Photonics Dictionary

An optical instrument containing a gimballed sighting telescope, used to measure angular relationships in horizontal and vertical planes.

1. In relation to cathode-ray tube displays, errors in the signal's amplitude, phase or both that result in small, rapid aberrations in size or position of the image. 2. Errors of synchronization...

A unit of energy or work in the MKS system of units. One joule is equal to 107 ergs.

A semiconductor device with the property of conducting current more easily in one direction than the other. It has two terminals containing a single crystal of semiconducting material that ranges...

In an interlaced scanning electro-optical system such as television, the system resolution will be less than the number of active scan lines because of the random phase nature of the object being...

An eyepiece consisting of a planoconvex field lens and a cemented doublet as the eye lens.

The SI unit of temperature equal to 1°C. See absolute temperature scale.

The material lost during a laser cutting or machining operation.

A cell filled with a transparent material that, when placed in a strong electrical field, exhibits double refraction. Since the two polarized elements of an incident light beam travel at different...

The Kerr effect, named after the physicist John Kerr who first observed it in 1875, is a nonlinear optical phenomenon where the refractive index of a material changes in response to an applied...

A Kerr soliton refers to a specific type of soliton, a self-reinforcing wave packet, that arises in nonlinear optical systems due to the Kerr effect. The Kerr effect is the phenomenon where the...

A type of geometrical distortion that brings about a trapezoidal display of a nominally rectangular picture. Usually produced when a picture is projected abnormally to the screen.

In the SI system, prefix meaning one thousand, 103.

A unit of frequency that equals 1000 cps. Abbreviated kHz.

A unit of energy or work that is equal to 1000 (103) joules. Abbreviated kJ.

A cathode-ray tube that serves as a picture tube in a television receiver. The signal representing the picture intensity is transmitted to the electron gun grid so that the beam intensity varies with...

An atmospheric nonlinear process unique to CO2 laser wavelengths, whereby CO2 absorbs 10.6-µm radiation and the CO2 molecules in the (100) vibrational state are excited to the (001) level, and...

A thermionic tube that has a velocity-modulated electron stream and that may be used as a microwave amplifier or oscillator.

Westinghouse trade name for an alloy of iron, nickel and cobalt, which has the same thermal expansion as glass and therefore is often used for glass-to-metal or ceramic-to-metal seals.

An arc lamp that has its cavity filled with krypton to produce a light source with unique characteristics.

A lab-on-a-chip (LOC) is a miniaturized device that integrates various laboratory functions and capabilities onto a single, compact chip. Also known as microfluidic devices, lab-on-a-chip systems are...

A term applied to an electric charge image in a camera tube that remains for a period of a few frames after its initial formation.

Flux per unit solid angle leaving a surface in any direction is proportional to the cosine of the angle between that direction and the normal to the surface. A material that obeys Lambert's cosine...

A unit of luminance equal to 1/p candela per square centimeter. (l).

An optical source that has a luminous distribution that is uniform for all directions.

A device designed to concentrate and direct a light source by enclosing the source in it and using a concave reflector to direct the light through its only opening.

A dark band that may appear in the field of crossed Nicol prisms with a powerful source such as the sun because the light is not strictly parallel and is not extinguished immediately.

A broken circle used as the test object in distinguishing visual acuity. The width of the gap in the circle is equal to the breadth of the black line and one-fifth the circle diameter. Also known as...

Edge enhancement technique that accentuates all edge details in an image without discriminating as to spatial orientation.

Lapping and polishing services involve specialized processes used to improve the surface finish and dimensional accuracy of components to meet specific requirements or standards. These services are...

Laser ablation is a process that involves the removal or erosion of material from a target surface using laser energy. This technique is widely used in various scientific, industrial, and medical...

An experimental research technique by which absorbed or unabsorbed radiation is analyzed in order to characterize and determine material properties, concentration as well as behavior under the...

Laser active elements typically refers to the substances or materials within a laser system that play a critical role in the amplification of light through the process of stimulated emission. These...

The process by which laser emission is used in measuring fluid velocity and, more specifically, the detection of air and wind velocity.The laser technique measures the amount of frequency shift...

Laser annealing is a process that involves using a laser beam to heat and modify the microstructure of a material, typically a thin film or surface layer, with the objective of improving its...

A laser cavity, also known as an optical cavity or resonator, is a fundamental component of a laser system. It is a confined region or space where light undergoes multiple reflections, leading to the...

A device used for measuring the height of clouds from a position on the ground. Measurement technique uses a vertically directed beam stably positioned such that scattered radiation may be detected...

A moving group of fluid-suspended biological species directed through separate channels by which the population is isolated. The isolated or purified group is observed by applying a laser detection...

A scanning laser radar system applied to transmission and concentration analysis in three dimensions of clouds as well as aerosols and other particles within atmospheric systems.

Laser cooling is a technique used to reduce the temperature of a material or a collection of atoms or molecules by using laser light. It is based on the principle of selective absorption and emission...

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of lasers. The primary function of the laser crystal is to amplify light by...

A natural or mechanical system adversely affected by the influence of laser radiation. During laser damage the common effect of the radiation on the surface of interest is heat accumulation due to...

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing damage. It is a critical parameter in laser applications and is...

A laser device used to establish a location or target usually for detection by an impact source e.g. missiles and guided munitions. Laser designation sources utilize a system configuration which is...