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 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 audio compact disc

: Microscopic depressions called pits and flat areas called lands are pressed into the plastic. : A thin coating of aluminum (or gold)

: A 1.2 mm thick layer of clear polycarbonate plastic . The sensor translates these light changes into electrical

The , officially known as Compact Disc Digital Audio (CD-DA) , is a digital optical disc data storage format. Co-developed by Sony and Philips and commercially introduced in 1982 , it revolutionized the music industry by offering superior sound quality, durability, and portability compared to analog formats like vinyl and cassettes. Technical Design & Functionality

: A film of acrylic lacquer seals the reflective layer to prevent corrosion and physical damage. How It Works