Photonics Dictionary: E

In image processing, the location of edges by employing templates that respond to the first or second derivative of gray-scale intensity in the neighborhood of each pixel.

1. That portion of the aperture that functions to collect energy and deliver it to the final system detector. 2. For an obscured or noncircular aperture, the equivalent nonobscured, circular aperture.

A device that detects radiation by utilizing the influence of light in forming an electrical signal. It may be a phototube; a photoconductive, photovoltaic or photojunction cell; a phototransistor;...

An EMCCD (electron-multiplying charge-coupled device) camera is a type of scientific camera specifically designed for low-light imaging applications that require high sensitivity and fast readout...

A method for detecting vibration amplitudes analogous to image holography, except that the film emulsion is replaced by a television target.

An enzyme-linked immunosorbent assay (ELISA) is a laboratory technique used to detect and measure the presence of specific substances, such as antibodies, antigens, proteins, hormones, or other...

The addition to the information signal in communications of redundant bits that enable the originally encoded message to be decoded without degradation of the data. In compact disc technology, the...

A factor, F, indicating the increase in shot noise in an avalanche photodiode as compared with the ideal multiplier, which is noiseless. The noise, which results from variations in avalanche gains,...

A small incandescent lamp whose intense beam is focused on the optical soundtrack of a motion picture film. The soundtrack modulates the beam, which in turn is detected by a photocell that produces...

A photodetector composed of a semiconductor material whose responsive properties can be altered by the addition of impurities to the basic material. Copper- and mercury-doped germanium are both...