Photonics Dictionary: C

The binding of gas to a surface or in matter by chemical activity.

The transmission of a color photograph by separating the colors into varying intensities of red, blue and green, and then sending separate transmissions of the three color signals to a receiving...

A mercury vapor discharge lamp that has cadmium added to emit radiation in the red region as a complement to the mercury vapor's blue and green radiation.

The three lines in the spectrum of cadmium that have the purest radiations and that were first used by Michelson to calculate the standard meter.

The narrowest line of the cadmium spectrum; the red line has the purest radiation.

An inorganic compound, yellow to orange in color, that fluoresces strongly enough when bombarded by a high-current-density electron beam to be used as a high-intensity light source.

A photoconductive cell having cadmium sulfide as its photoconducting material for the production of a very high dark-light resistance ratio.

A doubly refracting mineral used to produce polarizing prisms. It is uniaxial negative and in the trigonal division of the hexagonal system of crystals. Its indices are e = 1.486, w = 1.658; its...

A microscope that allows examination of a small crystal and conveniently provides linearly polarized object and reference beams so that, by suitable orientation of an anisotropic crystal, the optical...

An optical material used in place of crown glass to produce lenses with extraordinary correction of chromatic aberrations. Its high coefficient of thermal expansion and its tendency to absorb...

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...

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

An optical wedge in which transmittance or density is a function of the location of the wedge, relative to a specific optical system.

Any known value derived from standard analysis that serves as a reference to the accuracy of an instrument or process in determining one or more variables.

An instrument used to measure the change of heat content of a system by measuring microwave power in terms of generated heat.

Calorimetry is a branch of science that involves the measurement of heat flow in physical or chemical processes. It encompasses various techniques and instruments used to quantify heat transfer,...

The term sometimes used to describe the sequential arrangement of components in a video system -- from transmitter to receiver.

Camera Link HS (high speed) is a standard developed for high-speed digital data transmission in machine vision and industrial imaging applications. It is an evolution of the original Camera Link...

A portable instrument that uses a four-sided reflecting prism or set of mirrors to create a duplicate image of an object on a horizontal sheet, on which outlines of the subject may be traced by hand.

The use of the photographic process to produce precision copies of an original image that are many times smaller in size. One of its many applications is in microcircuitry.

The electron beam tube of a television camera that converts an optical image into a pattern of electrostatic charges and then scans the pattern to produce a corresponding electronic signal for...

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...

SI unit of luminous intensity. It is defined as one sixtieth the normal intensity of one square centimeter of a blackbody at the solidification temperature of platinum. A point source of one candela...

The luminous intensity of a source of light expressed in candelas.

The luminescence of an incandescent material.

A gas laser in which the energy-state transitions between vibrational and rotational states of CO2 molecules give emission at long IR, about 10 µm, wavelengths. The laser can maintain...

In analysis, the carbon layer that is evaporation-deposited on a specimen to protect and ready it for study by electron microscopy.

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,...

A system that generally uses a photodetector to decode punched cards for information, or for input to a computer, by sensing the light transmitted through the punched holes.

An oil immersion condenser used to permit only light that has been diffracted or dispersed by a microscope specimen to enter the microscope. It is used in dark-field microscopy.

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor material. Semiconductors are materials with electrical conductivity between...

The ratio of the power of the carrier wave to that of unwanted signal distortions, or noise, before any nonlinear signal processing such as detection or amplitude limiting.

A heterochromatic photometric process using successive comparison of similar chromaticities and the calculation of relative luminances of unlike chromaticities as the product of ratios of luminances...

A shower of cosmic rays whereby a high-energy electron produces one or more photons that convert into electron pairs, the secondary electrons producing the same effects as the primary. As the process...

The Casimir force is a quantum phenomenon that results in an attractive force between two closely spaced uncharged conductive surfaces. This force arises from the quantum vacuum fluctuations of the...

A two-mirror lens design used in astronomical telescopes, the primary being a parabola, the secondary a smaller hyperbola. The image formed is free of spherical aberration and color and is located...

A system that uses both reflection and refraction to achieve its focal power. While the relative powers of the lenses and mirrors vary from system to system, the use of the reflective surfaces to...

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

The area of low-level luminance lying between the cathode and the negative glow in a glow-discharge, cold-cathode tube.

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

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the form of light, into an electrical signal. Photocathodes are components used in...

Also known as cathode rays. Formerly, this term described a stream of electrons emitted from the cathode of a gas-discharge tube during its bombardment by positive ions. It also describes any stream...

The luminous trace formed on the cathode-ray tube screen by the motion of the electron beam.

A vacuum tube with an electron gun at one end and a fluorescent screen at the other. Electrons emitted from a heated filament are accelerated by a series of annular anodes at progressively higher...