Photonics Dictionary

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....

Cell adhesion refers to the process by which cells interact and attach to neighboring cells or to the extracellular matrix (ECM), a network of proteins and other molecules surrounding cells. This...

Cell migration refers to the process by which cells move from one location to another within tissues or across biological barriers. This fundamental biological process is essential during various...

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...

In a reflecting telescope, the obstruction of the primary mirror by a secondary mirror which blocks a small amount of the light reflected by the primary mirror and introduces additional diffraction.

The computer module whose circuitry interprets instructions and guides the actions of the peripherals. Also known as the mainframe.

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...

Computer hardware or firmware that accesses character patterns stored in read-only memory and displays them at specific coordinates on a screen.

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...

Chemical vapor deposition (CVD) equipment refers to a class of specialized apparatus used in the process of chemical vapor deposition, a technique for depositing thin films of various materials onto...

1. A localized fracture at the end of a cleaved optical fiber or on a glass surface. 2. An integrated circuit.

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...

The state of a liquid crystal in which the molecules are arranged in layers with their long axes in the plane of each layer. The alignment in each layer is parallel and the alignment in adjacent...

Proportions of standard primaries (tristimulus values) required for a color match; ratios of each tristimulus value of a color to their sum. In the CIE colorimetric system, designated X, Y and Z.

CID, or charge injection device, camera refers to a type of imaging device that utilizes a specific kind of solid-state image sensor technology. CID cameras are capable of capturing images in a...

Commission Internationale de l'Eclairage, the international commission on illumination.

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...

The desensitization of the first photographic exposure after it has been subjected to high-intensity radiation.

An area in which airborne particulates can be monitored and controlled so that given size particles do not exceed a specified concentration, thereby eliminating potential dysfunctions in gyroscopes,...

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 defect in an optical system that prevents rays from reaching their intended destination; it can be caused by an undersized aperture, a baffle out of position, etc. In imaging applications, removing...

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...

Coagulation refers to the process of transforming a liquid, particularly blood or a solution containing dispersed particles, into a solid or semi-solid state. This term is most commonly associated...

CoaXPress (CoaXPress or CXP) is a standardized digital interface and communication protocol used primarily in machine vision and industrial imaging applications. It enables high-speed data...

An imaging process in which the single opening of a simple pinhole camera is replaced with many openings called, collectively, the aperture. The recorded picture, which consists of many overlapping...

A reticle carrying patterns of various forms that can be rotated in an optical beam to cause variations in the intensity of the beam. It also is used in infrared detectors to scan the object field...

A numerical representation of the rate at which a material will exhibit dimensional changes as a direct result of changes in temperature.

A plane mirror mounted on a polar axis that lies parallel to the plane of the mirror. When the mirror is rotated once in 48 hours, celestial objects can be made to appear stationary and are...

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...

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...

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 method of applying antireflection coatings to optics that avoids the elevated temperatures normally used. A cold coating will not be as durable as a normal coating.

Collaborative Robot (Cobot): Unlike traditional autonomous robots, which usually work by themselves, a collaborative robot is programmed to work with humans, such as a guide or an assistant. They can...

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.