Photonics Dictionary

Advanced driver assistance systems (ADAS) refers to a set of safety features and technologies designed to assist drivers in the driving process and enhance overall vehicle safety. These systems use...

The use of photographs -- motion picture or still -- to establish if a particular event exists.

A device that prevents electrons from a saturated pixel in a CCD imaging device from spilling into an adjacent pixel. The antiblooming gate drains a pixel of any charge in excess of its full-well...

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

An arc flash is a sudden release of electrical energy due to an electric arc — a continuous, high-current discharge of electricity between conductors or from a conductor to ground. Arc flashes...

An attenuator is an electronic or optical device used to reduce the power or intensity of a signal without significantly affecting its waveform or other characteristics. Attenuators are commonly used...

In optics, a collapsible structure situated between the lens and film of a camera to allow variation of the distance between them while preventing surrounding light from exposing the film.

The use of a short-duration electron beam to record high-speed events that occur in microscopic objects made of materials that emit visible fluorescence during electron bombardment. The method is...

A chamfer ground on the edge of a lens or prism. Bevels are used to prevent chipping or to achieve a mechanical fit.

A calcium indicator is a molecule that is sensitive to changes in calcium ion (Ca2+) concentrations in biological systems. These indicators are commonly used in various fields, including cell...

A light-tight box that receives light from an object or scene and focuses it to form an image on a light-sensitive material or a detector. The camera generally contains a lens of variable aperture...

Carbonization is a process in which organic materials are heated in the absence of air, leading to the decomposition of the material and the production of carbon-rich residue. During carbonization,...

The darkening of the laser facet of a semiconductor laser diode. It can be prevented by placing the component in a hermetically sealed enclosure.

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

Chirped pulse amplification (CPA) is a technique used in laser physics to amplify ultrashort laser pulses to high energies without causing damage to the amplifying medium. The method was first...

A passive device, having three or more ports, in which input light from one port is coupled only to the next sequential port in a given direction and is prevented from traveling in any other...

A defect in an optical system that prevents rays from reaching their intended destination; it can be caused by an undersized aperture, a baffle out of position, etc. In imaging applications, removing...

Electronic circuit capable of distinguishing the pulses emitted by separate counters in a given time phase and determining whether the pulses were emitted by the same particle or correspond to a...

A coverslip, also known as a cover glass or cover slip, is a thin and flat piece of transparent material typically made of glass or plastic. It is used in microscopy to cover a specimen mounted on a...

A sudden, brief increase in current or voltage in a circuit that can damage sensitive components and instruments. Preventive measures include slow-starter circuits, filtering and static control.

Deep ultraviolet (DUV or deep-UV) refers to a specific range of ultraviolet light with shorter wavelengths than those in the UV-A and UV-B regions. The exact wavelength range considered as DUV can...

A CCD device for sensing longer wavelengths, such as NIR and IR, that has a deeper depletion region than would be necessary for sensing in the visible wavelength range. Because the depth of charge...

A digital twin refers to a virtual representation or digital counterpart of a physical object, system, or process. This digital replica is created using real-time data and simulation models, allowing...

A piece of glass that eventually becomes the bifocal segment as it appears prior to being fused to the blank.

Double-clad fiber (DCF) is a specialized optical fiber that features two concentric cladding layers surrounding a core. The design of double-clad fibers allows them to be used in various...

A type of streak camera that uses film wrapped around a drum, which moves at a constant speed to record the changing shape of a short-lived event, such as a lightning flash.

An electron-gun system is an assembly used to generate and control a focused beam of electrons. Electron guns find applications in various fields, including cathode ray tubes (CRTs), electron...

A laser or laser system positioned within an enclosure to prevent dangerous optical radiation from leaving the enclosure.

An enzyme-linked immunosorbent assay (ELISA) is a laboratory technique used to detect and measure the presence of specific substances, such as antibodies, antigens, proteins, hormones, or other...

Epitaxial equipment refers to a set of specialized tools and systems used in the process of epitaxy, which is the growth of crystalline layers on a substrate material. Epitaxial growth is a critical...

An event-based image sensor, also known as a dynamic vision sensor (DVS), is a type of digital imaging device designed to capture visual information in a highly efficient and unique way compared to...

Excimer laser coronary angioplasty (ELCA) refers to a medical procedure used in the treatment of coronary artery disease. This technique involves the use of an excimer laser to perform angioplasty, a...

A small incandescent lamp whose intense beam is focused on the optical soundtrack of a motion picture film. The soundtrack modulates the beam, which in turn is detected by a photocell that produces...

Wavelengths between 400 and 1400 nm (VIS to NIR) are focused onto the retina by the cornea. Because the retina is sensitive to light, these wavelengths can be damaging even at low energies. It is the...

A fiber optic cable assembly refers to a complete unit consisting of optical fibers, connectors, protective jackets, and other components that are assembled together to facilitate the transmission of...

A fiber optic preform is a cylindrical glass rod or tube used as the starting material for manufacturing optical fibers. It serves as the precursor from which optical fibers are drawn. The process of...

Filoviruses are a family of viruses that are responsible for severe and often fatal hemorrhagic fevers in humans and non-human primates. The name "filovirus" is derived from their filamentous...

A material that surrounds a fiber optic cable's buffer tubes to prevent moisture from entering if the jacket is breached.

A high-speed cine camera that produces discrete frames of a continuous event as opposed to the flow photographic record of a streak camera.

Free-space optics (FSO), also known as optical wireless communication or optical wireless networking, refers to the transmission of data using modulated beams of light through free space (air or a...

The length of the small space within which the atmosphere exhibits coherence, particularly in relation to an observer on Earth viewing celestial objects. The turbulence of the Earth's atmosphere...

Germicidal ultraviolet (GUV) refers to a specific range of UV radiation that has disinfectant properties capable of killing or inactivating microorganisms, including bacteria, viruses, and fungi. The...

Ink used for writing on glass, and also for blackening the edges of lenses to prevent reflection. In the latter case, the refractive index of the ink must closely match that of the glass.

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a tungsten filament surrounded by a small amount of halogen gas, such as...

A cloud chamber designed to maintain the gas within it at a high pressure as a means of reducing the range of the high-energy particles and, subsequently, increasing the chances of observing...

The holographic recording of sequences of high-speed phenomena. With a multiple beam laser, multiple holograms that depict rapid events can be formed on a single medium.

A high-speed motion camera, also known as a high-speed camera or slow-motion camera, is a specialized imaging device designed to capture fast-moving events or phenomena at extremely high frame rates....

Photography involving the recording of events that occur too fast to be perceived by the human eye or recorded by conventional photographic techniques. See high-speed movie camera; high-speed...