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

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

The perception of visual stimuli at the left and right outer boundaries of the visual field.

An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the...

A gyroscope is a mechanical device consisting of a spinning disk or wheel mounted on a spinning axis in such a way that its...

In a lens, the square of the radius of its aperture divided by the product of the focal length and the wavelength. It...

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

The high-speed electrons and positrons emitted by radioactive materials.

A three-dimensional hologram.

A system used for measuring direct solar radiation.

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

The use of a tightly focused beam of electrons to drill minute holes in substances. The drilling is accomplished by the...

1. The range of frequencies or wavelengths over which radiations are absorbed or emitted in a transition between a specific...

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

In photography, the technique of taking multiple pictures of the same subject at different exposures to compensate for...

In optics, an image is the reconstruction of light rays from a source or object when light from that source or object is...

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

Plasma formed by heat radiation from the sun.

A machine vision technique that compares a template of the desired image (the correlation kernel) with the actual camera...

The principle stating that two diffraction screens, one being exactly the negative of the other, will form the same...

A line-scan camera, also known as a line-scan image sensor or linear array camera, is a type of digital camera designed to...

An extremely wide emission spectrum generated by the nonlinear effects created when a high peak power from a short-pulse...

The effect whereby a light beam is deflected by a birefringent prism when its polarization is changed by voltage applied to...

The distortion created because the different frequencies of a signal have different propagation velocities through a medium.

A large-scale, precise drawing of the contours of a perfect mechanical part, often with plus and minus tolerances drawn or...

A calculated measure of the ability of an incident force to cause an object to spin. The spin speed of any given object is a...

A series of solar cells arranged to collect solar radiation and to generate a given amount of electrical energy.

A Huygenian eyepiece containing a pointer at its focal plane that is used -- when viewing an object through the eyepiece --...

Process of synthesizing long molecular chain materials (polymers) by reaction of many small molecules (usually thousands)...

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

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

The analysis of metal structure using an optical or electron microscope, generally with a camera, to record observations.

Optical aberration such that image magnification varies with ray distance from the optical axis in a radial distortion.

Common name for a variety of adhesives used for lens bonding, fiber optic splicing and other photonics applications. The...

The clarity of an optically reproduced image. Definition is produced by the combination of resolution and acutance.

The combination of the audio and visual signals that are transmitted and received at the same time, correlating the scene...

The probability that an atom in one state will move spontaneously to a lower state within a given unit of time.

Spectroscopy is a technique used in the study of interactions between matter and electromagnetic radiation. It involves...

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

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

A device used to delay transmission of a signal for functions such as memory loops, sequential processing or built-in...

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

A term pertaining to devices (generally optical) designed for use with both eyes viewing through a single exit pupil. The...

An optical projection device designed to project positive color transparencies onto a screen for viewing.

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

Freeform mirrors refer to reflective optical components that deviate from traditional symmetric or rotationally symmetric...

Fusion ignition refers to the point in a controlled nuclear fusion reaction where the energy released by the fusion...

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

The thin edge of a refracting prism; the line of intersection of two refracting surfaces of a prism.

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

A structured light device using a rapidly rotating laser to project a beam of light that appears to the human eye as a...

A computer-generated hologram (CGH) is a holographic image produced using computational methods and algorithms, rather than...

An embossed or marked disk, constructed out of a transparent material and used with a camera system to soften an image.

Factor that relates the pulse spread occurring in a graded-index fiber to that of an equivalent step-index fiber having an...

Reflectance confocal microscopy (RCM) is a non-invasive imaging technique that allows for high-resolution, in vivo imaging...

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

A mathematical transformation used in image and video compression that changes two-dimensional representation of data into...

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

The area of optics in which the wave nature of a particle is exploited to carry out very accurate interferometry and other...

An impurity in a material that is capable of inducing electrical conduction in that material by transferring an electron to...

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

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

A specific type of storage in which the material to be written on is heated above its transition temperature and switched in...

The frequency domain is a concept used in signal processing and analysis to represent signals and data in terms of their...

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

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

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

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

Gallium arsenide phosphide (GaAsP) is a semiconductor alloy composed of gallium (Ga), arsenic (As), and phosphorus (P). It...

A device used to determine the location and attitude with respect to the Earth of orbiting spacecraft by detecting the...

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

Similar to LASCR, except that all four regions are available.

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

Also duty factor, duty ratio. The product of the pulse duration and the pulse repetition frequency of a wave composed of...

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

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

An isotope of cesium that emits negative beta particles and has a half-life of 2.19 years; its applications include...

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

In a single element, any lack of coincidence between the optical and the mechanical axes. In a lens system, any lack of...

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

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

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

Photogrammetry is a technique used to obtain accurate three-dimensional measurements of objects and environments through the...

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

A surveying device used to measure vertical displacement of target centers of scale lines from a horizontal plane generated...

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

In laser welding or heat treating, the instantaneous laser beam power per unit area. This parameter is key in determining...

A passive device, having three or more ports, in which input light from one port is coupled only to the next sequential port...

A type of motor that acts as the control element in a servomechanism. It is powered by an amplifier circuit and drives the...

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

In a waveguide, a change in direction of the axis without deviating from the plane of polarization.

A cement used to reduce crosstalk in fiber optic bundles or plates.

Prediction based on observations of nuclear masses in the valley of stability that indicates the maximum number of electrons...

A means of high resolution study through the application of soft and hard x-rays onto a sample surface in order to obtain...

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

In optics, a motion controller refers to a device or system that precisely controls the movement of optical components, such...

A type of birefringent filter, similar in principle to the Lyot filter, consisting of many identical birefringent elements,...

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

Phenomenon caused by an ultrashort and ultra-intense light pulse propagating in a Kerr medium, such as air or water. When...

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

In television system specifications, the number of parallel horizontal black and white lines of equal thickness, that can be...

The term delta error (delta-E) generally refers to the difference or change in error between two values or states. The word...

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

An atomic clock is a highly precise timekeeping device that uses the vibrations or oscillations of atoms as a reference for...

A photodetector composed of a photoconductive material that, when exposed to radiation, conducts without the aid of added...

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

Flux per unit area measured normal to the direction of propagation of the flux.

A caustic formed by reflection.

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

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

The Mills Cross telescope is a two dimensional radio telescope in which the two antenna arrays are positioned perpendicular...

The term "excimer," strictly used, refers to excited species made by combination of two identical moieties, atoms...

A rapid change, as opposed to a long-term drift, of the emission wavelength of an optical source. Chirping is most often...

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

A relatively hard crystal, highly resistant to excessive energy radiation, that is frequently used for optical windows,...

A snapshot representation of the final image created by a computer program.

Operation in which the minimum detectable signal is set because of variations in the average signal current; e.g., quantum...

A lens aberration that causes axial light rays having different wavelengths to focus at various points along the axis.

The analysis and measurement of celestial bodies, their motions and positions.

A fiber optic gyroscope (FOG) is a type of gyroscope that uses the interference of light waves to detect changes in...

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

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

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

A process of isolation of various atom vapor ions by means of tuning a laser source. For example, laser enrichment is...

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

A device that is designed to automatically turn electric lamps on and off in a rapidly repeating sequence. The device may...

A system of local area networking in which each node or station is connected to two others, ultimately forming a loop. Data...

Description of an optical system in which all the elements are aligned on the same axis.

A measure of the ability of a photographic system to record fine detail. Usually stated in terms of cycles per millimeter on...

Typically represented by the Greek letter μ, magnetic permeability is the measure of a material's ability to generate and...

A hologram that is formed on a recording medium by changing the phase of the illuminating wave in correspondence with the...

Neuromorphic refers to the design and development of computing systems or devices that are inspired by the structure and...

A semiconductor device that functions as an electrically controlled switch for AC loads.

The highest value of saturation possible for a specified hue.

The interaction of superimposed light from two separate sources that results in a combined intensity that is less than the...

A galvanometric scanner, also known as a galvanometer scanner or galvo scanner, is a type of optical scanning device used to...

Wide-field fluorescence microscopy uses either naturally occurring structures or staining with fluorescent tags that are...

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

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

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

The mean square difference in a spatial parameter at points spaced a given distance.

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

Light diffracted by a solid (usually quartz in crystal or fused form) traversed by acoustic waves. If the ultrasonic...

A polariscope with a half-shade device and an angular scale generally attached to the analyzer. It is used to measure the...

In rangefinders and height finders, a rotatable or sliding wedge-shaped element used to divert the line of sight precisely...

The reversible change in the absorption spectrum of certain compounds upon irradiation with a given wavelength of light.

A contour mapping technique that involves projection of a grating onto an object to produce a shadow grating that is...

Successive layering of resistive, dielectric and conductive inks on a substrate by a type of screening process.

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...

In a laser, the optical resonator formed by two coaxial mirrors, one totally and one partially reflective, positioned so...

A lithography method that allows the transfer of fine-pitch gratings from a phase mask into photoresist. The exposure takes...

The maximum number of users who are using a given communication channel. Typically, the number of users at any given time is...

Metasurfaces are two-dimensional arrays of subwavelength-scale artificial structures, often referred to as meta-atoms or...

An instrument used to measure expansion of solids, liquids and gases.

Piezoresistance is a phenomenon in materials science and physics where the electrical resistance of a material changes in...

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

Intensity of emission as a function of direction in a given plane.

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

Capable of being penetrated by some form of radiation.

The phase change of one of the two split beams of an interference microscope.

The angle through which a beam is deflected.

A camera that consists of a concave spherical mirror with an aspheric plate situated at the center of curvature of the...

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

A device used in the sputtering of thin films, in which a magnet system on the back of the cathode deflects the electrons,...

A lamp that emits light as the result of the passage of an electrical current through ionized cesium vapor.

Introduced into the laser beam from localized fluctuations in current density within the plasma itself. These fluctuations...

Property of a substance whose volume elements differ in composition and optical properties.

Characteristic of dissimilar metals in thermoelectric solar cells whereby separate junctions exhibiting distinct...

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

A method of measuring flow velocity by seeding the flow with neutrally buoyant particles and using a pulsed laser to...

An infrared camera, also known as a thermal imaging camera or IR camera, is a device that captures and visualizes the...

An optical instrument designed to permit the visual examination of the interior of the bronchi.

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

Refers to micron-size complex machines that have physical dimensions suitable for the fabrication of optical switches for...

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

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

In image processing, mathematical operations that change spatial geometry, as for instance scaling, translating, rotating or...

Blaze height typically refers to a parameter in the context of diffraction gratings, which are optical devices consisting of...

A hologram that is illuminated by a source from the viewer's side.

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

A form of microfiche that has an information reduction ratio that is greater than 100 to 1.

A three-terminal semiconductor having only one PN junction and a stable, open-circuit, negative-resistance property.

The process or act of measuring the geometric properties of an object or image.

The ejection of electrons from the surface of a solid by the absorption of a sufficient amount of photons.

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

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

An electron tube that stores and visually displays information by means of a cathode-ray-beam-scanning and charge-storage...

Pixel pitch refers to the distance between the centers of two adjacent pixels on a display screen or imaging sensor. It is...

Luminescence is the emission of light from a source that is delayed by more than 10-8 s following excitation.

One of the two principal types of optical glass, the other being flint glass. Crown glass is harder than flint glass, and...

The emission of radiant energy produced by the passage of an electrical current through an appropriate electrolyte in which...

Functional materials refer to materials that possess specific properties or functionalities that make them suitable for...

A light therapy that utilizes nonionizing light sources, including lasers, LEDs, and broadband light, in the visible and...

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the...

The deflection of a beam of electrons, at regular intervals, across a cathode-ray tube screen, according to a definite...

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

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

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

A point cloud is a set of data points in a three-dimensional coordinate system, where each point represents a specific...

Q-switched operation, or q-switching, is a technique used in lasers to produce short and intense pulses of light. The term...

The lens located at the object end of a microscope tube. A wide range of objectives is available, including simple...

Spontaneous changes to the visual system making it more or less sensitive to light.

A measurement technique used for the rapid quantitative evaluation of surface quality based on the detection and analysis of...

A process involving the interaction (absorption, emission or both) of two or more photons with a molecular entity.

The study and interpretation of the spectra of substances after they have absorbed the radiant energy emitted by a brief,...

A metabolite is any small molecule that is a product of metabolism, the chemical processes that occur within living...

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

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

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

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

In a camera, the movement of one or more lenses behind the front lens, rather than of the front lens itself, to bring the...

1. In optics, the ability of a lens system to reproduce the points, lines and surfaces in an object as separate entities in...

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

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

A doubly refracting crystal having a single axis along which there is an absence of double refraction.

In a local area network, a unique signal that travels from one node or station to another, providing them serially with...

Laser ablation is a process that involves the removal or erosion of material from a target surface using laser energy. This...

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

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

A handheld, light-sensitive device that is used with a display console to directly change, measure or erase the visual...

A type of interferometer noted for producing narrow multiple-beam interference fringes. As a result, when compared with the...

The observation of specimens by a microscope linked to a television camera and an image processor.

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

That property of certain optical devices, e.g., a penta prism, that maintains the angular relationship between the entering...

An objective measure of an object's brightness that is derived from the ratio of the luminance of its lightest section to...

A device that serves to detect the presence of vacuum ultraviolet radiation. It may be photographic film, a thermopile, ion...

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

A telephoto lens form noted for its lack of distortion.

A mode of transmission whereby the sending and receiving stations operate continuously at a fixed relationship of phase and...

The study and utilization of interference phenomena, based on the wave properties of light.

A type of glass containing barium oxide, which is added to increase the refractive index while maintaining a relatively low...

Chirality is a property of certain molecules and objects in which they are non-superimposable on their mirror images. In...

An apparatus, designed for use with a camera, that is used to rapidly open the path from lens to film, to maintain the...

A material that can rotate the polarization of light that passes through it. An optically active material exhibits different...

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

A measure of the closeness with which an optical image is capable of resembling the original object. The factors that affect...

Also referred to as image visibility, the contrast of an image is the variation in the intensity of an image formed by an...

A method of manufacturing polycrystalline infrared-transmitting optical fiber by heating a single halide crystal billet and...

A configuration or device mounted at the end of a fiber or cable that is intended to prevent reflection.

1. In relation to cathode-ray tube displays, errors in the signal's amplitude, phase or both that result in small, rapid...

1. An optical device used for projection of enlarged images of transparencies or lantern slides on a screen. 2. A device...

An instrument that detects high-energy charged particles by analysis of the Cerenkov radiation that they emit.

Pockels cell or dynamic optical retarder in which the electrical field is applied in a direction parallel to that of light...

Light diffusion refers to the process by which light is scattered or spread out in various directions as it interacts with a...

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

In digital image processing, a subcategory of frame processing that treats each pixel in terms of its relationship to...

An atom that has gained or lost one or more electrons and, as a result, carries a negative or positive charge.

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

A standard for fiber optic data transmission systems being developed by the American National Standards Institute (ANSI) and...

Ratio of the luminous flux in a beam of radiation to the spectral radiant flux in the same beam at a given wavelength.

Fizeau fringes are interference fringes observed in an interferometer, specifically in a Fizeau interferometer. The Fizeau...

A type of radiation detector that depends on the ionization produced in a gas by the passage of a charged particle through...

A 45-90-45° reflecting prism whose surfaces form the 90° angle reflecting the light beam through a total angle of 180°. The...

In optics, degreasers or ultrasonic arrangements used for removing pitch, cement or polishing material from lenses during...

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

A vacuum deposition method in which the coating material (target) is removed from the surface of the coating source...

Instantaneous field of view (iFOV) is a term commonly used in the context of remote sensing, imaging systems, and optical...

A material's ability to undergo plastic deformation, specifically elongation, without fracturing.

The method of determining the energy distribution of high-speed charged particles by the luminous effect formed when the...

Frame rate refers to the frequency at which consecutive images, or frames, are displayed in a video sequence. It is...

A fixed-focus camera designed to record the ink impression of fingerprints that have been impressed on a card or form for...

A microscope in which laser light is delivered through single-mode fibers that replace the pinhole usually used in confocal...

Electric polarization characterized by homogeneous polar dielectrics and ascribed to the position of the permanent molecular...

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

The average length in a specific material in which a relativistic charged particle will lose 67 percent of its energy by...

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

Metamerism that occurs when the geometry of illumination or viewing is changed.

Electromagnetic energy that is capable of producing photochemical activity.

The process of reducing the size of an image by removing a certain proportion of the samples produced from the original...

A grazing incidence mirror telescope with concentric conic surfaces having a single common point: a paraboloid-hyperboloid...

An instrument designed to measure radiation indirectly through the use of several phosphors and a photomultiplier tube. The...

A solid-state device similar to an ordinary transistor except that incident light on the PN junctions regulates the response...

The ability of an electrical current to destroy superconductivity by means of the magnetic field generated by the current....

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

The use of computer systems for monitoring and controlling industrial production.

The process of transferring collected energy from solar radiation into a heat-absorbing medium (e.g., an insulated tank of...

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

The photographic recording of a visible image formed by the impact of invisible radiation on a fluorescent screen.

The spatial distribution of incident and collected flux contained in the analysis of reflectance, transmittance or densities.

A parabolic, elliptical, hyperbolic or circular section created when a solid cone is intersected by a plane.

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

A device used to alter the shape of or energy distribution within a beam of radiation.

A formula indicating that, for an imaging lens system, the image brightness for off-axis points will fall off at a rate...

A microscope eyepiece designed for use with apochromatic objectives. Since apochromatic objectives are undercorrected for...

Plasmonics is a field of science and technology that focuses on the interaction between electromagnetic radiation and free...

A form of liquid crystal in which flow does not take place in the usual manner. When examined with polarized light, the...

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

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

Radioactivity formed by the bombardment of stable elements by either neutrons or high-energy, charged particles under...

A spectrophotometer having a prism or, more frequently, a grating for the study and recording of infrared spectra. It...

An instrumental technique that utilizes the mass-to-charge ratio of charged particles as recorded from a mass spectrometer...

The measurement of surface temperature by a thermograph that forms a pattern of the heat radiated by the surface on a...

An autocollimator is an optical instrument used for measuring small angular deviations with high precision. It operates on...

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

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

The liquid used in microscopy to fill the space between the high-power objective lens and the microscope slide in order to...

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

In television, a lateral displacement of the lines from their normal position due to the instability of a synchronizing...

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

The simultaneous occurrence of direct and diffuse transmission.

White, tetragonal crystals used in the production of luminous coatings.

A prism produced by severing a Nicol prism and reconstructing the polarization angles of the two halves so that they are...

The region of the cathode-ray tube phosphor screen restricted by the tube and instrument specification.

A film applied to a coated or uncoated optical surface primarily for protecting this surface from mechanical abrasion, from...

An Abbe condenser in which the upper lens element is fixed. The lower lens may focus the illumination between the elements...

The radiation emitted from a group of charged particles that does not depend on the temperature of the source in which those...

The diffraction of a particle by a standing lightwave.

Return of radiation by a surface, without change in wavelength. The reflection may be specular, from a smooth surface;...

Also called Geiger-Müller counter. An instrument designed to detect and measure radioactivity through the use of a...

Laser-powered telephone device for analog communications that employs a vibrating plastic membrane as a transmitter to...

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

Equipment used for chemical analysis by investigation of the spectra formed and observed in chemical activity. Of particular...

An amplifying device that returns a portion of its output to its input as a means of modifying the device's performance.

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

The loss of optical power in an optical fiber because radiation escapes through its bends. The radiation loss caused by...

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

A Laurent polarimeter is an instrument used in optics for measuring the rotation of plane-polarized light caused by...

The determination of the relative phase shift of an image as a function of frequency. A phase change of 180° with...

Technique in which the polarization rotation of light, and its relationship to the magnetic field strength can be analyzed...

Radiation used to excite an optical or laser material to a higher energy level. See optical pumping.

The ejecting of ions from the surface of a material.

Abbreviated PAI. An imaging modality with a hybrid technique based on the acoustic detection of optical absorption from...

The formation of an interferogram by means of two holograms on the same recording medium, often used for determining small...

The laser pumping that exhibits an advantage over longitudinal pumping in that the threshold pump power density can be...

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

When applied to LCD grids, the active matrix is a means of supplying power to pixels by use of a transistor and capacitor....

Virtual histology refers to the use of digital technology and computational methods to simulate or recreate histological...

A birefringent crystal having two axes along which there is an absence of double refraction. Mica, sulphur and turquoise are...

The law stating that when light strikes a surface at such an angle that the reflected and refracted rays are perpendicular...

A modulator is a device or component that modifies a carrier signal in order to encode information for transmission over a...

The term reflective is an adjective that describes the ability of a surface or material to reflect light or other forms of...

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

Data or encoded information capable of being eradicated, leaving the media free for rewriting. Also called reversible.

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

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

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual...

An enzyme-linked immunosorbent assay (ELISA) is a laboratory technique used to detect and measure the presence of specific...

A phase-shift interferometer used to detect the relative angular speeds or positions of two concentric rotors.

A device that detects and measures the quantity of exposure to nuclear radiation. It uses a special glass rod that...

Gas detection measurement technique that uses a built-in capacitative microphone to calculate the amount of absorbed laser...

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

The formula that indicates the total radiation at all wavelengths from a perfect blackbody. W Total = 5.67 x 10-12 T 4(W/cm2)

A controlled random search process, such as generalized simulated annealing, that has been incorporated into many optical...

An astronomical scanning technique for capturing images of stars without moving the sensor. To perform a drift scan, a CCD...

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

The freeing of electrons from a filament in an electron tube as the result of the filament being heated by an electric...

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

A type of eyepiece, or the modification of an eyepiece, in which a small hole, without a lens, functions as the eye lens;...

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

In semiconductor physics, the term bandgap refers to the energy range in a material where no electronic states are allowed....

A device having electrical resistance and used in an electric current for purposes of protection, operation or control of...

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

A compact optical projection system, mounted on or built into a helmet, and used to project data or a scene directly into...

In optics, the mechanical tension, compression or shear in optical glass due to internal stress caused by improper cooling...

In image processing, a morphology operator in which a structuring element or probe of a particular shape is moved over the...

Optical fibers fused together to form a solid, vacuum-tight assembly in the form of a slab or rod. Discs or rectangular...

Commonly performed in spectroscopy, the optical null process is a method for radiation detection whereby physical detectors...

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

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.

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

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

Camera Link HS (high speed) is a standard developed for high-speed digital data transmission in machine vision and...

A short term for latent image intensification, a process much like hypersensitizing in photography, but used after exposure...

The amount of energy required to raise the energy level of an atom; a necessity if the atom is to radiate energy. High...

A junction between semiconductors that differ in their doping level conductivities but not in their atomic or alloy...

The lowest frequency at which the magnitude of the fiber transfer function decreases to a specified fraction of the zero...

Technique that defocuses activity from surrounding planes by means of the relative motions at the point of interest.

Optoacoustic, or photoacoustic, refers to a phenomenon and related techniques that involve the generation of acoustic waves...

The production and analysis of spectra with the use of a spectrograph.

An assembly of optical fibers that will not transmit coherent images or information because the relationship of the fibers...

The scanning of a region in a given sequence of slender, straight parallel strips.

The imaginary line passing through both the centers of curvatures of the optical surfaces of a lens or mirror; the optical...

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

A method for obtaining the optical absorption spectra of solids, semisolids, liquids and gases. PAS is inherently...

A graphic representation of a distribution function such as frequency by means of rectangles whose widths represent the...

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...

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

A prism having several plane polished surfaces, some to transmit light, some to reflect light, and some to serve both...

A characterization of the throughput performance of data storage systems; the EDR is the total of data retrieved divided by...

With respect to a lens, the reciprocal of its focal length. The term power, as applied to a telescope or microscope, often...

Recombinase polymerase amplification (RPA) is a molecular biology technique used to rapidly amplify specific DNA or RNA...

For a laser, the maximum exposure time that the laser design allows; 0.25 seconds for a Class 2 laser.

A densitometer having a receiver that indicates when a desired radiation level has been attained.

A precision-engineered microminiature light source that is safe for darkroom use, yet emits a beam of light bright enough to...

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

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

The optical reconstruction of image information contained in a sound field. First the diffraction pattern, formed by an...

The organ of vision or light sensitivity.

The formation of a block by attaching optical elements to a plate with a ring of pitch or other thermoplastic material.

I/O stands for input/output. In computing, it refers to the communication between a computer system or program and its...

A medical imaging method in which gamma camera heads rotate about the patient to detect radionuclides, enabling physicians...

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

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

The digitization process by which an image is manipulated to increase the amount of information perceivable by the human eye.

Light produced by visible radiation that moves from the light source to the object without reflection. With respect to...

The perception of depth due to binocular vision.

With respect to atomic fluorescence spectroscopy, the fluorescence that is emitted by an atom at a spectral line of a...

A photocathode that exhibits maximum sensitivity in the blue and ultraviolet regions of the spectrum. The sensitivity is...

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

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

Nd:YAG laser refers to a solid-state laser that utilizes neodymium-doped yttrium aluminum garnet (Nd:Y3Al5O12) as the gain...

A beamsplitting mirror that reflects as a function of wavelength.

The fraction of incident light power in an optical modulator that is available to the output beam.

A GRIN (gradient index) lens is a type of optical lens that utilizes a gradient in refractive index across its volume rather...

The specular reflection of individual parts of a surface.

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

A device that permits the adjustment of facsimile transmitters and recorders so that their scanning lines stop and start at...

See inverted image; population inversion.

An accelerator at the Argonne National Laboratory, providing powerful x-ray beams for materials research applications.

Virtual reality (VR) is a computer-generated simulation of a three-dimensional environment or experience that can be...

The level of the television picture signal that corresponds to the maximum limit of black peaks.

A quantitative measurement of the coherence of a light source; equal to the visibility (V) of the fringes of a two-beam...

A photosensitizing drug used in conjunction with photodynamic therapy.

With respect to microscopy, light that is directed through the specimen by a substage condenser.

An eyepiece having a special prism arrangement linked to a micrometer screw to allow reading of the angular relations...

The transfer of energy lost by radiation to the body, relative to the loss of energy per unit of path traveled.

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

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

Sputtering equipment is machinery used in the process of physical vapor deposition (PVD), specifically sputtering....

A process, either naturally occurring or mechanically induced, whereby water is changed from its liquid state into a vapor.

The dispersion of a light ray striking the surface of a biaxial crystal, in which the resulting rays are reflected in a...

A method of producing x-ray exposures as short as 0.03 µs; the primary application is in ballistic radiography.

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

The technique of producing spectrograms in wavelengths beyond 120 nm by the use of a diffraction grating and a Schumann...

The effect discovered by Faraday in 1845 whereby nonoptically active materials or substances become capable of rotating the...

Also known as single plane illumination microscopy (SPIM), this process was designed for imaging of sensitive samples and...

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

A lens consisting of two or more elements, usually of crown and flint glass, that has been corrected for chromatic...

Long-wave infrared (LWIR) refers to a specific range of the infrared spectrum. Infrared radiation is divided into three main...

3D printing, also known as additive manufacturing (AM), is a manufacturing process that builds three-dimensional objects...

In colorimetry, the phenomenon in which spectrally different radiations produce the same color sensation for a given...

In data communications, the instrumentation connecting two stations: transmitters, receivers and the cable that runs between...

1. The variation in intensity of a light beam as it travels through the atmosphere. 2. In radiation physics, a light flash...

A method of analysis in which a pulsed laser beam is used to heat a particle, producing a plasma, or laser spark. As the...

Incapable of being penetrated by any form of radiation.

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

The re-emission of absorbed energy, having the same wavelength as the incident energy, in an arbitrary direction from a...

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

Surface-enhanced Raman scattering (SERS) is a powerful analytical technique that enhances the Raman scattering signal of...

The parallel resistance and capacitance appearing between the active guard ring junctions in a silicon photodiode.

Equipment for testing an observer's color vision. Some tests require the identification or ordering of colored samples. The...

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

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

The emission and/or propagation of energy through space or through a medium in the form of either waves or corpuscular...

High-voltage, fast-discharge circuit named after its inventor, Erwin Marx. Its capacitors are charged in parallel and...

The collection and analysis of data relevant to monitoring the rate and quality of industrial production, either...

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

A small round mirror on the end of a handle used for viewing inside an inaccessible cavity.

Sets of paired lines carefully designed to give the most accurate pointing possible for various lengths of sight.

A system of optical components designed to increase the diameter of a radiation beam. Usually an afocal system.

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

A fast-action shutter inserted between one end of a laser rod and the end mirror; when inserted to prevent emission and then...

A sputtering target is a solid material used in the process of physical vapor deposition (PVD), specifically sputtering....

A noncrystalline, inorganic mixture of various metallic oxides fused by heating with glassifiers such as silica, or boric or...

A cryogenic cooler device that is an intermittent Joule-Thomson refrigerator with a passive radiator serving as the...

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

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

A device that utilizes avalanche multiplication of photocurrent by means of hole-electrons created by absorbed photons. When...

Corrected for distortion.

Histology is the branch of biology and medicine that involves the study of the microscopic structure of tissues and organs...

Glass containing small quantities of neodymium oxide that is used as a filter plate in color television or as a lasing...

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

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

The longest wavelengths of the ultraviolet region, nominally 300 to 400 nm.

A liquid crystal light valve (LCLV), also known as a spatial light modulator (SLM), is an optical device that modulates the...

An instrument that uses a blackened silver-disc reflector with a shutter to create temperature fluctuations that are...

A special form of microscope that utilizes interference for observing and measuring the phase and optical thickness in...

A lens aberration that results in the tangential and sagittal image planes being separated axially.

A method of producing high-quality plastic optics in large volumes by injecting the heated, liquified plastic at high...

A write-once optical disc storage system in which the optical head reads continuously while writing to check the accuracy of...

A polishing material that has a quicker polishing action than rouge (ferric oxide) and that is cleaner to handle.

A 3D profile sensor, also known as a 3D profiling sensor or 3D depth sensor, is a technology that is used to capture and...

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

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

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

A method of scanning in which a frame transfer device produces a continuous video image of a moving object by means of a...

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

A modified form of an image-retaining panel that can be used in subdued daylight. This is achieved by adding a layer of zinc...

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

That element of a spectrum line in scattered radiation having a frequency equal to that of the corresponding incident...

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

The particular orientation of the image, such as normal, canted, inverted or reverted.

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

A process used to detect minute gravitational fields and to display images from objects by means of radiated gravitational...

Any pyrheliometer that has a filter placed over its sensor to limit the range of solar radiation it will detect; used to...

An interferometric method for describing the surface shape of large coated or uncoated optical flats. The procedure uses a...

The pulse-to-pulse fluctuations in power distribution among modes of a Fabry-Perot laser, which can result in...

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

An optical combiner, in the context of optics and display technologies, refers to a device or component that combines...

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

A light ray that has had its direction altered because of its traversing an air-to-glass interface at some angle. In an...

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

Schott Glass Technologies' trade name for a glass-ceramic material with a very low coefficient of thermal expansion.

An arc flash is a sudden release of electrical energy due to an electric arc — a continuous, high-current discharge of...

A flat cylindrical device generally used to polish terminated ends in fiber optic connections.

Broadening of a laser's spectral linewidth when the resonance frequencies of the atoms (or molecules) of the medium are not...

Conventional coordinates for optical system analysis, the X-axis being the horizontal, the Y-axis the vertical and the...

The three-dimensional interference pattern of fringes that is recorded on a holographic plate to facilitate the study of a...

In computer graphics, the coordinated two-dimensional or three-dimensional area of increased resolution where graphics...

A holographic grating is a type of diffraction grating that is produced using holographic recording techniques. It consists...

Describing the standard television method of raster scanning in which the image is the product of two fields, each of which...

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

The recording of patterns by the production and use of latent electrostatic charge patterns. See electrostatic process.

The process of microphotography that involves the reduction of the original at a ratio greater than 100 to 1. The process is...

Also known as a shadow mask, a perforated plate placed between the focusing and accelerating electrodes, and the tricolor...

A zone plate produced by a computer and having a binary structure that can be etched into a chromium or quartz layer. It...

A photonic integrated circuit (PIC) is a compact and integrated device that incorporates multiple photonic components and...

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

The intensity of radiation transmitted to a receiver.

A single number, defined by the computer program or the user that expresses the performance of an optical system. Also known...

A high-frequency approach to the propagation of light in graded-index fibers in which the modal field is represented in...

A device used to scan images or information on photographic film for the subsequent relay of information.

Design and engineering consulting services refer to professional services provided by specialized firms or individuals to...

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

An optical experiment carried out conclusively in 1887 that demonstrated that the ether, a hypothetical medium postulated by...

A means of illumination from which the infrared component has been removed by absorption or reflection filters within the...

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

The law stating that the illuminance (or irradiance) from a point source varies as the inverse square of the distance...

Infrared (IR) refers to the region of the electromagnetic spectrum with wavelengths longer than those of visible light, but...

A geometric representation of a light path through an optical device; a line normal to the wavefront indicating the...

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

Optical glass containing zirconium fluoride that results in special characteristics such as improved transmission.

The term half bandwidth (HBW) generally refers to the width of a spectral band or frequency range at half of its maximum...

A glass that is heated, then chilled (usually by an air blast) to set up internal stresses so that the surfaces are under...

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

A light-harvesting protein found in the purple membrane of a micro-organism called Halobacterium halobium. The protein...

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

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

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

More efficient than the Foucault knife-edge test, this test examines curved mirrors by using a transmission grating with 40...

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

Diamond turning refers to a precision machining process used to produce complex optical components, particularly lenses and...

The chromatic resolving power of a prism is invariably stated for the case in which parallel rays of light are incident on...

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

An optical lens manufactured to control the transmission of light over a specified wavelength range. Low absorption lenses...

The energy passed on as electromagnetic radiation; e.g., radio, heat or light waves.

Information presented as a continuously variable relationship between a signal and a standard.

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

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

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

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

The solid angle of a detector or system pupil as seen by the source.

A technique used to create a series of interrelated holographic images that give an appearance of motion when projected in...

Attenuated total reflectance (ATR) spectroscopy is a technique used in analytical chemistry to obtain IR spectra of samples....

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

A hologram in which diffraction is produced by the silver image, resulting in a dimmer image than in a phase hologram, where...

An absorbing coating medium between fibers, used in some fused fiber optic plates to absorb unwanted light. Such coatings...

Nanophotonics is a branch of science and technology that explores the behavior of light on the nanometer scale, typically at...

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

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

Fluid used to aid in examination of semifinished blanks.

Technique of projecting an illuminated target at infinity and receiving the target image after reflection from a flat mirror...

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

Phase contrast microscopy is an optical microscopy technique that enhances the contrast of transparent and colorless...

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

A Dammann grating is a type of diffractive optical element (DOE) used to create an array of equally spaced,...

A caustic formed by refraction.

A formulaic description of the linear change of the reciprocal optical dielectric tensor with either stress or strain.

A transmission line having no wave reflection along its path.

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

A femtosecond laser is a type of laser that emits ultrashort pulses of light with durations on the order of femtoseconds,...

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

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

Magneto-optics refers to the study and manipulation of the interaction between magnetic fields and light (electromagnetic...

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

Filoviruses are a family of viruses that are responsible for severe and often fatal hemorrhagic fevers in humans and...

A system of beacons used in navigation.

1. With respect to angular subtense, a source of light, such as a star, that is very small. In a lab, a point source may be...

In the SI system, prefix meaning one-millionth, 10-6. Abbreviated µ.

Triggering a laser at a predetermined time by pumping it to a level just below its threshold and then using an auxiliary...

Spectral domain optical coherence tomography is an imaging technique used in medical diagnostics, particularly in...

A high-speed shutter, similar to a Kerr cell, that uses the birefringence produced in a liquid during the passage of an...

A support device in which a column or chamber of air permits the free travel of a mobile part. In optical mounting and...

A photoconductive cell having greatest sensitivity in the infrared region. The photosensitive material of the cell is lead...

Scientific complementary metal-oxide semiconductor (sCMOS) refers to a type of image sensor technology specifically designed...

A standard for fiber optic telecommunications interfaces, with a 1300-nm data link operating over single-mode fiber at data...

The use of retroreflective projection technology (RPT) to project a background image onto a masked object, such as a vehicle...

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

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

For a Fabry-Perot interferometer or etalon, a value for the transmission bandwidth which can be calculated as the ratio of...

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

The bending of oblique incident rays as they pass from a medium having one refractive index into a medium with a different...

In fiber optic cable, containment of the fiber or fibers within an outer protective tube in which they can move to some...

Augmented reality (AR) is a technology that integrates digital information, typically in the form of computer-generated...

1. In visual perception, the minimum value of stimulus that can be perceived on the average. 2. In optical detection...

An optical device capable of transforming unpolarized or natural light into polarized light, usually by selective...

An amplifying device with a wide tuning range in which an electron gun sends a beam of electrons into a slow-wave structure....

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

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

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

A monochromator is an optical instrument used to isolate and select a narrow range of wavelengths from a broader spectrum of...

A tool used in cutting circular holes around a center. Also, a laser cutter in which the beam moves in relation to the cut...

An optical fiber's absorption of electromagnetic waves due to hydroxyl ions remaining after contact with water.

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

A fiber optic transmission system in which data can go in only a single direction.

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

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

Germanium crystal refers to a crystalline form of the element germanium (Ge), which is a metalloid and semiconductor...

Device in which contact ionization of atomic particles and thermionic electron emission are used to produce magnetically...

An acronym of gamma ray amplification by stimulated emission of radiation. It is a gamma ray laser that operates between...

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

The collection and detection of x-rays by virtue of their ionizing properties. The ionization may be perceived directly by a...

A series of high contrast block letters or similar objects arranged to permit the evaluation of eyesight in humans.

Cinematography performed with the use of a microscope to film the actions of microscopic specimens.

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

Process that occurs when a polymerized soft plastic rod with higher refractive index is placed in a bath of a lower...

Free-space optics (FSO), also known as optical wireless communication or optical wireless networking, refers to the...

A grating that serves to provide higher resolution and dispersion than the average grating, and still has a greater free...

A light-interference device whose excitation is determined by the modulation of a light beam by an ultrasonic field.

A lens designed for projection of color transparencies.

Distortion of the high frequencies of a signal. In television, the term generally applies to frequencies above the 15.7 kHz...

Medical diagnostic (x-ray) imaging using laser printers to produce high-resolution digital hard copy instead of film exposed...

A system of modular mechanical components for building precision optical systems. The basic equipment includes a variety of...

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

An established point on which the observer's eye is focused.

Fluorescence lifetime refers to the average time it takes for a fluorophore, a molecule that absorbs light at one wavelength...

A device having a pair of decentered lenses, one for each eye, that focuses on a single object as a magnifier. It is often...

A process by which a plastic cell is molded around a glass lens or lenses to create a mount, eliminating the metal barrel...

A projection printer that is capable of reproducing a multiplicity of images from a master transparency on a single support...

Also known as an optical diode, an optical isolator is a device that utilizes the Faraday effect to suppress or redirect...

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

Film designed especially for the needs and conditions encountered in aerial photography. It is produced in a variety of...

A recorder that plots, on a chart, the interaction between two variables, not directly representing time.

The property exhibited by certain birefringent crystals in which the degree with which they transmit polarized light is...

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

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

Also known as ground level. The lowest energy level of an atom or atomic system. A material in the ground state is not...

A zone plate in which the zones are alternately transparent and opaque to specific radiation, and coarse enough so that no...

A matrix-controlled display that has information storage at the display surface, and requires that an element be addressed...

The ratio of the intensities of two specified spectral lines of a source having vastly different excitation energies. This...

The scientific observation of celestial radiation that has reached the vicinity of Earth, and the interpretation of these...

See regular transmittance; the term specular is not properly applied to transmission.

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

Any lens with at least two lens elements, each of which can be used singly or in combined configurations.

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor...

The theoretical explanation and analysis of the interactions between electron waves and crystals used in studying electron...

An ultrafast pulsed laser is a type of laser that emits extremely short pulses of light with durations typically on the...

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

A furnace used to heat glass materials. It may be a small laboratory-type furnace for small-scale experiments or large...

A special-purpose polarimeter having a scale calibrated directly in the concentration of sugar in the test solution.

The total range of wavelengths, extending from the shortest to the longest wavelength or conversely, that can be generated...

A device in which slab geometry internally compensates for thermal-optic distortion; the solid host material -- glass or...

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

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

A technique of using dyes during endoscopy to improve tissue differentiation. Dyes such as methylene blue, Toluidine blue...

Spectroscopy used to study the concentration, diffusion and Brownian motion of small particles suspended in a fluid by...

In ophthalmic practice, an instrument that determines the boundaries of the field of view. It is composed of a 2-m square of...

A hologram formed without lenses and with the object and reference points sharing the same plane. In the initial recording,...

A filter possessing one transmission band that extends from a cutoff frequency other than zero to frequency at infinity.

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

Directing an optical beam in varying directions by varying reflection, refraction, focusing and diffraction methods.

A method of resampling in which a 16-pixel neighborhood around a given pixel from the original image is used to calculate...

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

A type of video signal in which the luminance and chrominance portions of the signal, or the luma and chroma, have been...

The total fusion and sealing of materials, or usually an enclosure, to ensure that they are airtight.

A hologram produced by a pair of radiation beams, each carrying information.

A hologram that is illuminated by a source opposite the viewer.

The region of the electromagnetic spectrum from 320 to 400 nm.

A natural or mechanical system adversely affected by the influence of laser radiation. During laser damage the common effect...

Method of preserving the measured color value and color information as it is translated from differing devices. For example...

Array used in coded-aperture imaging experiments with two-beam CO2 lasers that provide an artifact-free process, faithful...

Aspect of vision permitting the observer to distinguish among stimuli by their hue, saturation, and brightness or lightness.

Instrument that uses absorption spectroscopy to detect gases in planetary atmospheres. Dispersed incoming radiation is...

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

The length of optical waveguide needed to attain equilibrium mode distribution for a specified excitation condition.

In the SI system, prefix meaning 1 million, 106.

A laser fitted with up to eight optical fibers that transmit the energy to different workstations in turn.

Any of several compounds capable of binding heavy-metal ions, thereby preventing interaction between the bound ions and the...

A 2-million W, 2.7-µm-wavelength hydrogen-fluoride laser used as a directed energy weapon.

A grating beamsplitter is an optical device that utilizes the principles of diffraction to split a beam of light into...

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

The attribute of visual experience that can be described as having quantitatively specifiable dimensions of hue, saturation,...

Also known as transverse mode. The configurations of energy storage, relative to the structure of a laser resonator, that...

A broken circle used as the test object in distinguishing visual acuity. The width of the gap in the circle is equal to the...

The combination of more than one type of small-molecule monomer into a polymer.

A short focal length (less than five inches) positive lens used to produce a magnified image of the object being viewed....

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

The point of intersection of the optical axis with any centered optical surface.

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

A device that measures the intensity of photochemically active radiation, particularly from the sun. One form of this...

A thermal source that emits less radiation than a blackbody under identical temperature conditions.

A small television monitor that replaces the reflex viewfinder in a television camera.

With reference to electromagnetic radiation, the number of crests of waves that pass a fixed point in a given unit of time,...

The wavelength or frequency corresponding to an absorption resonance with a given molecular or atomic species. The line...

Formulas designating the relationships between image distance, object distance, focal length, refractive index, etc., of a...

1. To influence to a single direction. 2. Voltage that is applied to a solid-state device.

The altering of lightwaves by acoustic waves in a solid medium.

A range of wavelengths within which radiation transmitted through the atmosphere suffers relatively little absorption by...

Graphic representation of quantified values of image quality whose points all refer to images that are of a constant...

Voltage that produces current flow in the direction of lesser resistance to the steady-state direct current, i.e., from the...

A method of graphical ray tracing through a boundary surface dividing two media of differing indices of refraction.

Gram-positive bacteria are a group of bacteria that have a thick cell wall composed primarily of a substance called...

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

A flanged or plain ring with a restricted aperture, located in an optical system at any of several points, that cuts off...

An optical scanning device designed to read information printed in the form of bars of different size by detection and...

The state of optically excited luminescence. Luminescence refers to the light emitted by excited atoms or ions as they decay...

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

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

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

Quantum efficiency (QE) is a measure of the effectiveness with which a device or system, typically in the context of...

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

The term light field refers to the spatial distribution of light rays traveling in all directions through a given space. It...

Unlike the thermocouple or bolometer, the pyroelectric infrared detector is a current source with an output proportional to...

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

A technique for observing the decay of light emissions from sources following their pulsed excitations, based on recording...

An energy transition concerned with the combination of a photon and a phonon.

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

A quantum dot is a nanoscale semiconductor structure, typically composed of materials like cadmium selenide or indium...

An electronic device consisting of a semiconductor material, generally germanium or silicon, and used for rectification,...

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...

The alteration of electric conductivity produced by the absorption of varying amounts of radiation composed of photons.

The emission of radiant energy in which the energy emitted originates in the thermal motion of the atoms or molecules of the...

Any arrangement of a bundle of optical fibers that alters the shape of the image. For example, by systematic regulation of...

The fusion frequency of flicker that is needed just to produce complete fusion and to assure the visual sensation of...

Near-infrared spectroscopy (NIRS) is a non-invasive analytical technique that uses the near-infrared region of the...

In image acquisition (and sampling theory), the postulate that the pickup sampling frequency must be a minimum of twice as...

Radiation emitted from vibrating charged particles. A combination of oscillating electrical and magnetic fields that...

Contraction of "picture element." See pixel.

A mirror whose coating serves to reflect visible radiation while transmitting the infrared.

The combination of two or more different small-molecule monomers into a polymer.

A digital twin refers to a virtual representation or digital counterpart of a physical object, system, or process. This...

With respect to waveguides, the continuous change in the direction of the axis of the wavelength, during which the axis is...

Observed phenomenon in laser pulses in which a large number of excited electrons are created and in which multiphoton...

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

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

A fiber Bragg grating (FBG) is a type of optical filter that is inscribed or "written" into the core of an optical fiber. It...

A resampling and interpolation method that uses only the value of the nearest neighbor pixel, while not considering values...

STED microscopy, or stimulated emission depletion microscopy, is a superresolution imaging technique in fluorescence...

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

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

A mode of data transmission whereby bits of information are carried simultaneously at different frequencies over a single...

Laser sintering is an additive manufacturing (AM) or 3D printing technology that involves using a laser to selectively fuse...

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

Any of a number of instruments that uses a flame to vaporize a solution of the chemical being analyzed so that light may be...

A pump-probe technique whereby a single wavelength source may be used in order to excite a given sample to determine...

An extremely powerful microscope that renders individual ionized atoms visible by using an electric field to propel the ions...

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

The first-order spectrum formed by a diffraction grating.

In laser damage testing, the exposure of many sites of a sample to different intensities of laser irradiation to discover...

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

The basis of color vision in the human eye. Three types of cones have been identified, each having a unique spectral...

A type of transversely excited laser with a uniform arc-free discharge of large cross-sectional area that can be scaled to...

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

The determination of what, how much and in what proportions chemicals must be combined to produce the desired reactions and...

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

A near-infrared (NIR) spectrometer is an analytical instrument used to measure the absorption, transmission, or reflection...

The rotation of an instrument (or the line of sight of an optical system) in a horizontal plane; transverse.

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

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

A telescopic light-sensing meter used to measure illumination levels of small regions at a distance of many feet; it is used...

The law stating that the brightness of an object that is examined through a slotted disc, rotating over a critical...

A detector cooling device in which a gas under high pressure escapes through an expansion valve in the tank; as the escaped...

That invisible region of the spectrum just beyond the violet end of the visible region. Wavelengths range from 1 to 400 nm.

Fiber optic cable bearing many fibers independently sheathed and capable of carrying unrelated signals. They often surround...

The length of the oscillation of a grinding or polishing lap.

A heterochromatic photometric process using successive comparison of similar chromaticities and the calculation of relative...

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

The positive ion current created in an electron tube as a result of the collisions between electrons and residual gas...

Liquid marble refers to a unique form of microscale liquid encapsulation, where small droplets of liquid are coated with a...

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating...

Photoimmunotherapy (PIT) is a medical treatment approach that combines elements of phototherapy and immunotherapy to target...

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

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

A device designed to measure linear or rotary motion by detection of the movement of markings on a transparent medium past a...

An LED, or light emitting diode, is a semiconductor device that emits light when an electric current passes through it. LEDs...

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

Plastic optics refers to optical components or systems that are made from transparent plastic materials, as opposed to...

A phonon is a quantum of vibrational energy associated with the periodic motion of atoms or molecules in a crystalline...

A tachometer consisting of a light source, rotating perforated wheel and phototransistor to measure the rates of rotation of...

Wavelengths between 400 and 1400 nm (VIS to NIR) are focused onto the retina by the cornea. Because the retina is sensitive...

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

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

The relationship between different wavelengths of light generated by a source, which may affect the spectral distribution of...

The limitation on performance imposed by the distortion of a received signal rather than its amplitude or power.

A series of permanent holograms in dichromated gelatin formed by opening total page-composer apertures and setting a point...

A device that uses low-level visible radiation or infrared radiation to produce a visual image of a night scene. These...

In image processing, a specially designed programmable computer peripheral that attaches to the host system for the purpose...

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

A vision defect commonly referred to as farsightedness. Results when the image of a distant object is focused beyond the...

The minimum value of luminance for vision. The value may vary with age as well as dark adaption period. (Measured range...

Any irregular motion, variation in intensity or change in color that arises because of atmospheric turbulence during the...

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

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

Noise created by patterns imaged on a CCD surface. Pixel sensitivity is altered by responsivity during illumination.

In a solid-state laser, the material (Nd:YAG, Nd:glass, ruby) in which lasing action takes place.

A photomask, also known simply as a mask or reticle, is a key component in the photolithography process used in...

In chemistry, a device in which a chemical reaction takes place. In electronics, a device that introduces reactance into a...

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

A Kerr soliton refers to a specific type of soliton, a self-reinforcing wave packet, that arises in nonlinear optical...

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

Pertaining to electromagnetic radiation as perceived by the eye; that is, with the contributions as wavelengths in the...

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

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

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

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

Behaving as though characterized by a series of waves having planes of vibration oriented at all possible azimuths.

The optically pumped, solid-state laser that uses sapphire as the host lattice and chromium as the active ion. The emission...

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

The use of mathematical analysis to derive solutions in the science of photogrammetry.

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

The chromatography method in which the stationary phase is supported in or on an inert packing in a column, through which...

Optical glass refers to a type of glass specifically engineered and manufactured for use in optical components and systems,...

In the context of materials science and semiconductor physics, doping refers to the intentional introduction of impurities...

A compound lens consisting of two negative lenses of flint glass. A double-convex lens of crown glass is cemented between...

A system of sensors and related instrumentation that allows a navigable object (usually a missile) to locate its destination...

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

Frequently used in astronomical measurement, it is based on the diurnal rotation of a star relative to the fixed stellar...

A feature of some imaging devices, such as digital cameras, that allows them to compensate for different lighting conditions...

Magnification that is above the level of maximum useful magnification and does not contribute useful resolving power. In a...

A lensless photographic camera that uses a small sharp-edged hole as its aperture. The light passed by this aperture onto...

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

An electron-gun system is an assembly used to generate and control a focused beam of electrons. Electron guns find...

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

Ferroelectric materials are a type of dielectric materials that exhibit spontaneous electric polarization, meaning they...

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

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

1. The additive process whereby the amplitudes of two or more overlapping waves are systematically attenuated and...

Enhanced picture archiving and communication system (PACS) display (ePAD) is a software tool used in medical imaging to...

In passive optical components, loss that varies as the polarization state of the propagating wave changes. Expressed as the...

In positioning, in-plane rotation about the vertical axis. Also known as azimuth.

In coherent optical communications systems, a laser used at the receiving end to produce a steady wave that is combined with...

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

The maximum angle of view that can be recorded by a camera. Field is a function of lens focal length and film format.

Lines of equal atmospheric attenuation in a laser beam.

A custom optic refers to an optical component that is designed, manufactured, and tailored to meet specific requirements or...

A method of demonstration or examination using a point source illumination without the use of any projection lens between...

A combination 80-column computer card containing a 35-mm microfilm frame. Reference data can be punched onto the card to...

RGB stands for red, green, blue, which are the primary colors of light used in additive color mixing. The RGB color model is...

Pixel binning, also known as pixel merging or pixel combining, is a technique used in digital imaging and camera technology....

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

Composed of one color; having only one wavelength of radiation.

See plane-polarized light; polarization.

The ratio of the intensity of the total radiation reflected from a surface to the total incident on that surface.

The radiation produced when a charged particle traverses a medium that has a refractive index considerably greater than...

A method of producing magnified images by x-rays. The specimen is placed close to a point source of x-rays; the...

Van der Waals forces refer to the attractive or repulsive forces between molecules (or parts of molecules) that arise from...

In the context of thin film deposition processes such as evaporation or sputtering, masks are used to selectively deposit...

A finite version of Shannon's sampling theorem that states that a class of functions can be reconstructed exactly by a...

That process by which radiation spontaneously emitted by a volume of optical materials is resonantly reabsorbed within the...

The condition of the numerical aperture or beam diameter of the laser, LED, or other optical source being larger than the...

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

Two electrodes that shift the electron beam vertically on a cathode-ray tube screen using electrostatic deflection.

An optical system that is corrected for distortion and spherical aberration and therefore forms the image of a straight line...

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 Ti:sapphire laser is a type of solid-state laser that utilizes a titanium-doped sapphire crystal as the gain medium. The...

A wave in which energy is focused near a boundary separating materials having different properties. Propagation of the wave...

A passive coupler that distributes signals from one or several inputs among a larger number of output waveguides arranged...

1. The ring patterns of light that seem to encircle particles in the field of a microscope. 2. See Newton's rings.

In optical character recognition systems, the identification of a character facilitated by means of known factors governing...

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

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures changes in hemoglobin...

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

The elimination of magnetic moments and decrease in magnetic susceptibility with a decrease in temperature due to the equal...

The detection and analysis of the relative response of a material to light over the range of wavelengths.

A device used in thin-film deposition; the material to be evaporated is placed in a crucible that is heated inductively by...

Ultrasonic refers to sound waves with frequencies higher than the upper audible limit of human hearing, typically above...

A mirror blank refers to the initial piece of material from which a mirror is made. It is typically a flat or slightly...

An array of refractive microlenses that are round, square and hexagonal and as small as 15 µm. They are used for...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical...

A CMOS image sensor, short for complementary metal-oxide-semiconductor image sensor, is a type of semiconductor device used...

The breakdown of the bonds in polymer chains caused by illumination.

A line of the Raman spectrum that fulfills Stokes' law because it possesses a wavelength that is greater than the radiation...

A compound lens combination whose astigmatic difference is zero for one or more off-axis zones in the image plane. In such a...

The approximate dimension of the refractive-index correlation length in a given medium.

An optical table, also known as an optical bench or an optical breadboard, is a specialized platform used in optics...

The resulting contraction or expansion of a piezoelectric crystal along an electric axis when the crystal is under the...

A single band in a group of light and dark bands that can be viewed in the periphery of Fresnel diffraction shadow.

A substance that increases a material's sensitivity to electromagnetic irradiation. In photodynamic therapy, a drug used to...

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

Equipment that supports microscopic live-cell imaging by managing the gas, media perfusion, temperature and other factors to...

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

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

Fluorescence lifetime imaging (FLIM) is an advanced imaging technique that provides information about the lifetime of...

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

In micropositioning systems, motion (most frequently undesired) about the Z-axis.

The wavelength at which a lamp radiates its highest intensity.

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

In digital data transmission, the separation of the two binary states into output at two frequencies.

An angstrom, symbolized by the Ångström or Å, is a unit of length used to express atomic and molecular...

A microcircuit whose passive components consist of a ceramic-metal combination deposited on a given substrate by screening...

The phenomenon observed by A.H. Compton in 1923 -- that some scattered radiation possesses a longer wavelength and...

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

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

The procedure applied to flame-excited line emissions to determine spectra and wavelengths.

A form of infrared CCD that utilizes internal photoemission as a photodetection mechanism.

In a semiconductor, the state created by the addition of a dopant that provides excess electrons.

A mass-relieving method whereby material is removed through the sides of a reflector in a direction parallel to the surface....

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

The energy analysis of electrons released in a secondary step following initial excitation or ionization.

The extreme case of self-absorption.

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing...

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

The application of a constant stress to an optical fiber.

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

The method of acquiring characteristic x-ray spectra from microscopic samples by use of the combination of a scanning...

In optical emission spectroscopy, the reduction in radiant power in the central portion of spectral lines arising from the...

A laser dye whose absorption coefficient drops at high levels of incident radiation. The phenomenon is often called...

In a CD-ROM disc, the reflective area between nonreflective pits representing a binary-language "off'' as opposed to...

A connection, typically made up of one or more cables, between a laser head and a separate power supply. Flexible pipes or...

1. Mounting a lens or mirror so that its optical axis is coincident with the optical or mechanical axes of other portions of...

The direct cladding used for fused silica cores to create large numerical aperture fibers and used as overcoats to...

With respect to a beam, the radiation lobe having the direction of maximum radiation.

The total optical power loss caused by the insertion of an optical component such as a connector, splice or coupler into a...

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

A Bose-Einstein condensate (BEC) is a state of matter that forms at temperatures close to absolute zero. It is named after...

The film used in photographic dosimetry to record the types and amounts of ionizing radiation, such as x-rays and gamma...

A contraction of binary digit; the fundamental unit of digital computing, a bit is either 1 or 0, expressing the binary...

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

Least value of color value combinations which gives white light; minimum purity as determined to be white.

The sensations of hue and saturation, taken together, but not brightness or lightness.

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

In fiber optics, a material whose properties, usually of transmission, are distinctly affected by the absorption of water...

A strip or annulus of glass coated with a semitransparent material such as inconel. The coating thickness, and as a result...

A diffraction pattern sampling unit composed of a 32-element monolithic silicon photodiode array and a readout unit. The...

That part of the cladding wherein the refractive index is constant within a specified tolerance, as a function of radius.

A broadband filter is an electronic or electromagnetic device designed to pass a range of frequencies or signals within a...

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

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

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

A lamp designed to emit a large amount of infrared radiation; used in applications requiring heat.

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

The value equal to the raster height divided by the half-period of a periodic test pattern.

The formation of a distinct, irregular surface pattern on a photographic emulsion due to differential swelling of the...

In optical character recognition, an intermediate step between character location and feature extraction.

An organizational method used in optical design computer programs. The technique produces one number (merit function) to...

A type of geometrical distortion that brings about a trapezoidal display of a nominally rectangular picture. Usually...

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

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

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

Proportions of standard primaries (tristimulus values) required for a color match; ratios of each tristimulus value of a...

A device used to accelerate the electrons in a free-electron laser by supplying electrical energy to the electron beam...

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

A phenomenon in which high optical power, encountering an imperfection in an optical fiber, destroys the fiber's core and...

The reproduction of a picture or image, produced by scanning the image and converting it into electrical signals that carry...

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

The photographic recording of objects or events in a manner that allows quantitative information to be derived from the...

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

A crystal of microscopic size having no definite plane faces and having a globular shape. At the time the crystal is formed,...

An infrared light source is a device that emits light in the infrared spectrum, which lies beyond the visible spectrum of...

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

1. A measure of absorbed dose, equal to the energy imparted by ionizing radiation to a mass of matter corresponding to 1 J...

Typically used for the examination of manufactured or engineered parts, an optical gauging device, in which a backlight is...

The light flash that occurs when an electrical field is applied to a phosphor already excited by ultraviolet radiation.

A system that satisfies the Abbe sine condition, and is free from spherical aberration and coma.

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

The process of grinding the toric surface of a single vision sphero-cylindrical lens.

The calculated normal distance from a photon source at which harmful interaction with the incident light will occur....

A fiber-coupled photoconductive antenna (FCPA) is a type of optoelectronic device that combines a photoconductive antenna...

1. A group of optical fibers that are fused and then treated to produce a vacuum-tight optical fiber cone or plate. 2. An...

A scintillation crystal, also known simply as a scintillator, is a material that emits light when it interacts with ionizing...

A type of laser welding that produces short-duration vapor pockets without buildup of heat in the part, useful for parts...

The generation of a difference in electric potential between two electrodes when radiation is incident on one of them.

A combination of a polarizer and an analyzer that is used to detect birefringence or rotation of the plane of polarization...

Simulation of radiative transfer in which each photon is generated by a source and its path through the medium is...

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

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a...

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

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

A still or motion-picture camera designed to photograph through a microscope. Photomicrographic equipment usually contains a...

Any bending of a wave of radiation away from its expected path, as, for example, by diffraction or by a magnetic field.

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

A Pockels cell in which electrical current is applied in a direction orthogonally to that of the light beam.

The action of a biological system responding to a single or multiple coherent particles of light produced from a laser...

The diffraction pattern of a source such as a light-emitting diode, injection laser diode or the output end of an optical...

An interferometer spectrometer designed to measure thicknesses of thin films or layers by recording the interferogram and by...

The end of an optical fiber farthest from the source of illumination.

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

The structure that holds the photographic negative in a proper position that is both flat and parallel to the lens plane, as...

Spots in a polished glass surface that are opaque and have a silvery, metallic reflection.

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

A microdensitometer that contains a scanning stage to provide simultaneous representations of position vs. density.

An instrument that contains a spectrograph with a grating in which an array of slits, in place of a photographic plate, is...

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

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 scattering of electromagnetic waves by free electrons, whereby the incident radiation and the scattered radiation are of...

The ability of a vision system to interpret an image in a short enough time to keep pace with most operations.

Irregular propagation of a wave due to variations in the medium's density or refractive index.

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

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

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

In imaging technology, assigning color to black and white images to differentiate features or convey information. Also...

A grating used as a reflectance filter, particularly in the far-infrared. Small plane gratings, blazed for the wavelength of...

The application of coating without heating of the substrates.

A reflecting surface that scatters radiation that is incident on it, thus producing diffuse reflection.

A measurement method for reflectance by gas ionization in which light passes through a vapor before and after reflection....

Time-correlated single photon counting (TCSPC) is a technique used in photon counting applications, particularly in the...

Best point of focus for an image in a beam of light at the smallest cross section of the beam.

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

The force that stimulates the emission of an electrical current when photovoltaic action creates a potential difference...

A transparent powdered solid immersed in a liquid or plastic of similar refractive index but widely different dispersion;...

A filter that transmits infrared and ultraviolet but is opaque to visible radiation.

The luminous trace formed on the cathode-ray tube screen by the motion of the electron beam.

A telescope with a concave paraboloidal objective mirror and a small plane (diagonal) mirror that reflects rays from the...

A medium that scatters or absorbs radiation that passes through it.

The spreading of potentially equal radiation frequencies that results in broadening of the spectral line. This effect is...

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

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

The production of visible light by infrared radiation whereby the light is produced by heat and not by any direct change in...

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

A technique for detecting free radicals by their electronic spectra. The material to be studied is placed in a...

A scanning laser radar system applied to transmission and concentration analysis in three dimensions of clouds as well as...

A contour mapping technique that uses electronic scanning and sampling techniques instead of a reference grating (see moire...

The error inherent in spectral energy or spectrophotometric quantity due to the finite dimension of the entrance and exit...

An interferometer that functions by first detecting the light striking each aperture and then combining the two detector...

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

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

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

In the discharge of a vacuum tube, the narrow, nonluminous region that sometimes may be found between the cathode and its...

The array of methods used in the transmission and reception of pictures and images with a three-dimensional appearance.

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

In an optical system, the gradual reduction of image illuminance as the off-axis angle increases, resulting from limitations...

With respect to a traveling plane wave at a known frequency, the space rate of decrease of phase of a field component in the...

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

The substrate upon which a diffraction grating will be ruled. It must be dimensionally stable, and the surface must be...

Effect whereby two electrons lose synchronism with the accelerating field and are lost during synchronous radiation. The...

Flux per unit solid angle and per unit area measured normal to the direction of propagation of the flux.

A splice accomplished by the application of localized heat sufficient to fuse or melt the ends of two lengths of optical...

A photographic camera designed to produce reproduction film of visual information (pictures, line drawings, graphs) for...

Rare earth dopants refer to elements from the lanthanide series, also known as rare earth elements, that are intentionally...

The light formed by visible radiation that, in traveling from light source to object, undergoes one or more reflections. In...

Illumination in which the light source is imaged at the object.

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

Spectrophotometry in which radiation of two separate wavelengths, usually one in an absorption band and the other not, pass...

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

The photographic recording of an action by taking a series of still pictures at regular intervals throughout the action.

A phase screen, in the context of optics and wave optics, refers to a surface or medium that introduces a phase delay to an...

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

Light produced when a metal is bombarded with high-velocity electrons causing small amounts of the metal to vaporize and...

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

Translucent collector developed to compensate for the partial blocking of a flat surface's collection angle that normally...

High harmonic generation (HHG) refers to a nonlinear optical process in which intense laser light interacts with a gaseous...

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

The observed time dependence of the transmittance of a step of radiation through a given medium.

Transmission in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

Handheld optical laser device containing a semiconductor or DPSS source. The output is corrected via internal collimating...

A medical imaging device that uses a ring of crystal/photomultiplier tube assemblies encircling the patient to detect gamma...

In an image, the orientation and magnitude of the rate of change in intensity at any point.

An analog signal capable of being modulated as to frequency, amplitude or phase to carry information.

A cathode-ray tube combined with an electrostatic storage unit that is used to introduce, store and retrieve information...

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of...

Etaloning is an optical phenomenon that occurs in imaging systems, particularly in devices such as spectrometers,...

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

A spectrograph that functions in a vacuum and therefore eliminates any air-absorption of the emission being surveyed.

A source of radiation.

The process by which the light from the images of photographic film is encoded into electrical signals for video...

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

The graph of the oscillating variations composing the wave of a video signal.

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

The placement of a device or an additional circuit into a feedback control system to improve its response in relation to a...

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

Off-axis paraboloid and ellipsoid mirrors are specialized optical components used in various optical systems, particularly...

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

A photodiode having a conducting grid that covers the surface of the photodiode junction and intercepts and wastes some of...

An afocal optical device made up of lenses or mirrors, usually with a magnification greater than unity, that renders distant...

A television camera tube that preceded the development of the vidicon tube and incorporated a method to separate reflected...

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

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

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

A high-intensity source of incoherent white light in which a capacitor is discharged through a tube of xenon gas; often used...

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

Characteristic of optical correlators in which invariance to more than one distortion parameter per axis of the processor is...

A device that consists of two types of mode converters, one of which must be magnetic. It is nonreciprocal because the...

A transparent dielectric film, bounded by material of a lower index of refraction, capable of guiding light.

A homogeneous optical medium or coating that transmits only in particular regions of the spectrum. It is used to change or...

The imaging of two photographs of a stereo pair, in complementary colors, for the preparation of contour maps.

A type of interferometer in which two coils of optical fiber are arranged so that light from a single source travels...

Characteristic of an absorber in the IR region, whereby absorption increases as a direct function of the intensity of the...

The reflection in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

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

A stimulus that contains equal energy at each wavelength in the visible region of the spectrum.

Characterizes the significant solar radiation at the surface of the earth, so named because its spectral range extends only...

Expression of the nondimensional coefficient of the heat transfer in a convection process.

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

The characteristic of displaying three colors when observed in as many separate directions.

An arc lamp whose carbon electrodes are enclosed in a transparent chamber, resulting in an arc that is steadier, lasts...

Scattering caused by the interaction between ingoing and outgoing particles of the same type, with no loss of kinetic energy.

The analysis and measurement of the fluorescence emitted by a source. Fluorometric processes are more sensitive than light...

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

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

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

A prism made of two elements cemented together that, depending on its orientation, inverts or reverts an image. It may be...

A term describing an antireflection coating that may be applied to optics that cannot tolerate the high temperatures usually...

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

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

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

The site behind the lens system in a camera where photographic media are positioned for exposure.

3D Laser Triangulation - A technology that allows sensors to probe the surroundings. Laser triangulation systems have an...

The splitting or shifting of spectral lines or energy levels caused by the application of a strong transverse electrical...

A digital imaging method whereby the first gray level of each sequential point-by-point sample and its position in the...

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

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

An electrochemical process of metal fabrication using an electrolyte, an anode to supply the metal, and a control of the...

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

An assembly of multiple prisms that disperses incident light into its spectral components without deviating light at the...

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

Operates with light collectively emitted by the recombination of free electrons and ions in the plasma state.

The interaction between a photon and an energetic electron, caused by collision, that transfers energy from the electron to...

An electron tube whose electrical characteristics will not be affected by gaseous ionization because of its high degree of...

A two- or three-dimensional space grating formed when ultrasonic beams with varied paths of propagation intersect.

The study of radioactive substances and high-energy radiations such as x-rays and g-rays.

The visual perception of contrasting forms is more difficult if the forms have the same luminance but different...

A colorimeter is a device used to measure and quantify the color characteristics of an object or a light source. It provides...

A single positive lens or group of lenses used in a projection system to collect light from a source and cause it to...

The portion of light scattered when traveling through a unit thickness of material.

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

The use of optical or electronic recording systems to extract information from the terrain, while aloft, for reconnaissance...

A term used to denote a difference in magnification along mutually perpendicular meridians. Anamorphic systems are basically...

Videography refers to the process of capturing moving images and recording them in a digital format. It involves the use of...

The point spread function (PSF) is a fundamental concept in imaging that describes the response of an imaging system to a...

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

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

An alexandrite laser is a solid-state laser that utilizes a synthetic crystal made from the rare earth element alexandrite...

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

A solid-state laser consisting of active atoms or ions of a transition metal, rare-earth metal or actinide, imbedded in a...

A telescope objective with excellent spherochromatic correction, consisting of a meniscus crown and a meniscus flint, both...

A photographic emulsion of the silver-halide type that is used to record the path of a charged traveling particle. The...

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...

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or...

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

Sharp and narrow absorption lines found in the spectra of stars. They result from the absorption of a part of a star's...

Photovoltaic (PV) refers to a technology that converts sunlight directly into electricity using semiconductors. The term...

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

Photoconductivity that may be extended as far as the microwave region because of the absorption of photons by electrons.

A crystalline material with a high electro-optic coefficient, capable of operating at short wavelengths, with applications...

The determination of the temperature of a source by the detection of its incandescent brightness.

A process for the production of optical fibers. A glass bait is rotated in a traversing flame of a reaction burner....

A diagram used to represent the trichromatic variables of the components in a three-color combination.

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

A chemical compound that exhibits a reversible change in its absorption spectrum upon irradiation with given wavelengths of...

In image processing, any operation that strengthens information about the edges of objects displayed. Three types of spatial...

An array of optically distinct fibers that are fused into one strand. They are used to keep the resolution efficiency of the...

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

Biometrics refers to the automated recognition of individuals based on their physiological or behavioral characteristics....

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

In ultraviolet and fluorescence photography, the term applied to the filter used in the photographic system and with the...

The property of an optical system whereby only the effects of diffraction determine the quality of the image it produces.

The photographic filming of the action of x-ray images recorded on a fluorescent screen by means of large lens apertures and...

In photonics, a lattice refers to a periodic arrangement of optical elements or structures, often on a microscopic or...

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

(SALI) A type of spectroscopy in which neutral atoms or molecules are ionized by an excimer laser beam and then measured by...

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

the photography of very close, and typically small objects with a magnification of approximately 1:1

An electro-optic modulator (EOM) is a device used to modulate the amplitude, phase, or polarization of light waves using an...

A statistical means of characterizing the failure of a fiber or device as related to strain or time. Results are plotted on...

In positioning, the friction that prevents immediate motion when force is first applied to a body or surface at rest.

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

A cathode-ray tube that serves as a picture tube in a television receiver. The signal representing the picture intensity is...

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

A spectroradiometer having a means to scan different regions of the light spectrum, providing simultaneous representations...

A sensing or image-forming detector that serves to convert infrared rays into visible signals for communication purposes....

A bench photometer that depends on the inability of the eye to distinguish color in brief flashes of light. Any difference...

A lamp that yields a nonluminous flame; used in the spectroscopic analysis of radiation emitted by a substance placed in the...

The frequency of a wave divided by its velocity of propagation; the reciprocal of the wavelength.

The effect that characterizes an intense laser beam that is passed through an absorbing medium, causing the absorbed energy...

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

A small optical polishing machine intended for polishing the surface of a metal specimen before etching for examination...

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

The lowest excitation power level at which a laser's output is mainly the result of stimulated emission rather than...

A lens, one surface being a cartesian oval, that produces an aplanatic condition.

A filter that transmits light in a series of sharp, widely spaced wavelength bands by its sandwich construction of...

A device that uses a photoelectric cell to determine the level of oxygenation in the blood.

Hydrophilic is a term used to describe substances or materials that have an affinity for water. The word hydrophilic comes...

An electrically excited laser having carbon monoxide as the lasing material and in which lasing occurs in a partial...

Laser active elements typically refers to the substances or materials within a laser system that play a critical role in the...

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

1. A strainmeter capable of measuring the change in the relationship between two reference points, provided that the points...

Process of analysis in which the analyte substance is distributed in a matrix before laser desorption. This method avoids...

The frequency space between consecutive transmission peaks in the transmission spectrum of a Fabry-Perot interferometer or...

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

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

A metal coil or coils wrapped around the outside of the neck of a cathode-ray tube. Current passing through the coils...

An electronic flash tube capable of repeated operation at hundreds or thousands of flashes per second for long periods.

A chemical substance that exhibits fluorescence when excited by ultraviolet radiation, x-rays or an electron beam. The...

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

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

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot onboard. UAVs are remotely...

An electric arc that is formed in mercury vapor through which an electric current flows. The intensity of the illumination...

A photographic method used to obtain an image of a subject by means of its reflectance of incident ultraviolet radiation. An...

The capability of the spatial distributions of incident and reflected flux to interchange completely without alteration of...

The degree to which a predetermined or previous setting of a positioning device can be duplicated by observance of the...

A scale attached to a microscope eyepiece that is seen superimposed on the image and that is used to measure the dimensions...

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

A precision positioning device used to produce rotary motion.

In microscopy, a calibrated scale on a slide that may be viewed to determine the exact magnification factor of the...

A homogeneous solid solution with crystal lattice sites occupied, at random, by the molecules or ions of two or more...

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

The process in which the normal rate of fluorescent emission from a substance is enhanced by virtue of the optical gain of...

A microlens array is a grid-like structure composed of numerous small lenses, typically arranged in a regular pattern. Each...

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

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

Optical tweezers refer to a scientific instrument that uses the pressure of laser light to trap and manipulate microscopic...

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

A physical source of radiation, as contrasted to illuminant. See illuminant.

The magnitude, expressed in cycles per second, of the alteration of the wave frequency observed as a result of the Doppler...

The representation of arbitrary functions as the superposition of sinusoidal functions whereby the representations...

Operation in which the minimum detectable signal has its limits set by the thermal noise of the detector, the load...

The creation of a chemical reaction in a substance when radiation is directed to it.

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

Additive manufacturing (AM), also known as 3D printing, is a manufacturing process that involves creating three-dimensional...

End-fire coupling refers to a method of coupling energy into or out of a waveguide, transmission line, or antenna, where the...

A defect in the cleaved end face of an optical fiber in which a portion of the edge has broken away; the complement of lip.

A disc contained within an electronic cell counter for regulating light transmission.

A reflection grating is an optical component that consists of a series of closely spaced, parallel reflecting surfaces or...

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

Particle acceleration refers to the process by which charged particles, such as electrons or protons, gain kinetic energy...

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

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

A hologram facet illumination technique in which the illuminating beam is twice the size of the hologram facet so that full...

The power that gives rise to the production of energy at the rate of 1 joule per second.

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

A source that attempts to create the characteristics of an ideal blackbody. It consists of a cavity, generally spherical,...

In television, the number of individual pixels that can be distinguished in a horizontal scanning line; also called...

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

The removal of the zero-order component of the Fourier spectrum distribution of an object with a small, opaque absorber or...

An analysis used for problems of wave propagation. The principle notes that each point of an advancing wavefront is the...

The term quantum refers to the fundamental unit or discrete amount of a physical quantity involved in interactions at the...

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

1. That action occurring when light passes through an optical interface at other than normal incidence, i.e., refraction. 2....

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

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

Naturally occurring planes in crystalline substances that provide easy points for separation.

A method used to detect internal or residual microstresses in a material by using a laser beam to locate changes in...

A variation of tomography, which is a means of visualizing any one of a large set of parallel planes in the patient. A...

The series of interference bands that appear in the spectrum when a specified glass plate is inserted into a spectroscope,...

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

A flat, round micrometer that is placed in the focal plane of a telescope to measure difference in right ascension and...

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

A lens or lens surface that is a combination of a sphere and cylinder.

A photovoltaic device that consists of multiple p-n junctions to produce a greater efficiency when in use than that of...

An accurate cathode-ray tube display used to provide visual representation stored in a computer for the interpretation and...

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

Electromagnetic radiation present upon the open aperture of the source within an operating environment.

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

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

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

A photon jet is a narrow, highly collimated beam of light that is formed when light interacts with small dielectric...

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

In the context of optics and lasers, a transverse mode refers to a specific spatial pattern of the electric field within the...

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

Computer numerically controlled (CNC) grinding is a manufacturing process that utilizes computerized controls and precision...

The angle between the most divergent rays that can pass through the lens to form an image. In a birefringent crystal light...

The transmission of a color photograph by separating the colors into varying intensities of red, blue and green, and then...

Measures by heterodyning interferometry the local slope of a vibrating sample. The method allows the reconstruction of a...

1. The near total absorption of plane-polarized light by a polarizer that has an axis perpendicular to the plane of...

Chemical vapor deposition is a process of applying dopants to a glass bait by flame reactions of gaseous compounds. See also...

In its natural or original position.

In a dual-ring local area network, a node that is connected both to the primary, active ring and also to a secondary ring...

A method of measuring negatively charged phase ions using a color-center or lead-salt diode laser.

The portion of a reproduced image having the greatest luminance.

Continuous wave (CW) refers to a type of signal or transmission where the signal is constant and does not vary with time. In...

A photoconductive cell having cadmium sulfide as its photoconducting material for the production of a very high dark-light...

An optical element designed to correct each zone of a reflector or refractor for spherical aberration.

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light...

Superresolution refers to the enhancement or improvement of the spatial resolution beyond the conventional limits imposed by...

The micrometer-size depressions that store data digitally in an optical data storage medium.

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

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

The distribution of gray-scale values in an image.

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

Optical design and engineering services involve the development, customization, and optimization of optical systems and...

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

A form of prism invented by H.W. Dove. It resembles half of a common right-angle prism in which a ray entering parallel to...

The exact mathematical description of the interactions of matter and intense electromagnetic fields, such as those that...

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

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

A large telescope mirror fabricated from several smaller sections.

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

Solar radiation intensity existing in free space at the mean solar distance of the Earth. Commonly expressed in g cal...

The condition of identity of visual appearance.

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

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

Abbreviation of "synchronization.'' In television, the timing signals used to drive the scanning process. Horizontal...

The method that, by measuring the absorption along an atmospheric path at wavelengths ranging from two to a continuum, can...

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

Pertaining to radiation or particle emission, whereby the emission is produced with minimal energy spread.

In a crystal, its subdivision into polyhedral blocks of macroscopic sizes, with discontinuities contained in the lattice...

The mechanical modification of the shape of the cornea to correct a vision defect.

Capability requirement for optical switches for transmission lines to process arbitrarily polarized light because of the...

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

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

An image-forming instrument in which a strong electrostatic field causes cold emission of electrons from a sharply rounded...

The separation of unpolarized light into two plane-polarized elements by a doubly refracting crystal. When a crystal, such...

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials...

A photographic recording instrument that measures deviation from the vertical of a drilled well or mine.

The presence, within the body of the glass, of extraneous or alien material. See seed; striae.

A terahertz spectrometer is a scientific instrument used to measure and analyze the properties of materials in the terahertz...

Source of radiation defined or specified by its spectral power distribution.

Systeme Internationale d'Unites, the international metric system of units.

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

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

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

An infrared imaging device composed of a detector array and readout electronics. It may include a cryogenic cooling system....

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

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

In optics, the changing of the relative curves of a lens without changing its refractive value.

In laser pumping, parasitic absorption that occurs at certain wavelengths, decreasing pump efficiency and gain.

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

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

A substance capable of converting solar radiation into thermal energy.

A color center laser whose output is coupled to an external control laser cavity and then fed back to the main laser cavity...

Thermal interface materials (TIMs) are substances or compounds used to enhance the thermal conductivity between two surfaces...

A laser using a dye solution as the active medium whose resonator is formed into a ring (or a triangle or another shape) by...

The unchanging nature of spectral reflectance as vegetational density increases to the point where additional increases in...

The amount of spatial noise detected equivalent to the output emission location of the giving source.

A technique for detecting and measuring atmospheric pollution, in which an oscillating mirror directs half the incoming...

An object that has a sinusoidal variation of luminance. Its image will have a sinusoidal variation of illuminance and the...

1. The term used to describe any of the many instruments used to remotely record physical dimensions, such as strain,...

A type of asynchronous shutter device that is used particularly in CCD sensor applications to capture an image of a...

The intensification of a latent image, because of exposure to light to which the emulsion is otherwise insensitive.

The general term for the application of light to a subject. It should not be used in place of the specific quantity...

A mechanical device designed to smoothly vary the effective diameter of a lens, thereby controlling the amount of light...

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

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

Optical cements and adhesives are specialized materials used in the assembly and bonding of optical components in optical...

A surface imperfection caused by a polisher running dry too long. It occurs with felt or plastic polishers, and may appear...

Essentially, a hologram of a hologram, in which the first-generation hologram is masked with a narrow slit. During image...

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

A graphic reproduction of an object formed by a microscope or another optical system. Also an instrument used to make tiny...

An optical instrument used to determine the distance to a target being viewed. Two similar optical systems view the target...

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

Ultraviolet (UV) fiber optics refers to optical fibers that are designed and optimized for the transmission of ultraviolet...

Specified curved optic intended for maximum collection of light, including off-axis rays, before leaving the exit aperture.

A type of optical microscope that allows the specimen being viewed to be irradiated by ultraviolet, violet and occasionally...

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

Observed when alterations in the luminous sterance at the contour of an object create the illusion of the outer zones...

Characterizes a substance whose plane of polarization is rotated counterclockwise as the observer looks through the material...

A grating that specularly reflects the specified long radiation wavelengths and diffracts the shorter wavelengths off in...

A small instrument containing a picture support and a pair of magnifying lenses so arranged that the left eye sees only the...

The transmission and reception of information by optical devices and sensors.

A system incorporated into fiber optic data communications characterized by several spatially distributed terminals that are...

A laser diode module is a compact device that incorporates a laser diode, optics, and often other components into a single...

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

A laser device used to establish a location or target usually for detection by an impact source e.g. missiles and guided...

A variation of tomography in which several photographs of a patient are taken at different angles, and back-projection of...

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

A doubly refracting mineral used to produce polarizing prisms. It is uniaxial negative and in the trigonal division of the...

A countermeasure used against heat seeking missiles to reduce their effectiveness. Normally it involves the emittance of...

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

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

A high-frequency pulse-rate laser with an output limited by the heat capacity of the laser medium. Instead of having...

In optical communications, the translation of optical signals into radio signals, lowering their frequency in detection from...

A mask-alignment microscope used to produce and inspect microcircuits in the electronics industry. It provides flat-field,...

An electric cell having two electrodes of unlike metals immersed in a solution that chemically affects one or both of them,...

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

A double-surfaced catadioptric spherical mirror whose spherical first surface consists of a negative meniscus (concave) lens...

The time domain is a concept used in signal processing and analysis to describe signals in terms of their behavior over...

A Pockels cell, also known as an electro-optic modulator, is an optical device used to control the polarization of light by...

A method used to produce precision spherical and aspheric molded glass lenses without grinding or polishing.

Developed for use in military reconnaissance systems, it consists of a polygonal mirror, drive motor, interface between...

The pattern of physical or chemical changes that has taken place in a photographic emulsion, by its exposure to light, that...

1. That portion of the aperture that functions to collect energy and deliver it to the final system detector. 2. For an...

1. A compound lens consisting of two elements. If there is an air space between the elements it is called an...

The moving spot of light emitted by a source, generally a cathode-ray tube, to illuminate specific points of an area...

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

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

The production of a block by attaching the optical elements to a plate by means of individual buttons of pitch or other...

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

In optics, "mode beating" refers to an interference phenomenon that can occur in laser systems with multiple longitudinal...

A technique based on the principles of laser trapping and used to manipulate the position of small particles by gradually...

A CIE index describing the changes in color of standard test objects when the illumination is changed from a standard to a...

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

Essentially, noise that cannot be predicted. Therefore, even if the magnitude of sound or oscillation in a system is known...

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

A prism formed by dividing a Nicol prism in a plane parallel to the path of vibration of the transmitted light and taking...

A device designed to detect microwave modulation and to mix modulated and unmodulated laser beams. It consists of a...

Diffraction efficiency is a measure of how effectively a diffractive optical element (DOE) or diffraction grating directs...

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

1. The process by which an atom acquires energy sufficient to raise it to a quantum state higher than its ground state. 2....

A filter designed to decrease the luminosity of the sky without decreasing that of the landscape in the foreground. A filter...

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

Diffuse stray light at the image plane of an optical system that results in reduced contrast and resolution.

Change of sensitivity of the eye leading to changed color perception.

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

The light from a nonselective diffuse reflector due to the standard illumination of the scene to be televised.

Also known as cathode rays. Formerly, this term described a stream of electrons emitted from the cathode of a gas-discharge...

A ghost image that has the reverse lightness relations of the original image. This phenomenon is a common optical illusion...

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

1. In detector technology, the long wavelength at which detector response falls to a set percentage (usually 20 or 50...

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

A fiber optic sensor is a device that uses optical fibers to detect and measure physical, chemical, biological, or...

The multiple beam form of Brewster's fringes formed when the two plane-parallel plates have high-reflecting surfaces.

Refers to the variety of techniques that use the interference pattern produced by laser light diffusely reflected by an...

A visual spectrophotometer with a rhomb located directly before the entrance aperture of a constant-deviation...

An adaptation by Philips and Sony of their audio compact disc technology for optical disc data storage and retrieval....

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

Laser optics refers to a broad category of optical components and systems designed for manipulating and controlling laser...

An optical circuit, either monolithic or hybrid, composed of active and passive components, used for coupling between...

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

A magnon is a quasiparticle representing a quantized spin wave in a magnetic material. In other words, it is a collective...

Electromagnetic radiation that is emitted by an electron as it is accelerated or decelerated while moving through the...

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

Color correcting; chromatic aberration corrected.

The degree to which a pixel in a digital image represents the analog brightness of the corresponding point in the original...

A fast, wide-angle lens used in television and photographic cameras, with excellent overall correction, but subject to...

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

A lamp in which the ionization of the inert gas contained in it produces a glow in the space close to the negative electrode.

A memory system composed of a stack of holographic plates, a mode-locked laser and a rapid detector array. Ultrashort laser...

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

A device used to project a small area of light on a screen for indication.

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

Piezoelectric motion systems are mechanical systems that utilize piezoelectric materials to generate controlled motion or...

The theorem stating that, when the sampling period in a recorded sample hologram is matched to the object spectrum, the...

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

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

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

The freeing of electrons from an electrode into the surrounding space.

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

A device used to detect and measure small amounts of rotation. The rotating object contains a reflecting surface from which...

A state in which the human eye has very little or no power of accommodation. A common and normal condition in the eyes of...

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

An approach to optical character recognition based on matching the input character against a set of stored prototypes.

A radar system that uses electro-optic rather than microwave instrumentation and methods to perform its acquisition and...

A lens that has one convex surface and the other concave.

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

A process of color photography in which colors are added one to another in the form of light, rather than as colorants, to...

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

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

1. In fiber optics, a protective material applied as an optical fiber cover that has no optical function. 2. In image...

A type of x-ray that is capable of deep penetration; its wavelength is about 10-8 cm.

Operation in which the dispersion of a pulse limits the distance between repeaters in optical systems. Waveguide and...

The random noise having a spectral density that is substantially independent of the frequency over a specified frequency...

A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its...

The ability of the human eye to adjust itself to an alteration in the intensity of light.

The large, usually flat surface onto which an image is projected for viewing. May be reflecting or transmitting (rear...

In a charge-coupled device, the detection of charge collected by the transport register rather than by the image-sensing...

With respect to television, a potentiometer that allows variation of the intensity of the different elements of an image and...

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a...

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

In optics, a plane that emits a flux proportional to the cosine of the angle of the normal; dense opal glass is an example.

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

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

A means of adjusting the sharpness of an image automatically, with a sensor for estimating distance or contrast and a drive...

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

The spectrographic analysis of matter that is in a cooled state. Generally, a mechanical refrigerator is used to lower the...

A laser having a rare-earth chelate within a plastic host as the lasing material. The chelate laser is easily pumped and has...

Referring to the bandwidth and spectrum location of the signal produced by television or radar scanning.

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

In optics, the term denoting the lack of a fixed phase relationship between two waves. If two incoherent waves are...

A small television tube originally developed for closed-circuit television. It is about 1 inch in diameter and 5 inches...

1. In astronomy, the angle measured clockwise (eastward) in a horizontal plane, usually from north (true north, Y-north,...

Wave of radiation identified by individual fluctuations of electric and magnetic fields.

A measurement of the spatial resolution of a line or area array in an optical character recognition scanning device.

Machinery used to grind and finish a component, such as a lens or prism, to a desired precision. Usually such machines carry...

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

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

The application of aerial photographs as a means of measurement in map making and surveying.

Capacity of a vision system to capture an image of an object in motion and to resolve the direction and speed of that motion.

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

A breakout cable, also known as a fan-out cable or breakout assembly, is a type of cable that combines multiple individual...

The process of heating and slowly cooling a solid material, like glass or metal, to stabilize its thermal, electrical or...

The lateral distance between a vertical line drawn through the geometrical center of the distance portion of a multifocal,...

The absorption of a photon raising an electron across the forbidden gap from valence to conduction band of the semiconductor...

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

Bar pattern represented as a sine curve in which the light distribution varies in one direction.

In fiber optics, the use of a detector to study the range of refractive indices achieved at various wavelengths. This...

A lens aberration. The chromatic variation of spherical aberration.

A device that provides means for accurately moving minuscule tools over the surface of a microscopic object. The motion...

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

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

A data transfer function that moves a rectangular group of pixels between bit maps. Often used in displaying cursors and...

Laser powder bed fusion (LPBF) is a type of additive manufacturing (AM) or 3D printing technology that uses a high-power...

A compound lens, the dimensions and materials of which have been so chosen that the lens is appreciably free of aberrations.

An optical channel monitor (OCM) is a device used in optical communication systems to monitor and analyze the performance of...

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

The study concerned with the stimulation of chemical activity by laser light as a result of the absorption of photons by a...

A lumen is a unit of measurement used to quantify the amount of luminous flux, which is the perceived power of light. In...

The steady state of temperature exhibited by a material that has absorbed and emitted radiation equally.

Light present in the environment around a detecting or interpreting device, especially a machine vision system, and...

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

A computer-generated kinoform used for data processing because of its use of incoherent light and its wide field of view,...

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

Azimuthal polarization refers to a specific polarization state of light where the electric field vector of the...

Means of correcting laser postweld shift. The correction procedure is applied to optoelectronic systems such as laser diode...

Production of a repeated image of a transmitted beam through a diffractive optical element such as a holographic card or...

An X-Y electrically addressable series of arrays with individual electron emitters bombarding a phosphor-coated transparent...

Synonym for multimode distortion. Also called mode dispersion.

A device for measuring diffraction grating efficiency at any angle of incidence, consisting of a reflectometer wherein the...

A group of solar cells that are electrically contacted and physically arranged so that they may be oriented in the direction...

Also known as mesosphere. A level of the atmosphere, extending from the stratosphere to the ionosphere, that is noted for...

High-modulus elastic fibers that exhibit the following differences from conventional elastic fibers: Increasing temperature...

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

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

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

A solar simulator is a device used to replicate the spectrum and intensity of sunlight in a controlled environment for...

The third dimension (depth or Z-axis) in an imaging system.

An LED (light-emitting diode) is a semiconductor device that emits light when an electric current passes through it. LEDs...

A specific form of phase shifting interferometry - commonly referred to as multiple wavelength phase shifting interferometry...

Scalar diffraction theory is a simplified approach used to describe the propagation of electromagnetic waves, particularly...

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

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

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

A condenser composed of a paraboloidal reflector and used for dark-field illumination.

Elastic deformation of a dielectric caused by volume force when the dielectric is placed in an inhomogeneous electric field.

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

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

A plane passing through a crystal that has the optic axis of the crystal and the light ray under consideration.

That branch of metallurgy that uses electron microscopic techniques in the examination of the nature of metals.

The complex function, H(f), equal to the ratio of the output to input of the device as a function of frequency. The...

Second-harmonic generation (SHG) is a nonlinear optical process that occurs when two photons with the same frequency combine...

The method by which Thomas Young in 1802 disproved Newton's corpuscular theory of light by the formation of interference...

An optical system used to collect infrared energy from a scene using scanning optics with a point or line detector, as...

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

A shower of cosmic rays whereby a high-energy electron produces one or more photons that convert into electron pairs, the...

A mirror with a coating that reflects infrared radiation and transmits visible light.

A phosphor that has the ability to convert into light emission a portion of energy lost by ionization when a charged...

A pinhole camera used to record a radioactive tracer's distribution in a subject by means of a scintillation counter or a...

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

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

A filter that suppresses a given range of frequencies, transmitting only those above and below that band. Also called...

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

Abbreviated SoC. A single chip containing all the electronic circuits required for a complete, working product. SoCs are...

A microscope designed with two eyepieces (oculars), permitting the use of both eyes when viewing through the instrument.

A reflecting prism that inverts the image. The image is reflected four times internally and emitted laterally. The prism is...

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

Gram-negative bacteria are a group of bacteria that possess a cell envelope composed of a thin layer of peptidoglycan...

Used to detect radiation from the infrared region. The functional process includes absorption of infrared radiation, which...

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

Consists of a pair of radio telescopes concentrated on a single celestial object. This technique creates a single radio...

A process in which a mixture of one or more monomers, plus a catalyst, polymerize under exposure to light radiation....

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

The desensitization of the first photographic exposure after it has been subjected to high-intensity radiation.

An obsolete term once used to describe a unit of radiation dosage.

The transmission of data in groups (packets) of information~comma~ each handled as an aggregate.

A reflecting prism that is rhomboidal in shape. It has two parallel transmitting faces, and two parallel reflecting faces;...

A television system that does not broadcast television signals but transmits them over a closed circuit.

The initiation of the beam in a cathode-ray tube.

The optical energy transfer between ions of differing atoms.

The term "metaverse" refers to a collective virtual shared space, created by the convergence of virtually enhanced physical...

A number that indicates the magnitude of the shift in a solid of positive and negative charges in opposite directions when a...

Injecting a gas (usually nitrogen) with a very low moisture content into the body of an optical instrument to create a...

In an optical system, noise created by mode-dependent optical losses and variations in the distribution of radiant power...

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

Location on the CIE chromaticity diagram which produces the color white for a given light source at a specified temperature.

The transform defining that, if a reference beam is a divergent spherical wavefront, then the reconstructed image will be...

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

The spectral transmission window in silica-based fibers between 830 and 850 nm.

A small handheld instrument consisting of a slit and collimator that feeds light into a small direct-vision dispersing...

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

An artificial star used to aid in adaptive optics imaging of the sky. The guide star is provided from a telescope system on...

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

A wave of radiation that has undergone refraction.

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

A type of glass used in near-infrared optical components, in which germanium is used as a cation instead of silicon.

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

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

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

An echelon in which the dihedral angle between the faces of the groove is 90°.

Recombination of only the light that is correctly dispersed by the first stage of a polychromator through its wide...

An optical cable that is connector terminated. Generally, an optical cable that has been terminated by a manufacturer and is...

A phenomenon, exploited for medical imaging, in which the nuclei of material placed in a strong magnetic field will absorb...

The description of the refractive index along a fiber diameter.

An arrangement of optical fibers in a bundle whereby the geometric configuration of the input end differs from that of the...

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

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

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

An instrument that can preselect intervals, often in increments of 1, 10 or 100 ns, for the generation of electronic pulses...

Topology is a branch of mathematics that focuses on the properties of space that are preserved under continuous...

A two-dimensional scanning process, in which a slow sector scan, propagated in one direction, is superimposed at right...

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

The interferometric analysis of a complex object by utilizing the three-dimensional hologram. By causing a laser beam to...

A display in which regeneration takes place serially at a fixed speed in a set pattern through the scan lines.

The interval between direction of signal to a light-emitting diode and attainment of 10 percent output current in the...

A liquid, usually of a specific refractive index and dispersion, serving as an interface between two solids to form a...

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

The superposition of satellite or aerial images with a map in order to process and remove distortion. Uses reference points...

In data communications, the simultaneous operation of a circuit in both directions is known as full duplex; if only one...

A photocathode having a P-type semiconductor with a work function less than its bandgap. The photocathode can release a...

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

The principle that a light ray extending from one point to another will, after any number of reflections and refractions,...

In visual perception, the smallest difference in illumination perceived on the average.

Swept-source optical coherence tomography is an imaging technique used in medical diagnostics, particularly in...

The ratio of the active core area of a fiber bundle to the total area at its light-emitting or receiving end.

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

A transducer is a device or component that converts one form of energy into another. It is commonly used in various fields,...

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

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

An infrared-transmitting optical fiber with a hollow core; it can be square, round or rectangular in cross section. Capable...

The Foucault test is performed by moving a knife edge laterally into the image of a small point source. The eye, or a...

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

Also called scanning laser acoustic microscope. A device that uses high-frequency ultrasound waves to penetrate surfaces. A...

Also known as Fresnel reflection. That portion of the incident radiation that is reflected from the surface of a refractive...

In a single-mode optical fiber, the wavelength that causes material dispersion and waveguide dispersion to cancel each...

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

A photonic crystal that comprises magneto-optical material such that the optical response of the device depends on the...

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

Holography is a technique used to capture and reconstruct three-dimensional images using the principles of interference and...

The apparent difference in brightness between light and dark areas of an image. For a light target against a dark...

An alternate term for lateral chromatic aberration. See chromatic aberration.

A device used to measure power loss in fiber optic connectors, cables or systems.

Propagation of electromagnetic waves through the Earth's atmosphere in a path that conforms to the curvature of the Earth...

The span of frequencies within which a single channel of broadcast television must fall; in the US, it is 6 MHz.

Amplification; the result of the excess of stimulated radiation over absorbed radiation.

Luminous flux incident per unit area of a surface; luminous incidence. (The use of the term "illumination" for...

Two plane mirrors that are not wholly located in the same plane. When light from a point source or slit reflects from the...

The electric field associated with an electromagnetic wave and thus with a lightwave. The electric vector specifies the...

A laser or laser system positioned within an enclosure to prevent dangerous optical radiation from leaving the enclosure.

Loss intrinsic to the fiber caused by parameter (core dimension, profile parameter) mismatches when two nonidentical fibers...

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

A fluid used to decrease the temperature rise produced by friction or other causes.

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

Backscatter refers to the phenomenon in which radiation or waves are scattered backward, opposite to the direction of the...

A type of birefringent polarizing prism that transmits the extraordinary ray and removes the ordinary ray through total...

A phase-modulated sensor is a type of sensor that uses modulation of the phase of a signal to measure changes in a physical...

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

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

A means of achieving higher peak powers and more efficient harmonic generation by narrowing the pulse width and thus...

The circle that contains the slit, grating and primary astigmatic focus of a concave diffraction grating.

Device that operates by interaction of incident radiation with semiconductor based material in order to produce an...

An infrared source combined with reflecting projection optics to illuminate a target making it visible when observed through...

The Lorentz oscillator model is a theoretical model used in physics to describe the response of a charged particle (such as...

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

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

An instrument similar to the spectroheliograph, but having a scanning method that is performed by a pair of rapidly...

Also known as roof prism. A type of prism designed by G.B. Amici. It consists of a roof edge produced upon the long...

Dispersion refers to the phenomenon where different wavelengths (colors) of light travel at different speeds when passing...

A digital imaging method whereby the first gray level in the ordered sequence and the position of the first lengths of all...

Whole slide imaging (WSI), also known as virtual slide microscopy or digital pathology, is a technology that involves the...

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

1. The basic unit of length in the metric system, equal to 39.37 in. or 3.28 ft. 2. Any device or instrument used for...

A microscope design that involves apertures inserted in conjugate plane positions inside the microscope, with one aperture...

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

In reference to infrared, emissions that are like radio waves but that have a higher frequency.

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

Turbidity is a measure of the cloudiness or haziness of a fluid caused by the presence of suspended particles. These...

Generally, the orientation of rays of light striking a surface.

1. A generic term for detector. 2. A complete optical/mechanical/electronic system that contains some form of radiation...

A quantum well is a structure in quantum mechanics that confines particles, such as electrons or holes, in one spatial...

In optical character recognition, the method of dividing a string of characters into separate, distinct characters.

A technique, involving spectrophotometry in the ultraviolet, that is designed to determine the colors of thin-layer...

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

A lens assembly made up of three lens elements that may or may not be cemented.

An edge-emitting light-emitting diode is a type of LED structure where light emission occurs primarily along the edge of the...

Photoconductivity due to the addition of impurities or external causes.

Selection of specific brightness values or minimum threshold levels as contingencies for the display of digital data.

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

The utilization of the light produced when electrical energy is directly converted into light within devices used for visual...

A straight line, real or imaginary, passing through a body and indicating its center; a line so positioned that various...

Also known as the Bragg spectrometer. A system used for the x-ray analysis of crystal structure. In the instrument, a...

A ray that has a nonisotropic speed in a doubly refracting crystal. It does not necessarily obey Snell's law upon refraction...

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

The technique by which an analog image is converted by any of several means into a finite array of points, each represented...

That property of a material that determines that velocity of propagation within the material is the same for all directions.

The real part of the axial propagation constant for a particular mode. The attenuation coefficient for the mode power is...

Thin-film coatings are layers of material applied to the surface of an object or substrate, typically to modify its optical,...

Instruments used by ophthalmologists and optometrists to study the eye. There are, for instance, the ophthalmoscope to...

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

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

An optical recording technique that uses light source(s), a beamsplitting cube, light detector(s) and an optical fiber...

A laser, which stands for "light amplification by stimulated emission of radiation," is a device that produces coherent and...

Flux per unit solid angle leaving a surface in any direction is proportional to the cosine of the angle between that...

A beam of light whose electrical field amplitude distribution is Gaussian. When such a beam is circular in cross section,...

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

A camera that uses a rotating mirror to project sequential images onto lenses that are arranged in an arc. The reflected...

In computer graphics, the point on the display screen where the electron beam is located before the display instruction is...

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

The law given by the formula: that is, the frequency of radiation emitted or absorbed by a system when E2 and E1...

A chemical used in the developing of positive photographs that incites oxidation and thereby dissolves the negative silver...

The coupling of laser or light beams via nonlinear optical techniques such as four-wave mixing to achieve spatial variation...

An element within a three-dimensional data set image.

Nonspecular reflection from a rough surface.

A study of the energies and wavelengths of radiation emitted by atoms and molecules when particular physical conditions are...

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

Illumination of hologram facets with a beam that covers only a small portion of the hologram in order to optimize laser...

A technique for depositing a material coating on metal, ceramic, semiconductor or polymer substrates. The interaction of...

An emulsion in which grains of the photosensitive material silver halide are deposited. Each grain, when exposed to light,...

A factor, F, indicating the increase in shot noise in an avalanche photodiode as compared with the ideal multiplier, which...

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

An electrowetting display (EWD) is a type of electronic display technology that utilizes the principles of electrowetting to...

The system of color classification and description produced by Wilhelm Ostwald.

A type of laser spectroscopy used to measure short-lived isotopes by observing sudden bursts of fluorescence resulting from...

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

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

A type of fiber optic sensor that detects alteration in position, distance, pressure, liquid level or temperature by...

In a laser diode, the photocurrent produced by a photodiode that detects the emission from the rear facet of the...

A laser having a material, such as ruby, that has an energy state structure of three levels: the ground state (1) wherein...

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

A type of ultrasensitive laser spectroscopy that can detect quantities as small as a single atom of some substances and that...

Any noise or current fluctuation that prevents precise measurement of the signal current. Both dark current and signal...

The point of a planet or comet's orbit that is farthest from the sun.

The use of photographs -- motion picture or still -- to establish if a particular event exists.

An instrument used to record the emittance or reflectance of an object by scanning with discrete spectral resolution over a...

A radiation source that, unlike the point source, can be resolved by the naked eye into a geometrical image.

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

A sheet of plastic material containing microscopic crystals of herapathite or some other similar substance that transmits...

The angular difference in the direction of an object as seen from two points of observation. The angle subtended at the...

A wedge in a rangefinder or heightfinder used to displace the image produced by one telescope so that it coincides with that...

The optical diffraction spectra formed, or the method that produces them, when a light beam is transmitted through a...

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

A scanning process in which the greatest amount of radiation determines part of a spiral motion rotating in one direction.

The constant that, multiplied by the frequency of the radiation-producing emission of photoelectrons, determines the amount...

A device used to measure the intensity of radiant energy.

Also known as cathodic etching. Surface etching achieved by bombarding an evacuated surface with gas ions.

In a dual-ring local area network, a node that is connected only to the primary, active ring and not to the secondary ring...

A method of producing an essentially constant output signal from an electronic circuit despite variations in the strength of...

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the...

Topological photonics is a branch of physics and optics that explores the application of topological concepts to the...

Holographic quantity expressed as the ratio of the reconstructed first-order image to that of the incident reconstructing...

Observed lengthening in wavelengths of the optical absorption edge of a semiconductor with the application of an electric...

In physics, nuclear fusion refers to the process in which two atomic nuclei come together to form a heavier nucleus,...

Also called DLIP, a high-speed, high-resolution processing technique that uses high-power, pulsed laser systems to directly...

The code used to describe the United States system of color telecasting.

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