Patent · US Expired

Optical disk device with optical path length changing member

US5986982A · kind A · utility

0Cited by
2References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 7, 1997
Grant dateNov 16, 1999
Priority date
Expiry dateNov 7, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0006
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical disk device for projecting laser light emitted from a laser light source on an optical disk to reproduce information has a support shaft which is disposed nearly parallel with an optical axis of the laser light. The support shaft is fixed on a mount. A lens holder is rotatably disposed around the support shaft and reciprocally movable along the support shaft as well as holding an objective lens for converging the laser light upon a recording plane of the optical disk. The device also includes a tracking drive for energizing the rotation movement of the lens holder, and a focusing drive for energizing the reciprocative movement along the support shaft of the lens holder. An optical path length changing member is provided which has a change region where an optical path length is changed when the laser light is transmitted therethrough and an unchanged region where an optical path length is not changed when the laser light is transmitted therethrough is located closer to the optical disk than the lens holder and rotatably disposed around the support shaft and reciprocally movable along the support shaft. Completing the device is a linking mechanism for variably effecting th…

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