Type

Browse by Letter

PI Physik Instrumente - 50 ways hexapod ROS MR 7/24

Meadowlark Optics - Wave Plates 6/24 MR 2024

7,024 terms

Photonics Dictionary

Clear All Filters x fs x
photoelectromotive force

The force that stimulates the emission of an electrical current when photovoltaic action creates a potential difference between two points.

photoelectron holography

A technique proposed for studying the atomic structure of crystals by measuring the interference pattern generated when the crystal is illuminated by a burst of finely tuned x-rays. The resulting...

photoelectron microscopy

Surface analysis by means of photon induced electron emission. PEM methods provide high lateral resolution of the observed sample.For surface material sciences PEM allows the investigation of...

photoemission -> photoelectric emission

The electron emission from a substance or instrument whose surface has been bombarded by a suitable amount of radiation.

photoemissive cell -> photoemissive detector

An electronic tube instrument in which the anode current varies with the intensity of light incident on the cathode.

photoemissive detector

An electronic tube instrument in which the anode current varies with the intensity of light incident on the cathode.

photoemissive effect -> photoelectric effect

The emission of an electron from a surface that occurs when a photon impinges upon the surface and is absorbed. This effect is the means by which photons may be detected.

photofabrication

The use of photoetching techniques to produce small tools, parts and dies from sheet metal.

photoglow tube

A particular type of phototube having increased sensitivity as a result of the glow initiated by light incident to the cathode.

photogrammetric equipment

The special cameras, film and other means for forming maps by aerial photography.

photogrammetry

Photogrammetry is a technique used to obtain accurate three-dimensional measurements of objects and environments through the analysis of photographs or imagery. It involves extracting information...

photographic dosimetry

The use of photographic emulsions to detect and determine the amounts of ionizing radiation, such as x-rays and gamma rays, in an area. This is accomplished by exposing the emulsion to the radiation...

photographic exposure

The product of exposure time and irradiance or illuminance.

photographic field

The maximum angle of view that can be recorded by a camera. Field is a function of lens focal length and film format.

photographic photometry

A form of photometric measurement, often used with light sources that are transparent or fluctuating, in which a photographic plate is used to obtain a record of a source's relative intensities over...

photographic radiometry

The use of photographic recording equipment to measure radiant energy. With this procedure, many measurements of radiant energy can be recorded simultaneously and permanently.

photographic resolution

A measure of the ability of a photographic system to record fine detail. Usually stated in terms of cycles per millimeter on the processed film.

photographic sensitometer -> sensitometer

An instrument for determining the sensitivity of a photographic film to light. The film is given either a stepped exposure or a continuously varied exposure; after processing, the density is measured...

photographic sensitometry

The measurement of the responsivity of photographic media and of the relations between exposure and density of developed images.

photographic shutter efficiency

A measure of the total light passed by a shutter during an exposure, compared with the light that could be passed by an idealized, infinitely fast shutter fully open for the same extreme time.

photographic sound recorder

A system in which the electrical signal embedded within an audio input signal is converted to a modulated light pattern and recorded on film.

photographic thermometry

The photographic recording of the heat radiation emitted from various points on the object as corresponding density variations on fast infrared film.

photoimmunotherapy

Photoimmunotherapy (PIT) is a medical treatment approach that combines elements of phototherapy and immunotherapy to target and treat specific cells or tissues in the body. The key components of this...

photoionization

The ionization that occurs in gas affected by the action of radiation quanta.

photoisolator -> optoisolator

An optical coupling device that uses light to bridge the gap between incompatible wire communications systems. It contains an input amplifier, a light-emitting diode, a photodiode and an output...

photolithography

Photolithography is a key process in the manufacturing of semiconductor devices, integrated circuits, and microelectromechanical systems (MEMS). It is a photomechanical process used to transfer...

photoluminescence mapping

A technique used for noncontact inspection of semiconductor wafers. The material is illuminated by an excitation source that stimulates photoluminescence; the resulting spectrum is analyzed, yielding...

photoluminescence

Photoluminescence is a phenomenon in which a material absorbs photons (light) at one wavelength and then re-emits photons at a longer wavelength. This process occurs when electrons in the material...

photolysis

The photochemical reaction of light present in the decomposition of a substance.

photolysis flash -> spectroscopic flash

The light flash, produced in flash photolysis, that is triggered within a second discharge tube by the third electrode. It is to be differentiated from the photolysis flash which is triggered within...

photomacrography -> macrophotography

the photography of very close, and typically small objects with a magnification of approximately 1:1

photomagnetic effect

The direct influence of light on the magnetic susceptibility of particular materials.

photomask

A photomask, also known simply as a mask or reticle, is a key component in the photolithography process used in semiconductor manufacturing and other areas of microfabrication. It is a high-precision...

photometer

A device used to compare the luminous intensities of two sources by comparing the illuminance they produce.

photometric

Pertaining to the measurement of the intensity of light.

photometric cube

A prism used in a photometer for the adjacent comparison of separate luminance.

photometric equipment

Photocells of various kinds used to measure photometric quantities; i.e., intensity, luminance and illuminance. Meter readings are used to express illuminance and, by calibration, to measure...

photometric filter -> color conversion filter

A filter that serves to alter the color temperature and the mired value of the radiation emitted by a source.

photometric sphere -> integrating sphere

A hollow sphere coated internally with a white diffusing material and provided with openings for incident beam, specimen and detector used for measuring the diffuse reflectance or transmittance of...

photometry

Photometry is the branch of science that deals with the measurement of light, particularly in terms of its intensity and the way the human eye perceives it. It involves the quantification of visible...

photomicrograph

A photomicrograph is an image taken through a microscope, typically using a camera attached to the microscope's eyepiece or an integrated digital imaging system. It captures the magnified view of...

photomicrographic camera

A still or motion-picture camera designed to photograph through a microscope. Photomicrographic equipment usually contains a beamsplitter or other means for simultaneously viewing, orienting and...

photomicrography

The use of a microscope in photographing objects. A device for photomicrography includes a light source, microscope and camera mounted on a rigid base.

photomorphogenesis

The study of the effects of light on the growth and development of various plants.

photomultiplier tube

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,...

photon

A quantum of electromagnetic energy of a single mode; i.e., a single wavelength, direction and polarization. As a unit of energy, each photon equals hn, h being Planck's constant and n, the frequency...

photon burst detection of fluorescence

A type of laser spectroscopy used to measure short-lived isotopes by observing sudden bursts of fluorescence resulting from repetitive excitation of an atom or molecule.

photon correlation spectroscopy

Spectroscopy used to study the concentration, diffusion and Brownian motion of small particles suspended in a fluid by measuring dynamic fluctuations of light that is scattered or fluoresced by the...

photon counter

A device used to evaluate the luminance of a surface by determining the number of photons emitted from a sample surface area.

photon coupling

The coupling of two circuits by the use of a light pipe through which photons are transmitted.

Photonics Dictionary

Need Help?