Referring to the diagram, a compact disk player reads information from a compact disk (1) using a focused laser (2). Music or other information is written on the underside of the disk in a spiral track of pits (3), representing a digital code of zeros and ones. The disk spins and the laser, mounted on a swing arm (4), moves as the disk plays. The laser passes through a semi-silvered mirror (5) and is focused on the disk (6). When the laser hits a flat area it is reflected back via the mirror to a sensor (7) and the information sent to a chip. When the laser hits a pit, it is scattered.
Related category TECHNOLOGY
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