optical disk

optical disk or optical disc

n.

A plastic-coated disk that stores digital data, such as music or text, as tiny pits etched into the surface and is read with a laser scanning the surface. Also called laser disk. See Usage Note at compact disk.

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optical disk or optical disc

A plastic-coated disk that stores digital data, such as music or text, as tiny pits on its surface. The disc is rotated rapidly, and a laser is reflected off the disc to an optical sensor, which is sampled periodically. If the laser strikes the flat area between pits, the sensor picks up the reflection and registers the digital value 1. If the laser strikes one of the pits, it is deflected from the sensor, and the sample value is a digital 0.

Thesaurus

Noun

1.

optical disk - a disk coated with plastic that can store digital data as tiny pits etched in the surface; is read with a laser that scans the surface optical disc compact disc, compact disk, CD - a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser memory device, storage device - a device that preserves information for retrieval DVD, videodisc, videodisk - a digital recording (as of a movie) on an optical disk that can be played on a computer or a television set