Photonics Dictionary: A

The transition cross section constant coefficient which defines the transition probability of absorption from ground to a higher level within a given atomic or molecular species. The transition...

An absorption peak refers to a sharp increase or spike in the absorption of electromagnetic radiation at a particular wavelength or energy level. It is a distinctive feature in the absorption...

Impurity in a semiconductor or any other electroluminescent device capable of inducing hole conduction and accepting a valence band electron to produce an acceptor energy level.

The present radiation level within a laser or electromagnetic radiation operating area.

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...

Agri-photonics refers to the application of photonics technologies in agriculture. Photonics involves the generation, manipulation, and detection of light and other forms of radiant energy whose...

A category of systems designed to communicate a photo taken from the air (e.g., aircraft, balloon, satellite) to a ground station. It can be done by direct television transmission of the photo, or by...

A type of fiber optic sensor that detects alteration in position, distance, pressure, liquid level or temperature by transmitting light across a gap to a reflector; a change in the light returned to...

An optical system with different focal lengths or magnification levels in perpendicular planes to the optical axis.

An aplanatic surface is an optical surface that is specifically designed or shaped to minimize spherical aberration and coma. Spherical aberration is an optical aberration that occurs when light rays...

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial objects for observation and analysis. It typically consists of two main optical...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical elements in a sample by measuring the absorption of light at...

An atomic clock is a highly precise timekeeping device that uses the vibrations or oscillations of atoms as a reference for measuring time. The most common type of atomic clock uses the vibrations of...

Any system of time measurement that is based on atomic resonances. The transition times between the hyperfine levels of cesium-133 have been accepted as the international standard.

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...

Attosecond photonics sources refer to devices or systems that generate extremely short pulses of light on the order of attoseconds (1 attosecond = 10-18 seconds). These ultrafast light pulses are in...

Augmented reality (AR) is a technology that integrates digital information, typically in the form of computer-generated graphics, images, or data, with the real-world environment in real-time. AR...

A device that utilizes avalanche multiplication of photocurrent by means of hole-electrons created by absorbed photons. When the device's reverse-bias voltage nears breakdown level, the hole-electron...