Photonics Dictionary: C

A technique whereby two laser beams, one at an excitation wavelength and the second at a wavelength that produces Stokes Raman scattering, interact coherently in a sample, producing a strong...

A fiber optic communications system that works on the principles of homodyning or heterodyning. The transmitting laser produces an optical wave that is modulated in amplitude, phase or frequency by...

A coherent fiber bundle (CFB), also known as a coherent fiber optic bundle, is an assembly of multiple optical fibers arranged in a specific geometric pattern to maintain the spatial coherence of...

A light source that is capable of producing radiation with waves vibrating in phase. The laser is an example of a coherent light source.

The manifestation of light from scatterers outside the plane of the object in coherent light systems. The output of these systems is often marred by this noise.

The use of phase conjugation or other methods to increase the power density of a laser beam under adverse atmospheric conditions.

Radiation in which the phase relationship between any two points in the radiation field has a constant difference, or is exactly the same in either the spatial or the temporal mode throughout the...

A condition during laser operation when laser output can no longer be increased by additional electric current.

A sudden, brief increase in current or voltage in a circuit that can damage sensitive components and instruments. Preventive measures include slow-starter circuits, filtering and static control.

An inorganic compound, yellow to orange in color, that fluoresces strongly enough when bombarded by a high-current-density electron beam to be used as a high-intensity light source.

A calcium indicator is a molecule that is sensitive to changes in calcium ion (Ca2+) concentrations in biological systems. These indicators are commonly used in various fields, including cell...

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,...

The storage surface of an electron beam tube that is scanned by an electron beam to generate an output-signal current corresponding to the charge-density pattern stored.

A light-tight box that receives light from an object or scene and focuses it to form an image on a light-sensitive material or a detector. The camera generally contains a lens of variable aperture...

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...

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...

The apparent luminosity or glow that immediately envelops the cathode in a gas-discharge tube operating at low pressures. The glow increases as the pressure decreases.

An adaptation by Philips and Sony of their audio compact disc technology for optical disc data storage and retrieval. Current capacity of a disc is 0.5 to 0.6 gigabytes of information.

1. A single unit in a device for changing radiant energy to electrical energy or for controlling current flow in a circuit. 2. A single unit in a device whose resistance varies with radiant energy....

A rotating chamber that can be spun at different speeds to generate great radial forces used to simulate different gravity loads.

A lamp that emits light as the result of the passage of an electrical current through ionized cesium vapor.

Chip-on-board (COB) lights refer to a type of LED lighting technology where multiple LED chips are directly mounted onto a substrate, typically a printed circuit board (PCB), without the need for...

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...

A transparent powdered solid immersed in a liquid or plastic of similar refractive index but widely different dispersion; used to isolate narrow spectral regions.

Chromatic aberration is an optical phenomenon that occurs when different wavelengths (colors) of light are refracted by a lens or optical system, leading to a failure to focus all colors to the same...

A technique of using dyes during endoscopy to improve tissue differentiation. Dyes such as methylene blue, Toluidine blue and Lugol's solution all have the ability to stain particular types of cells....

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.

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.

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...

A CMOS camera refers to an imaging device that employs a complementary metal-oxide-semiconductor (CMOS) image sensor to capture digital images. CMOS cameras have become ubiquitous due to their low...

A ring dye laser that uses prisms and a saturable absorber within the laser cavity to shape and shorten the pulses generated. Counterpropagating modes oscillating simultaneously in the ring...

A method of lasing in which free electrons in a laser-produced plasma collide with neonlike ions to excite electrons to states that decay at different speeds, producing a population inversion.

A polariscope used to demonstrate strain inherent in a piece of glass.

A test used to measure the degree of fading of different colored materials, especially those involving organic dyes, which tend to fade when exposed to bright sunlight, to a damp atmosphere or to...

The recording of three or more separate holograms having a different color on a medium, so that illumination with a tricolor beam yields three separate wavefronts, each representing one of the...