Photonics Dictionary

Any of a series of radioactive elements with atomic numbers ranging from 89 to 103.

The creation of a chemical reaction in a substance when radiation is directed to it.

The study of chemical changes produced by radiation.

A device that measures the intensity of photochemically active radiation, particularly from the sun. One form of this instrument determines the fluorescence initiated by the radiation.

Component that is externally controlled via electronic or photon signal.

imaging system which clearly shows the IR signals in the field of view as well as ambient environment

That layer in a semiconductor injection laser or light-emitting diode that provides optical gain.

A material that produces stimulated emission during the process of amplification with a laser system.

Technology that corrects the shape of reflective optics; primarily applied in large telescope systems, in order to compensate for slowly varying changes in temperature, wind and mechanical stress.

The layer of material in a laser diode from which the optical radiation is emitted; light producing region

The transport of molecules in a cell which requires the use of a cell's internal energy. The energy used in the cell may be ATP as a primary transport or an electrochemical gradient give as the...

A type of liquid-crystal display in which each display element contains an active component, such as a thin-film transistor, to maintain its state between refresh scans.

When applied to LCD grids, the active matrix is a means of supplying power to pixels by use of a transistor and capacitor. The transistor functions with leads in operation with its respective row and...

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two thin-film transistors (TFTs) to control the on-current at each OLED cell or...

An OLED display that has an integrated electronic backplane as its substrate. Active-matrix OLED displays use at least two thin-film transistors (TFTs) to control the on-current at each OLED cell or...

1. Synonymous with radioactivity. The intensity of a radioactive source illustrated as the number of atoms disintegrating in unit time, or as the number of scintillations or other effects observed...

Mechanical device intended for the translation (rotational and linear) using high precision control from electronically operated circuits. See linear actuator; rotary actuator.

In photography, the density gradient across an edge separating light from darkness, a physically measurable quantity that correlates well with subjectively observed sharpness of definition. By...

In biaxial crystals, the principal angle that bisects the smaller angle between the optic axes.

Spontaneous changes to the visual system making it more or less sensitive to light.

1. In optics, the housing, usually cylindrical, that contains the lenses and iris diaphragm of a camera. 2. In fiber optics, a device for coupling two connectors.

The process of adjusting input pixel by pixel at the filter plane to adapt to nondeal phase behavior in an optical correlator.

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of atmospheric distortions. The Earth's atmosphere can cause light passing through it...

An apparatus used to determine the degree of adaptation of the eye under different conditions.

Process in which two or more lights are combined by superposition.

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

Additive manufacturing (AM), also known as 3D printing, is a manufacturing process that involves creating three-dimensional objects by adding material layer by layer. This is in contrast to...

The luminance of a mixture of lights is the sum of the luminances of the component lights in the mixture.

The code signifying the location of the information being sought on a CD-ROM.

In display technology, an expression of resolution given by the number of pixels in both the horizontal and the vertical axes of a cathode-ray tube or similar device.

The intermolecular attraction between two surfaces, as between a substrate and a coating; it is an important factor in the durability of optical thin films.

An intermolecular substance that serves to hold materials together. Two types are used in the optical industry: one, which must be transparent and colorless, to cement lenses together; and a...

Method for studying absorption coefficients of low-loss materials, in which a sample is allowed to come to thermal equilibrium with its surrounding blackened enclosure. The sample is irradiated with...

A process during which no heat enters or leaves the system.

With respect to photography, the change in the density-exposure relations, for small details of the photographic image, that is noted when compared with the density-exposure relations for large...

The process by which a substance, usually a solid, attracts and retains on its surface the molecules of another substance.

A chemical placed in a solution that will indicate when an excess of a substance or ion has been reached by coloring the precipitate after the chemical itself has been totally adsorbed.

A television format with enhanced vertical resolution (400 lines as compared with the standard 330) that, unlike high-definition television, can operate on existing bandwidths and with existing...

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...

An accelerator at the Argonne National Laboratory, providing powerful x-ray beams for materials research applications.

An aerial reconnaissance system that can transmit, in near real time, image data recorded by IR and visual-spectrum sensors, providing day, night and foul-weather intelligence.