The combination of two waves having the same frequency and amplitude and traveling in opposite directions. Standing waves are indicated by a stationary set of nodes spaced one-half wavelength apart along the propagation direction of the waves.

A fiber optic spectrometer is a device used for measuring the spectral content of light. It utilizes optical fibers to...

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

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

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

A source that attempts to create the characteristics of an ideal blackbody. It consists of a cavity, generally spherical,...

A reticle, also known as a reticule or graticule, is a pattern or set of markings placed in the focal plane of an optical...

With respect to a crystal, having three unequal axes intersecting at angles, only two of which can be equal and only one of...

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

Illumination in which the light source is imaged at the object.

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

A scintillation detector is a radiation detection device that utilizes scintillation crystals to detect and measure ionizing...

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

A linear positioning stage, also known as a linear stage or translation stage, is a precision mechanical device used to...

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

A camera system that uses a fine powder to diffract x-rays from the specimen. A beam of monochromatic x-rays passes through...

A helium-neon (HeNe) laser is a type of gas laser that emits visible red light at a wavelength of 632.8 nm. It operates...

A straight line, real or imaginary, passing through a body and indicating its center; a line so positioned that various...

A CMOS image sensor, short for complementary metal-oxide-semiconductor image sensor, is a type of semiconductor device used...

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

A telescope objective with excellent spherochromatic correction, consisting of a meniscus crown and a meniscus flint, both...

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

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

The total optical power loss caused by the insertion of an optical component such as a connector, splice or coupler into a...

A set of rays through a lens originating at a common point and contained in one plane.

A laser that has a surface-emitting semiconductor gain element coupled to an external mirror designed to complete the laser...

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

The degree to which a pixel in a digital image represents the analog brightness of the corresponding point in the original...

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

A type of optical modulator with potential application in optical switching and displays, in which applied voltage causes a...

Also termed eye distance. The distance between the vertex of the last optical surface of a visual optical system and the...

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

An instrument using a Michelson interferometer, a beamsplitter, two plane mirrors and a detector to give Fourier analysis of...

An acousto-optic modulator (AOM) is a device that utilizes the interaction between sound waves and light waves to modulate...

A method of spectral analysis in which some property of the sample is varied and the corresponding change is measured. The...

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

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

A microlens array is a grid-like structure composed of numerous small lenses, typically arranged in a regular pattern. Each...

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

An infrared light-emitting diode (IR LED) is a semiconductor device that emits infrared light when an electric current...

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

A double-surfaced catadioptric spherical mirror whose spherical first surface consists of a negative meniscus (concave) lens...

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

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

Fused quartz and silica are closely related materials, both composed primarily of silicon dioxide (SiO2), but they are...

A hollow sphere coated internally with a white diffusing material and provided with openings for incident beam, specimen and...

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

A method of creating real three-dimensional models by using lasers driven by CAD software. In contrast to the normal...

A law that uses the square of the cosine between the plane of polarization of a beam of plane-polarized light and the plane...

One optical element of a multielement lens. See optical element.

A mirror employed with a very high incidence angle to form a pair of coherent light sources by reflection, and therefore...

Molecules composed entirely of carbon, in the form of a hollow sphere, ellipsoid or tube. Also called buckyballs....

Modified chemical vapor deposition (MCVD) is a technique used in the fabrication of optical fibers. It is a specialized form...

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

A refracting telescope that yields an erect image by the use of a positive lens for its objective and a negative lens for...

A Pockels cell, also known as an electro-optic modulator, is an optical device used to control the polarization of light by...

Brillouin scattering is a phenomenon in physics where an incident electromagnetic wave (usually light) interacts with...

A crystal, glass, or quartz slicing and cutting machine is a specialized piece of equipment used in the manufacturing...

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

Piezoelectric transducers are devices that utilize the piezoelectric effect to convert electrical energy into mechanical...

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

A mechanical device designed to smoothly vary the effective diameter of a lens, thereby controlling the amount of light...

A multiple-beam interferometer, usually consisting of two flat plates, with high reflective ability. The plates are set...

The simplest lens in which all primary aberrations may be corrected. It consists of two positive crown elements on either...

An optical element having plane-inclined surfaces. Usually the faces are inclined toward one another at very small angles....

A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its...

There are three types of telecentric lenses: -Image-space telecentric lenses are those in which the aperture stop is...

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

The formula describing the spectral radiant emittance of a perfect blackbody as a function of its temperature and the...

Specified curved optic intended for maximum collection of light, including off-axis rays, before leaving the exit aperture.

A transmission electron microscope (TEM) is a powerful microscopy technique that uses a beam of electrons to create...

Optical materials refer to substances or compounds specifically chosen for their optical properties and used in the...

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

A scientific CMOS (complementary metal-oxide-semiconductor) camera is a type of digital camera specifically designed for...

Total internal reflection fluorescence (TIRF) microscopy is an advanced fluorescence microscopy technique that leverages the...

The term quantum refers to the fundamental unit or discrete amount of a physical quantity involved in interactions at the...

Optical fiber optic switches are devices used in optical fiber communication systems to selectively route optical signals...

An EMCCD (electron-multiplying charge-coupled device) camera is a type of scientific camera specifically designed for...

A type of interferometer in which two coils of optical fiber are arranged so that light from a single source travels...

Optical coherence tomography (OCT) is an imaging technique used in medical diagnostics and biomedical research to obtain...

An etalon is an optical device that consists of two parallel reflecting surfaces separated by a precise and known distance....

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

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

An optical instrument used to isolate a narrow bandwidth of optical radiation using a diffraction grating as the dispersive...

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

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

The number of unique ways in which a part can move in an alignment system. In static alignment, there are six: one in the...

The creation of topographical maps and charts from a stereographic record produced through the overlapping of consecutive...

The law expressing the condition under which a crystal will reflect a beam of x-rays with the greatest amount of distinction...

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

A camera designed to form a continuous record of an expansive section of the horizon. The typical panoramic camera is...

A laser-pumped crystal with nonlinear optical properties inside of an optical resonator in which the output generates...

Chemical vapor deposition is a process of applying dopants to a glass bait by flame reactions of gaseous compounds. See also...

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

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

A lens assembly made up of three lens elements that may or may not be cemented.

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

A linear image sensor is a type of solid-state electronic device used to capture and convert light into electrical signals....

That part of an infrared detector-Dewar assembly that limits the solid angle viewed by the sensor; it is maintained at a...

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials...

A type of internal photonic connection in an integrated circuit in which a holographic grating is used to focus light at...

A small television tube originally developed for closed-circuit television. It is about 1 inch in diameter and 5 inches...

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

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

The separation of unpolarized light into two plane-polarized elements by a doubly refracting crystal. When a crystal, such...

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

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

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

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

An aperture located at an image plane of an optical system that determines the size and shape of the image.

Device which measures the index of refraction of glass as well as the dispersion over visible range.

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

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

A lens that has one convex surface and the other concave.

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

Thin-film coatings are layers of material applied to the surface of an object or substrate, typically to modify its optical,...

In optics, "mode beating" refers to an interference phenomenon that can occur in laser systems with multiple longitudinal...

An infrared light source is a device that emits light in the infrared spectrum, which lies beyond the visible spectrum of...

An aberration that remains after primary color is corrected. Primary color causes the back focus of a lens to vary with...

A dielectric sphere with an index of refraction that varies with distance from the sphere center. A parallel beam of rays is...

A gas, such as oxygen, that improves the speed and efficiency of a laser cutter or welder when applied to the work surface,...

A cell filled with a transparent material that, when placed in a strong electrical field, exhibits double refraction. Since...

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

A laser diode module is a compact device that incorporates a laser diode, optics, and often other components into a single...

An arc discharge tube having a grid that is used to start the discharge through an atmosphere of inert gas or vapor at low...

A colorimeter using a spinning disc made of different colored sections for colorimetric analysis.

Photoelastic equipment and supplies refer to instruments and materials used in photoelasticity, a technique used to analyze...

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

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

Laser optics refers to a broad category of optical components and systems designed for manipulating and controlling laser...

Autofluorescence refers to the natural emission of fluorescence exhibited by certain biological structures or molecules when...

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

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

A polarizing prism consisting of two calcite prisms cemented such that they deviate the two emerging beams (which are...

A concave mirror that has the form of a paraboloid of revolution. The paraboloidal mirror may have only a portion of a...

The condition in which there are more atomic systems in the upper of two energy levels than in the lower, so stimulated...

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...

A polarizing beamsplitting prism similar in design to the Rochon prism. However, the Senarmont transmits the extraordinary...

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

Designating any instrument in which both eyes can be used to view the image to achieve a stereoscopic effect, or merely to...

A negative lens used to increase the effective focal length of a telescope objective.

Optical cements and adhesives are specialized materials used in the assembly and bonding of optical components in optical...

A scintillation crystal, also known simply as a scintillator, is a material that emits light when it interacts with ionizing...

An optical system of variable focal length, the focal plane remaining in a fixed position. This result is achieved by moving...

A Fresnel lens is a type of optical lens that consists of a series of concentric grooves or steps carved into a flat, thin...

A scanning probe microscope that analyzes the surface of a specimen by recording the intensity of light as it is focused...

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

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

An X-Y electrically addressable series of arrays with individual electron emitters bombarding a phosphor-coated transparent...

An APD detector, or avalanche photodiode detector, is a type of photodetector used to detect light or optical signals by...

A method for characterizing a fiber wherein an optical pulse is transmitted through the fiber, and the resulting light...

The smallest angle through which light is bent by an optical element or system. In a prism, the angle of deviation is a...

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

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

A lens aberration that causes a flat object surface to be imaged onto a curved surface rather than a plane.

A compound prism formed by cementing together two 30° prisms, one of right-handed and one of left-handed quartz. It has...

Raman spectroscopy is a technique used in analytical chemistry and physics to study vibrational, rotational, and other...

A type of surface-emitting laser diode that uses dielectric mirrors to produce surface emission. The laser cavity is...

Displacement in a direction perpendicular to that of the intended displacement, as in a translation stage with simple...

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

A confocal resonator, also known as a confocal cavity or confocal laser resonator, is a type of optical resonator...

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

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

The physical length of the light path in a substance divided by the refractive index of that substance. See also equivalent...

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

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

An assembly of multiple prisms that disperses incident light into its spectral components without deviating light at the...

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

Thin-film deposition equipment refers to machinery and tools used in the process of depositing thin layers of material onto...

In the context of thin film deposition processes such as evaporation or sputtering, masks are used to selectively deposit...

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

The incident ray, the normal to the refracting surface at the point of incidence of the ray at the surface, and the...

An astronomical mirror, also known as a telescope mirror or primary mirror, is a key component of a reflecting telescope. It...

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

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

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

Solid-state laser geometry in which the standard rod is replaced by a slab of laser material. Often called...

A polygonal mirror, also known as a multifaceted mirror or facet mirror, is a type of optical component used in various...

State typically studied in liquid crystals in which the dielectric coefficient parallel to the director is less than the...

A molecule that has the ability to chemically combine with other molecules to form a polymer, hence being capable of being...

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

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

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

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

A semiconductor laser diode that emits light perpendicular to the active region. The output radiation is taken through the...

Concave and convex spherical mirrors are types of curved mirrors that have surfaces shaped like segments of spheres. These...

Sapphire crystal refers to a transparent, single-crystal form of aluminum oxide (Al2O3) known as corundum. It is one of the...

A solar simulator is a device used to replicate the spectrum and intensity of sunlight in a controlled environment for...

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

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

An optical system that superimposes a synthetic display providing navigational or weapon-aiming information on a pilot's or...

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

1. Attribute of a visual sensation that permits a judgment to be made of the amount of pure chromatic color present. 2. The...

The unit solid angle subtended at the center of a sphere by an area on its surface equivalent to the square of the radius;...

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

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

The range of frequencies over which a particular instrument is designed to function within specified limits. See also fiber...

An ocular having two planoconvex lenses that are formed from similar glass and that are separated by a space equal to half...

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

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

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

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

Optical manufacturing tools and machinery encompass a wide range of equipment, instruments, and systems used in the...

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

An instrument for determining the temperature of a hot object by examining the color spectrum of the visible light it gives...

A strip or annulus of glass coated with a semitransparent material such as inconel. The coating thickness, and as a result...

When a lens system with a circular aperture is free of aberrations, the image of a point object will appear as a disc of...

Also known as roof prism. A type of prism designed by G.B. Amici. It consists of a roof edge produced upon the long...

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

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

A diverging lens is a type of lens that causes parallel rays of light to spread out or diverge. It is thinner in the center...

Cemented prisms of differing refractive indices which refract incident light and, due to differing refractive indices, will...

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

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

In a fiber optic cable, the longitudinal length required for the transmission media, wrapped around a central member, to...

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the...

A system incorporated into fiber optic data communications characterized by several spatially distributed terminals that are...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic...

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

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

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

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

Also known as radiation thermometer. A pyrometer in which the radiant intensity from the source to be measured is used to...

A photodiode detector is a semiconductor device that converts light into an electrical current. It operates based on the...

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

In the context of optics and lasers, a transverse mode refers to a specific spatial pattern of the electric field within the...

An InGaAs (indium gallium arsenide) camera is a type of imaging device that utilizes InGaAs sensors to capture images in the...

The adjustable membrane located just in front of the crystalline lens within the eye. The iris gives the eye its color. See...

Two plane mirrors that are not wholly located in the same plane. When light from a point source or slit reflects from the...

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...

A device used to measure the intensity of radiant energy.

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

A diffraction grating is an optical component consisting of a surface with a periodic structure of equally spaced, parallel...

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

The method by which Thomas Young in 1802 disproved Newton's corpuscular theory of light by the formation of interference...

An electro-optic modulator (EOM) is a device used to modulate the amplitude, phase, or polarization of light waves using an...

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

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

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

A machine vision lens is a specialized optical lens designed for use in machine vision systems, which are used for automated...

The axes of symmetry in a crystal structure. See also biaxial crystal; uniaxial crystal.

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

A measurement technique used to determine the spatial distribution profile of an electrical or optical quantity of interest...

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

A photovoltaic cell, commonly known as a solar cell, is a semiconductor device that directly converts light energy into...

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

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

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

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

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of...

Law relating the illuminance (or irradiance) of a surface to the cosine of the angle, q, between the normal to the surface...

Quantum key distribution (QKD) is a method of secure communication that utilizes principles from quantum mechanics to...

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

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

The organ of vision or light sensitivity.

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

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

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

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

Azimuthal polarization refers to a specific polarization state of light where the electric field vector of the...

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial...

When light is transmitted through matter, part of the light is scattered in random directions. A small part of the scattered...

An electronic transducer, either fixed or adjustable, that reduces the amplitude of a wave without causing significant...

MTF analysis/measurement equipment refers to instruments and tools used to measure and analyze the modulation transfer...

The circle that contains the slit, grating and primary astigmatic focus of a concave diffraction grating.

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

A molded lens is an optical lens manufactured using a molding process, typically involving the shaping of a material, such...

The letter form used on visual performance test charts. The overall letter height is equal to five times the thickness of...

A charge-coupled device (CCD) is a type of electronic image sensor used in various imaging devices, including digital...

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

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

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

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

The electron beam tube of a television camera that converts an optical image into a pattern of electrostatic charges and...

Sparkling granular pattern that is observed when an object diffusely reflects coincident laser light. Speckle appears as an...

Quantum entanglement is a phenomenon in quantum mechanics where two or more particles become correlated to such an extent...

Holmium lasers are a type of medical laser that utilizes holmium-doped crystals as the gain medium. The term holmium laser...

A source of light will not cast a distinct shadow of an interfering, opaque object, but will cast a shadow having two parts:...

A type of geometrical distortion that brings about a trapezoidal display of a nominally rectangular picture. Usually...

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

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

Phase matching is a crucial concept in the field of optics, particularly in nonlinear optics and the generation of coherent...

A telescope lens is a primary optical component of a telescope system that gathers and focuses light to form an image. It is...

A fiber optic sensor is a device that uses optical fibers to detect and measure physical, chemical, biological, or...

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

Photonics contract manufacturing refers to the outsourcing of the production of photonics-related components, devices, or...

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

Single-mode fiber that preserves the plane of polarization of the light launched into it as the beam propagates through its...

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

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

A five-sided prism containing two reflecting surfaces at 45° to each other, and two refracting faces perpendicular to...

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

A lock-in amplifier is a specialized electronic instrument used to extract and measure small signals embedded in noise or...

A reflecting prism that is rhomboidal in shape. It has two parallel transmitting faces, and two parallel reflecting faces;...

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

A ring laser gyroscope (RLG) is a type of gyroscope that uses laser light to detect and measure changes in orientation. It...

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

The Foucault test is performed by moving a knife edge laterally into the image of a small point source. The eye, or a...

A telescope with a concave paraboloidal objective mirror and a small plane (diagonal) mirror that reflects rays from the...

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

A sapphire window refers to a transparent optical component made from sapphire crystal. Sapphire is a single-crystal form of...

Sapphire optical fiber is a type of optical fiber made from single-crystal sapphire, which is a form of aluminum oxide...

In a visual optical system, the axial distance from the last mechanical surface of the eyepiece to the exit pupil.

An antireflection coating (AR coating) is a thin film or coating applied to optical surfaces, such as lenses or windows, to...

A system used for gratings that consists of a concave mirror, a grating and a plate holder mounted normal to the grating to...

Ultraviolet reflectance refers to the ability of a material or surface to reflect UV light. Ultraviolet light is...

1. In a cathode-ray tube, the glow surrounding a bright spot that appears on the fluorescent screen as the result of the...

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

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

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

The range of angle or solid angle values by which light may enter an optical system.

A microscope designed with two eyepieces (oculars), permitting the use of both eyes when viewing through the instrument.

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

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical...

The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at...

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

A colorimeter is a device used to measure and quantify the color characteristics of an object or a light source. It provides...

Optical design and engineering services involve the development, customization, and optimization of optical systems and...

A microchannel plate (MCP) is a specialized electron multiplier device used in various applications such as particle...

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

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

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

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

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

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

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

A GaAlAs laser is a type of semiconductor laser diode that emits light in the near-infrared region of the electromagnetic...

The process whereby white light is separated into its component wavelengths. Light beams of different wavelengths are...

A small instrument containing a picture support and a pair of magnifying lenses so arranged that the left eye sees only the...

A form of liquid crystal with an appearance of moving, threadlike structures, particularly visible when observed in thick...

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

An optical instrument containing a gimballed sighting telescope, used to measure angular relationships in horizontal and...

The central peak (including everything interior to the first zero or dark ring) of the focal diffraction pattern of a...

Also called sine wave response and contrast transfer function. The modulation transfer function is the ratio of the...

The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The...

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

Vision at intermediate levels of luminance between photopic and scotopic vision, where both retinal cones and retinal rods...

A dichroic coating, also known as a dichroic filter or dichroic mirror, is an optical coating designed to selectively...

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

A measure of the relative difference in refractive index between two optical materials. Most commonly used in fiber optics...

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

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

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

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

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

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

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

The creation of a planned sequence of data input that is obtained while airborne for use in aerial photogrammetry and other...

A mirror blank refers to the initial piece of material from which a mirror is made. It is typically a flat or slightly...

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

The angle formed between a refracted ray and the normal to the surface. This angle lies in a common plane with the angle of...

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

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

A diode laser is a type of laser that uses a semiconductor diode as the active medium to generate coherent light....

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

A fiber laser is a type of laser in which the active gain medium is an optical fiber doped with rare-earth ions such as...

A Ti:sapphire laser is a type of solid-state laser that utilizes a titanium-doped sapphire crystal as the gain medium. The...

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

A microscope that uses a flying spot scanner, directed through the eyepiece, as a light source to determine the features of...

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

The efficiency of scattering by an atom in a particular direction, expressed as: where AA is the amplitude of the wave from...

A high-speed, narrow-field lens consisting of two achromats spaced about the aperture stop. Its uses include portrait...

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

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

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

CID, or charge injection device, camera refers to a type of imaging device that utilizes a specific kind of solid-state...

A system in which a supplied signal causes the deflection of the electron beam in a cathode-ray tube, thus forming a visible...

An alexandrite laser is a solid-state laser that utilizes a synthetic crystal made from the rare earth element alexandrite...

A prism invented by William Nicol in 1828 that is made of calcite, the end faces of which are ground to an angle of 68°...

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

A chart on paper or glass containing a series of sets of lines at progressively smaller spacing and used to ascertain the...

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

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

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

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

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

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

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

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

Light consisting of a single wavelength or a very narrow band of wavelengths.

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

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

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

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

As a wavefront of light passes by an opaque edge or through an opening, secondary weaker wavefronts are generated,...

Also known as Fresnel reflection. That portion of the incident radiation that is reflected from the surface of a refractive...

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

An intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an...

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

A nanotube, also known as a nanotubule or simply a tube-like structure, is a nanoscale cylindrical structure composed of...

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

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

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

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

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

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

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or...

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

The law given by the formula: that is, the frequency of radiation emitted or absorbed by a system when E2 and E1...

Literally, neodymium:yttrium-aluminum-garnet. A cylindrical rod of yttrium-aluminum-garnet doped with neodymium that is the...

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

A device consisting of a microammeter, a photovoltaic cell and a battery. It is used for the measurement of scene brightness...

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

A fiber optic bundle split along its length with the ends of the fibers extending separately to illuminate different points...

1. A device used to trace out an object and build up an image. One of the most common of these types is video scanning. The...

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

The apparent difference in brightness between light and dark areas of an image. For a light target against a dark...

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

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

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a...

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

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

An instrument that measures several optical parameters, such as optical power and wavelength, with a single measurement...

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

A laser having a material, such as ruby, that has an energy state structure of three levels: the ground state (1) wherein...

A magnon is a quasiparticle representing a quantized spin wave in a magnetic material. In other words, it is a collective...

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

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

A common aberration in lenses covering large fields of view; it results in images of objects near the edge of the field...

Epitaxial refers to the growth of a crystalline layer on a crystalline substrate in such a way that the orientation of the...

A fast, wide-angle lens used in television and photographic cameras, with excellent overall correction, but subject to...

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

An aspheric mirror is an optical mirror surface that deviates from the shape of a perfect sphere, having a non-spherical...

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

Instruments used by ophthalmologists and optometrists to study the eye. There are, for instance, the ophthalmoscope to...

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

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

Of all the rays passing through a lens from an off-axis object point to its corresponding image point, there is always one...

A camera designed to record at rates exceeding 50 fps. For frame rates up to about 500 fps, an ordinary pull-down mechanism...

A physical constraint, often a lens retainer, that limits the diameter of the axial light bundle allowed to pass through a...

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

Dichroism refers to the property of certain materials to exhibit different colors or absorbance of light depending on the...

Optical fiber is a thin, flexible, transparent strand or filament made of glass or plastic used for transmitting light...

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

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

Rare-earth elements (REEs) are a group of seventeen chemical elements found in the Earth's crust, characterized by their...

An eyepiece consisting of a planoconvex field lens and a cemented doublet as the eye lens.

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

An eyepiece located at the near end of the microscope tube. It often is a simple Huygens eyepiece, but compensating and...

A form of roof prism used to invert an image. The prism has faces cut normal to the optical axis; therefore, the prism may...

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

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

In an optical system, the gradual reduction of image illuminance as the off-axis angle increases, resulting from limitations...

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

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

A CCD image sensor, or charge-coupled device image sensor, is a type of electronic device used to convert optical images...

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

1. An eyepiece or magnifier with a scale at its image plane. That scale is placed in contact with an object, permitting...

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

Gain-switching is a technique used in lasers to generate short pulses of light by modulating the gain of the laser medium....

Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in...

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

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible...

Time-correlated single photon counting (TCSPC) is a technique used in photon counting applications, particularly in the...

A terahertz spectrometer is a scientific instrument used to measure and analyze the properties of materials in the terahertz...

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

A CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and...

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

A process of color photography in which colors are added one to another in the form of light, rather than as colorants, to...

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

An imaging technique used in radiology that is based on the principles of nuclear magnetic resonance (NMR) to produce...

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

Plastic optical fiber (POF) is a type of optical fiber made from transparent plastic, typically polymethylmethacrylate...

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape...

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

Off-axis paraboloid and ellipsoid mirrors are specialized optical components used in various optical systems, particularly...