Laserdisc

Description

An early videodisc that used reflected laser beam to playback audio and video signals to a television. Optical disk technology was patented in 1961 but Laserdiscs did not reach the market until 1978. They were made from thin circular plates of Metal, Glass, or Polycarbonate with a reflective metallic surface. They varied in size form 4.7 to 11.8 inches in diameter. The signal was recorded as a sequence of holes. The laserdisc reader used a Laser to scan the patterns then translated the variations in light intensity into video and audio signals. Laserdiscs were superseded in 1995 by the introduction of digital videodiscs (DVD).

Synonyms and Related Terms

laser disc; laser disk; optical disc; Reflective Optical Videodisc System (initial name); Disco-Vision (2nd name; 1969); DiscoVision (3rd name, 1978, first product marketed); LaserDisc (4th name, 1981); Laserdisc (revised produce name and later common name)

Sources Checked for Data in Record

• Encyclopedia Britannica, http://www.britannica.com Comment: "laserdisc" Encyclopædia Britannica Premium Service. [Accessed 25 Jan. 2006].

• Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Laserdisc (Accessed Feb. 2, 2006)

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998