental wavelength standard of time or frequency. An atomic standard, it is properly expressed as 9,192,631,770...

Also known as the Wiener spectrum or the noise power spectrum, the optical power spectrum is a fundamental quantity in...

A fusion system conductor capable of carrying current in opposite directions in alternating time phases.

Used in halftone screens to change the fundamental sampled spatial frequency of the halftoned picture, as well as varying...

The minimum electrical current input needed to initiate lasing.

A laser that relies on chemical activity instead of electrical energy to produce the pumping action necessary to form pulses...

A camera equipped with a lens and a long length of perforated film, the latter being moved intermittently between exposures...

Carbonization is a process in which organic materials are heated in the absence of air, leading to the decomposition of the...

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

Optical fiber in which the attenuation exceeds the normally acceptable level for long-haul or data communications use.

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

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

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

The ratio of the number of bits received incorrectly to the total number of bits transmitted digitally in a system.

A nonabsorbing, multireflecting device, similar in design to the Fabry-Perot interferometer, that serves as a multilayer,...

A technique used to store wavefront information on thin polarization information-recordable materials by controlling the...

The ratio of the velocity of light in a vacuum to the velocity of light in a refractive material for a given wavelength.

A galvanometer having a small mirror that is mounted on a moving element and that reflects a light beam onto a scale.

An optical compensator similar to the Babinet compensator, but which produces a phase-change consistent throughout its...

The effect of a powerful gravitational field on light traveling through the field. This effect is detectable in astronomical...

A well plate, also known as a microplate or microtiter plate, is a flat plate with multiple small wells or depressions...

The use of a small ultrastable master oscillator (a diode-pumped Nd:YAG laser) to achieve single-frequency operation of a...

Ratiometry is a technique used in various scientific fields, particularly in analytical chemistry and biochemistry, to...

A solid-state device that acts as a high-speed power switch, and that is activated by incident radiation.

A method of determining the abrasion resistance of very hard materials by passing a weighted wiper blade across them in a...

An electron-beam tube in which the current to an output electrode is regulated by the transverse motion of the tube's...

Noise over a specified frequency range, in which the spectral density is proportional to the frequency instead of being...

A disc whose surface contains recorded digital data at high-packing densities arranged in concentric rings. The data,...

Optical switching refers to the process of controlling the routing or transmission of optical signals within a network using...

That radiation emitted by an atom or molecule that has the same frequency as that of an incident particle; e.g., a photon....

In analysis, the carbon layer that is evaporation-deposited on a specimen to protect and ready it for study by electron...

Time-lapse optical coherence tomography (OCT) refers to a medical imaging technique that captures a series of sequential OCT...

A test chart whose luminance changes uniformly in one direction according to a sinusoidal rule. These charts carry groups of...

A type of piezoelectric translator that uses two thin strips of piezoelectric material, one expanding while the other...

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

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

The angle that lies between the direction of an incident light beam and any resulting diffracted beam.

SI unit of luminous intensity. It is defined as one sixtieth the normal intensity of one square centimeter of a blackbody at...

Having human characteristics or behavior.

An endoscope is a medical device used for visualizing and examining the interior of hollow organs, body cavities, or...

The reduction in luminance of a light beam due to absorption and scattering as it passes through the atmosphere.

An instrument used to support optical parts to be cemented, or to be mounted in plaster.

The effect that the optical losses in a medium can grow when the medium is irradiated with light at certain wavelengths.

Radiography using the emission of x-rays to form an image of the structure penetrated by the radiation.

Vision by means of retinal cones; color vision. Relatively high levels of luminance are required for photopic vision.

Any filter in which the range of frequencies within a chosen radius suffers no attenuation and the range of frequencies...

A screen composed of a sheet of diffusing plastic material that reveals excellent image detail for close viewing. It is...

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

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

Light measurement by comparison of the luminances of unlike chromaticities.

A glow discharge tube placed on an insulating rod to detect the presence of high-frequency radiation in the vicinity of a...

Rayleigh scattering is a phenomenon that occurs when light waves interact with particles or molecules that are much smaller...

A photoelectrical relay that uses a phototube as its photoelectric device to open and close an electrical relay; used to...

An instrument used to measure the luminance (brightness) of a distant object. The object is viewed through a small...

A system designed to control the output quantity of a device by returning a portion of its output signal to its input. This...

A process that employs heat to remove polyimide plastic coatings from silica optical fibers and capillary tubing.

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

The application of photography, with the exception of radiography, to obtain pictures of parts or the whole of a patient to...

Laser annealing is a process that involves using a laser beam to heat and modify the microstructure of a material, typically...

A wave of radiant energy in which each point of the wave is repeatedly displaced at equal time intervals.

SI unit of quantity of light.

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

An organic light-emitting diode (OLED) is a type of light-emitting diode (LED) technology that utilizes organic compounds to...

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

Micro-optics refers to the design, fabrication, and application of optical components and systems at a microscale level....

A representation of the shape of a surface, including any roughness or other irregularities. The profile can be generated by...

A cathode that emits electrons, not with the influence of heat radiation, but by means of a high-voltage gradient at its...

A crystal-based device that combines and adjusts the intensities of multiple wavelengths of laser light in order to obtain...

A method of lasing in which free electrons in a laser-produced plasma collide with neonlike ions to excite electrons to...

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

Electromagnetic energy is transmitted in the form of a sinusoidal wave. The wavelength is the physical distance covered by...

Optic surface cleaning liquid that may be applied to glass, crystal, dielectric and metal surfaces; however, may not be...

In the context of optical materials, the term "impurity level" refers to the presence of foreign atoms or molecules within...

The degree to which a vision system is capable of sensing differences in light intensity between two regions.

1. A device generally used in a cathode-ray or camera tube to emit a stream of electrons moving at uniform velocity in a...

Gallium nitride-based light-emitting diodes (GaN-based LEDs) are semiconductor devices that emit light when an electric...

A spectrometer that uses a grating to diffract light into specific wavelengths.

A standard lens interface initially made for 16mm movie cameras and now used primarily on closed-circuit television cameras....

The use of photographs to record astronomical objects and phenomena for purposes of physical observation and measurement of...

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

The modification of the spherical surfaces in an optical system to correct for spherical aberration.

A television system that uses a slow rate of horizontal scanning to increase its reproduction and transmittance accuracy of...

A color center, in the context of materials science and condensed matter physics, refers to a specific type of...

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

Temperature of the blackbody having a spectral power distribution approximately proportional to the test source at all...

A spectrograph used to detect radiation in the range of the ultraviolet in the electromagnetic spectrum. It is made up of...

A small region within a single crystal where the molecules form a perfect lattice.

A bench with instrumentation including a collimator, a microscope, positioners and a nodal slide used to rotate a lens about...

A camera that uses multiple exposures to record the trajectory of an ordnance from a ground-level position.

In polarization-preserving optical fibers, the element used to induce birefringence. The SAP is highly doped to provide a...

The region of distorted atom configuration formed between the displaced and normal areas in a crystal when part of the...

A technique in which a beam of x-rays is directed against a crystal, the atoms of which, because of their lattice...

A technique that uses the passage of an electrical current through a recording medium to produce a permanent image on that...

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

A technique for measuring the energy spectrum of electrons emitted during the absorption of ultraviolet radiation. This...

The detection and measurement of nuclear and x-ray radiation.

A plotted relation between Log E (logarithm to base 10 of exposure in metercandle seconds) and density (logarithm to base 10...

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

Radiography using the emission of gamma rays to form an image of the structure penetrated by the radiation.

Fiber optic cable that operates at the 1300-nm wavelength.

The transmittance of a point on a photographic negative equal to the log to the base 10 of the reciprocal of the...

The superimposition of a pilot object on each hologram. The fixed relative position of the scanning and pilot beam during...

1. The continuous thin strip marked by the scanning beam. Generally, during return of the scan, the line is blanked out. 2....

A pattern on an oscilloscope display that consists of a string of shapes that resemble eyes. Because the pattern becomes...

A diode-pumped solid-state laser (DPSSL) is a type of laser system that uses semiconductor diode lasers to pump energy into...

Inquiry made to gain access by a master station in a token ring network.

The description of the refractive index along a fiber diameter.

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

In a fiber optic transmission system, the conversion of received optical pulses directly to an electrical signal.

A lens is a transparent optical device that focuses or diverges light, allowing it to pass through and form an image. Lenses...

In optics, the Pockels effect refers to the phenomenon where the refractive index of a material changes in response to an...

The average intensity of a light source measured over all directions.

Extreme ultraviolet (EUV) refers to a specific range of electromagnetic radiation in the ultraviolet part of the spectrum....

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

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

A lens system that is capable of producing a 360° image, or one that is very close to that. In recording, the image may...

A type of photoelectric proximity mode sensing incorporating a lens system to focus the light from the emitter in a small,...

A device that measures the spatial distribution of energy perpendicular to the propagation path of a radiant beam. An energy...

The interaction between two oscillations of unlike frequencies that forms other oscillations, specifically those with a...

Broadening of a spectrum that results from the influence of a magnetic field.

Scanning characterized by the generation of a plane or right circular cone with a vertex angle of about 180° by the...

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

A photographic process using x-ray radiation or the g-rays of radioactive materials.

Deep ultraviolet (DUV or deep-UV) refers to a specific range of ultraviolet light with shorter wavelengths than those in the...

A casting consisting of an optical material molded into the desired geometry for grinding, polishing or, in the case of...

A spectrum that displays the distribution in mass or in mass-to-charge ratio of ionized atoms, molecules or molecular parts....

Adhering material used to glue optical components that transmit in the infrared. It is easily dissolved by acetone.

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

In image processing and machine vision, the process in which an initial measurement pattern or some subsequence of...

A plate made up of thousands of glass fibers arranged parallel to one another, i.e., in a coherent bundle, and fused...

The underexposure caused by the diffraction of light passing through small openings spaced closely together in masks used in...

Oscillation in rod and disc amplifiers that critically limits the achievable energy storage.

The maximum rate at which temporally disjunct optical signals can be produced or detected.

A method of synthesis for crystals such as KTP. The process involves the use of a high-temperature solution called flux to...

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

A type of fatigue found in optical fibers, caused by water or another corroding agent.

Hardware installed on fiber cable ends to provide cable attachment to a transmitter, receiver or other cable. Usually a...

Formula that describes the thermal equilibrium of gas electrons and ions as a direct function of variations in temperature.

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

A crystal diode whose rectifying activity is determined by the touching of the crystal to a finely pointed wire surrounded...

Theoretical calculation of the cross section for a nuclear reaction given in the vicinity of a single resonance level in the...

A contact tip made of artificial sapphire (AlO2) that allows surgeons to use laser power to cut and coagulate tissue...

The magnetic flux that, linking a circuit of one turn, produces in it an electromotive force of one volt as it is reduced to...

A pair of telescopes with prismatically erected images, mounted side by side with the eyepieces at the interocular distance...

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

Device that uses a coherent reference wave to record the interference patterns produced by incident ultrasonic waves on an...

The perception of depth due to binocular vision.

The process of perforating a silicon or ceramic substrate with a series of tiny holes along which it will break. Nd:YAG or...

A narrow channel created by cleaving a crystal made of alternating layers of gallium arsenide and aluminum gallium arsenide,...

A device used in broadcast CCD cameras to improve definition in heavily saturated colors by band-limiting the color...

A device used to compare the luminous intensities of two sources by locating a point between the two light sources where the...

Oscilloscope electronic circuit that produces an output pulse whose pulse width is determined by the time that the output...

A laser oscillator in which two mirrors are separated by an amplifying medium with an inverted population, making a...

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

Photography involving the recording of events that occur too fast to be perceived by the human eye or recorded by...

The phenomenon in which alkali metals are transparent to ultraviolet radiation.

The direct computation of the Fourier transform of the space variant system output of an optical processor with a single...

A technique for creating optimal performance in a system by producing a specific beam irradiance distribution, usually...

That distortion resulting from dispersion of the group velocity of a propagating mode. It is the only distortion occurring...

Lasers based on neodymium-doped yttrium or gadolinium vanadate crystals. These include yttrium vanadate (Nd:YVO4),...

A graph of the intersections of a fan of rays with the final image plane, plotted as a function of the positions of the rays...

Spectra can be conveniently recorded on photographic film or plates. The portions that are occupied by regions of the...

Examination of the processes whereby heat energy is converted into other forms of energy.

A channel for communication with the source in an otherwise unidirectional network, such as a channel that provides...

A device utilizing an electron beam for the observation and recording of submicroscopic samples with the aid of photographic...

The continuous group of waves that persists for a short time only.

The distance from the final optic within a system to the rear image point of the system. See focal length.

The scale for floating hydrometers used to measure the specific gravity of a polishing suspension. The depth of immersion is...

An interferometer constructed to be positioned on a telescope to measure the angular separation of the components of double...

Of evaporative coatings, a condition resulting when small chunks of material fly from the hot crucible onto the substrate...

A Babinet compensator that contains the controlled motion of one prism with respect to the other. This idea was introduced...

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

A container which secures multiple splice trays and protects the trays and their contents from damage.

Thermophotovoltaic (TPV) refers to a technology that converts heat energy into electricity using the principles of...

The production of a positron-electron pair by a photon having energy greater than one mega-electron-volt, whereby some of...

A measure of film speed sensitivity to light.

The use of a micromanipulator in combination with a microscope for the purposes of examining, dissecting, or the...

A receiver-transmitter device that automatically transmits a signal when the proper interrogating signal is received.

A complex filter that uses polarization and interference to transmit light that is nearly monochromatic.

Straight line travel. This denotes the fact that light travels in a straight line when traveling through a medium with a...

An equation that uses the wavelength of light passing through a medium, along with a set of coefficients, to calculate the...

The region of the electromagnetic spectrum from 280 to 320 nm.

The electrical power used to stimulate any light source. Power supplies may be step-up or step-down transformers; rectifiers...

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

A graph used in photography to portray the increase of a film's density as its time of exposure increases.

A measure of the dispersive properties of a glass. The relative dispersion is defined as: where C, D, and F refer to the...

The bending of x-rays by the regular layers of molecules in a crystal acting like a very small diffraction grating. The...

A crystal often used for windows and refracting components in the ultraviolet, visible and infrared. Characteristically,...

The maximum variation in thickness of a lens as measured around a diameter centered on the optical axis. The ETD divided by...

A branched fiber optic lightguide that performs both receiving and transmitting functions.

A method of producing large volumes of plastic optical components in which powdered or sheet plastic is pressed between...

A function that quantifies the performance degradation of coherent communications systems, imaging systems and all systems...

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

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

A television system designed to obtain pictures of objects or scenes beneath the surface of the water. Generally, a...

An optical fiber with a hollow core filled with a liquid material that has a higher refractive index than the solid...

The study of the reversible conversion of chemical energy into electrical energy. Electroplating is an electrochemical...

Also referred to as the width of the dark pulse. This is the time interval between the instant the particle approaches the...

The distance, on either side of the object plane focused on, through which satisfactory image definition can be obtained....

The maximum level of laser radiation that a person may be exposed to without adverse biological effects.

A high-speed motion camera, also known as a high-speed camera or slow-motion camera, is a specialized imaging device...

A lens with aberrations corrected to the point that residual wavefront errors are substantially less than one-quarter the...

A profile of an optical component, usually a fiber, in which the core is of uniform refractive index and the cladding or...

A device designed to detect frequency-modulated signals by forming a unidirectional pulse from each sine wave. The direct...

1. The angle between two vectors that represent two simple periodic quantities that vary sinusoidally and that have the same...

The illusory appearance of a light or dark band at a line of brightness contrast that enhances the edge between the two...

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

A reflecting optic whose reflectivity is a function of the radial distance from the optic axis; can be used to convert a...

The spontaneous emittance of electromagnetic radiation by the nucleus of certain radioactive elements during their quantum...

Characteristic of radiation detectors that produce energy that is similar to the energy of superconductive gaps when...

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

The control of free electron movement through the use of electrical or magnetic fields, and use of this electron movement in...

A 30-60-90° spectrograph prism that is coated on the surface opposite the 60° angle with a reflecting film.

A screen with a reflected or transmitted light beam that is confined to a much smaller bundle than was received by the...

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

The ratio between the luminescence of an object and the luminescence of the scattering medium through which it is being...

An endoscope used for the visual examination of the bladder.

Micro-optical coherence tomography (micro-OCT) is an imaging technique that is an adaptation of optical coherence tomography...

The mathematical expression of the probability of any given state of energy being occupied when a semiconductor is in...

An instrument consisting essentially of a photoelectric cell filtered to respond to a specified wavelength region, an...

The area of optics in which the propagation of light is described by geometrical lines (or rays) governed by Fermat's...

A type of refractometer designed to measure the refractive indices of liquids. A section of the instrument is immersed into...

When a block of glass (prism, window, filter, etc.) is placed into a converging light bundle, it increases the physical...

The deformation of a material at high levels of stress, often associated with elevated temperatures.

A standard source of high-charge-state ions for accelerators that has an external magnetic field oriented perpendicularly to...

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

A method of terminating optical fibers by forming a lens directly on the end of the fiber, eliminating the need for precise...

Calculation of the probability of an interaction between two types of particles, such as light absorption, excitation or...

The creation of a diode laser structure by liquid-phase epitaxy over a grooved substrate.

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

A device that holds a number of filters and allows the filter with the desired characteristics to be rotated into an optical...

The process whereby a rotating wheel carries grains of an abrasive, suspended in a vehicle, across the surface of the...

Two-photon polymerization (TPP) is a technique used in additive manufacturing, specifically in the field of 3D printing. It...

A photon sieve is an optical device used in the field of optics and imaging. It's designed to focus and shape light,...

The central portion of the retina that has the greatest sensitivity to form and color.

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

A prism or prism assembly that serves to displace the instrument's optical axis.

A satellite-borne remote sensing device capable of transmitting images at 10 and 20 m resolution from an altitude of 830 km,...

A mode of laser printing in which each pixel is printed four times, providing sharper lines and a continuous tone from...

The relative path difference (or phase shift) traveled between two rays that pass through different mediums from the same...

The use of light to initiate the lasing process. See optical pumping.

The product of the actual base or baseline of a rangefinder or heightfinder, and the power or magnification of the...

Subsurface linear arrangement of elements of rock that is not mappable; lineation is a one-dimensional characteristic.

A filtering method that restores a blurred image by setting its power spectrum equal to that of the original image.

The first-order spectrum formed by a diffraction grating.

Micro-LED (micro-light-emitting diode) refers to a technology that involves the use of very small light-emitting diodes to...

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

A digital camera is a device that captures and records still images or video in digital format. Unlike traditional film...

Extraction of three-dimensional measurements from a stereo pair of photographs.

A coherent fiber optic bundle made from fibers whose diameter changes gradually along its length. Used to magnify or reduce...

Two or more lenses arranged to act in conjunction with one another.

Light-absorbing material that is applied to the back support of any bright image under inspection to prevent the formation...

Noise generated within an optical communications system link that has both internal (dark current) and external (background...

A solar cell that is lightweight and flexible because of its construction by vacuum deposition of a semiconductor material...

An arranged series of coils, magnets or electromagnets disposed in such a way that the resulting magnetic fields generate a...

For a detector, the amount of time alotted for the observation of one location.

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

A noncontact sensor used in the remote measurement of position, speed or other variables of moving parts.

A diode with a semiconducting material, such as germanium or silicon, for one electrode, and a fine wire "whisker''...

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

In fiber optic communications systems, generally one that operates between 1000 and 1700 nm.

The study of flames by means of a laser emitting blue light and a spectrometer to measure the green fluorescence created by...

Chromatic aberration is an optical phenomenon that occurs when different wavelengths (colors) of light are refracted by a...

That point in the electromagnetic spectrum at which an optical system focuses the most chemically effective rays.

A periodic structure formed by intersecting or superimposed laser beams. These beams can trap atoms in low-potential...

A method of measuring complex sequential photosynthetic reactions by varying the pulse time and wavelength of light...

An electrical or optical device used to convert color coordinates.

A dispersion relation defined in order to value the reciprocal amount of dispersion. It is defined as the refractivity over...

The entire range of colors a specific color model can produce, represented as a three-dimensional solid.

The basic process of color photography whereby colors are subtracted from white light by means of filters, making all colors...

The method used to measure the index profile of an optical fiber by placing it in an interferometer and illuminating the...

An experimental research technique by which absorbed or unabsorbed radiation is analyzed in order to characterize and...

An exaggerated depth appearance in stereo photographs caused by the lenses in the camera being farther apart than the eyes...

The component of a microscope on which the sample or slide to be examined is placed. Depending on the design of the...

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

Unified notation for specification of reflectance in terms of both incident- and reflected-beam geometry; i.e., the ratio of...

In infrared imaging systems used for mass screening of printed circuit boards or other quality control applications, an...

A term denoting the magnitude and direction of the magnetic field associated with an electromagnetic wave when describing...

The coherent wave used to play back a recorded hologram. It is identical to the reference wave used in the generation of the...

The luminescence of a substance resulting from its exposure to ultrasonic waves.

In computerized industrial process control, the element that determines the choice and sequence of operations dependent on...

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

Light that is a mixture of wavelengths.

Often referred to as the geometric center of a given image or image plane, the centroid of an image is a fixed point located...

The Fourier series representation of a two-dimensional periodic field, assuming that the original image is periodic both...

Optical elements arranged with no spaces between, so that the light travels only through glass, not air.

The line that divides the two half-images in a coincidence rangefinder. The two halves of the images formed by the two...

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

1. In optics, one of the exterior faces of an optical element. 2. The process of grinding or generating the face of an...

The range of image distances that corresponds to the range of object distances covered by the depth of field.

An array of lines in the infrared region of the emission spectrum of atomic hydrogen. Their wave numbers are expressed by...

1. The branch of physics that deals with the use of electrical energy to create or manipulate light waves, generally by...

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

Linear optics refers to the study and manipulation of light in a linear and deterministic manner, where the response of...

In aerial photography, the geometric method of indicating the three-dimensional location of ground points from a pair of...

A gelatinous fluid that can be used as a porous thin-film coating for optical components, including laser beam collimators,...

The numerical aperture of an optical system used to couple (launch) power into an optical waveguide.

The ray that passes through the center of the aperture stop in an optical system. It often is called the principal ray of an...

1. A contour map of a photographic deposit consisting of lines and curves that join points of equal density. 2. The...

Observed electroluminescence of zinc sulfide phosphors when excited by an electric field. This effect is the basis for the...

The variation in attenuation among the propagating modes of an optical fiber.

A material, often a liquid or cement, whose refractive index is nearly equal to the fiber's core index, used to reduce...

A camera tube widely used in television broadcasting. It consists of three sections within a single vacuum envelope. 1. A...

Ratio between map or photo linear distance and the actual ground dimensions represented.

A frame taken to identify electronic noise in a CCD imaging device. A dark frame is recorded without exposing the CCD to any...

A spectrophotometer designed for use in the 200- to 380-nm range of the electromagnetic spectrum and equipped with a...

The observation and measurement of the flatness of a mirror surface by contacting an optical flat with the mirror. The...

The study of the generation of electromagnetic power by radiation from high-energy beams.

Inertial confinement fusion (ICF) is a method of achieving nuclear fusion, a process where two atomic nuclei combine to...

A wave that changes from one amplitude to the other in a short time compared with the wavelength.

A measuring instrument composed of a microscope and reticle, and mounted on a calibrated slide mechanism. May be used...

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

A test for spherical aberration, coma or astigmatism in which incident rays from a point source are isolated by small holes...

A telescope stand equipped with a polar axis that can be set parallel to the Earth's axis of rotation and a declination axis...

A signal-averaging technique that improves signal-to-noise ratio by comparing a sampled signal with a reference signal...

In a laser diode, lateral motion of the beam center at the facet when the drive current is changed.

A filter that maximizes signal-to-noise ratio so that a waveform of known shape can be separated from random noise.

A mode possessing components of both electrical and magnetic field vectors in the direction of propagation.

The line or lines emitted by an element when its radiation particles travel from one energy level to another.

The process of subjecting glass to temperature cycling to produce physico-chemical reactions that alter its properties....

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

The inductance of a closed circuit in which an electromotive force of one volt is produced when the electric current in the...

A type of liquid-crystal display in which each display element contains an active component, such as a thin-film transistor,...

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

Photographic recording that uses infrared radiation as the light source to form an image of a microscopic object and a...

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

High-precision motorized positioning device, often linked to computer control equipment.

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

Technology that uses data from an array of sensors, one of which is commonly lidar, to solve the problem of creating a map...

A grating with ridges of rectangular cross section, generally equal in width to the space between. This type of grating may...

An aperture, usually rectangular in shape, with a large length-to-width ratio, and a fixed or adjustable shape through which...

A lens aberration, resulting from different magnifications in the various lens zones, that occurs in that part of the image...

Plasma-enriched deposition or planar magnetic sputtering that offers increased deposition rates in optical thin-film...

Description of a material, such as a water-soluble salt, that will continue absorbing moisture from the surrounding...

1. The decrease of the absorption (or gain) coefficient of a medium near some transition frequency when the power of the...

The angle formed between a ray of light striking a surface and the normal to that surface at the point of incidence.

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

A term used to describe a nondirectionally diffusing surface that, when illuminated, appears equally bright from all angles....

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

The use of miniature scanners to project raster-scanned video images directly onto the surface of the human retina,...

A form of mirage where objects near or just below the horizon appear in enlarged or distorted form because of atmospheric...

A step-by-step method of reducing the amount of data in a digital video signal to transmit or store a high-quality image....

A beamsplitting mirror that reflects as a function of wavelength.

A method of studying the chemical and physical properties of atoms and molecules (typically living tissue and chemical...

In its natural or original position.

The face of a cathode-ray tube (CRT) that has a fiber optic sheet attached to its surface. The sheet's fibers are at right...

A pair of long, slender parallel apertures used in experiments on diffraction and interference.

Graphene is a two-dimensional allotrope of carbon consisting of a single layer of carbon atoms arranged in a hexagonal...

Light leakage at a total reflecting interface when another highly refractive medium is brought close to it.

Glass designed to absorb most infrared and ultraviolet radiation while transmitting most of the visible region.

A very hard, highly transparent coating based on forms of carbon, used to protect optical components from abrasion and...

The ratio of the size of the image of an object to that of the object. The ratio of the linear size of the image to that of...

An acronym for microwave amplification by stimulated emission of radiation. Predecessor to the laser, the maser or...

A method of spectral analysis using wavelengths between 100 and 300 nm that utilizes both emission and absorption techniques.

A large telescope mirror fabricated from several smaller sections.

With respect to a television system, a pulse transmitted at the end of each field to break off the cathode-ray beam as it...

Characteristic of an acousto-optic modulator, defined by the overlap integral of the incident light and sound field...

A chemical reaction involving the production of light. The reaction of ethylene with ozone is chemiluminescent.

A region far from an aperture or source where the diffraction pattern is essentially the same as that at infinity. Changes...

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

The gradual decrease over time in output signal with constant input light level.

An exciton is a quasiparticle that represents the bound state of an electron and a hole in a solid-state material, typically...

A television receiver that receives the signals generated by a television camera directly, or remotely through a radio...

See plane-polarized light; polarization.

Class of organic dyes that emit coherent radiation over a wide spectral range.

A method that embraces the classical approach to image restoration and attempts to minimize the mean square difference...

The auxiliary electrode in a photomultiplier that gives rise to secondary emission and amplification when bombarded by...

In an interferogram, an intense portion of the recording that corresponds in size to the amount of infrared radiation...

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

The reduction in longitudinal, lateral and secondary chromatic aberrations in a lens or lens system.

The thick edge of a refracting prism.

A high-resolution spectroscopic device commonly used in the early 20th century as a component of double-beam...

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

A spectrophotometer having a pair of identical collimators with two Glan polarizing prisms, one fixed in azimuth and the...

A characteristic of laser output, calculated by dividing the speed of light by the linewidth of the laser beam. The temporal...

Spectrum analysis concerned with the spectra formed by transitions in molecules.

In dry etching, a method of characterizing the composition of solid materials such as metal. Atoms in the OES technique are...

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

An instrument designed to measure the index of refraction of a gas by the interference patterns formed by two beams, one of...

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

The radiation-free transition that takes place within an ion, in which inner-shell vacancies in neutral atoms are filled by...

A type of adsorption in which the adsorbed layer is attached to the adsorbent surface by an attractive force between the...

An infrared detector mounted directly on the cold finger of the Dewar cooler rather than at the interface of Dewar and...

The reflection that occurs within a substance because the angle of incidence of light striking the boundary surface is in...

This term literally means "to lag behind.'' It is quite often used to describe the residual effect that remains after...

Attosecond-pump attosecond-probe spectroscopy (APAP) is an advanced technique in ultrafast spectroscopy that allows...

In an optical waveguide, a ray for which geometric optics would predict total internal reflection at the core boundary, but...

A detector-Dewar assembly typically refers to a combination of a detector and a Dewar flask used in scientific instruments,...

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

Angular tracking measurement estimated from the properly normalized image second-moment tensor.

The glossy appearance of an object viewed, because of the binocular combination of two very unlike colors.

A type of fiber optic connector consisting of two cone-shaped ferrules aligned by a mating sleeve.

The astigmatism in a lens system that results when light enters the system at an oblique angle.

The computer module whose circuitry interprets instructions and guides the actions of the peripherals. Also known as the...

The integral of the radiance over exposure time.

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

An imaging device analogous to a drum scanner, but operating at greater speeds; it uses a row of sensors to traverse an...

The formation of an image by a pinhole aperture that transmits radiation, such as gamma radiation.

An optical system that is designed to produce a high temperature in a specified area by the optical direction and...

A semispherical or conical lens created directly on the core of an optical fiber to focus light from a laser into the fiber...

Radiation in which the phase relationship between any two points in the radiation field has a constant difference, or is...

1. A lens formed to a desired curve and used to form a polisher. 2. A piece of glass included in a block to fill out the...

A technique used to create an achromatic phase shift based on the principle of geometric phase. The phase shift is...

A high-speed cine camera used to record, on a continuously moving film, very brief events such as a flash of light. The...

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

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 statistical analysis of facts obtained when the intensity of x-ray diffraction is calculated at different angles. In this...

A multilayer coating that manifests both a low radiant reflectance and radiant absorption.

A film or plate that is usually coated on both sides with a very fast emulsion that is sensitive to x-rays, and used to...

A condition in which an emergent ray is perpendicular to the normal of the emergent surface of a medium.

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

Denoting a finished circular edge. A decentered lens is adjusted on a centering chuck so that its image runs true, and the...

A device used to take turbidimetric or nephelometric measurements by considering the contrast between a constant brightness...

Continuous conversion of oscillatory energy into heat, relative to time or distance.

In a pumped laser system, the ratio of output energy to pump energy.

A kind of spectrograph in which some form of detector, other than a photographic film, is used to measure the distribution...

Heating that results from the dissipation of energy.

A set of three colored lights which, when mixed, give the sensation of white light. The set used in color television, for...

A precise telescope set on a pair of rotation axes, the horizontal and vertical axes equipped with two divided circles. One...

An optical medical instrument that uses an intense, precisely focused beam of light to stop weakened blood vessels from...

A rangefinder on a camera that is integrated with the focusing mechanism so that when an object's range is determined, the...

A projection screen having vertical ribs or flutes set into a plastic surface.

Defines the minimum operational standards for a self-sustaining fusion reactor as equivalence between energy released per...

1. The photosensitive membrane on the inside of the human eye. 2. A scanning mechanism in optical character generation.

A metal-semiconductor-metal (MSM) photodiode is a type of photodetector that consists of metal electrodes on a semiconductor...

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

Epitaxial equipment refers to a set of specialized tools and systems used in the process of epitaxy, which is the growth of...

A viewfinder whose optical system forms a direct image of a subject, as opposed to those systems that use reflectance in the...

Variations in signal detected on a bolometer that are caused by instabilities in the temperature of the sky.

Trade name referring to an instrument that determines surface distances by measuring the length of time it takes for a...

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

Device used to measure the numerical aperture of a microscope, composed of a 14-mm-thick glass block with numerical aperture...

A photomultiplier tube (PMT) is a highly sensitive vacuum tube that detects and amplifies low levels of light. It is widely...

Metal used in components of the crystalline semiconductor alloys indium gallium arsenide (InGaAs), indium gallium arsenide...

Excimer laser coronary angioplasty (ELCA) refers to a medical procedure used in the treatment of coronary artery disease....

Laser light show effects equipment including optics and mechanical devices that reflect, position or distort the laser beam,...

An optical system having two sets of components separated by an air space, while successive lenses in each set are cemented...

A dichroic mirror, also known as a dichroic beamsplitter or interference filter beamsplitter, is an optical device that...

Extended period exposure photographs of a laser light created with various patterns within full image (laser graffiti).

A wave that is guided by the interface between two different media or by a refractive index gradient in the medium. The...

An instrument designed to produce very hard x-rays by the acceleration of electrons in a varying magnetic field.

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

Conceptual formulas that characterize both the transmittance functions of lenses and propagation in the Fresnel zone.

1. In optics, the bending of light rays toward each other, as by a convex or positive lens. 2. Turning in the eyes to view a...

1. A lens situated at or near the plane of an internal image to project the aperture of a previous objective or erector upon...

An instrument used for viewing in low levels of illumination by means of infrared radiation. A high-aperture lens forms an...

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two...

A symmetrical, very wide-angle lens. Well-corrected for spherical aberration and color, the Topogon can cover fields up to...

A photoelectrically controlled, alphanumeric reading device that converts characters to audible or sorting signals which can...

Integrated photonics is a field of study and technology that involves the integration of optical components, such as lasers,...

A measure of the sensitivity of a detector; the reciprocal of noise equivalent power (NEP). See D*.

1. A bundle of light rays that may be parallel, converging or diverging. 2. A concentrated, unidirectional stream of...

A method of focusing an optical system by moving the front component (the lens closest to the subject) to change the...

A specially designed microscope for observing the etched surface of a polished metal specimen. The specimen is often laid...

Stimulating light used for the production of energy through photosynthesis, solar cell or other light senstitive device.

A type of camera that incorporates a tiny mirror that oscillates in accordance with incoming signals. An illuminated slit is...

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

A mechanical, electrical, thermal or optical detector designed to identify and measure ultrasonic radiation.

Technology that relies on a highly efficient photodetector that can detect incoming light signals at one frequency and...

As applied to a device or machine, the ratio of total power input to the usable power output of the device.

Measurement derived from calculation when incident flux of a negative is entirely diffuse and all radiation transmissions...

A motion-picture camera that can be advanced one frame at a time, either randomly or at set intervals. Used in animation and...

The force acting upon a charged particle as it moves in a magnetic field, proportional to the particle's charge and velocity.

Description of a particle that cannot be superimposed on its mirror image.

Dispersion that occurs when the medium's index of refraction decreases as the frequency of the propagating light increases....

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...

Also referred to as the V number in fiber optics; the normalized frequency is a dimensionless quantity, denoted by the...

A blur circle refers to the out-of-focus region in an image captured by an optical system. When an object in a scene is not...

The figure of merit of a resonator, defined as (2p) x (average energy stored in the resonator)/(energy dissipated per...

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

Two essential pieces of equipment used in connection with the microfilming process: a camera capable of producing, on film,...

A spectrograph that uses a diffraction grating as its dispersive element in place of a prism, and yields greater resolving...

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

1. In optics, the housing, usually cylindrical, that contains the lenses and iris diaphragm of a camera. 2. In fiber optics,...

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

A material consisting of very small colorless particles imbedded in a clear glass matrix. It is available in two forms:...

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

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

A hemispherical covering that is rotatable about a central axis. There is a slit opening along one side wide enough to allow...

A reticle carrying patterns of various forms that can be rotated in an optical beam to cause variations in the intensity of...

Photoconductive antenna (PCA) is a semiconductor element that generates or detects high-frequency electromagnetic signals....

The separate spectral lines formed by a diffraction grating that are characterized by one wavelength difference in path...

Powder used to produce a smooth optical surface through abrasive polishing. Compounds may produce a surface finish specified...

In a laser, the fraction of plasma volume used by a particular transverse mode of oscillation, a determinant of the gain...

A collector for photovoltaic power generation that consists of a thin plate that strongly absorbs sunlight striking its...

A MEMS fiber optic switch is a microelectromechanical system (MEMS) device designed to selectively route optical signals...

A spectrum that originates from molecules and that is composed of bands which, in turn, consist of many closely spaced...

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

A shift in the apparent position of an object when an optical element is added or removed.

The photographic recording of images produced by the electrons from an electron microscope. The electron beam carries the...

The combination of two or more signals for transmission along a single wire, path or carrier. In most optical communication...

Motion of a fiber into and out of the ferrule. This effect is often caused by changes in temperature.

A night-vision device that uses one or more infrared transducers to scan a scene in the 3- to 5-µm or 8- to...

A technique whereby two laser beams, one at an excitation wavelength and the second at a wavelength that produces Stokes...

1. Synonymous with radioactivity. The intensity of a radioactive source illustrated as the number of atoms disintegrating in...

A device that combines electronic and optical techniques to form a monitored infrared signal between 1 and 14 µm. It...

An instrument in which an image of the sun is scanned by the entrance slit of a monochromator, the exit slit simultaneously...

The principle stating that the displacement of spectrum lines is determined by the distance between, and relative velocity...

The length of time during which the receiver is irradiated.

The use of a material's emissivity to measure absorption. It is useful as an absorption loss measurement technique, since at...

A semiconductor device with a semiconductor junction in which infrared radiant flux is nonthermally produced when a current...

A filter that controls the spectral composition of transmitted energy partially by the effects of interference. Frequently,...

The small central portion of the human retina that is responsible for providing the clearest, and most distinct aspects of...

An optical element having two principal axes, slow and fast, that resolve an incident polarized beam into two mutually...

A two-electrode device with an anode and a cathode that passes current in only one direction. It may be designed as an...

A factor that, when multiplied by the average candlepower emitted by a light source in a specified angular zone, reveals the...

A two-lens arrangement intended to image light into a microscope slide sample. The primary aberrations present are red and...

Nonspecular reflection from a rough surface.

A solid block of glass-ceramic material with holes drilled the length of all four sides, and mirrors attached to the corners...

The device, usually made of glass or a similar material, that contains the resonant cavity and optics of a gas laser.

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

Alphanumerical description of color according to Munsell hue, value and chroma.

An optical barcode reader, commonly known as a barcode scanner, is a device that uses optical technology to capture and...

A property of optical fiber that results from thermal stresses during manufacturing and is defined as the amount of...

A vidicon that has a photoconductive surface that can be excited by infrared radiation.

A layer of material applied to a coated surface to protect it from physical or chemical action.

1. An instrument used to measure the opacity or density of dyes, pigments or dispersed particles that form an image in or on...

A Nernst glower, also known simply as a Nernst lamp or Nernst filament, is a type of incandescent lamp or radiant heater...

An optical instrument that uses a yellow light of varying intensity with red and blue lights of fixed intensity to test for...

Measure of the interference fringe pattern produced by the forward scattering of light by an optical fiber; the fringe...

The point on a cutting line that will become the geometrical center of the cut lens.

Photoresist is a light-sensitive material used in photolithography processes, particularly in the fabrication of...

A microscope that uses a reflecting objective; often used with ultraviolet or infrared radiation.

1. The anode or anticathode of an x-ray tube that emits x-rays when bombarded by electrons. 2. The screen in a television...

Chemical vapor deposition (CVD) equipment refers to a class of specialized apparatus used in the process of chemical vapor...

The measurement of the intensity of spectral lines by the examination of a very small area under a microscope and the...

The force exerted on a surface by radiation.

Also called proximity focus image intensifier. A compact image intensifier that utilizes a microchannel plate...

A light source that is capable of producing radiation with waves vibrating in phase. The laser is an example of a coherent...

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

In image processing, the assigning of certain portions (or pixels) of an image a constant value of either 0 (black) or 1...

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

The expression denoting the ratio of the equivalent focal length of a lens to the diameter of its entrance pupil.

A quantum of electromagnetic energy of a single mode; i.e., a single wavelength, direction and polarization. As a unit of...

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

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

Hypothetical observer having standard color vision as described by standard color-matching properties.

A graduated range of stimuli perceived as having equivalent differences of brightness.

The growth of particular grain fragments in a metal or alloy, at the expense of others, that occurs when the metal or alloy...

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

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

1. The value on either the leading or the trailing edge of a laser pulse at which the power is one-half of its maximum...

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

1. A defect inherent in a multiple-axis positioning system whereby an adjustment of one axis causes an undesired change in...

A unit of metric measure equivalent to 1 thousandth (or 10-3 ) of the standard unit of optical power which is the diopter (1...

The process of making an abrupt break in a spherical surface on a spectacle lens so that a new center of curvature is set...

A type of thermoset rubber used to jacket fiber optic cables, including those used in outdoor military installations.

An oil required by oil-immersion objectives that is applied between the exterior of the objective lens and a cover glass or...

The portion of a glow discharge tube that permits little or no light transmission.

The light ray leaving a reflecting surface, indicating the path of light after reflection.

A current-source thermal detector used to detect and study the pulses obtained from particular lasers.

A transition boundary between two regions having different properties in a P-type semiconducting material.

Low Earth orbit (LEO) refers to a region in space that is relatively close to Earth's surface, typically characterized by...

A camera used to reduce originals onto film for easy storage. There are two basic types: one in which the film is fixed...

A photonic cavity, also known as an optical cavity, is a structure that confines electromagnetic radiation within a certain...

A defect in the cleaved end face of an optical fiber, in the form of a sharp protrusion at the edge of the fiber.

Also referred to as differential interference contrast (DIC) microscopy; Nomarski microscopy is a unique form of microscopy...

The ratio between two given absorption coefficients.

The attraction of particles suspended in a solution to a cathode, as a result of an electric field.

A moving group of fluid-suspended biological species directed through separate channels by which the population is isolated....

The total scattering attributable to the intrinsic properties of the materials through which an optical wave is propagating.

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of...

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

In the field of optics and imaging, a mesoscope refers to an optical instrument that is designed to observe and capture...

An optical waveguide having a silica core and a plastic cladding.

A highly flame-retardant material used to jacket fiber optic cables, especially on shipboard applications.

In interferometry, the result of superimposing two wavefronts of identical shape, yielding a uniform intensity interference...

A conical or cylindrical package of light rays emanating from a common point on the object.

Surface analysis by means of photon induced electron emission. PEM methods provide high lateral resolution of the observed...

The process of forming a polisher by pressing it with an optical surface.

Used for high-resolution surface study with subnanometer resolution. XRIM uses interfacial phase contrast with application...

A device similar to the ordinary spectrophotometer but containing particular modifications to provide for the comparison of...

A neutral-colored gelatin wedge, cast between glass plates, that is used as an intensity scale in certain types of...

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

A filter, used in photography, that absorbs the ultraviolet and extreme blue violet radiation scattered by atmospheric haze.

An endoscopic surgical instrument that includes a channel for the introduction of supplementary instruments.

A hyperspectral imaging camera is a sophisticated imaging device capable of capturing and processing data across a wide...

A material used as a protective layer on an aluminized or silvered mirror. It is evaporated on the mirror as a thin layer,...

A spectrophotometer is a scientific instrument used to measure the intensity of light at various wavelengths in the...

The deposition of a metallic coating, usually nickel, on a component by chemical means rather than by electroplating; the...

A method of fabricating an optical waveguide by melting the core and clad glasses in two suitably joined concentric...

The movement of particulate material by flowing gas or liquid.

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

1. In a plane Cartesian coordinate system, the vertical axis orthogonal to the X-axis. 2. In a quartz crystal structure, the...

The propagation or hindrance of waves reaching each aperture of the interferometer because of atmospheric turbulence.

Energy loss encountered at connectors in optical fiber transmission systems. The major contributors are mutual core...

Collaborative Robot (Cobot): Unlike traditional autonomous robots, which usually work by themselves, a collaborative robot...

A projector used to project transparencies. A horizontal 8 x 10-in. stage for writing or laying down preformed...

A circular optical wedge (prism of small refracting angle) mounted to be rotated in the path of light rays to divert the...

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

In biology, particularly genetics and evolutionary biology, the phenotype refers to the observable characteristics or traits...

Electron released in photoelectric activity.

A microdisplay is a miniature electronic display technology that is designed to project visual information onto a small...

The color process that is used to form positive color cine films by dye transfer or imbibition, based on the use of separate...

An instrument devised by Nichols and Hull for use in the measurement of radiation pressure. The device has two small...

An interference filter in which a very thin metal foil with a periodic array of square holes (inductive mesh) or a thin...

That voltage required across a Pockels, Kerr or other electro-optic light modulator to retard one polarization electrical...

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

In optical fiber, sharp but microscopic curvatures that create local axial displacements of a few microns and spatial...

Remote sensing is a method of data collection and observation where information about objects, areas, or phenomena on...

The analysis of the atomic structure of a sample by means of a source radiation that is absorbed and emitted by the sample...

That plane in an optical system containing its optical axis and the chief ray. Also called the tangential plane.

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

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

A device consisting of two optical systems in which two signals are simultaneously transformed to produce their spectra, and...

Also known as an anticathode. An electrode or electrode section that is focused upon by an electron beam and that emits...

In gradient index optics, a gradient profile in which the refractive index varies along the direction of light propagation,...

The deviation from the ideal case where a circular variable filter is located at a given wavelength along a radial line (or...

A device that measures the wavelength of an electromagnetic wave.

Photochromic refers to a property exhibited by certain materials, typically organic compounds or dyes, which undergo...

A solid-state laser that is continuously tunable in the wavelength region from 700 to 1100 nm. It is suitable for both...

A tool of cast iron or another suitable medium used with a slurry of silicon carbide, aluminum oxide or emery for grinding...

A single wavelength of light that matches the color of a given sample when combined in suitable proportions with white light...

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

The underexposed collodion that is present on a glass negative as a positive when backed with material.

An optical matrix that does not require perfection in both states of the crosspoint, so that all the optical switches can be...

Relation between a material's transport rate and the material's concentration gradient and the diffusion coefficient.

The luminous flux emitted by a light source in all directions.

The use of high temperatures, between 2000 and 3000 °C, to excite emission lines from a sample in spectroscopic...

A telescope with an ellipsoidal secondary concave mirror that reflects rays from a parabolic primary mirror through an...

Spatial resolution refers to the level of detail or granularity in an image or a spatial dataset. It is a measure of the...

Photon flow created by imaging of light into a detector array; IPD is the electrical signal used by the image processor in a...

The interference pattern formed by light waves diffracted at the edges of an object as seen on a screen placed in their path.

A unit of luminance equal to 1/p candela per square meter.

A vision defect commonly referred to as nearsightedness. The defective condition results when the image of a distant object...

The ratio of Young's modulus to density of a material.

One or more spots placed in the field of view of an optical system to provide a means of reference.

Conductor element for use in integrated electro-optic systems that measures current flowing through it.

A lens system made up of two sets of similar lenses, each of which compensates for many of the aberrations produced by the...

This type of miniaturized system, referred to as CMOS qPCR, combines microfluidic technology with an ultralow-light CMOS...

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

The separation between the exit pupils of a binocular instrument. This usually is adjustable so that it can be set equal to...

See optical time-domain reflectometry (OTDR).

A special evacuated camera equipped with means for holding a specimen and bombarding it with a sharply focused beam of...

Any ray through an optical system that is not a meridional ray. The plane created by a refracted skew ray does not contain...

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

That property of a material indicating that it will react when exposed to light energy.

Optical elements, often created by micromachining, lithography or vacuum deposition, that rely on diffraction of the...

An image with variations in density due to the differential scattering ability of microscopic bubbles in a transparent layer.

A Darlington current amplifier consisting of two separate transistors, of which a phototransistor is the input device.

A vapor-phase oxidation process for fabricating graded-index optical fibers. It differs from outside vapor phase deposition...

The line of vision; the optical axis of a telescope or other observation system. The straight line connecting the object and...

The optical phenomenon that causes relative motion between two objects when the eyepoint is moved laterally. When parallax...

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

Equipment dependent on the effects of a vacuum. The principal applications in optics are in the coating of lenses and...

A specialized form of diffraction grating consisting of assembled glass plates of equal thickness that resemble a flight of...

Electron lens consisting of an homogeneous axial electric field.

A matrix-controlled display that has no information storage at the display surface.

The physical center of the lens; it is on the axis of the lens, halfway between the front and rear vertex. It is sometimes...

Descriptive of the radiant power of visible light modified by the eye response. It is the measure of the flow of visible...

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

The graphic recording of physical changes vs. time, in electrical quantities, using an oscilloscope.

A mount that uses a floating suspension and a motor-driven gyroscope to keep a motion picture or still camera at a set angle...

In printing, a translucent screen used with lenses to provide an even distribution of diffused light.

An instrument for measuring the radius of curvature of a spherical lens or mirror surface. It may consist of a ring resting...

Integral densities that are measured relative to arbitrarily selected red, green and blue filters.

The use of two lasers as a master-slave pair in order to control frequency and prevent chirp. When light from the master is...

A mechanism or device, especially a coating with a refractive index equal to or slightly greater than that of an optical...

A highly reflective mirror that is usually flat on one surface and curved on the other, and that has silver, gold or...

An image intensifier, also known as an image intensification tube or image intensification device, is a specialized...

A surface that envelops a bundle of rays or bundle of normals to the wave surface. It may be observed as a hollow, luminous...

One surface of a nonconducting plate that is coated with many minute particles of photoemissive material that are insulated...

A type of sheathing for fiber optic cable that incorporates a coil of metal; often used in harsh environments.

The area of optics that deals with the interaction of light with a given material. The optical properties of material are...

A thin film or coating that forms on various finished surfaces. On optical surfaces it usually denotes aging.

An automatic camera that can record reduced images of documents at a rate of up to 30,000 documents per hour by having the...

1. Lines of the same color. 2. A term used in photoelastic stress analysis to refer to the interference fringes produced in...

A hologram formed when the light of the illuminating beam is absorbed in correspondence with the recording exposure. In...

An electroluminescent semiconductor that emits low intensity radiation in the green or red regions. Used as an indicator...

The dark absorption lines observed in the spectrum of the photosphere of the sun. There are thousands of these lines, the...

Pertaining to the manner in which light is reflected, as by a mirror or speculum.

Stochastic optical reconstruction microscopy (STORM) is a superresolution microscopy technique that enables imaging of...

An instrument designed for laser technology that is used to extract single pulses from the laser and transmit a portion of...

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

Stress applied to an optical fiber at a constant rate.

A thin-film device containing miniature optical components connected via optical waveguides on a transparent dielectric...

The ability of an optical system to make an object appear larger. An optical element or optical system causing an object to...

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

The optical form of the crystal fluorspar, calcium fluoride, that is utilized for its low optical dispersion, its low...

The use of photographs taken from specially placed cameras, to develop, through computation, a spatial solution of the...

Automated optical inspection (AOI) is a technology used in manufacturing processes, particularly in electronics, to...

The properties exhibited by a semiconductor as the result of its modification by imperfections and impurities in the crystal.

The difference between any color and a reference color having equal luminance and a specified chromaticity.

A crystal having the axes of its grains aligned so that they have directional magnetic characteristics.

An instrument used to detect and measure radiant energy by the formation of a chemical reaction.

In a lens or other optical system, the image of the aperture stop as seen from object space.

The study of the optical properties of living tissue. Increased understanding of the behavior of light in this varied,...

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

Mathematical definition for the changes that occur between potential and kinetic energy. These formulas express wave motion.

A numerical representation of the rate at which a material will exhibit dimensional changes as a direct result of changes in...

The point at which decreasing current supplied to a laser results in the extinguishing of the laser discharge.

The sine of the vertex angle of the largest cone of meridional rays that can enter or leave an optical system or element,...

The group of adjacent pixels on which the convolution process is carried out.

A pulsed interferometer that permits the continuous quantitative mapping of the surface deformation of an adaptive optical...

A condition causing variation in output power that is eliminated by mode locking.

In optics, the double refraction that is produced when stress is applied to a transparent material. Plastics, which are...

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

Any object that emits radiation of a wavelength lying between about 0.75 to 1000 µm. A calibrated secondary source...

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

Average wavelength usually determined for light-transmitting devices by taking a weighted average for each wavelength of the...

A method of optical fiber coupling in which the fibers are ground down to expose their cores and placed together to allow...

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

The unusual and anisotropic diamagnetic quality observed in particular crystals such as those composed of bismuth.

A spectroscopic technique used to display the intensity of an optical pulse as functions of time and frequency...

A technique used to suppress extreme noise amplification during digital image reconstruction that relies on smoothing and...

Optical elements that have been coated with one or more layers of dielectric, or metallic material. These coatings serve to...

Exhibiting the characteristic of materials that are electrical insulators or in which an electric field can be sustained...

Light generated along the interface when light is incident in the neighborhood of the total internal reflection angle.

Ratio of the radiance of the specimen to that of a perfect reflecting or transmitting diffuser identically irradiated.

A CCD device in which a solid-state electron multiplying register has been added to the end of the normal serial register....

Refers to the voltage and current necessary for the operation of circuit devices.

The size of the field of view in the object space of an optical system as differentiated from that in the image space...

Also known as aplanatic lens. A lens corrected for spherical aberration and coma.

Relative to radiation wavelength, the law that states that the wavelength of luminescence stimulated by radiation always...

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

Intravital microscopy is an imaging technique used to visualize biological processes within living organisms, typically in...

Any substance or space through which electromagnetic radiation can travel.

Noise generated in the flow of current in the photomultiplier, produced by the intentional or controlled application of...

An SI prefix meaning one billionth (10-9). Nano can also be used to indicate the study of atoms, molecules and other...

A general term referring to the situation in which an image is not a true-to-scale reproduction of an object. The term also...

A microscope to which a beamsplitter and illuminated reticle have been added to measure the radius of curvature of a...

A family of lenses commonly used in scan systems for reading or printing documents. The lens must be designed such that the...

Observed phenomenon of a small developed image with higher density than a larger image because of variation in photographic...

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

A critical image parameter in applications where object position may change dynamically relative to the imager; this is a...

A fundamental law of wave scattering theory that connects the extinction cross section of a scatterer to the real part of...

A type of additive color photography using a lenticular structure impressed on a film base and a camera lens with a filter...

A type of copying camera in which the object is placed on a horizontal easel and photographed by a horizontal camera above...

A grating in which the wires or rods are set radially within a circular structure.

A device used to evaluate the quality of fiber optic splices made in the field by injecting light into the cladding of the...

The ejecting of ions from the surface of a material.

A crystal consisting of a substance that has the ability to become electrically polarized and has strong piezoelectric...

The method of disintegrating the substance of the cathode by bombarding it with ions and depositing it on another electrode...

A device that detects radiation by utilizing the influence of light in forming an electrical signal. It may be a phototube;...

A photoemissive detector sensitive to wavelengths up to 1 µm. It has one sharp maximum of sensitivity at 350 nm and a...

The study of the reflection or transmission properties of specimens as a function of wavelength after they have been excited...

Infrared radiation absorbed by crystals as a result of the excitation of lattice vibrations in which ions having opposite...

A form of high-power microscope objective where the space between the object and the first element is filled with an oil...

The quantity (C) of electricity transported in one second by a current of one ampere.

A film of material that exhibits varying conductivity based upon its absorption of varying amounts of photon radiation.

The generation, usually by a cathode-ray oscilloscope, of a two-dimensional image having a three-dimensional appearance.

Technique for measuring the volume bulk of materials as they move along a conveyor with an accuracy of better than 1...

Imaging materials that generally consist of a polyester base, a transparent electrically conductive layer and an organic...

In fiber optics, a device used to polish a biconic plug to a specified length and surface finish. Also called a polishing...

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

gas laser using ionized argon as the active medium and applying electronic excitation in order to produce the laser light

A type of eyepiece, or the modification of an eyepiece, in which a small hole, without a lens, functions as the eye lens;...

Amplification; the result of the excess of stimulated radiation over absorbed radiation.

Radiation from the invisible (usually ultraviolet) region of the spectrum.

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

The finite amount of electrical charge generated in response to incident radiation and transferred from one storage element...

The finishing of the edge of an optical element by grinding.

An adhesive used to affix optical elements to an approximately shaped body -- usually of cast iron.

A volumetric electrical charge resulting from a flow of charged particles across a gap.

With respect to a chromaticity diagram, this is the locus of points that represent the chromaticities of blackbodies...

Abbreviated PAI. An imaging modality with a hybrid technique based on the acoustic detection of optical absorption from...

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

A sensitometer having a continuously controlled monochromator to measure spectral sensitivity and contrast of photographic...

A measure of the total light passed by a shutter during an exposure, compared with the light that could be passed by an...

Characterizes an Earth-orbiting satellite whose orbit plane is near polar and positioned at an altitude that allows it to...

An instrument that uses a blackened silver-disc reflector with a shutter to create temperature fluctuations that are...

Quantum efficiency (QE) is a measure of the effectiveness with which a device or system, typically in the context of...

An optical fiber's absorption of electromagnetic waves due to hydroxyl ions remaining after contact with water.

The lowest anode voltage at which a gas tube can sustain a discharge.

A matrix-controlled display that has information storage at the display surface, and requires that an element be addressed...

Any noise or current fluctuation that prevents precise measurement of the signal current. Both dark current and signal...

A law that uses the square of the cosine between the plane of polarization of a beam of plane-polarized light and the plane...

An instrument designed to collect naturally formed extraterrestrial electromagnetic radiation within the radio frequency...

A ratio expressing the difference in power between the output fibers of a coupler or splitter.

The production and analysis of spectra with the use of a spectrograph.

The angle between the light input propagation vector and the optical axis of an optical fiber or fiber bundle.

A form of liquid crystal with an appearance of moving, threadlike structures, particularly visible when observed in thick...

An alternative term for incandescence.

Infrared (IR) refers to the region of the electromagnetic spectrum with wavelengths longer than those of visible light, but...

Pitch, wax, resin or other cement suitable for holding optical parts to a spindle during grinding and polishing processes.

A method of erasable optical data storage in which information is stored by visible light, then read by illumination with an...

The intensity regulation of a cathode-ray tube by alteration of the grid-cathode voltage.

As a wavefront of light passes by an opaque edge or through an opening, secondary weaker wavefronts are generated,...

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

Increase in the diameter of an initially collimated beam, as measured in milliradians (mrad) at specified points; i.e.,...

An infrared device used in satellites and rockets to determine a heat horizon for the Earth at altitudes (above 200 miles)...

In optical character recognition systems, the identification of a character facilitated by means of known factors governing...

Additive manufacturing (AM), also known as 3D printing, is a manufacturing process that involves creating three-dimensional...

Production of a repeated image of a transmitted beam through a diffractive optical element such as a holographic card or...

In computer graphics, intersection of a plane with a three-dimensional object to create a sectional view.

Fluorescence is a type of luminescence, which is the emission of light by a substance that has absorbed light or other...

A type of optical microscope that allows the specimen being viewed to be irradiated by ultraviolet, violet and occasionally...

The nondestructive analysis and recording of industrial components based on the absorption of relatively low-energy neutrons...

A mixture of phosphor with a trace of a radioactive element that emits faint light continually. It is used on watch dials...

The angular difference in the direction of an object as seen from two points of observation. The angle subtended at the...

The electrostatic field acting locally within a crystal as a result of the microscopic arrangement of atoms and ions in the...

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

Technique for the precision evaluation of coincidence of a laser beam's center with the edge of the object under study and...

Ink used for writing on glass, and also for blackening the edges of lenses to prevent reflection. In the latter case, the...

A display that allows the observation and measurement of the altitude and range of airborne objects.

Pockels cell or dynamic optical retarder in which the electrical field is applied in a direction parallel to that of light...

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

The effect, present in particular phosphors, that is defined as a transformation in the dielectric constant of a material...

The reversible change in the absorption spectrum of certain compounds upon irradiation with a given wavelength of light.

CID, or charge injection device, camera refers to a type of imaging device that utilizes a specific kind of solid-state...

One of a number of nuclides characterized by an identity between their mass numbers, but each having a different atomic...

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

Free-space optics (FSO), also known as optical wireless communication or optical wireless networking, refers to the...

One or more thin-film layers of optical material deposited on a mirror blank/substrate in order to enhance the way that...

A cathode-ray tube that increases the brightness or size of an image or forms a visible image from invisible radiation. The...

The greatest luminous reflectance possible for a specified chromaticity.

A plate of glass in which a face has been frosted by grinding or etching. It diffuses light by scattering in directions...

1. With respect to radiation, a device used to attenuate particular wavelengths or frequencies while passing others with...

A defect on or in an optical element that does not appreciably impair the function of the surface.

Neuromorphic refers to the design and development of computing systems or devices that are inspired by the structure and...

A device for measuring diffraction grating efficiency at any angle of incidence, consisting of a reflectometer wherein the...

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

The angle subtended by two points or lines that are just far enough apart to be distinguished as separate. The ability of an...

The emission and/or propagation of energy through space or through a medium in the form of either waves or corpuscular...

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot onboard. UAVs are remotely...

Aspect of vision permitting the observer to distinguish among stimuli by their hue, saturation, and brightness or lightness.

The circle that contains the slit, grating and primary astigmatic focus of a concave diffraction grating.

The angular change of an incident beam due to vibrational induced refractive index changes within a crystal.

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two...

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

1. A thin parallel plate of material that transmits in the infrared region. See infrared optical material. 2. A spectral...

A system designed with a laser as a light source and a means for producing sound waves extending beyond 100 MHz to deflect...

A diagram that shows actual component signals and the basic wiring configuration of a relay logic circuit.

A phenomenon, exploited for medical imaging, in which the nuclei of material placed in a strong magnetic field will absorb...

The emissivity of a body times the emissive power of a blackbody at the same temperature. For a blackbody, it is the total...

Also known as a gray body; a nonselective radiator is a thermal radiator that has a constant spectral emissivity with...

A rotating mirror coupled with a distant mirror and used in a system by Foucault to compute the velocity of light. Light...

The ability of an electrical current to destroy superconductivity by means of the magnetic field generated by the current....

The unwanted and unpredictable fluctuations that distort a received signal and hence tend to obscure the desired message....

The process of forming a lens to a given pattern, or of cutting a piece of glass along the line of scratch.

A lock-in amplifier is a specialized electronic instrument used to extract and measure small signals embedded in noise or...

The process by which the values of one digital image of an object or scene are removed from a second slightly different...

The production of holograms initially from either conventional photographs or incoherent optical equipment.

A chemical compound that exhibits a reversible change in its absorption spectrum upon irradiation with given wavelengths of...

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

The rotation of an instrument (or the line of sight of an optical system) in a horizontal plane; transverse.

The emission spectrum formed by the radiation from a sample that has been evaporated by a nonluminous flame.

The ratio of energy or intensity absorbed by the medium (numerator) to the total incident energy.

A type of ultrasensitive laser spectroscopy that can detect quantities as small as a single atom of some substances and that...

A tabulation of predicted positions that have been calculated for one or more celestial bodies or orbiting satellites.

Radiation consisting of more than a single wavelength in the visible region of the spectrum.

A plate containing a uniform pattern of transparent holes in an opaque background, the clear area being nearly equal to the...

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

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

The permanent uniting of two glass pieces by high-temperature heating.

The normal condition of vision where an object at infinity is in sharp focus with the eye lens in a neutral or relaxed state.

A wave of radiation that has undergone refraction.

The plane in which the axis of maximum radiation and the electric vector are contained.

In optics, a collapsible structure situated between the lens and film of a camera to allow variation of the distance between...

Laser-powered telephone device for analog communications that employs a vibrating plastic membrane as a transmitter to...

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

Structural color refers to coloration in materials that is not caused by pigments or dyes but is instead a result of the...

The unit generally used to express distances within the solar system, and sometimes to measure interstellar distances....

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

In computer graphics, the point on the display screen where the electron beam is located before the display instruction is...

In an interference pattern, that point where there is no difference between the optical paths of the interfacing wavefronts.

On a chromaticity diagram, the point that denotes the chromaticity sample.

The decrease of a component's efficiency, or a reduction in a material's light sensitivity, as the result of accumulated...

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

An instrument used to recognize and identify incident radiation by the ionizing or stimulating properties of the radiation.

Analysis of the reflection spectrum that allows the determination of the experimental dielectric function.

An optical filter so constructed that the density increases progressively from one end to the other, or angularly around a...

1. A method of photographing distant objects with a lens of long focal length. 2. The reproduction of photographs over a...

1. A piece of glass with plane parallel surfaces used to admit light into an optical system and to exclude dirt and...

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

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of...

Holographic quantity expressed as the ratio of the reconstructed first-order image to that of the incident reconstructing...

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

Triggering a laser at a predetermined time by pumping it to a level just below its threshold and then using an auxiliary...

A photometric instrument having two prisms clamped in optical contact to produce a photometric field with an acute dividing...

Calculated at a given point in a medium as the instantaneous pressure at that point in the presence of a sound wave, minus...

Developing a photographic image by means of an applied electric field. The methods used include electrolysis and...

Voltage that produces current flow in the direction of lesser resistance to the steady-state direct current, i.e., from the...

Any of the many devices used to detect the presence of radiation from a specific region of the electromagnetic spectrum.

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

A device, either visual or electronic, that emits signals to identify set positions for use in the navigation of aircraft...

Q-switched operation, or q-switching, is a technique used in lasers to produce short and intense pulses of light. The term...

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

See color perception test equipment; eye test apparatus.

A characterization of the throughput performance of data storage systems; the EDR is the total of data retrieved divided by...

A process of isolation of various atom vapor ions by means of tuning a laser source. For example, laser enrichment is...

1. A generic term for detector. 2. A complete optical/mechanical/electronic system that contains some form of radiation...

A form of a stereoscopic microscope having paired objectives, prisms and eyepieces, and invented by H. Greenough.

Refers to a variety of methods and tools used to determine the surface contour and performance of optical components and...

An ocular having two planoconvex lenses that are formed from similar glass and that are separated by a space equal to half...

An optical storage product that can be used for playback only.

Virtual histology refers to the use of digital technology and computational methods to simulate or recreate histological...

A photovoltaic device that consists of multiple p-n junctions to produce a greater efficiency when in use than that of...

The surface from which electrons are ejected by the incidence and absorption of photons.

A very high bandwidth communication line often used in fiber optics.

Fizeau fringes are interference fringes observed in an interferometer, specifically in a Fizeau interferometer. The Fizeau...

Quantum entanglement is a phenomenon in quantum mechanics where two or more particles become correlated to such an extent...

A unit of luminance that is equal to one candela/cm2. (sb).

A system that is complete and self-contained, needing no further additions to permit its operation.

Optical fiber with a large core, often a step-index fiber; "large'' is at times defined as greater than 85 µm.

An eyepiece consisting of two planoconvex lenses of the same focal length, with facing convex surfaces.

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

An instrument used to measure the duration of fluorescence emanating from a biological sample to monitor and evaluate its...

The decrease in power that occurs when an optical beam or signal is transmitted through a system.

An impurity-doped silicon detector array sensitive to long infrared wavelengths, installed in optical collecting systems...

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

An inspection device in which the profile of a mechanical part is projected onto a ground-glass screen at a precisely known...

A parabolic, elliptical, hyperbolic or circular section created when a solid cone is intersected by a plane.

A lens, one surface being a cartesian oval, that produces an aplanatic condition.

The instrument used to analyze a pulsed electromagnetic wave to determine its time, amplitude, duration and shape, and to...

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

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

To control, by magnifying or reducing, the size of a televised image, either electronically or optically.

In a remote sensing system, nadir refers to the point on the ground located vertically below the center of the system. In...

A mixed-signal oscilloscope (MSO) is a type of electronic test instrument that combines the capabilities of both a...

A light-harvesting protein found in the purple membrane of a micro-organism called Halobacterium halobium. The protein...

A theoretical analysis of radiation loss from planar optical waveguides due to scattering by surface irregularities/surface...

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

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

The unit of the dose of any radiation that produces the same biological effect as one roentgen of x-ray.

An instrument designed to place nongraphic information, usually generated by a computer, onto photographic film. The...

A convention that defines specific dimensions of an optical system, such as the image distance or radius of curvature of a...

In surface height measurement of optics with steep slopes, the use of two short visible wavelengths to synthesize a longer,...

An approach to optical character recognition based on matching the input character against a set of stored prototypes.

A system of beacons used in navigation.

Distortion of the high frequencies of a signal. In television, the term generally applies to frequencies above the 15.7 kHz...

The number of electrons that can share a principal quantum number by preventing identity between any two electrons' four...

Optical aberration such that image magnification varies with ray distance from the optical axis in a radial distortion.

A method used in surface quality testing for accurate positioning and rotation of metal spheres about an axis or fixed point...

The path of a given point on a wavefront. One of the radii of a wave of light that indicates the direction of light travel.

The probability that an atom in one state will move spontaneously to a lower state within a given unit of time.

Also known as amplification. 1. The increase in a signal that is transmitted from one point to another through an amplifier....

A type of lamp that emits a high quantity of ultraviolet radiation. This may be an arc lamp encased in a bulb of a glass...

A measure of the optical path length for light traveling from the sun or other celestial source through Earth's atmosphere...

The diffraction pattern of a source such as a light-emitting diode, injection laser diode or the output end of an optical...

Spectrophotometry in which radiation of two separate wavelengths, usually one in an absorption band and the other not, pass...

The branch of science that treats light as a wave phenomenon wherein light propagation is studied by wavefronts rather than...

The distance between two focal lines in an astigmatic image produced by a lens or mirror.

See charge-coupled device; charge-injection device.

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

Solar radiation intensity existing in free space at the mean solar distance of the Earth. Commonly expressed in g cal...

With respect to photography, the law stating that the optical density of an exposed emulsion with standard development is a...

Refers to transistors in which the working current flows through two types of semiconductor material: N- and P-type. In...

An absorbing coating medium between fibers, used in some fused fiber optic plates to absorb unwanted light. Such coatings...

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

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a...

Scientific complementary metal-oxide semiconductor (sCMOS) refers to a type of image sensor technology specifically designed...

A unit of energy equal to the amount of energy absorbed by one molecule of material undergoing a photochemical reaction, as...

An optical system of variable focal length, the focal plane remaining in a fixed position. This result is achieved by moving...

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

The fiber optic connector developed and manufactured by Amphenol Fiber Optic Products.

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

A photodetector in which an electrical charge is produced when incident photons change electrons within the detecting...

In photoelectric sensing, the portion of the transmitted beam that actually functions in the system; the diameter of the...

A simple electrostatic lens with a focus controlled by a single potential difference.

The area in a 2-D or 3-D microdisplay viewer within which the eye can move and still see the entire image.

The polymerase chain reaction (PCR) is a widely used molecular biology technique used to amplify a specific segment of DNA...

The diffraction of a particle by a standing lightwave.

The equation devised by Sir G.B. Airy for the analysis of light diffraction near a caustic surface: (d2f/dz2) - zf = 0 where...

A thermosetting material used in the jacket of fiber optic cables.

A highly accurate cathode-ray tube used to display information with the utmost efficient stability and resolution. The...

The optical phenomenon in which white light dispersed by small particles in suspension appears blue when viewed through a...

Bardeen-Cooper-Schrieffer theory of superconductivity, based on the notion that electrons with opposite momentum and spin...

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light...

In a CD-ROM disc, the reflective area between nonreflective pits representing a binary-language "off'' as opposed to...

A contraction of "excited dimer." The term refers to an excited species made by combination of two identical atoms...

A method for characterizing a fiber wherein an optical pulse is transmitted through the fiber, and the resulting light...

Light from a pulsed laser focused into nonsaturable absorbing fluid that generates a strongly backscattered light beam with...

The position and shape of the image of a point source, as predicted by geometric optics alone. The geometric image is to be...

The recording and mathematical analysis of all spectral intervals of the spectrometer simultaneously.

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

A machine vision technique of image correlation whereby the correlation kernel (template of the desired image) is...

A system of sensors and related instrumentation that allows a navigable object (usually a missile) to locate its destination...

A high-speed shutter, similar to a Kerr cell, that uses the birefringence produced in a liquid during the passage of an...

A sensitometer that utilizes an electronic flashtube or a photoflash lamp as both the light source and the shutter for...

That property of a substance that determines that there will be a decrease in conductivity when exposed to light radiation.

Two simple meniscus lenses arranged symmetrically on either side of the aperture stop, providing reduced coma, lateral color...

Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications...

A technique for confining atoms, molecules or small particles within one or more laser beams. This can be accomplished...

A laser having a rod that is a stacked array of discs immersed in a transparent flowing coolant fluid. In this way, the...

A microscope that has been modified to permit the quantitative analysis of dust samples.

The power that gives rise to the production of energy at the rate of 1 joule per second.

Brillouin scattering is a phenomenon in physics where an incident electromagnetic wave (usually light) interacts with...

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

A filter that transmits a single spectral line emitted by a line source.

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...

In multifocal spectacles, a term used to denote glass with a high refractive index that has been fused to the blank and...

Unlike the thermocouple or bolometer, the pyroelectric infrared detector is a current source with an output proportional to...

Process that occurs when a polymerized soft plastic rod with higher refractive index is placed in a bath of a lower...

A thermoplastic or thermosetting material used to hold an object fixed and keep it from deterioration. In microcircuitry,...

A thermocouple that is used in infrared spectroscopy to detect a sample's infrared emittance. See thermocouple.

In optical communication systems, operations in which the amplitude of the pulses, as opposed to their width, determines the...

A system that allows the transmission of more than one signal over a common path, by assigning each signal a different...

A near-infrared (NIR) spectrometer is an analytical instrument used to measure the absorption, transmission, or reflection...

An enclosure whose walls are coated to absorb completely all radiation striking them.

A cement used to reduce crosstalk in fiber optic bundles or plates.

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

The method of acquiring characteristic x-ray spectra from microscopic samples by use of the combination of a scanning...

The ionization that occurs in gas affected by the action of radiation quanta.

A lithography method that allows the transfer of fine-pitch gratings from a phase mask into photoresist. The exposure takes...

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

Standard maintained by the International Commission on Radiological Units as a unit of radioactivity defined as the quantity...

A lightproof box used for storing photosensitive materials.

A multiple-beam interferometer, usually consisting of two flat plates, with high reflective ability. The plates are set...

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

A semitransparent mirror in an optical system that combines two or more output beams into a single coaxial beam.

The engraving of a surface by acid, acid fumes or a tool; a process extensively used in the manufacture of reticles.

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

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

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

Magneto-optics refers to the study and manipulation of the interaction between magnetic fields and light (electromagnetic...

Optical coherence tomography (OCT) is an imaging technique used in medical diagnostics and biomedical research to obtain...

Behaving as though characterized by a series of waves having planes of vibration oriented at all possible azimuths.

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

Any of a number of instruments that uses a flame to vaporize a solution of the chemical being analyzed so that light may be...

The condition of the numerical aperture or beam diameter of the laser, LED, or other optical source being larger than the...

Edge enhancement with a directional characteristic.

Micro-robotics refers to the field of robotics that involves the design, development, and application of miniature robotic...

A finite version of Shannon's sampling theorem that states that a class of functions can be reconstructed exactly by a...

A method for measuring the index profile of an optical fiber by measuring the reflectance as a function of position on the...

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

Amplifier in which the input and output pulse heights are directly proportional.

A chemical substance that exhibits fluorescence when excited by ultraviolet radiation, x-rays or an electron beam. The...

1. In relation to cathode-ray tube displays, errors in the signal's amplitude, phase or both that result in small, rapid...

In aerial photography, the ratio derived from a stereoscopic pair of photographs that represents the air-base length divided...

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

A parallel plate of glass in such a position that the refracted and reflected rays of incident parallel light are mutually...

A reflecting surface that scatters radiation that is incident on it, thus producing diffuse reflection.

Relative to a light source, the frequency at which the source appears to fluctuate in light intensity half the time and...

A material used in the jacket of fiber optic cables.

Ablation applied to polymers and chemical solids. Process of material removal that minimizes edge damage but will not heat...

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

A reflecting grating ruled on a concave spherical surface that not only disperses the light but focuses the spectrum. The...

A holographic plate coated by photopolymeric mixtures that are composed of one or more monomers and a photoredox catalyst...

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

A prism made up of two air-spaced components. It has the ability to revert, and not invert, an image, and can be used in...

An excited energy state of an atom or atomic system that has a longer lifetime than the ordinary excited state and typically...

A support device in which a column or chamber of air permits the free travel of a mobile part. In optical mounting and...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic...

Structural surfaces that incorporate an embedded sensor network capable of detecting flaws within the structure.

A rotating chamber that can be spun at different speeds to generate great radial forces used to simulate different gravity...

A scanning probe microscope that analyzes the surface of a specimen by recording the intensity of light as it is focused...

Metabolic imaging refers to the visualization and quantification of metabolic processes within living organisms, tissues, or...

Sharp and narrow absorption lines found in the spectra of stars. They result from the absorption of a part of a star's...

A pulsed dye laser in which the excitation is provided by means of a flashlamp. Output is tunable from 335 to 850 nm, with...

A method of coding information in a communications system where the shift in the phase of an electromagnetic wave represents...

A multimode laser characteristic defined as the ratio of power loss for the second mode to that of the lowest mode.

A double meniscus system in which two achromatized meniscus lenses are arranged symmetrically on either side of the aperture...

The ratio of the intensities of a light bundle before and after passing through the lens.

In a microscope, the physical distance between the focal points of the objective lens and the eyepiece. The standard tube...

Color resulting from the interference between two light beams.

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

Also called complementary dominant wavelength. On a chromaticity diagram, the wavelength on the spectrum locus that lies on...

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

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

Acronym for profile resolution obtained by excitation. In its simplest form, probe involves the overlap of two...

The ratio of diffusely transmitted flux to incident flux.

A projection printer that is capable of reproducing a multiplicity of images from a master transparency on a single support...

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

A compound lens, the dimensions and materials of which have been so chosen that the lens is appreciably free of aberrations.

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

An optical material used in place of crown glass to produce lenses with extraordinary correction of chromatic aberrations....

A microscope designed so that the specimen is located face down above the objective.

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

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

A visual spectrophotometer with a rhomb located directly before the entrance aperture of a constant-deviation...

Wide-field, low-magnification device that consists of two compound microscopes focused on a single object, producing an...

Fiber that emits luminescent radiation excited by ultraviolet, x-ray or high-energy particles.

The angle formed between the normal to a surface and the reflected ray. This angle lies in a common plane with the angle of...

Radiation that occurs perpendicular to the plane of the radiation device.

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

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

Decibels referenced to one milliwatt; often used to specify power ratings for semiconductor diode lasers.

The process or device by which more than one signal can be sent over a single channel by using different time intervals for...

An optical source that has a luminous distribution that is uniform for all directions.

The storage of data as bits in memory by holographic processes. The laser beam is divided into reference and object beams,...

The light flash that occurs when an electrical field is applied to a phosphor already excited by ultraviolet radiation.

The large, usually flat surface onto which an image is projected for viewing. May be reflecting or transmitting (rear...

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

Liquid crystal on silicon (LCoS) is a display technology that combines liquid crystal materials with silicon-based...

In microscopy, the chamber that is contained on a microscope slide to hold a certain amount of fluid. It is calibrated...

The difference in angular bearing of an object as seen by the two eyes, due to the separation of the visual optical axes.

An electroradiographic process that uses ionization of air by x-rays as a basis for forming electrostatic images.

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

The measurement of surface temperature by a thermograph that forms a pattern of the heat radiated by the surface on a...

Convex is an adjective used to describe a surface or shape that curves outward, bulges, or has a rounded and outwardly...

A grating with very coarse rulings to match the long wavelengths in the far-infrared region. In the most efficient ruling...

The emission of radiant energy in which the energy emitted originates in the thermal motion of the atoms or molecules of the...

The science that deals with the measurement of optical absorbance (i.e. optical densities) over microscopic areas of a given...

Topology is a branch of mathematics that focuses on the properties of space that are preserved under continuous...

The radio waves of the electromagnetic spectrum that have frequencies of up to 10,000 megacycles per second.

The optical reconstruction of image information contained in a sound field. First the diffraction pattern, formed by an...

A material in which the refractive index varies according to changes in the light to which it is exposed. Lithium niobate is...

A process involving the interaction (absorption, emission or both) of two or more photons with a molecular entity.

1. To influence to a single direction. 2. Voltage that is applied to a solid-state device.

Short-distance scattering of light in holography caused by random index inhomogeneities and the developing index that...

An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the...

With respect to display systems, a device that uses an independent light source and a control-layer medium, the active...

In the context of electronics and semiconductor manufacturing, a wafer refers to a thin, flat disk or substrate made of a...

The minimum of change in stimulation needed to effect an awareness of change in sensation that is statistically determined.

A type of photoconductive detector in which germanium, usually doped with boron, gallium and indium, serves as a...

E.I. duPont's trade name for a polyester film. The most practical beamsplitter for use beyond the 15-µm wavelength...

An optical filter is a device that selectively transmits or blocks specific wavelengths, or colors, of light. Optical...

A unit of measurement of luminous intensity based on a physical standard, a set of calibrated carbon filament lamps. The old...

Sapphire can refer to either a gemstone or a specific type of crystalline material commonly used in various industrial...

In an optical waveguide, that loss attributable to macrobending. Macrobending usually causes little or no radiative loss.

Particle acceleration refers to the process by which charged particles, such as electrons or protons, gain kinetic energy...

A photographic emulsion of the silver-halide type that is used to record the path of a charged traveling particle. The...

Device in which the various circuit elements are fabricated in different substrate materials and then appropriately joined...

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

An opaque projector is a device used for enlarging and projecting images from opaque objects such as printed pages,...

The region of a ferroelectric crystal where spontaneous polarization is uniformly directed.

That property of a material that determines its ability to release electrons when absorbing photons.

The reflection in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

In a fiber optic cable, the longitudinal length required for the transmission media, wrapped around a central member, to...

The photographic filming of the action of x-ray images recorded on a fluorescent screen by means of large lens apertures and...

A strand of aramid yarn, steel or fiberglass in an optical cable intended to prevent bending or stretching that would damage...

Elastic scattering that occurs when inelastic processes eliminate particles from the beam.

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

In image processing, the location of edges by employing templates that respond to the first or second derivative of...

A type of conducting surface or material used to reflect radiant energy.

A gas laser in which the energy-state transitions between vibrational and rotational states of CO2 molecules give emission...

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

Reflection losses incurred at input and output of optical elements because of the difference in refractive index between...

A CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and...

1. The sector of the Earth's surface registered upon a remote sensing device in a satellite. 2. The amount of space occupied...

A spectrum having some lines that are darker than others or that contrast against a light, continuous-spectrum background.

High-modulus elastic fibers that exhibit the following differences from conventional elastic fibers: Increasing temperature...

The heat-treating method in which the index of refraction of glass is fixed near or at its maximum value by holding the...

A blank to which a piece of glass of a different refractive index will be fused to form a multifocal lens.

Pertaining to radiation or particle emission, whereby the emission is produced with minimal energy spread.

Image sensors in a two-dimensional configuration of rows or columns.

A telescope that is fixed or has a limited degree of movement in a vertical plane; primarily used to determine the position...

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

An airspaced achromatic doublet telescope objective.

A common technique in microscopy, oblique illumination is one in which the object is illuminated by a light source that is...

The letter form used on visual performance test charts. The overall letter height is equal to five times the thickness of...

A type of video signal in which the luminance and chrominance portions of the signal, or the luma and chroma, have been...

A device that serves to emit light of the same wavelength as the input light, only with an increase in intensity. It may be...

Any source that emits radiation of wavelengths between 100 and 300 nm. Instruments used to study these sources must be...

A chemical detection technique used to measure molecules that have a magnetic dipole moment. The analysis is directed to...

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

A type of receiver utilizing a local oscillator phase-locked to the incoming signal.

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

Study of the reflection or transmission properties of specimens as a function of wavelength.

The hydrogen-derived, ultraviolet radiation running from 1216 to 512 A, discovered by Theodore Lyman in 1914.

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

A device that uses electromagnetic fields to separate electrically charged particles according to their masses. As a beam of...

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

An automatic scanning instrument that is used to study a substance's fluorescence over a wide range of wavelengths. It...

Astronomical detector consisting of a photocathode isolated from the target by a coin value from which electrons are focused...

A technique, involving spectrophotometry in the ultraviolet, that is designed to determine the colors of thin-layer...

The ratio of the speed of light in a vacuum divided by the speed of light in the medium.

For any point on a thermal radiator, at thermal equilibrium and for each wavelength, the emissivity in any direction is...

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

A wide-field multiobject spectroscopy system used in astronomy, in which a bundle of low-loss optical fibers positioned on...

1. A plane that forms one side of the groove ruled on a diffraction grating. 2. To form the individual grooves of a grating...

That point on the optical axis of a lens, to which an incident bundle of parallel light rays will converge.

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

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

The splitting or shifting of spectral lines or energy levels caused by the application of a strong transverse electrical...

A system used for measuring direct solar radiation.

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

1. Generally, an emulsion mask having a clean annular region in an otherwise opaque region. It is designed to eliminate...

An instrument designed to measure the numerical aperture of an objective.

A graphic depiction of the loci of all points in space relative to a laser transmitter at a specific altitude.

Sometimes referred to as the surface normal or 'surface norm'; the normal is an axis that forms right angles with a surface...

Tip-enhanced Raman scattering (TERS) is a powerful technique that combines Raman spectroscopy with the enhanced spatial...

A superthin, highly reflective mirror.

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

The degree to which a pixel in a digital image represents the analog brightness of the corresponding point in the original...

A primitive crystal possessing two plane surfaces that form a dihedral angle bisected by another plane surface.

The condition of identity of visual appearance.

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

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a...

A cooling system used to attain and maintain desired low temperatures in infrared systems. The Stirling type is a mechanical...

The structure that holds the photographic negative in a proper position that is both flat and parallel to the lens plane, as...

Quantitative phase imaging (QPI) is an advanced imaging technique used in microscopy to measure and analyze the optical...

A pixel, short for "picture element," is the smallest controllable element of a digital image or display. It is a...

1. A device used to trace out an object and build up an image. One of the most common of these types is video scanning. The...

Radiation having waves that are out of phase in space and/or time.

The process of producing a visible two-dimensional image of a scene that is dependent on differences in thermal or infrared...

A technique for measuring the concentration of any gases. Identical infrared beams are alternately chopped, one passing...

In positioning, rotation about the line of sight or direction of travel.

The study and photographing of microscope specimens in ultraviolet light; using an optical microscope containing fluorite...

Essentially, noise that cannot be predicted. Therefore, even if the magnitude of sound or oscillation in a system is known...

1. A flaw in a blank caused by folding the blank's surface during its formation. 2. The change in the direction of a...

A photon jet is a narrow, highly collimated beam of light that is formed when light interacts with small dielectric...

A telescope with a concave paraboloidal objective mirror and a small plane (diagonal) mirror that reflects rays from the...

A type of transversely excited laser with a uniform arc-free discharge of large cross-sectional area that can be scaled to...

An optical instrument containing a gimballed sighting telescope, used to measure angular relationships in horizontal and...

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

Measures by heterodyning interferometry the local slope of a vibrating sample. The method allows the reconstruction of a...

A modulator is a device or component that modifies a carrier signal in order to encode information for transmission over a...

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

The difference between the energy of an atom in its ground state and that of the same atom in its excited (quantum) state.

Also referred to as a funduscope, an ophthalmoscope is a specialized instrument used by ophthalmologists for observing and...

Dichroism refers to the property of certain materials to exhibit different colors or absorbance of light depending on the...

The center of the sphere of which the surface of a lens or mirror forms a portion. Each curved surface of a lens has a...

A Bose-Einstein condensate (BEC) is a state of matter that forms at temperatures close to absolute zero. It is named after...

Computerized lens design algorithm that permits the lens MTF characteristic to be included and controlled during the...

Mie scattering, named after the German physicist Gustav Mie, refers to the scattering of electromagnetic radiation (such as...

With reference to electromagnetic radiation, the number of crests of waves that pass a fixed point in a given unit of time,...

A number that indicates the magnitude of the shift in a solid of positive and negative charges in opposite directions when a...

In a lens, the square of the radius of its aperture divided by the product of the focal length and the wavelength. It...

A contour mapping technique that involves projection of a grating onto an object to produce a shadow grating that is...

Optical glass refers to a type of glass specifically engineered and manufactured for use in optical components and systems,...

When uncontrolled laser energy leaks from a laser cavity prematurely, it causes serious damage to optical components and...

The high-speed electrons and positrons emitted by radioactive materials.

Application of radiation to an object.

That part of the cladding wherein the refractive index is constant within a specified tolerance, as a function of radius.

Means of determining the relative motion of a (seismic) mass or acceleration body from a stable laser operated system.

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

A device that provides simple and reliable laser power and energy measurement. Essentially a heat flux sensor producing an...

A departure from ideal paraxial imaging behavior. The distortion of an optical field wavefront as it is propagated through...

A lens designed for projection of color transparencies.

An emulsion that can record colored light.

That process by which radiation spontaneously emitted by a volume of optical materials is resonantly reabsorbed within the...

An optical reflector with the reflective coating applied to the front surface of the substrate. This eliminates the ghost...

A display format consisting of small light-emitting elements arranged as a two-dimensional array. Various elements are...

The term used in reference to vacuum systems using oil and diffusion pumps, describes the migration of pump fluids and their...

A term referring to an optical force field used to trap and stabilize particles acted upon by a force such as laser light.

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

The formula describing the spectral radiant emittance of a perfect blackbody as a function of its temperature and the...

An array of refractive microlenses that are round, square and hexagonal and as small as 15 µm. They are used for...

Parametric measurement for elliptical fiber and cable expressed as a ratio of the two-directional flow of power through the...

Electric polarization characterized by homogeneous polar dielectrics and ascribed to the position of the permanent molecular...

A plastic disc coated with ferric oxide or other films on which data can be stored by selectively magnetizing areas of the...

A process, either naturally occurring or mechanically induced, whereby water is changed from its liquid state into a vapor.

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

An infrared-transmitting optical fiber with a hollow core; it can be square, round or rectangular in cross section. Capable...

A source of light will not cast a distinct shadow of an interfering, opaque object, but will cast a shadow having two parts:...

A high-speed cine camera that produces discrete frames of a continuous event as opposed to the flow photographic record of a...

The desensitization of the first photographic exposure after it has been subjected to high-intensity radiation.

A camera system in which the image formed on the fluorescent screen of an image converter tube in the system is recorded by...

That branch of science involved in the study and utilization of the motion, emissions and behaviors of currents of...

The application of coating without heating of the substrates.

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

The thin edge of a refracting prism; the line of intersection of two refracting surfaces of a prism.

The error inherent in spectral energy or spectrophotometric quantity due to the finite dimension of the entrance and exit...

The capability of the spatial distributions of incident and reflected flux to interchange completely without alteration of...

That viewpoint at which the angular subtenses of points in the picture are identical to angular subtenses of the original...

A facility selected by mutual agreement of the user and the prospective vendor to test a prototype before it is offered for...

A probe card is a testing device used in the semiconductor manufacturing industry to evaluate and test the electrical...

A laser resonator in which a mode oscillating between the mirrors will converge upon the laser's longitudinal axis.

The use of computer analysis in the calculation of diffraction patterns for information on the design of optical systems. In...

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

For a particular mode, the reciprocal of the rate of change of the phase constant with respect to angular frequency.

An erecting prism that inverts and reverses the image. It displaces the optical axis but does not deviate it.

A device used to detect radiant energy by means of the thermal expansion of gas.

In an optical system, the space between the object being viewed and the system entrance pupil.

A disc, having opaque and transparent sectors or sectors with unlike reflectances, that is rotated at a specific rate to...

The point spread function (PSF) is a fundamental concept in imaging that describes the response of an imaging system to a...

The mean square difference in refractive index for two separate points in space.

One of the electrodes used to focus the electron beam of a cathode-ray tube. As the electrode's voltage is changed, its...

The point of intersection of the optical axis with any centered optical surface.

A technique used to create a series of interrelated holographic images that give an appearance of motion when projected in...

The creation of a planned sequence of data input that is obtained while airborne for use in aerial photogrammetry and other...

A photovoltaic cell, commonly known as a solar cell, is a semiconductor device that directly converts light energy into...

A technique for depositing a material coating on metal, ceramic, semiconductor or polymer substrates. The interaction of...

A lens that has one convex surface and the other concave.

A nonmagnetic instrument utilizing an electrofocus and deflection tube with a photocathode for imaging purposes. The optical...

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

The ratio of the intensity of the total radiation reflected from a surface to the total incident on that surface.

A device that is designed to automatically turn electric lamps on and off in a rapidly repeating sequence. The device may...

The positive ion current created in an electron tube as a result of the collisions between electrons and residual gas...

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

In an optical system having astigmatism, the distance between the tangential and sagittal image planes.

A spectrophotometer that measures the amount of ozone in the atmosphere through a comparison of solar energy at two...

In general, changes in one oscillation signal caused by another, such as amplitude or frequency modulation in radio which...

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

The distribution of gray-scale values in an image.

In a cylindrical lens, the meridian parallel to the generating lines of the cylindrical surface. In a toric lens, the...

The Foucault test is performed by moving a knife edge laterally into the image of a small point source. The eye, or a...

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

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

A fiber laser is a type of laser in which the active gain medium is an optical fiber doped with rare-earth ions such as...

The arrangement of two Porro prisms so that the inverted image formed by certain types of optical instruments is the same as...

A device that determines the lens shape in the cutting or edging phase of fabrication. It also is used to denote the...

Frame rate refers to the frequency at which consecutive images, or frames, are displayed in a video sequence. It is...

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

A laser-pumped crystal with nonlinear optical properties inside of an optical resonator in which the output generates...

In vivo is a Latin term that translates to "within the living." In scientific contexts, particularly in biology and...

The restricting aperture located at the front of the lens. It is usually defined as the maximum diameter of the entrance...

A term pertaining to devices (generally optical) designed for use with both eyes viewing through a single exit pupil. The...

The luminescence of a substance that is produced by energy within it (e.g., radioactive material).

An interface in an optical network that permits an optical signal to pass without changing the optical signal to an...

An instrument that is used to chart x-ray diffraction patterns, such as an x-ray spectrometer having photographic or other...

A polishing machine designed to permit adjustment of the polisher speed and motion for the control of flat surfaces.

One or more optical elements – typically cemented together - in an optical system that are treated as a single group;...

A technique for detecting and measuring atmospheric pollution, in which an oscillating mirror directs half the incoming...

Correction of an optical system at four separate wavelengths. This correction, longitudinal and lateral, is possible with...

Term synonymous with refractive index liquid, but related more to tank or chamber immersion of crystals, fibers, lenses,...

A type of x-ray that is capable of deep penetration; its wavelength is about 10-8 cm.

The circuit that regulates an electron beam's deflection in a cathode-ray tube.

The law stating that the amount of chemical change produced is proportional to the amount of light absorbed. Actually, the...

A device used for measuring the height of clouds from a position on the ground. Measurement technique uses a vertically...

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual...

Laser peening is a surface enhancement technique used to improve the mechanical properties of materials, particularly...

In digital image processing, a subcategory of frame processing that treats each pixel in terms of its relationship to...

Sets of lenses (positive, negative and cylindrical) usually mounted in circular rims suitable for slipping into trial...

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

Any of several compounds capable of binding heavy-metal ions, thereby preventing interaction between the bound ions and the...

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating...

The temperature above which a ferromagnetic material becomes only paramagnetic.

A telescope that uses a reflecting objective to focus an image of a distant object at a focal point.

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light...

LiFi, short for light fidelity, is a wireless communication technology that utilizes visible light or infrared light to...

A subtractive colorimeter that expresses a liquid's or object's color as a combination of three colors. These colors are...

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

Characteristic of optical correlators in which invariance to more than one distortion parameter per axis of the processor is...

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 ground-based navigation beacon that emits pulsed signals which are picked up by aircraft making an instrument (blind)...

1. In a plane Cartesian coordinate system, the horizontal axis, or axis in the left to right direction. 2. In a quartz...

An extended bubble or seed on glass, elliptically shaped and more than one-quarter inch (6.3 mm) in length.

A chemical placed in a solution that will indicate when an excess of a substance or ion has been reached by coloring the...

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

The point of a chromaticity diagram that represents the chromaticity of a reference stimulus.

A technique based on the principles of laser trapping and used to manipulate the position of small particles by gradually...

The use of narrow bandpass filters and special photographic emulsions to discern features of a surface that would not be...

The angular relation between two light rays that originated at the same object point. Sometimes used to indicate the angle...

In television, the number of individual pixels that can be distinguished in a horizontal scanning line; also called...

A device used to control or block a light beam by means of the Kerr electro-optical effect.

A tough, durable, heat- and cold-resistant optical quality plastic used in injection-molded items such as streetlight...

An objective measure of an object's brightness that is derived from the ratio of the luminance of its lightest section to...

A type of surface-emitting laser diode that uses dielectric mirrors to produce surface emission. The laser cavity is...

Digital holographic microscopy (DHM) is an advanced imaging technique that combines holography and digital image processing...

A material used in photodynamic therapy that is retained selectively by tumor tissue when injected into the body; it then...

The addition to the information signal in communications of redundant bits that enable the originally encoded message to be...

In photonics, a lattice refers to a periodic arrangement of optical elements or structures, often on a microscopic or...

The plane diagram produced by plotting one of the three chromaticity coordinates (X,Y,Z) against another. The most common...

A bundle of rays that originates from an object point on the optical axis of a lens system.

Graphic representation of quantified values of image quality whose points all refer to images that are of a constant...

In a sequence of laser pulse emissions, the intitial pulse that often helps initiate a reaction at the target surface,...

A junction between semiconductors that differ in their doping level conductivities, and also in their atomic or alloy...

The study and the interpretation of the infrared emittances of celestial bodies and phenomena.

In a microscope, the optical assembly that focuses light on the specimen and into the objective.

The basis of color vision in the human eye. Three types of cones have been identified, each having a unique spectral...

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

A condenser composed of a paraboloidal reflector and used for dark-field illumination.

A process by which a plastic cell is molded around a glass lens or lenses to create a mount, eliminating the metal barrel...

A unique glass made up of nano-structured materials to create millimeter sized monolithic glass space-variant polarization...

1. One of the plane-reflecting surfaces on a multisurfaced polygon. 2. The cleaved end mirror of a laser diode's active...

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

A common form of high-precision, ceramic-based actuator capable of moving and measuring at the nanometer level.

An imaging process in which the single opening of a simple pinhole camera is replaced with many openings called,...

A process of color photography in which colors are added one to another in the form of light, rather than as colorants, to...

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

Bohr's formulation that every new theoretical principle must correspond to the salient classical predecessor. The principle...

The ejection of electrons from the surface of a solid by the absorption of a sufficient amount of photons.

Denoting a phase shift of 90°.

The qualities of color associated with hue and saturation, but not brightness or lightness.

Quantum key distribution (QKD) is a method of secure communication that utilizes principles from quantum mechanics to...

The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The...

1. An eyepiece or magnifier with a scale at its image plane. That scale is placed in contact with an object, permitting...

A method in optical character recognition in which a mobile light beam scans the outlines of characters for subsequent...

The ratio of the illuminance at the peak of the diffraction pattern of an aberrated point image to that at the peak of an...

A device employed to identify toxic agents lingering on the ground or in the air from up to three miles away, by using laser...

An LED, or light emitting diode, is a semiconductor device that emits light when an electric current passes through it. LEDs...

1. The sorting of lenses by their color. 2. In an optical system, an irradiance or brightness gradient in the image that is...

Electromagnetic radiation present upon the open aperture of the source within an operating environment.

The properties of certain materials that cause them to have relative permeabilities that exceed unity. This permeability...

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

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials...

Concave and convex spherical mirrors are types of curved mirrors that have surfaces shaped like segments of spheres. These...

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

Heatless light emissions from living organisms caused by the combination of oxygen and pigments such as luciferin.

A camera system that uses a fine powder to diffract x-rays from the specimen. A beam of monochromatic x-rays passes through...

A telescopic system having an eyepiece, a reticle and an objective. The instrument measures wavefront power in diopters.

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

An instrument for eye surgery that directs intense xenon arc light through the transparent cornea lens to the retina where...

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

Near the boundary or edge of the field of an optical system; the outer fringe.

The condition in which two or more energy states are identical.

A form of infrared CCD that utilizes internal photoemission as a photodetection mechanism.

Ratio, to the luminance of a test color, of the luminance of the spectrum color that matches the test color when mixed with...

A mixture of ionized gas and metal vapor generated by impingement of the laser beam onto a material being welded or a weld...

A device for detecting visual and infrared radiation using a photoconductor as the principle sensing element.

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

In the optical field, a tube to which a lens is fastened for centering.

The system of color classification and description produced by Wilhelm Ostwald.

A V-shaped channel pressed or etched into a substrate, in which, for example, optical fibers may be placed to create an...

The method of determining the energy distribution of high-speed charged particles by the luminous effect formed when the...

A camera containing an electronic image sensor that converts the image to an electronic signal suitable for television...

An optical grating, in the context of optics and physics, refers to a device with a periodic structure of closely spaced,...

A filter designed to decrease the luminosity of the sky without decreasing that of the landscape in the foreground. A filter...

Commonly known as CR39, this thermosetting plastic is used in the casting of eyeglass lenses because of its toughness and...

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

A camera capable of making successive exposures on a continuous film driven by accurately spaced sprocket holes (a motion...

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

A technique for detecting free radicals by their electronic spectra. The material to be studied is placed in a...

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

A light-interference device whose excitation is determined by the modulation of a light beam by an ultrasonic field.

Observed phenomenon in laser pulses in which a large number of excited electrons are created and in which multiphoton...

Characterizes a substance whose plane of polarization is rotated counterclockwise as the observer looks through the material...

The radiant energy emitted within a time period per unit solid angle, usually measured in watts per steradian.

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

Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in...

The ability of a camera to compensate in cases where a subject with a large amount of background light would otherwise be...

The product of exposure time and irradiance or illuminance.

One lumen-second, the SI unit of the quantity of light.

The range of angle or solid angle values by which light may enter an optical system.

The intensification of a latent image, because of exposure to light to which the emulsion is otherwise insensitive.

A phototube in which the primary photoemission current, before being extracted at the anode, is multiplied many times.

The subtractive imbibing process of transferring color prints on paper whereby the dyes from three separately prepared...

A mass-relieving method whereby material is removed through the sides of a reflector in a direction parallel to the surface....

The creation of free electrons within a solid by the absorption of a sufficient amount of photons. The effect produces an...

Technique that defocuses activity from surrounding planes by means of the relative motions at the point of interest.

The broadening of spectral lines due to the collision of radiating particles with one another and the resulting interruption...

A lens having an extremely high aperture and used in the recording of x-ray fluorescent screen images. It often is specially...

1. That portion of the aperture that functions to collect energy and deliver it to the final system detector. 2. For an...

The movement of the eye as it focuses on details of a scene. Some imaging systems mimic this movement by small, rapid...

The bands of spectral lines representing the electronic transition in a molecule.

The output of spectral channels written as an integral function of known solar irradiance, atmospheric transmittance and...

An optical system that uses refraction to form an image.

Naturally occurring planes in crystalline substances that provide easy points for separation.

A defect in infrared systems that appears as a dark circular area on a displayed image, caused by radiation reflecting into...

A homogeneous solid solution with crystal lattice sites occupied, at random, by the molecules or ions of two or more...

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

Mathematical compensation for the nonhydrogenic behavior of recombination radiation levels of gases, based on the quantum...

Laser active elements typically refers to the substances or materials within a laser system that play a critical role in the...

In a microscope, a space reserved to accommodate an optical filter or polarizer.

A digitized image consisting of just two brightness levels, as black and white, represented in memory as zeros and ones.

Glass consisting of almost pure silicon dioxide (SiO2). Also called vitreous silica. Frequently used in optical fibers and...

An imaging system designed to highlight small deviations in a planar reflective object such as a mirror. The system can be...

Family of deterministic models of plant canopy reflectance that provides deterministic formulation for each necessary...

A shift in the direction of the red in the spectral lines of light which, defined by the relativity theory, will have...

High-voltage, fast-discharge circuit named after its inventor, Erwin Marx. Its capacitors are charged in parallel and...

The adjustment of the eyepiece of an instrument to provide accommodation for the eyesight differences of individual...

Voltage that produces current flow in the direction of greater resistance to the steady-state direct current; i.e., from the...

In a telephoto lens, the ratio of the overall length to the focal length of the lens. It is generally about 0.8 to 0.9 in...

A type of birefringent polarizing prism that transmits the extraordinary ray and removes the ordinary ray through total...

Transmission in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

An imaging device whose technology contributes three specific advantages: ability to study large solid specimens that...

A compound lens combination whose astigmatic difference is zero for one or more off-axis zones in the image plane. In such a...

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

In a thermal imaging system, the change in temperature that yields a signal-to-noise ratio of unity.

The function that characterizes the quality of an optical system by denoting the modulation and spatial phase shift of the...

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

A digital imaging method whereby the first gray level in the ordered sequence and the position of the first lengths of all...

The law given by the formula: that is, the frequency of radiation emitted or absorbed by a system when E2 and E1...

A system that satisfies the Abbe sine condition, and is free from spherical aberration and coma.

Directed energy refers to a type of energy that is emitted and transferred in a controlled direction. The term is often...

Quantum-enhanced metrology refers to the use of quantum mechanics principles and techniques to enhance the precision and...

The photographic recording of an action by taking a series of still pictures at regular intervals throughout the action.

A detector sensitive only to signals close to or at a particular frequency that is the same as the frequency of a control...

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

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

The present radiation level within a laser or electromagnetic radiation operating area.

The formation of a distinct, irregular surface pattern on a photographic emulsion due to differential swelling of the...

The necessary increase of a photograph's exposure time as the result of the additional absorption of light by the filter...

A double-surfaced catadioptric spherical mirror whose spherical first surface consists of a negative meniscus (concave) lens...

The code used to describe the United States system of color telecasting.

In an image, the orientation and magnitude of the rate of change in intensity at any point.

A single number, defined by the computer program or the user that expresses the performance of an optical system. Also known...

The phenomenon that can render an optical resonator the equivalent of a semiconductor flip-flop. A bistable device will...

A photocathode that exhibits maximum sensitivity in the blue and ultraviolet regions of the spectrum. The sensitivity is...

An eyepiece combined with an erecting prism or lens system.

1. A compound lens consisting of two elements. If there is an air space between the elements it is called an...

An electronic device consisting of a semiconductor material, generally germanium or silicon, and used for rectification,...

A device designed to decrease flux density or power per unit area of a light beam through absorption and scattering of the...

A solid-state video detector consisting of a single row of light-sensitive semiconductor devices, used in linear-array...

Photographing of terrain on the ground and objects in the air by cameras mounted in aircraft; utilized in satellites,...

The determination of the temperature of a source by the detection of its incandescent brightness.

Any irregular motion, variation in intensity or change in color that arises because of atmospheric turbulence during the...

The scattering of charged particles, moving through matter, by the electrostatic force exerted by other charged particles.

Two-photon excited fluorescence (TPEF) is a nonlinear optical method that allows imaging of biological cells and living...

In vitro is a Latin term that translates to "in glass." In scientific contexts, particularly in biology and medicine, it...

Simulation of atmospheric turbulence for laboratory experimentation purposes, achieved by creating an unstable vertical...

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 crystal having identical lattice points.

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...

Chalcogenide refers to a class of compounds containing elements from group 16 of the periodic table, which includes sulfur...

A coherent optical fiber bundle in which the configuration is flat rather than round, giving an output in a line.

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

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

A medical technology that uses lasers or other light sources in combination with photosensitizing drugs to treat cancerous...

Optical fiber that transmits a greater percentage of input light than does high-loss step-index fiber. Low-loss fiber...

The chromatic resolving power of a prism is invariably stated for the case in which parallel rays of light are incident on...

Whispering gallery mode (WGM) refers to a phenomenon in wave physics, particularly in optics, where waves, such as light or...

A threadlike inclusion within a blank of optical glass. Rarely found in quality optical materials.

Temperature of the blackbody having chromaticity nearest to that of the test source on a specified chromaticity diagram.

Optical glass that possesses a refractive index equal to or less than 1.5, and an Abbe number that ranges from 62 to about...

A wave in which energy is focused near a boundary separating materials having different properties. Propagation of the wave...

A value used to designate the relative sensitivity of a detector. The higher the D* value, the better the detector.

Displacement in a direction perpendicular to that of the intended displacement, as in a translation stage with simple...

With respect to atomic fluorescence spectroscopy, the fluorescence that is emitted by an atom at a spectral line of a...

A compact optical projection system, mounted on or built into a helmet, and used to project data or a scene directly into...

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

A curve expressing an optical fiber's total transmitted power as a function of its launch angle at the input.

A type of glass used in telescope mirrors, formed by adding a nucleating agent to standard glass and then heating it until...

The study of chemical reactions stimulated by the properties of light.

Biometrics refers to the automated recognition of individuals based on their physiological or behavioral characteristics....

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

A system that determines whether an image is in or out of focus by means of a source of illumination at the conjugate focal...

In spectacle lenses, the lateral measurement of a multifocal segment at its maximum width.

A study of the energies and wavelengths of radiation emitted by atoms and molecules when particular physical conditions are...

A supporting member used to hold optical parts during grinding and polishing. It also describes the assemblage of optical...

Luminous flux incident per unit area of a surface; luminous incidence. (The use of the term "illumination" for...

Heterochromatic photometry that depends on the elimination of chromatic flicker at a lower frequency than luminance flicker.

Thermal interface materials (TIMs) are substances or compounds used to enhance the thermal conductivity between two surfaces...

A modified form of an image-retaining panel that can be used in subdued daylight. This is achieved by adding a layer of zinc...

Fusion ignition refers to the point in a controlled nuclear fusion reaction where the energy released by the fusion...

The graph of the oscillating variations composing the wave of a video signal.

A device that completely or partially restricts the amount of light reaching the eye.

In laser pumping, parasitic absorption that occurs at certain wavelengths, decreasing pump efficiency and gain.

The process of determining, with the aid of plane-polarized light, the stress distribution in materials under complex...

A plane passing through a crystal that has the optic axis of the crystal and the light ray under consideration.

A type of birefringent filter, similar in principle to the Lyot filter, consisting of many identical birefringent elements,...

The physical thickness times the refractive index.

A lens mounting with eccentric rings that may be rotated to shift the axis of the lens to a prescribed position.

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

The analysis and measurement of the fluorescence emitted by a source. Fluorometric processes are more sensitive than light...

The emission of light by thermal radiation of a temperature high enough to render the source of radiation visible.

The transfer of energy lost by radiation to the body, relative to the loss of energy per unit of path traveled.

Quotient of total luminous flux divided by total radiant flux; lumens per watt. (For a source, quotient of total luminous...

A closed-loop system that compensates for thermal blooming by optimizing only one parameter: the amplitude of the phase...

Ability of a laser to resist variations in output power caused when it is slowly rotated about its optical or symmetrical...

The law stating that the critical fusion frequency is approximately proportional to the logarithm of the luminance and the...

A type of compound microscope that uses three visible wavelengths to translate details produced by invisible radiation.

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

Modified chemical vapor deposition (MCVD) is a technique used in the fabrication of optical fibers. It is a specialized form...

Luminescence produced by the bombardment of radiant energy such as x-rays, radioactive waves or alpha particles.

A transparent sphere that has an index of refraction that is different from that of the medium surrounding it; used in...

Calorimetry is a branch of science that involves the measurement of heat flow in physical or chemical processes. It...

Also known as an eyepiece micrometer. A microscope eyepiece that has a finely divided scale ruled or photographed on a...

Freeform mirrors refer to reflective optical components that deviate from traditional symmetric or rotationally symmetric...

The law stating that the angle of reflection is equal to the angle of incidence, the incident ray, reflected ray and normal...

A fiber optic end plate constructed by drawing a bundle of parallel fibers embedded in glass and cutting it into thin...

Blocking by means of a pitch ring, pitch button or a totally pitched block. Pitch, containing a soft filter, may be used...

Any arrangement of a bundle of optical fibers that alters the shape of the image. For example, by systematic regulation of...

The condition in a multimode optical waveguide in which the relative power distribution among the propagating modes is...

A grating that specularly reflects the specified long radiation wavelengths and diffracts the shorter wavelengths off in...

A hologram formed without lenses and with the object and reference points sharing the same plane. In the initial recording,...

The spreading of potentially equal radiation frequencies that results in broadening of the spectral line. This effect is...

A scale on an optical instrument that indicates the condition of focus. May indicate the distance to the object or diopter...

The highest value of saturation possible for a specified hue.

An optical system used to examine the pharynx.

A scanning technique in which the object is illuminated the entire time, and in which picture elements of the object are...

Also known as display primaries. Colors formed by a television receiver that are of constant chromaticity and variable...

The central peak (including everything interior to the first zero or dark ring) of the focal diffraction pattern of a...

A light-sensitive resistor in which resistance decreases with increase in light intensity when illuminated. The device...

See optical spectrum; visible spectrum.

The use of thin flexible glass or plastic fibers as wave guides — or "light pipes" — to channel light from one...

Resonance can be defined in various contexts, including physics, chemistry, and music. Here are definitions for resonance in...

An optical gate typically refers to a device or system that controls the transmission of light, allowing it to pass through...

A type of filter consisting of a series of birefringent crystals and polarizers invented by French astronomer Bernard Lyot...

In fiber optic cable, containment of the fiber or fibers within an outer protective tube in which they can move to some...

A method of analysis in which a pulsed laser beam is used to heat a particle, producing a plasma, or laser spark. As the...

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

A colorimeter is a device used to measure and quantify the color characteristics of an object or a light source. It provides...

A uniaxial, birefringent crystal having an ordinary ray with a higher velocity than the extraordinary ray.

The principle that electronic energy transitions occur at such speeds that the nuclei of the atoms in the molecular system...

A monochromator is an optical instrument used to isolate and select a narrow range of wavelengths from a broader spectrum of...

The formation of an interferogram by means of two holograms on the same recording medium, often used for determining small...

An extremely wide emission spectrum generated by the nonlinear effects created when a high peak power from a short-pulse...

Electromagnetic energy that is capable of producing photochemical activity.

Any isolated wave that propagates without dispersion of energy. Specifically to photonics, an ultrashort pulse of laser...

The real numerical aperture (NA) of a fiber when the computed NA is not valid because of change in the glass indices during...

The reversal of a developed image due to the exposure of the partially developed image to actinic light.

An electron-beam tube designed so that the beam can be carried through a portion of the wall of an evacuated enclosure.

The efficiency of scattering by an atom in a particular direction, expressed as: where AA is the amplitude of the wave from...

The temperature at which the solid phase of a material is in equilibrium with the liquid phase, or when the material changes...

An advanced magnetic device used in x-ray lithography to beam x-rays onto the surface of silicon wafers used for...

Interferometric modulator display (IMOD) is a type of display technology used in electronic devices, known for its energy...

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

The ratio between the focal length of a lens having a longer focal length than that of the standard lens used with a camera,...

Ratio of the radiant flux at a particular wavelength lm to that at any other wavelength l, such that both radiations produce...

A multilayer filter that passes only a narrow band of wavelengths.

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 series of capacitors and inductors connected to the flashlamp in a pumped Nd:YAG laser system in order to regulate the...

In hybrid or monolithic integrated circuits, the laser ablation of a portion of resistor material to achieve the design...

Equipment that supports microscopic live-cell imaging by managing the gas, media perfusion, temperature and other factors to...

The highest frequency at which a laser diode can be driven and still be modulated acceptably that further results in the...

The use of an applied electrical field to focus a cathode-ray tube's electron beam.

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

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

A lamp that yields a nonluminous flame; used in the spectroscopic analysis of radiation emitted by a substance placed in the...

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

A specific type of storage in which the material to be written on is heated above its transition temperature and switched in...

A crucible made of electrically resistive material through which a current is passed to heat the material inside, which then...

An otoscope is a medical device used by healthcare professionals, particularly ear, nose, and throat (ENT) specialists,...

Direct conversion of a photon from one wavelength to a lower energy photon of another wavelength(s) due to inelastic...

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

A specific form of phase shifting interferometry - commonly referred to as multiple wavelength phase shifting interferometry...

The technique of producing spectrograms in wavelengths beyond 120 nm by the use of a diffraction grating and a Schumann...

A prism that often is used as a dispersing element in spectrographs and monochromators.

In a semiconductor, the state created by the addition of a dopant that provides excess electrons.

An instrument designed to give precise and rapid detection of changes in tumor growth as well as the location of small...

The amount of energy required to raise the energy level of an atom; a necessity if the atom is to radiate energy. High...

Combination of Beer's and Lambert's (absorption) laws.

A prism with curved faces that collimates, reflects and refracts incident light. Often used in the production of...

The term half bandwidth (HBW) generally refers to the width of a spectral band or frequency range at half of its maximum...

A hologram formed by the recording of a plane object situated in the focal plane of a lens so that each object gives rise to...

The sensations of hue and saturation, taken together, but not brightness or lightness.

A mechanical or electronic device used to control the amount of time that a light-sensitive material is exposed to radiation.

The lens located at the object end of a microscope tube. A wide range of objectives is available, including simple...

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

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

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

Indium phosphide (InP) is a compound semiconductor material composed of indium (In) and phosphorus (P). It belongs to the...

A flat cylindrical device generally used to polish terminated ends in fiber optic connections.

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