Patent · US Expired

Magneto-optic recording and reproducing apparatus including a multiple layer recording medium having a premagnetized bias layer replacing an external bias magnetic

US5025430A · kind A · utility

13Cited by
8References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 1988
Grant dateJun 18, 1991
Priority date
Expiry dateMar 31, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B11/10536
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magneto-optic recording a reproducing apparatus including a magneto-optic information-carrying medium having three magnetic layers. A magnetic bias field is generatedd by a third layer which is premagnetized in the direction parallel to the thickness thereof. A second layer is magnetized by a magnetizing unit. The laser beam incident on the layers is controlled to three intensities for writing and reading information.

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