Patent · US Expired

Optical reading or writing apparatus

US4881204A · kind A · utility

4Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 22, 1988
Grant dateNov 14, 1989
Priority date
Expiry dateApr 22, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B17/34
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An information-carrying medium having the form of a disc is rotated around a central axis. The temperature of the disc is controlled by a temperature-adjusting element facing the surface of the disc.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.