8,738 terms
Photonics Dictionary
Search 8,700+ definitions in the Photonics Dictionary—your authoritative source for terms in optics, lasers, imaging, fiber optics, and related technologies.
counting chamberIn microscopy, the chamber that is contained on a microscope slide to hold a certain amount of fluid. It is calibrated accurately to determine the number of cells and other elements while the...
coupled rangefinderA rangefinder on a camera that is integrated with the focusing mechanism so that when an object's range is determined, the camera is automatically in focus.
coupler1. In color development, the chemical that combines with certain by-products of the development procedure to form a dye. 2. Device for distributing optical power among two or more ports. 3. Device...
coupling efficiencyThe fraction of available output from a radiant source that is coupled and transmitted by an optical fiber.
COVcoefficient of variation
covalent crystalA crystal formed by covalent bonds that are generally highly directional by nature. The electric characteristics of these crystals classify them as semiconductors.
covered grooveA technique used in integrated optics where a groove is cut on a substrate surface and covered by a thin film to facilitate the construction of filters, resonators, beamsplitters and grating couplers...
coverslipA coverslip, also known as a cover glass or cover slip, is a thin and flat piece of transparent material typically made of glass or plastic. It is used in microscopy to cover a specimen mounted on a...
cpcandlepower
cPcentipoise
CPCcompound parabolic concentrator
CPDcharge-primed device
CPHcomputer polarization holography
CPIcommon path interferometry
CPMcolliding pulse mode
cpmcycles per minute
CPScathode potential stabilization
cpscycles per second
CPUcentral processing unit
CPVconcentrator photovoltaic
CRcathode ray; command register; control relay; coupling ratio; crystal rectifier
CRADAcooperative research and development agreement
Craik-O'Brien effectObserved when alterations in the luminous sterance at the contour of an object create the illusion of the outer zones appearing darker than the inner regions, despite the consistent luminance of the...
crater lampA glow-discharge tube in which the discharge takes place in the conical or crater-shaped depression at one end of the tube.
Crayford focuserA high-quality focuser that uses rollers rather than gears and offers smooth, precise motion while reducing or eliminating image shift and backlash.
CRDcapacitor resistor diode
CRDFcathode-ray direction finding
creepThe deformation of a material at high levels of stress, often associated with elevated temperatures.
cresyl violetCresyl violet, also known as cresyl violet acetate or cresyl echt violet, is a synthetic organic compound belonging to the class of triarylmethane dyes. It is commonly used in histology and...
CRIcolor rendering index
cribbingThe breaking of the excess glass from the specified shape.
crimp sleeveA crimped metal cylinder that holds the connector to the cable through the cable's strength member.
critical absorption wavelengthThat wavelength at which the absorption of a given element or system begins to demonstrate an inconstant value.
critical angleThe least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense medium, at which the light is...
critical apertureIn an optical system, the aperture size at which the lens gives its best overall performance.
critical flicker frequencyRelative to a light source, the frequency at which the source appears to fluctuate in light intensity half the time and remains constant during the other half.
critical fusion frequencyThe fusion frequency of flicker that is needed just to produce complete fusion and to assure the visual sensation of continuous illumination measured in cycles per second.
critical illuminationIllumination in which the light source is imaged at the object.
critical scatteringIntense scattering in the region of the liquid-gas critical point. At this point the gas will strongly scatter all light to create a vivid opalescent appearance.
CRLAconstrained run length algorithm
CRMcounter-radar missile; counter-radar measures
CROcathode-ray oscilloscope
Crookes radiometer -> radiometerA device used to measure the intensity of radiant energy.
cross dispersionRecombination of only the light that is correctly dispersed by the first stage of a polychromator through its wide intermediate slit (common during Thomson scattering experimentation), which is...
cross roller slideA positioning slide mechanism with two rows of alternately crisscrossed cylindrical rollers.
cross sectionCalculation of the probability of an interaction between two types of particles, such as light absorption, excitation or energy transfers. The probability that one incident particle will interact as...
cross wireFine 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...
cross-correlationA signal-averaging technique that improves signal-to-noise ratio by comparing a sampled signal with a reference signal bearing some known relation to the received signal.
cross-coupling1. A defect inherent in a multiple-axis positioning system whereby an adjustment of one axis causes an undesired change in another; its severity depends upon the degree to which the positioning axes...
cross-linked plasticPlastic in which the polymer chains become irreversibly joined during molding. The cross-linking can be achieved by heating, chemical agents or irradiation.
Photonics Dictionary