Photonics Dictionary: C

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 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.

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

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...

A two-mirror lens design used in astronomical telescopes, the primary being a parabola, the secondary a smaller hyperbola. The image formed is free of spherical aberration and color and is located...

A system that uses both reflection and refraction to achieve its focal power. While the relative powers of the lenses and mirrors vary from system to system, the use of the reflective surfaces to...

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the form of light, into an electrical signal. Photocathodes are components used in...

An optical system in which the only image-forming elements are curved-surface mirrors; e.g., a Cassegrain lens system.

A CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and record images. CCD cameras are widely used in various applications,...

A CCD image sensor, or charge-coupled device image sensor, is a type of electronic device used to convert optical images into electronic signals. It is a key component in digital cameras, camcorders,...

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....

The center of the sphere of which the surface of a lens or mirror forms a portion. Each curved surface of a lens has a center of curvature; the surfaces may be convex or concave.

1. Mounting a lens or mirror so that its optical axis is coincident with the optical or mechanical axes of other portions of the system. 2. The machining (edging) of the outside diameter of a lens...

Chalcogenide refers to a class of compounds containing elements from group 16 of the periodic table, which includes sulfur (S), selenium (Se), and tellurium (Te). These elements are known as...

A charge-coupled device (CCD) is a type of electronic image sensor used in various imaging devices, including digital cameras, camcorders, and scientific instruments. It consists of an integrated...

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 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.

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 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 mode that is confined by virtue of a lower-index medium surrounding the cladding. Cladding modes, in the terminology of mode descriptors, are equivalent to cladding rays in the terminology of...

Denoting a finished circular edge. A decentered lens is adjusted on a centering chuck so that its image runs true, and the lens is then edged. A circular edge is one that has been cleared out....

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...

Cold atoms refer to atoms that have been cooled to extremely low temperatures, typically in the microkelvin (µK) to nanokelvin (nK) range, close to absolute zero (0 Kelvin or -273.15°C). At...

A convex or positive lens that serves to collect energy and direct it into subsequent system optics.

A positive lens located at or close to an intermediate image plane. The collector refracts off-axis light bundles, directing them into the apertures of subsequent optics.

An optical instrument consisting of a well- corrected objective lens or mirror with a light source and or object/image (i.e. illuminated slit or retical) at its focal plane. Collimators are used to...

A color center, in the context of materials science and condensed matter physics, refers to a specific type of crystallographic defect in a crystalline structure that introduces color to the...

A laser warning and countermeasure system containing a sensor that indicates the direction of a laser beam, and analytical instruments to determine pulse code, repetition frequency and wavelength.

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...

1. A constituent part. It may consist of two or more parts cemented together, or with near and approximately matching surfaces. 2. The projection of a vector on a certain coordinate axis or along a...

Concave is an adjective used to describe a surface or shape that curves inward or has a hollow or recessed appearance. In the context of geometry or optics, a concave shape is one that curves or...

The two points on the principal axis of a mirror or lens so positioned that light emitted from either point will be focused at the other, i.e., object and image points.

The ratio between the object distance and the image distance measured along the principal axis of a lens or mirror. An object at the focal point of a lens has an infinite conjugate ratio; an object...

Convex is an adjective used to describe a surface or shape that curves outward, bulges, or has a rounded and outwardly extending appearance. In the context of geometry or optics, a convex shape is...

A semispherical or conical lens created directly on the core of an optical fiber to focus light from a laser into the fiber core.

A corner cube, also known as a corner reflector or retroreflector prism, is a type of optical device used to reflect light or electromagnetic waves back towards their source with minimal deviation in...

Relative to the Cotton-Mouton effect, the magnetic birefringence constant that, when multiplied by pathlength and the square of the magnetic field strength, yields the phase difference between the...