Photonics Dictionary: C

The Casimir force is a quantum phenomenon that results in an attractive force between two closely spaced uncharged conductive surfaces. This force arises from the quantum vacuum fluctuations of the...

Description of a particle that cannot be superimposed on its mirror image.

Chirality is a property of certain molecules and objects in which they are non-superimposable on their mirror images. In other words, a chiral object or molecule cannot be exactly superimposed onto...

Chirped mirrors are optical devices designed to manipulate the spectral properties of ultrashort laser pulses. They consist of multiple layers of dielectric coatings deposited on a substrate, where...

A laser whose pulses are expanded, using gratings and optical fibers, before amplification and compressed to increase beam intensity without damage to the optical train.

Chirped pulse amplification (CPA) is a technique used in laser physics to amplify ultrashort laser pulses to high energies without causing damage to the amplifying medium. The method was first...

A rapid change, as opposed to a long-term drift, of the emission wavelength of an optical source. Chirping is most often observed in pulsed operation of a source.

The image of a point source that appears as a circle of finite diameter because of defocusing or the aberrations inherent in an optical system.

Best point of focus for an image in a beam of light at the smallest cross section of the beam.

The optical phenomenon in which right circularly polarized light transmitted by an active medium travels at a different velocity than that of left circularly polarized light.

A type of spectroscopy used extensively in the analysis of biological samples. Because most biologically synthesized molecules, such as proteins, are optically active, circular dichroism spectroscopy...

Circular dichroism (CD) is a spectroscopic technique used to study the structural characteristics of chiral (asymmetric) molecules, particularly biomolecules like proteins, nucleic acids, and certain...

Scanning characterized by the generation of a plane or right circular cone with a vertex angle of about 180° by the direction of maximum radiation.

An optical interference coating, vacuum-deposited on a circular substrate, whose transmission characteristics may be varied by physical rotation.

A light beam whose electric vectors can be broken into two perpendicular elements that have equal amplitudes and that differ in phase by l/4 wavelength.

A passive device, having three or more ports, in which input light from one port is coupled only to the next sequential port in a given direction and is prevented from traveling in any other...

The halo phenomenon of a brightly colored arc having the colors of the rainbow and lying parallel to the horizon.

A television system that does not broadcast television signals but transmits them over a closed circuit.

Electronic circuit capable of distinguishing the pulses emitted by separate counters in a given time phase and determining whether the pulses were emitted by the same particle or correspond to a...

A mirror whose coating serves to reflect visible radiation while transmitting the infrared.

An early graphic scheme of colors in which saturated spectral colors are plotted around the circumference of a circle. Complementary colors face each other across the circle's diameter.

Concave and convex spherical mirrors are types of curved mirrors that have surfaces shaped like segments of spheres. These mirrors are commonly used in optics for various applications, including...

The coupled pairs of electrons that carry supercurrents through the body of a superconductor, relative to a coherent macroscopic wave function with the superconductor.

Fine lines, wires or threads used in the focal plane of many optical instruments to point out and locate particular objects in the field of view. They were formerly made from a single strand of...

A standard lens interface initially made for 16mm movie cameras and now used primarily on closed-circuit television cameras. It is a 1-in.-diameter, 32-thread-per-inch interface with a...

The three lines in the spectrum of cadmium that have the purest radiations and that were first used by Michelson to calculate the standard meter.

A microscope that allows examination of a small crystal and conveniently provides linearly polarized object and reference beams so that, by suitable orientation of an anisotropic crystal, the optical...

The production of visible light by infrared radiation whereby the light is produced by heat and not by any direct change in wavelength; the transformation is indirect.

Name originally given to the sun's infrared radiation by Sir William Herschel in his Philosophical Transactions of 1800.

Calorimetry is a branch of science that involves the measurement of heat flow in physical or chemical processes. It encompasses various techniques and instruments used to quantify heat transfer,...

An electromagnetic device used to separate isotopes of elements based on their respective masses.

Camera Link HS (high speed) is a standard developed for high-speed digital data transmission in machine vision and industrial imaging applications. It is an evolution of the original Camera Link...

A portable instrument that uses a four-sided reflecting prism or set of mirrors to create a duplicate image of an object on a horizontal sheet, on which outlines of the subject may be traced by hand.

The use of the photographic process to produce precision copies of an original image that are many times smaller in size. One of its many applications is in microcircuitry.

A resin obtained from the balsam fir, Abies balsamea, used as a lens cement.

A device that accumulates and stores electrical energy to introduce capacitance into a circuit. Basically, it is composed of two electrical conductors, separated by an insulating medium.

An instrument incorporating an infrared detector assembly, used to analyze carbon dioxide gases and in medical applications to monitor air exchange in the lungs of patients on ventilators or under...

A gas laser in which the energy-state transitions between vibrational and rotational states of CO2 molecules give emission at long IR, about 10 µm, wavelengths. The laser can maintain...

Carbonization is a process in which organic materials are heated in the absence of air, leading to the decomposition of the material and the production of carbon-rich residue. During carbonization,...

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor material. Semiconductors are materials with electrical conductivity between...

An image tube that functions in low-light-level conditions by virtue of its series of stacked sections wherein the output of one section becomes the input for the next.

A heterochromatic photometric process using successive comparison of similar chromaticities and the calculation of relative luminances of unlike chromaticities as the product of ratios of luminances...