Audio Compact Disc Link

CD players use a to scan the disc from the center outward along a spiral track. When the laser hits a pit , it scatters the light; when it hits a land , the light is reflected back to a sensor. The sensor translates these light changes into electrical signals (zeros and ones), which are then converted back into high-fidelity audio. The Compact Disc: An Introduction

A standard audio CD is a 120 mm (4.7 in) circular disc composed of several layers: audio compact disc

: A thin coating of aluminum (or gold) reflects the laser beam used for reading. CD players use a to scan the disc

: Microscopic depressions called pits and flat areas called lands are pressed into the plastic. it scatters the light