Photonics Dictionary: E

The study of the generation of electromagnetic power by radiation from high-energy beams.

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.

A device that permits only electrons within a narrow velocity range to pass through it, while rejecting those above and below.

A molecule that is the mirror image of another molecule. The two mirror-image molecules have the same chemical properties; their behavior differs only in reactions with other enantiomers or with...

Excimer laser coronary angioplasty (ELCA) refers to a medical procedure used in the treatment of coronary artery disease. This technique involves the use of an excimer laser to perform angioplasty, a...

The ejection of electrons from the surface of a solid by the absorption of a sufficient amount of photons.

A ray that has a nonisotropic speed in a doubly refracting crystal. It does not necessarily obey Snell's law upon refraction at the crystal surface.

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...

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...

1. That portion of the aperture that functions to collect energy and deliver it to the final system detector. 2. For an obscured or noncircular aperture, the equivalent nonobscured, circular aperture.

The color of an object when it is illuminated by a nonisophotic source.

The real numerical aperture (NA) of a fiber when the computed NA is not valid because of change in the glass indices during drawing and fusion.

Three proportional coefficients labeled Am, Bmn, and Bnm, that respectively characterize the rate of spontaneous emission, induced emission, and absorption of radiation by an atom, ion or molecule.

A shift in the direction of the red in the spectral lines of light which, defined by the relativity theory, will have decreased frequencies upon emerging from a highly gravitational field.

Any material of a macromolecular nature that can stretch at room temperature to more than twice its length and return to approximately its original shape when stress is released.

A refracting telescope that uses a prism to bend the line of sight 90°.

An electrically excited laser having carbon monoxide as the lasing material and in which lasing occurs in a partial inversion between adjacent, vibrational fields. Vibrational energy is cycled...

The use of a krypton laser system for the measurement of small molecules aligned by an electric field, by analyzing the absorption of linearly polarized light.

A device that uses four electrodes set in an alternating positive-negative polarity series to focus the beams of charged particles employed in electron microscopes and particle accelerators.

A lamp that uses the transmission of an electric current through a gas or vapor to produce illumination. Neon, mercury and argon lamps are examples of electric-discharge lamps.

A device that detects radiation by utilizing the influence of light in forming an electrical signal. It may be a phototube; a photoconductive, photovoltaic or photojunction cell; a phototransistor;...

The spectroscopic analysis of interference patterns using an electronic imaging tube with a Fabry-Perot interferometer to record the fringes.

An electro-optic modulator (EOM) is a device used to modulate the amplitude, phase, or polarization of light waves using an external electrical signal. Electro-optic modulation is a fundamental...

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

A type of optical modulator with potential application in optical switching and displays, in which applied voltage causes a change of interfacial tension between mercury and an electrolyte, varying...

A device consisting of an airtight quartz tube that holds the material to be analyzed. When a high-frequency electrostatic field, generated by microwaves, is applied to the tube, it emits energy of a...

A technology that uses electrically activated holograms stored within specially developed crystals to route information in the form of lightwave signals from one optical fiber to another within and...

The nonthermal conversion of electrical energy into light in a liquid or solid substance. The photon emission resulting from electron-hole recombination in a PN junction is one example. This is the...

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 ability of a device to operate without electromagnetically interfering with the operation of nearby equipment and without suffering disturbances from the electromagnetic fields in its designated...

Radiation emitted from vibrating charged particles. A combination of oscillating electrical and magnetic fields that propagates through otherwise empty space with the velocity of light. This constant...

An electromagnon is a quasiparticle excitation that combines aspects of both magnetism and electric polarization in a crystal lattice. Specifically, it refers to a collective excitation of spins and...

A maser that relies on the fact that electrons in orbital motion in high-magnetic fields will emit energy at the cyclotron frequency. The transfer of energy is from the bunching of the electrons by...

A cathode-ray tube that increases the brightness or size of an image or forms a visible image from invisible radiation. The focal plane for the optical image is a large, light-sensitive, cold...

That branch of metallurgy that uses electron microscopic techniques in the examination of the nature of metals.

A device utilizing an electron beam for the observation and recording of submicroscopic samples with the aid of photographic emulsions or other short-wavelength sensors. With the electron microscope,...

An EMCCD (electron-multiplying charge-coupled device) camera is a type of scientific camera specifically designed for low-light imaging applications that require high sensitivity and fast readout...

A CCD device in which a solid-state electron multiplying register has been added to the end of the normal serial register. The electron multiplying register allows weak signals to be multiplied...

The control of free electron movement through the use of electrical or magnetic fields, and use of this electron movement in research investigation of electronic diffraction phenomena, directly...

A method for detecting vibration amplitudes analogous to image holography, except that the film emulsion is replaced by a television target.

A method of erasable optical data storage in which information is stored by visible light, then read by illumination with an infrared source that returns trapped electrons to their ground state....

The method by which photographic film is scanned by an electron beam. One technique uses the uniform light of a television screen, focused by a lens onto the processed film, as a means of creating a...