Patent · US Expired

Optical disk storage which provides pull-in of focus servo and pull-in of tracking servo

US5438557A · kind A · utility

4Cited by
8References
18Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 24, 1994
Grant dateAug 1, 1995
Priority date
Expiry dateMar 24, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/0945
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A miniaturized optical disk apparatus which performs a pull-in of a focus servo and a pull-in of a tracking servo without a position detector for detecting an optical head. If the optical head is located at a non-reflection film area and thus the focus servo cannot be performed, then the optical head is moved and the focus servo is performed again. This process is repeated until the focus servo can be achieved. In addition, if the optical head is located at a non-track area, then the optical disk is moved to a track area and then the tracking servo is performed. This process also repeated until the optical head is located over the track area. The tracking servo can be stably performed since it is performed only when the optical head is located over the track area. The present invention is applicable to the optical disk apparatus which uses a 3.5 in optical disk.

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