A reticle, also known as a reticule or graticule, is a pattern or set of markings placed in the focal plane of an optical instrument, such as a microscope, telescope, riflescope, or camera, to provide a reference point or aid in measurement or...

Having properties resembling those of light- waves; e.g., the propagation of waves in the television spectrum.

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

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

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...

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

With respect to television, a potentiometer that allows variation of the intensity of the different elements of an image and...

A device that provides means for accurately moving minuscule tools over the surface of a microscopic object. The motion...

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

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

A type of glass used in telescope mirrors, formed by adding a nucleating agent to standard glass and then heating it until...

With respect to television, the returning direction of the electron beam during the vertical blanking period.

A tabulation of predicted positions that have been calculated for one or more celestial bodies or orbiting satellites.

A technique for obtaining improved resolution of images produced by large telescopes and distorted by the effects of...

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

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

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

Concave is an adjective used to describe a surface or shape that curves inward or has a hollow or recessed appearance. In...

A dark band that may appear in the field of crossed Nicol prisms with a powerful source such as the sun because the light is...

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

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

Quantum dot light-emitting diode (QLED) is a display technology that utilizes quantum dots, which are semiconductor...

To transform a picture or image field into a television signal for transmission.

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...

1. A method of photographing distant objects with a lens of long focal length. 2. The reproduction of photographs over a...

Modification of a system to provide for a linear transfer characteristic from an input to an output device. A circuit for...

The graph of the oscillating variations composing the wave of a video signal.

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

An instrument used to record the emittance or reflectance of an object by scanning with discrete spectral resolution over a...

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

Any material of a macromolecular nature that can stretch at room temperature to more than twice its length and return to...

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

Also known as display primaries. Colors formed by a television receiver that are of constant chromaticity and variable...

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

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

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

Any optical transmission channel used in telecommunications designed to connect two end terminals or to be connected in...

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

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

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

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

The light from a nonselective diffuse reflector due to the standard illumination of the scene to be televised.

An infrared imaging device composed of a detector array and readout electronics. It may include a cryogenic cooling system....

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

Although low in sensitivity (approximately 10-7 m for helium-neon lasers), this holographic technique permits quantitative...

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

A sheet of thin brass, one edge of which has been accurately cut to a known and marked circular radius. It is used to check...

In an interlaced scanning electro-optical system such as television, the system resolution will be less than the number of...

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

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

Second-order nonlinear optical properties refer to a class of phenomena exhibited by certain materials in response to...

A television system that does not broadcast television signals but transmits them over a closed circuit.

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

A contraction of quasi stellar. An astronomical object that appears to be a star but has a different, larger redshift.

A corrective lens system that is placed near the focal plane of a Newtonian telescope to increase its effective field of...

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

Optical coatings are thin layers of materials applied to optical components, such as lenses, mirrors, filters, and prisms,...

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

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

A reflection grating is an optical component that consists of a series of closely spaced, parallel reflecting surfaces or...

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

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

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

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

The value equal to the raster height divided by the half-period of a periodic test pattern.

1. A stereoscope that has adjustable scales to allow the determination of distances and dimensions from stereoscopic...

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

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

Videography refers to the process of capturing moving images and recording them in a digital format. It involves the use of...

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

A large telescope mirror fabricated from several smaller sections.

Two stars so close together that they cannot be resolved by telescopes. They are proved to be double stars by the doubling...

A television display system in which the television signal is converted to an image that is projected onto either a front or...

A type of receiver that uses a local oscillator at a frequency deliberately offset from that of the incoming signal. It is...

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

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

A telescope that produces an erect image. Erection is achieved either by a lens (for a long instrument) or a prism (for a...

Gamma ray radiation released when matter and antimatter, such as electron and positron, unite and eliminate each other,...

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

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

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

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

A Peltier cooler, also known as a thermoelectric cooler (TEC) or thermoelectric module, is a solid-state device that uses...

A camera accurately aligned to a weapons system to provide a photographic record of system performance.

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

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

Descriptive of an optical fiber having a core refractive index that decreases almost parabolically and radially outward...

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

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light...

An unbounded quantity, an indefinitely large number. Infinity is commonly expressed by the symbol ∞.

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

A camera capable of making successive exposures on a continuous film driven by accurately spaced sprocket holes (a motion...

An image-forming system having curved mirrors in place of transparent glass components. Mirror lenses are commonly used for...

Also called scanning laser acoustic microscope. A device that uses high-frequency ultrasound waves to penetrate surfaces. A...

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

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

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

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

A color-television viewing system with three kinescopes, three lenses and three deflection yokes used to form the red, green...

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

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

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

To control, by magnifying or reducing, the size of a televised image, either electronically or optically.

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

Technology that corrects the shape of reflective optics; primarily applied in large telescope systems, in order to...

A crystalline substance in which all planes are parallel, or approximately parallel.

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

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

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

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

A camera equipped with angular scales in altitude and azimuth. The scale readings are imprinted on the film when an exposure...

The subtractive imbibing process of transferring color prints on paper whereby the dyes from three separately prepared...

The angular subtense of the field of view in the image space of a telescope, as differentiated from that in the object space...

A telephoto lens form noted for its lack of distortion.

1. The sector of the Earth's surface registered upon a remote sensing device in a satellite. 2. The amount of space occupied...

The material favored for study of interaction of high-acoustic intensities with free carriers. Tellurium is the...

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

A defect of a binocular instrument causing two images to be seen separately instead of being fused. It is caused when the...

The superposition of satellite or aerial images with a map in order to process and remove distortion. Uses reference points...

In a reflecting telescope, the obstruction of the primary mirror by a secondary mirror which blocks a small amount of the...

A controlled motion system that may use a telescope, camera or antenna to follow accurately a satellite, missile, vehicle or...

A type of birefringent polarizing prism that transmits the extraordinary ray and removes the ordinary ray through total...

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

In television, the number of individual pixels that can be distinguished in a horizontal scanning line; also called...

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

A microcomb, short for microresonator frequency comb, is a novel photonic device that generates a precise series of evenly...

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

An instrument for measuring the vertical angle of an object. It usually contains an accurately made protractor, a sensitive...

A polycrystalline material that transmits in the infrared; it is used as a phosphor in x-ray and television screens.

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

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

A scanning technique in which the object is illuminated the entire time, and in which picture elements of the object are...

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 type of comparator with a telescope equipped with a cross wire mounted on a vertical sliding column. It is used to measure...

The point spread function (PSF) is a fundamental concept in imaging that describes the response of an imaging system to a...

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

The approximately concentric waves that form on a surface that has been polished without an oscillation of the polishing lap.

An old name for the rotating arm moving about an axis of rotation over a divided circle used to measure angles. Now the term...

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

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

Raster scanning process like that of television: each line is scanned successively.

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

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

With respect to television, the transmission of the signals that originate from variously colored parts of an image in a...

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

A cathode-ray tube that serves as a picture tube in a television receiver. The signal representing the picture intensity is...

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

An imaging system designed to highlight small deviations in a planar reflective object such as a mirror. The system can be...

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

The method by which photographic film is scanned by an electron beam. One technique uses the uniform light of a television...

A device, such as a thermionic or crystal diode, that is introduced into the vision channel of a television receiver to...

Two oppositely charged particles.

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

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

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

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

The study of the celestial bodies, relative to x-ray emission. Satellites launched to study x-ray sources have revealed many...

In television, the period during which the electron beam is cut off while the raster returns from the right-hand side of the...

Device in which the various circuit elements are fabricated in different substrate materials and then appropriately joined...

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

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

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

A small erect-image telescope for use as a sighting device on a rifle. The chief requirement is a long eye relief to avoid...

The observation of a reproduced television picture on the face of a cathode-ray tube.

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

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

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

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

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

A technique used in astronomy that requires a radio telescope to be directed at a point in the sky west of the object under...

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

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

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

A coupling unit that enables more than one transmitter to operate at the same time or separately on the same antenna.

The fiber optic connector standard for Nippon Telephone & Telegraph (NTT) installations, developed with Nippon Electric...

the photography of very close, and typically small objects with a magnification of approximately 1:1

A telescope so manufactured that the image remains erect and the position of the eyepiece is unchanged as the line of sight...

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

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

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

1. A term used to describe the clouded appearance of an incompletely polished surface that scatters light. 2. The...

A document-transmitting process that uses a cylinder that rotates the document to be scanned and detected by a photoelectric...

The process by which a surface is made to conform accurately to a given curvature.

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

The angle subtended by the mean distance of the Earth from the sun at the distance of a given star from the sun.

Consists of a pair of radio telescopes concentrated on a single celestial object. This technique creates a single radio...

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

An enclosure whose walls are coated to absorb completely all radiation striking them.

An optical filter is a device that selectively transmits or blocks specific wavelengths, or colors, of light. Optical...

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

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

A device used to transmit and receive images that have been converted to electrical signals over regular telephone lines; it...

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

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

An inspection device in which the profile of a mechanical part is projected onto a ground-glass screen at a precisely known...

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

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

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

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

Decrease in cosmic ray activity that is observed approximately 24 hours after a solar flare, attributed to a shielding...

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

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

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

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

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

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

Biometrics refers to the automated recognition of individuals based on their physiological or behavioral characteristics....

Dispersion refers to the phenomenon where different wavelengths (colors) of light travel at different speeds when passing...

A loss of resolution or detail in a television signal caused by the size of the electron scanning beam.

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

A dispersion-shifted fiber (DSF) refers to a type of optical fiber designed to minimize the effects of chromatic dispersion,...

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

In semiconductor physics and materials science, the term "III-V materials" refers to compounds composed of elements from...

Indium phosphide (InP) is a compound semiconductor material composed of indium (In) and phosphorus (P). It belongs to the...

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

A mirror mount is a mechanical device used to secure and precisely position mirrors in optical systems. Mirrors are...

The process of using a spectrograph with a telescope to acquire information on an astronomical object's speed and physical...

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

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

The capability of the spatial distributions of incident and reflected flux to interchange completely without alteration of...

Ray tracing is a rendering technique used in computer graphics to simulate the way light interacts with objects in a scene....

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

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

An optical tooling instrument consisting of an objective lens, a focusing lens, an optical micrometer, a reticle and an...

A device for the internal inspection of hard-to-get-at mechanical parts, such as rifle barrels, sewer pipes, oil wells, or...

The ratio between the focal length of a lens having a longer focal length than that of the standard lens used with a camera,...

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

Diffraction efficiency is a measure of how effectively a diffractive optical element (DOE) or diffraction grating directs...

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

A process used in document copying and printing that involves the visible rendering of an invisible electrostatic image on a...

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

A telescope that uses a reflecting objective to focus an image of a distant object at a focal point.

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures changes in hemoglobin...

In an optical waveguide, a ray that is completely confined to the core.

A device that completely or partially restricts the amount of light reaching the eye.

A term used to describe a photograph, film or television picture where the values for black and white areas are at or near...

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

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

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

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

1. The term used to describe any of the many instruments used to remotely record physical dimensions, such as strain,...

The state of a carrier signal that corresponds to maximum picture brightness in a television system.

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

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

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

An optical gate typically refers to a device or system that controls the transmission of light, allowing it to pass through...

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

A simple form of astronomical telescope that uses a fixed objective and a focusable eyepiece. The objective forms an...

Nonlinear optics is a branch of optics that studies the optical phenomena that occur when intense light interacts with a...

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

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

A man-made satellite that orbits 35,680 km from the Earth at a rate of one orbit per 24-hour period, thereby retaining its...

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

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

1. A prism used in some instruments to bend light 90° before it enters the objective. 2. A dispersing prism located in...

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

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

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...

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

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

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

Positioning generally refers to the determination or identification of the location or placement of an object, person, or...

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

A method of taking radiographs at a distance from the object being photographed to decrease distortion.

A television camera tube that preceded the development of the vidicon tube and incorporated a method to separate reflected...

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

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

A coarse diffraction grating that is used to form a scale of intensities to determine the relative magnitudes of stars. The...

A broadband filter is an electronic or electromagnetic device designed to pass a range of frequencies or signals within a...

A semiconductor platelet laser that emits a coherent image by means of plane optical pumping over the platelet surface, and...

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

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

In a remote sensing system, nadir refers to the point on the ground located vertically below the center of the system. In...

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

Characterizes an Earth-orbiting satellite whose orbit plane is near polar and positioned at an altitude that allows it to...

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

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

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

A telemicroscope in which a negative eyepiece is used to produce erect images.

A visual system including a tiny television tube and imaging optics, all contained in a helmet to be worn by pilots in...

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

Etaloning is an optical phenomenon that occurs in imaging systems, particularly in devices such as spectrometers,...

A small telescope mounted on a tripod and free to rotate about a vertical axis. A spirit level is mounted over the telescope...

A microscopic crystal found in an intricately crystallized substance that is only visible under a microscope.

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

A telescope that transmits, enlarges and converts infrared images.

A handheld navigational instrument used to measure the elevation angle of celestial bodies such as the sun. An image of the...

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

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

The unit generally used to express distances within the solar system, and sometimes to measure interstellar distances....

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

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

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

A positioning slide mechanism with two rows of alternately crisscrossed cylindrical rollers.

A telescope that corrects dispersion and spherical aberration through the use of one or more lenses, usually smaller than...

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

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

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

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

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

The number of times per second that the frame of a television system is completely scanned. In the United States, 30 per...

The apparent luminosity or glow that immediately envelops the cathode in a gas-discharge tube operating at low pressures....

The gas of charged particles that begins approximately 50 km above the surface of the Earth and contains a sufficient...

In microscopy, the chamber that is contained on a microscope slide to hold a certain amount of fluid. It is calibrated...

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

A wedge in a rangefinder or heightfinder used to displace the image produced by one telescope so that it coincides with that...

A telescopic eyepiece comprising five or six simple lenses in the form of three doublets or two doublets and a singlet.

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

A system consisting of two or more Geiger-Müller counters, connected in coincidence with their centers on an axis. The only...

An instrument that serves to produce an enlarged electron image on a fluorescent screen by focusing an infrared image of a...

In a telephoto lens, the ratio of the overall length to the focal length of the lens. It is generally about 0.8 to 0.9 in...

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

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

A phase screen, in the context of optics and wave optics, refers to a surface or medium that introduces a phase delay to an...

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

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

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

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

A television format with enhanced vertical resolution (400 lines as compared with the standard 330) that, unlike...

A term referring to the cathode-ray tube used in television receivers.

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

A plane mirror mounted on a polar axis that lies parallel to the plane of the mirror. When the mirror is rotated once in 48...

In the context of electronics and optics, an isolator refers to a device that allows the transmission of signals in one...

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

A telescope that is fixed or has a limited degree of movement in a vertical plane; primarily used to determine the position...

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

Diamond turning, also known as diamond machining or diamond cutting, is a precision machining process used to produce...

An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot onboard. UAVs are remotely...

The science of sensing and measuring information at some remote location and transmitting the data to a convenient location...

A television system in which the images produced appear three-dimensional.

Short wavelength infrared (SWIR) refers to the portion of the infrared spectrum that encompasses wavelengths roughly between...

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

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

1. A framelike structure that serves to restrict the viewing area of the screen when placed before a television picture...

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

Terahertz (THz) refers to a unit of frequency in the electromagnetic spectrum, denoting waves with frequencies between 0.1...

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

Phase distortion refers to a change in the phase relationships between different frequency components of a signal. In the...

Opsins are a group of light-sensitive proteins found primarily in the retinas of vertebrate and invertebrate eyes, as well...

The code used to describe the United States system of color telecasting.

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

A telescope similar to the customary Cassegrain telescope, but having a primary mirror that is ellipsoidal and a secondary...

In interlaced television scanning, an effect in which the lines of one field fail to fall exactly within the lines of the...

A technique developed by British Telecom in which the viscous drag of air is used to install optical fibers in narrow...

The nondestructive analysis and recording of industrial components based on the absorption of relatively low-energy neutrons...

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

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

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

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

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

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

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

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

A nonhomogeneity of index in flat glass that is in the form of an approximately plane layer.

An afocal optical device made up of lenses or mirrors, usually with a magnification greater than unity, that renders distant...

A computing paradigm that attempts to process information in a manner similar to that of the brain; it differs from...

An optical instrument used to track and image a test vehicle (target) throughout its flight. The cinesextant frequently...

Abbreviation of "synchronization.'' In television, the timing signals used to drive the scanning process. Horizontal...

A fluorescent screen refers to a phosphorescent or fluorescent-coated surface that emits visible light when exposed to other...

A flat, round micrometer that is placed in the focal plane of a telescope to measure difference in right ascension and...

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

A kinescope used to survey the details of television video transmission.

The utilization of photometric measurement to determine the relative magnitudes of the heavenly bodies.

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

MWIR stands for mid-wave infrared, referring to a specific range of wavelengths within the infrared spectrum. Infrared...

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...

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

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

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

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

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

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

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

An event-based image sensor, also known as a dynamic vision sensor (DVS), is a type of digital imaging device designed to...

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

A diffraction pattern sampling unit composed of a 32-element monolithic silicon photodiode array and a readout unit. The...

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

A particle that will not normally diffuse through animal or vegetable membrane. Larger than most inorganic compounds,...

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

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

A telescopic system having an eyepiece, a reticle and an objective. The instrument measures wavefront power in diopters.

Referring to the bandwidth and spectrum location of the signal produced by television or radar scanning.

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

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

Machine vision lighting refers to the use of specific lighting techniques and equipment in the field of machine vision,...

A measure of the total light passed by a shutter during an exposure, compared with the light that could be passed by an...

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

A spectrophotometer that measures the amount of ozone in the atmosphere through a comparison of solar energy at two...

A form of Cassegrain telescope having a concave hyperbolic primary and a convex hyperbolic secondary. This form permits the...

The time domain is a concept used in signal processing and analysis to describe signals in terms of their behavior over...

A technique used in photolithography of computer chips to compensate for errors caused by the proximity effect, which...

The principles and techniques involved in the use of telephotometers to measure atmospheric extinction.

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

Remote inspection refers to the process of inspecting, evaluating, or monitoring assets, equipment, infrastructure, or...

An accurately produced hole of any size and shape that is used as a masking device in an optical system. Pinhole apertures...

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

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

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

The law stating that the critical fusion frequency is approximately proportional to the logarithm of the luminance and the...

A telescope that is mounted on an equatorial mount.

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

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

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

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

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

A passive infrared system that uses two line-of-sight telescopes to generate both narrow and wide field-of-view images of...

A device that controls the output of a television receiver's horizontal oscillator.

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

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

Polarization refers to the orientation of oscillations in a transverse wave, such as light waves, radio waves, or other...

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

Retroreflection is a phenomenon in optics where light is reflected back toward its source, typically in a direction nearly...

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

In field-sequential color television, the rotating tricolor disc placed between the subject and the lens, or between the...

A telescopic eyepiece that produces a field of view between 40° and 50°. The eyepiece consists of a single element...

A unique glass made up of nano-structured materials to create millimeter sized monolithic glass space-variant polarization...

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

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

The position and shape of the image of a point source, as predicted by geometric optics alone. The geometric image is to be...

A device used to lock the internal synchronization generator of a television camera to an external source.

Any systemic process that ultimately reassembles all the system's components into their initial alignment, or an arrangement...

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

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

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

An acronym for communications intelligence, referring to the collection of communications signals in the VHF and UHF...

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

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

A metalens, short for "metasurface lens," is a type of optical lens that uses nanostructured materials to manipulate light...

In optics and photolithography, a phase mask refers to a device that modifies the phase of light waves passing through it....

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

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

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

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

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

Any form of lens, optical system (camera, telescope, microscope, etc.), or opto-electronics utilized for the purpose of...

A sensing or image-forming detector that serves to convert infrared rays into visible signals for communication purposes....

Freeform optics refers to the design and fabrication of optical surfaces that do not follow traditional symmetric shapes,...

A direct-readout television pickup tube.

That portion of the telecommunications network that runs from a local central telephone to the subscriber premises.

The span of frequencies within which a single channel of broadcast television must fall; in the US, it is 6 MHz.

Nanopositioning refers to the precise and controlled movement or manipulation of objects or components at the nanometer...

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

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

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

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

An airspaced achromatic doublet telescope objective.

A technique for measuring the concentration of any gases. Identical infrared beams are alternately chopped, one passing...

An electron tube that is used as a camera tube for a television system. When the picture to be transmitted is focused on a...

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

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

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

The field of view (FOV) refers to the extent of the observable world or the visible area that can be seen at any given...

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

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

In astronomy, the method of deliberately viewing objects with peripheral vision to take advantage of the eye's greater...

An aplanatic surface is an optical surface that is specifically designed or shaped to minimize spherical aberration and...

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

The term "metaverse" refers to a collective virtual shared space, created by the convergence of virtually enhanced physical...

A discipline that combines optics and genetics to enable the use of light to stimulate and control cells in living tissue,...

A numerical value representing the degree of contrast in a television picture: the exponent of the power law used to...

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

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

A spatial light modulator (SLM) is an optical device that modulates or manipulates the amplitude, phase, or polarization of...

A television camera tube in which a low-velocity electron beam scans a photoactive mosaic that has been created by an...

A device designed to enlarge the image of a microscopic object by television process. It may be a flying spot scanner that...

The term that represents the size of one of the many small elements into which a television image is necessarily broken down...

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

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

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

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

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

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

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

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

A two-flux theory in which the radiation is assumed to be composed of two oppositely directed radiation fluxes through a...

1. A measure of absorbed dose, equal to the energy imparted by ionizing radiation to a mass of matter corresponding to 1 J...

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

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

A Cassegrain telescope having a parabolic primary mirror, a spherical secondary mirror and a zero-power doublet in the...

Photographing of terrain on the ground and objects in the air by cameras mounted in aircraft; utilized in satellites,...

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

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

An adhesive used to affix optical elements to an approximately shaped body -- usually of cast iron.

A constant equal to the universal gas constant divided by the Avogadro number. It is approximately equal to 1.38 x 10-23 J/K...

An instrument designed to collect naturally formed extraterrestrial electromagnetic radiation within the radio frequency...

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

A camera containing an electronic image sensor that converts the image to an electronic signal suitable for television...

A molecular motor refers to a nano-sized device composed of organic molecules or other small-scale components that can...

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

An image that is not immediately recognizable but scrambled.

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

The angular width of a radiation beam. With respect to a conical beam of light, it is the vertex angle of the cone. The...

A point source of light used for the test and evaluation of image quality. May be a backlit pinhole in an otherwise opaque...

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

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

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

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

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

Instruments used for measuring angles and occasionally lengths on the ground. The principal surveying instruments are the...

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

A type of telescope mount that permits direct azimuth and elevation adjustments.

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

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

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

A pixel, short for "picture element," is the smallest controllable element of a digital image or display. It is a...

A large table with an accurately designed plane surface used to test other surfaces, or to provide a true surface for...

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

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

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

An infrared device used in satellites and rockets to determine a heat horizon for the Earth at altitudes (above 200 miles)...

LiFi, short for light fidelity, is a wireless communication technology that utilizes visible light or infrared light to...

Sharp and narrow absorption lines found in the spectra of stars. They result from the absorption of a part of a star's...

An ideal body that completely absorbs all radiant energy striking it and, therefore, appears perfectly black at all...

A handheld binocular telescope that is commonly of the Galilean type.

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

Any problem that requires retrieval of the distribution of some internal properties, such as temperature concentration,...

An artificial star used to aid in adaptive optics imaging of the sky. The guide star is provided from a telescope system on...

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

Chalcogenide refers to a class of compounds containing elements from group 16 of the periodic table, which includes sulfur...

An image-forming system that uses mirrors rather than lenses. Such objectives are frequently used for astronomical...

The frequency range for radio and television transmission.

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

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

1. A constituent part. It may consist of two or more parts cemented together, or with near and approximately matching...