optical disc

computer technology

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Last updated

July 1, 2026

Quick Summary

Optical discs are a computer storage medium that uses lasers to read and write digital data. A laser beam encodes data onto the disc's surface as tiny pits. A scanner reads these pits, converting reflected light variations into electrical signals.12

This technology offers higher storage capacity than magnetic storage because lasers can focus more precisely, allowing data to be condensed into a smaller space. Optical discs are also inexpensive to produce and are not susceptible to power outages or magnetic interference.1

Common examples include the compact disc (CD) for audio, CD-ROM for computer data, and WORM (write-once read-many) discs. Newer rewritable versions also exist. While optical discs provide excellent storage, their information retrieval rate is slower than magnetic media.13

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information processing
Recording media
…recording and storage medium, the optical disc, became available during the early 1980s. The optical disc makes use of laser technology: digital data are recorded by burning a series of microscopic holes, or pits, with a laser beam into thin metallic film on the surface of a 43/4-inch (12-centimetre) plastic…
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…recording and storage medium, the optical disc, became available during the early 1980s. The optical disc makes use of laser technology: digital data are recorded by burning a series of microscopic holes, or pits, with a laser beam into thin metallic film on the surface of a 43/4-inch (12-centimetre) plastic…
Read More

laser
Optical discs
Tiny, inexpensive semiconductor lasers read data from a growing variety of optical compact disc formats to play music, display video recordings, and read computer software. Audio compact discs, using infrared lasers, were introduced around 1980; CD-ROMs (compact disc read-only memory) for computer data…
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Tiny, inexpensive semiconductor lasers read data from a growing variety of optical compact disc formats to play music, display video recordings, and read computer software. Audio compact discs, using infrared lasers, were introduced around 1980; CD-ROMs (compact disc read-only memory) for computer data…
Read More