Photonics Dictionary

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.

In the tolerancing of optical elements, the displacement of the optical axis from the mechanical axis.

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.

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...

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...

The finishing of the edge of an optical element by grinding.

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

A unit of energy equal to the amount of energy absorbed by one molecule of material undergoing a photochemical reaction, as determined by the Stark-Einstein law.

A change in the refractive index of an optical fiber caused by variation in the length of the fiber core in response to mechanical stress.

The organic inclusion in quartz crystal that forms delicate films and microspheres and that shows a maximum absorption at 450 nm.

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

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.

An electro-optic deflector is a device that can change the direction of light beams using an electric field. It operates based on the electro-optic effect, which involves the modulation of the...

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...

1. The branch of physics that deals with the use of electrical energy to create or manipulate light waves, generally by changing the refractive index of a light-propagating material; 2....

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 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 deposition of a metallic coating, usually nickel, on a component by chemical means rather than by electroplating; the component is immersed in a solution containing a reducing agent.

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...

The distribution of electromagnetic fields in a given area. The units are volts per meter, watts per meter squared and joules per meter cubed.

The total range of wavelengths, extending from the shortest to the longest wavelength or conversely, that can be generated physically. This range of electromagnetic wavelengths extends practically...

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...

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...

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...

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.

1. A device generally used in a cathode-ray or camera tube to emit a stream of electrons moving at uniform velocity in a straight line. It consists of an emitting cathode and an anode, with an...

An electron-beam lithography (EBL) system is a sophisticated nanofabrication tool used in the semiconductor industry and research laboratories to pattern extremely fine features with sub-micrometer...

An electron-gun system is an assembly used to generate and control a focused beam of electrons. Electron guns find applications in various fields, including cathode ray tubes (CRTs), electron...

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

A nonmagnetic instrument utilizing an electrofocus and deflection tube with a photocathode for imaging purposes. The optical image is converted into a photoelectric output at the photocathode and is...

An image intensifier that uses electrostatics to amplify and focus the electronic image.

An electrowetting display (EWD) is a type of electronic display technology that utilizes the principles of electrowetting to control the behavior of colored oil droplets on a hydrophobic surface....

Ellipsometry is an optical technique used to characterize the properties of thin films and surfaces. It is based on the measurement of changes in the polarization state of light reflected or...

The term "embedded laser" typically refers to a laser device that is integrated or embedded into a larger system or structure. In this context, "embedded" implies that the laser is an integral part...