optical disc

high-capacity storage medium for storing computer data which is read and written by lasers

In computing, sound reproduction, and  video, an optical disc is a flat, circular, usually polycarbonate disc where data is stored in the form of pits (or bumps) within a flat surface, usually along a single spiral groove that covers the entire recorded surface of the disc. This data is generally accessed when a special material on the disc (often aluminium) is illuminated with a laser diode. The pits distort the reflected laser light. Most optical discs, with the exception of a few such as black CD-ROMs designed for the original Sony PlayStation, have a characteristic prismatic or iridescent appearance created by the grooves in the reflective layer.
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Noun
1. a disk coated with plastic that can store digital data astiny pits etched in the surface; is read with a laser that scans the surface
(synonym) optical disk
(hypernym) memory device, storage device
(hyponym) compact disk, compact disc, CD

adj. แผ่นเก็บข้อมูล (syn. optical disk)