Photonics Dictionary

Pertaining to the possession of photoelectric characteristics as a result of the properties of the true crystal and not of foreign materials.

A photometric instrument used to measure the illumination falling on a surface. It may be photoelectric or visual.

An image intensifier, also known as an image intensification tube or image intensification device, is a specialized electronic device used to amplify low-light-level images to make them visible to...

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible spectrum of light. These detectors are utilized in various applications,...

Any of the photoelectric and thermal detectors, spectrographs and monochromators, thermographs, scanners, amplifier tubes, snooperscopes and related equipment developed for use with infrared...

Any device that is used to sense and measure light. See exposure meter; photoelectric exposure meter; photoelectric photometer; reflected light meter.

The decrease in the energy of a photoelectric emission as a result of the simultaneous incidence of radiation having lower frequency than that forming the emission.

A transistor that uses an electro-luminescent source, a transparent base and a photoelectric collector.

A device that uses a photoelectric cell to determine the level of oxygenation in the blood.

The responsivity of a photocathode to luminous energy equal to the ratio of the photoelectric emission to the incident luminous flux.

Photocathodes are specialized materials or surfaces that exhibit the photoelectric effect, wherein the absorption of photons leads to the emission of electrons. When photons with sufficient energy...

A photodetector, also known as a photosensor or photodiode, is a device that detects and converts light into an electrical signal. Photodetectors are widely used in various applications, ranging from...

A photodiode detector is a semiconductor device that converts light into an electrical current. It operates based on the principle of the photoelectric effect, where photons of light incident on the...

Electron released in photoelectric activity.

A photometer that uses a photoemissive tube to detect and measure light. See photoelectric photometry.

A photomultiplier tube (PMT) is a highly sensitive vacuum tube that detects and amplifies low levels of light. It is widely used in various applications where high sensitivity, fast response times,...

A document-transmitting process that uses a cylinder that rotates the document to be scanned and detected by a photoelectric cell. The cell transforms the light into electrical energy that may be...

An electron tube having a photocathode for the emission of a photoelectric current.

A photoelectrical relay that uses a phototube as its photoelectric device to open and close an electrical relay; used to activate counters and safety controls.

The area of optics in which quantum theory is used to describe light in discrete units or "quanta" of energy known as photons. First observed by Albert Einstein's photoelectric effect, this particle...

A device composed of a light source and phototube used to scan a moving strip of material in photoelectric side-register control systems.

A photocathode that receives radiation from one side and emits a photoelectric current from the opposite side.

The angle at which photoelectric sensors are aligned to prevent light from being reflected back to the sensor from the object during retroreflective sensing; also, the angle a measured part is...

An automatic scanning instrument that is used to study a substance's fluorescence over a wide range of wavelengths. It consists of a radiation source, a grating that functions as the monochromator in...

An instrument consisting essentially of a photoelectric cell filtered to respond to a specified wavelength region, an amplifier of sufficient gain to provide power enough to control movement of a...

A traveling wave tube (TWT) containing a photocathode and window that, receiving a laser beam, produces a modified photoelectric current that is accelerated and propagated into its helical frame.