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 surface of an element of a compound lens that will produce the cemented interface. The curves of this interface are called inside curves. To facilitate cementing, the two inside curves should...

In the SI system, prefix meaning one hundredth, 10-2.

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.

Centration is the precise alignment of the optical center of a lens or optical element with its mechanical center or the axis of the mounting assembly. It is crucial for ensuring that the optical...

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

A microscope that can be used to observe and magnify microscope specimens while they are being centrifuged. The objective rotates near the periphery of the centrifuge head, and the ocular is...

The radiation produced when a charged particle traverses a medium that has a refractive index considerably greater than unity. The moving particle has a velocity that exceeds the velocity of light in...

A polishing material that has a quicker polishing action than rouge (ferric oxide) and that is cleaner to handle.

An isotope of cesium that emits negative beta particles and has a half-life of 2.19 years; its applications include photoelectric cells and developmental ion propulsion systems.

Colorless crystals used in photoelectric cells and for photosensitive material in cathodes.

A photoemissive detector sensitive to wavelengths up to 1 µm. It has one sharp maximum of sensitivity at 350 nm and a broad maximum at 800 nm.

A phototube having a cesium-coated cathode that has its greatest sensitivity in the infrared region.

A photocathode that exhibits maximum sensitivity in the blue and ultraviolet regions of the spectrum. The sensitivity is obtained by the exposure of a thin layer of antimony to cesium vapor at an...

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 photoelectric detector consisting of a glass tube internally coated with a low conductance material. Voltage applied along the tube causes photoemission from the photocathode at the end of the tube...

In a charge-coupled device, the disappearance of some of the accumulated charge into the silicon during readout.

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...

A charge-injection device (CID) refers to a class of devices that manipulate and detect electrical charge within a semiconductor material. Charge-coupled devices are a specific implementation of this...

In a charge-coupled device, the percentage of each charge packet that is carried over to the next stage of the transport shift register.