Photonics Dictionary: E

Technique for the precision evaluation of coincidence of a laser beam's center with the edge of the object under study and exact location of that edge by means of a double electronic differentiation...

A transistor designed to respond to either light or electrical signals.

A panel of photoconductive and electroluminescent layers used as either a positive or negative image intensifier, depending on amplitude and phase of its two power supply voltages. The...

Conduction of an electric current through a chemical compound in its natural state, solution or as a molten, to decompose the compound.

The freeing of electrons from an electrode into the surrounding space.

An analytical technique used to determine the nature of extremely small samples by forming the x-ray spectrum of the samples through excitation by a finely focused electron beam.

The movement of particles or ions in a solution toward the electrode having the opposite sign because of the application of an electrical field.

A technique that uses the passage of an electrical current through a recording medium to produce a permanent image on that medium.

Embedded vision refers to the integration of computer vision technologies into various embedded systems, devices, or machines. Computer vision involves teaching machines to interpret and understand...

The line or lines emitted by an element when its radiation particles travel from one energy level to another.

A type of electron microscope in which the specimen also serves as the cathode source.

Thermal emission caused by the unity in absorption bands that must be discriminated when calculating radiation intensity of any celestial object.

Emission spectroscopy is a technique used to study the emission of electromagnetic radiation (light) by atoms, molecules, or ions when they undergo transitions from excited states to lower energy...

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light emitted by a source, such as an atom, molecule, or celestial object. It shows...

The emissivity of a body times the emissive power of a blackbody at the same temperature. For a blackbody, it is the total radiation per unit area of radiating surface.

The ratio of an object's radiance to that emitted by a blackbody radiator at the same temperature and at the same wavelength.

A computer-generated routine for achieving true-temperature readings in thermal infrared imaging systems.

In photography, the layer of light-sensitive material (usually a suspension of silver halide crystals) that coats the film or plate.

The sensitivity of a photographic emulsion when exposed to light, provided that the film is developed through a standard process.

The energy in a medium per unit volume.

A type of laser pulsing with high laser power at the beginning of the pulse.

Epitaxial deposition is a process used in semiconductor manufacturing and materials science to grow a thin crystalline layer, known as an epitaxial layer, on a substrate. The term epitaxial refers to...

A densitometer having a receiver that indicates when a desired radiation level has been attained.

1. A contour map of a photographic deposit consisting of lines and curves that join points of equal density. 2. The portrayal of a photograph's points of equal density in hues of yellow, cyan and...

1. The use of an electronic microdensitometer to measure points of equal density on a photographic deposit. 2. A technique that simplifies a picture's density pattern by making a single isodensity...

In image processing, a morphology operator in which a structuring element or probe of a particular shape is moved over the input image. Where the probe fits completely within the boundaries of a...

The light spectrum formed by an explosive reaction or by the electrical explosion of a metallic wire by a strong current.

In cosmology, a star that exhibits a rapid increase in the magnitude of light, which is followed by a slow decrease in magnitude. The nova and supernova are explosive variables.

A photodetector composed of a semiconductor material whose responsive properties can be altered by the addition of impurities to the basic material. Copper- and mercury-doped germanium are both...

A type of optical fiber loss resulting from the misalignment of fibers in a splice or connector.

Synonym of extrinsic fiber loss.

Photoconductivity due to the addition of impurities or external causes.

The properties exhibited by a semiconductor as the result of its modification by imperfections and impurities in the crystal.

An event-based image sensor, also known as a dynamic vision sensor (DVS), is a type of digital imaging device designed to capture visual information in a highly efficient and unique way compared to...

Observed phenomenon of a small developed image with higher density than a larger image because of variation in photographic plate densities with variations in size of opening.

A lens mounting with eccentric rings that may be rotated to shift the axis of the lens to a prescribed position.

A grating that serves to provide higher resolution and dispersion than the average grating, and still has a greater free spectral range than either the Fabry-Perot etalon or the reflection echelon.

A specialized form of diffraction grating consisting of assembled glass plates of equal thickness that resemble a flight of stairs. The light enters through the largest plate at the end and emerges...

Edge AI, also known as edge artificial intelligence, refers to the deployment of artificial intelligence (AI) algorithms and models directly on edge devices, such as smartphones, sensors, IoT...

In image processing, the location of edges by employing templates that respond to the first or second derivative of gray-scale intensity in the neighborhood of each pixel.

In image processing, any operation that strengthens information about the edges of objects displayed. Three types of spatial filtering are used: shift and difference, gradient and Laplacian.

In image processing, a segmentation algorithm for isolating a region in an image by following its edge.

Intensity distribution in the image of an edge. The gradient of the edge-response curve is a measure of the image quality of the optical system under test.

Process for growth of solar cells that results in rectangular shapes consisting of many interconnected cells in a series or series-parallel arrangement. EFG cells show increased efficiency with...

An edge-emitting light-emitting diode is a type of LED structure where light emission occurs primarily along the edge of the semiconductor chip rather than from the surface. Edge-emitting LEDs are...