Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in temperature. In other words, it is the production and emission of light by a material or substance, often as a result of...

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

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

Hyperspectral imaging is an advanced imaging technique that captures and processes information from across the...

A device that enables visual tracing of a fiber optic cable to check for breaks and defects by coupling visible light into...

A common technique in microscopy, oblique illumination is one in which the object is illuminated by a light source that is...

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

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

Radiation consisting of more than a single wavelength in the visible region of the spectrum.

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

The process of producing a visible two-dimensional image of a scene that is dependent on differences in thermal or infrared...

An infrared source combined with reflecting projection optics to illuminate a target making it visible when observed through...

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

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

The amount by which an optical surface deviates from its ideal design value, expressed in wavelengths of light. Optical...

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

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

Photosynthetically active radiation (PAR) is the 400- to 700-nm region (visible light) of the electromagnetic spectrum that...

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

That region of the electromagnetic spectrum to which the retina is sensitive and by which the eye sees. It extends from...

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

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

The study and photographing of microscope specimens in ultraviolet light; using an optical microscope containing fluorite...

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

A mirror with a coating that reflects infrared radiation and transmits visible light.

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

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

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

The reflection in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

The smallest area of uniform brightness that can be seen by the eye. It is measured in terms of the solid angle subtended by...

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

A plane in which an image is formed. A real image formed by a positive lens would be visible upon a screen located in this...

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

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

The term photochemical pertains to chemical processes or reactions that are initiated or influenced by the absorption of...

A light source that emits an uneven distribution of radiant energy through the visible range.

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

A panel of photoconductive and electroluminescent layers used as either a positive or negative image intensifier, depending...

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

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

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

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

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

An electrophoretic display, often referred to as an electronic paper display or e-paper display, is a type of electronic...

A solid-state panel of the photoconductor-electroluminescent type. The photoconductive layer, sensitive to x-rays, is coated...

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

A device consisting of a disc with a spiral arrangement of holes that is used to convert visible patterns into electrical...

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

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

E.I. duPont's trade name for a polyester film. The most practical beamsplitter for use beyond the 15-µm wavelength...

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

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

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

The process by which an atomic system changes from one energy level to another by either the emission or absorption of...

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

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

An image converter that produces a visible image based on the infrared emittance of the object. The infrared energy is...

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

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

A polishing scratch having no visible conchoidal breaking of the edges.

Three filters used in making a color print of a color negative, red, green and blue-violet, respectively. Each filter...

Characteristic of an object so small in size or so fine in structure that it cannot be seen by the unaided eye. A...

A broadband, visible picosecond probe pulse capable of measuring an entire absorption spectrum in one shot.

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

That characteristic which makes a weapon system less visible to radar, optical, acousto-optic, infrared and other military...

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

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

Referred to as SWCNTs, these cylindrical nanostructures composed of a folded sheet of graphene can be used as near-infrared...

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

A type of microscope that uses radiation in the infrared region to illuminate objects that are opaque to visible radiation....

The emission of light by thermal radiation of a temperature high enough to render the source of radiation visible.

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

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

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

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

Diffuse reflectance spectroscopy (DRS) is a nondestructive analytical technique used to investigate the optical properties...

The use of a short-duration electron beam to record high-speed events that occur in microscopic objects made of materials...

A chemical substance that exhibits fluorescence when excited by ultraviolet radiation, x-rays or an electron beam. The...

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

That term pertaining to the spectral region that can be perceived by the eye.

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

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

A laser skin-resurfacing method that creates microscopic thermal wounds referred to as microscopic treatment zones (MTZs),...

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

Transmission in different amounts as a function of wavelength, as a result of absorption and scattering, leading to color...

The property exhibited by a substance having electrical conductivity that decreases as the intensity of the incident visible...

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

Controlled beam technology that introduces beams of sunlight through holes in a roof that are relayed throughout the...

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

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

A glass filter that transmits visible light while absorbing infrared energy (heat).

Ultraviolet (UV) fiber optics refers to optical fibers that are designed and optimized for the transmission of ultraviolet...

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

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

A stationary noise that occurs for visible light photodetection when a steady light source, such as a heterodyne reference...

Structural color refers to coloration in materials that is not caused by pigments or dyes but is instead a result of the...

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

A semiconductor is a type of material that has electrical conductivity between that of a conductor and an insulator. In...

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

The analysis of light in the blue region of the visible spectrum.

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a...

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

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

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

A semiconductor device with the property of conducting current more easily in one direction than the other. It has two...

Any organic substance, that when dissolved in appropriate liquid based solvents will absorb and emit electromagnetic...

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

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

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

Also known as TEA laser. A coherent optical source with a wide wavelength range in the infrared, visible and ultraviolet...

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

A fluorographic method whereby the sensitive photographic medium is pressed against a fluorescent screen to form a visible...

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

The fluorographic method whereby the visible image (as opposed to the x-ray image) is photographed by mounting a camera in...

The inability to perceive visual images (visible radiant energy). In human beings, blindness is defined as a visual acuity...

Usually consists of a set of filters that attenuate specific wavelengths but transmit as much visible radiation as possible.

In a cathode-ray tube, the visible line or lines formed on the screen by the deflection of the electron stream.

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

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

Visible laser radiation, often optically expanded and collimated, used to induced temporary blindness from within a walking...

The light formed by visible radiation that, in traveling from light source to object, undergoes one or more reflections. In...

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

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

Color sensitivity extended to cover the entire visible spectrum out to the red.

A means of determining a prism's index of refraction by placing the prism so that its emergent face is perpendicular to the...

See optical spectrum; visible spectrum.

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

In surface height measurement of optics with steep slopes, the use of two short visible wavelengths to synthesize a longer,...

A coating applied to a neutral density glass that is designed to reduce the amount of light evenly across the transmitted...

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

A term used to denote the condition of a few easily visible coarse inclusions within a blank of glass.

A tube containing mercury vapor and lined with a phosphor. When current is passed through the vapor the strong ultraviolet...

A spectrum band that is usually found in the visible or the ultraviolet because of the electron transitions taking place...

A structure consisting of a thin film of liquid crystal sandwiched between light-polarizing filters that have received a...

Photometry is the branch of science that deals with the measurement of light, particularly in terms of its intensity and the...

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

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

A holographic plate coated by photopolymeric mixtures that are composed of one or more monomers and a photoredox catalyst...

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

A lumen is a unit of measurement used to quantify the amount of luminous flux, which is the perceived power of light. In...

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

In a general sense, any one of a class of instruments used to disperse radiation, visible or invisible, into its component...

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

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

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

Diffuse light emitted by the atmosphere due to the excitation of particles of atmospheric gas. These excited particles...

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

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

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

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

Radiation from the sun that is made up of a very wide range of wavelengths, from the long infrared to the short ultraviolet...

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

Microscopy is a scientific technique that involves the use of microscopes to observe and study objects that are too small to...

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

Phototoxicity refers to the harmful effects caused by exposure to light, particularly intense or ultraviolet (UV) light, on...

A type of compound microscope that uses three visible wavelengths to translate details produced by invisible radiation.

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

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

Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications...

A camera used in scintillation recording to make a visible record of the distribution and relative concentration of...

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

In astronomy, the relation that states that the intensity of a star's visible radiation is inversely proportional to the...

A spectrum that is continuous in the UV region with borders ranging from the visible to 300 A and lower.

A long-pass filter is an optical filter that allows longer wavelengths of light to pass through while blocking or...

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

A filter that transmits infrared and ultraviolet but is opaque to visible radiation.

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

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

The production of visible light by infrared radiation whereby the light is produced by heat and not by any direct change in...

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

A photomicrographic recording technique that utilizes dark-field illumination to render an image of an object having a...

A cathode-ray tube that increases the brightness or size of an image or forms a visible image from invisible radiation. The...

A fluorophore is a molecule or a portion of a molecule that has the ability to emit light upon excitation by an external...

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

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

The pattern of physical or chemical changes that has taken place in a photographic emulsion, by its exposure to light, that...

The rays (such as ultraviolet rays) lying past the visible region of the spectrum.

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

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

A stimulus that contains equal energy at each wavelength in the visible region of the spectrum.

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

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

An image-forming instrument in which a strong electrostatic field causes cold emission of electrons from a sharply rounded...

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

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

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

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

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

A nitrogen vacancy (NV) refers to a specific type of defect or impurity in a crystal lattice where a nitrogen atom replaces...

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

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

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

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

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

Radiation from the invisible (usually ultraviolet) region of the spectrum.

In astronomy, the relative brightness of a celestial body. Originally a scale from 1 to 6, where 1 represented the brightest...

A visible laser beam generated coaxially with an infrared or other invisible laser beam to aid in its positioning.

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

A method of erasable optical data storage in which information is stored by visible light, then read by illumination with an...

A lamp that has mercury in a tube or bulb that has first been evacuated. The electricity travels through the vapor between...

A phosphor, such as sulfide or selenide, that can be excited to luminescence by incident infrared radiation simultaneous to...

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

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

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

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

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