Patent · US Expired

Magneto-optic recording/reproduction apparatus for minimizing variation in focusing error signals caused by variation in optical source wavelength

US5297114A · kind A · utility

27Cited by
7References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 29, 1991
Grant dateMar 22, 1994
Priority date
Expiry dateNov 29, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/094
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In the magneto-optic recording/reproduction apparatus, a light beam from a semiconductor laser that can be used with two wavelengths, for recording and reproduction is converged by an objective lens on a magneto-optic disk, a predetermined offset is added to this focusing error signal by an offset adjusting circuit, and the objective lens is driven in the direction of the optical axis based on the focusing error signal to which an offset was added.

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