Patent · US Expired

High density optical disc and optical disc player

US5838657A · kind A · utility

6Cited by
7References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 8, 1996
Grant dateNov 17, 1998
Priority date
Expiry dateFeb 8, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/13727
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical disc having a track pitch of 0.85 .mu.m, a shortest pit length of 0.49 .mu.m, a pit depth of 100 nm, and a pit width of 0.35 .mu.m is rotate at a linear velocity of 2.4-2.8 m/s such that the same is optically reproduced by a laser beam having a wavelength of 635 nm which is converged to a spot size of 0.9 .mu.m by an objective lens having a numerical aperture of 0.6. Accordingly, data is read from the optical disc at a transfer rate of 5.6 Mbps.

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