Photonics Dictionary: C

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...

SI unit of luminous intensity. It is defined as one sixtieth the normal intensity of one square centimeter of a blackbody at the solidification temperature of platinum. A point source of one candela...

The luminous intensity of a source of light expressed in candelas.

The luminescence of an incandescent material.

An oil immersion condenser used to permit only light that has been diffracted or dispersed by a microscope specimen to enter the microscope. It is used in dark-field microscopy.

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....

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...

An optical instrument used to determine the distance to a target being viewed. Two similar optical systems view the target via 45° mirrors at the ends of a fixed baseline. One system creates the...

A CIE index describing the changes in color of standard test objects when the illumination is changed from a standard to a test illuminant.

The maximum rate at which temporally disjunct optical signals can be produced or detected.

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

Complementary metal-oxide-semiconductor (CMOS) refers to a technology used in the fabrication of integrated circuits, particularly semiconductor devices like microprocessors, memory chips, and image...

A device for obtaining very low crosstalk in a crosspoint by arranging two simple switches along different arms of a passive crossover and connecting the switches with a curved connecting guide to...

A lens composed of two or more separate elements of optical glass that may or may not be cemented together. The surfaces of the elements are shaped to reduce or eliminate the aberrations inherent in...

A semiconductor made up of two or more elements, in contrast to those composed of a single element such as germanium or silicon. In a III-V semiconductor, for example, one or more elements having...

A center-opening shutter made up of several identical leaves that are mounted symmetrically around the optical axis of the lens.

Computer numerically controlled (CNC) grinding is a manufacturing process that utilizes computerized controls and precision machining tools to remove material from a workpiece. In CNC grinding, a...

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...

A single positive lens or group of lenses used in a projection system to collect light from a source and cause it to illuminate evenly the object to be projected.

A material property that is the inverse of its resistance to the flow of electricity.

A partially filled or empty energy band through which electrons can move easily. The material can therefore carry an electric current. The term is usually applied to semiconductors.

A type of laser welding of thin materials using a defocused or low-power carbon dioxide laser beam. The energy is absorbed by the material through conduction and melts the material to produce an edge...

An optical wedge of very small angles that admits light while sealing out moisture and dirt and that may be rotated to compensate for the errors in the entire system. Correction windows are sometimes...

Bohr's formulation that every new theoretical principle must correspond to the salient classical predecessor. The principle imposes mathematical limits on theoretical discovery and implies, for...

A 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.

Custom 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...

In a cylindrical lens, the meridian parallel to the generating lines of the cylindrical surface. In a toric lens, the cylinder axis is the axis of the equivalent cylindrical surface that has been...

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape resembling a cylinder. Unlike spherical lenses, which have the same...

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 CMOS image sensor, short for complementary metal-oxide-semiconductor image sensor, is a type of semiconductor device used to capture visual information and convert it into electrical signals for...

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...

A mercury vapor discharge lamp that has cadmium added to emit radiation in the red region as a complement to the mercury vapor's blue and green radiation.

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.

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 photoconductive cell having cadmium sulfide as its photoconducting material for the production of a very high dark-light resistance ratio.

A doubly refracting mineral used to produce polarizing prisms. It is uniaxial negative and in the trigonal division of the hexagonal system of crystals. Its indices are e = 1.486, w = 1.658; its...

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...

An optical material used in place of crown glass to produce lenses with extraordinary correction of chromatic aberrations. Its high coefficient of thermal expansion and its tendency to absorb...