The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 1992
Filed:
Aug. 29, 1990
Applicant:
Inventors:
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ; G11B / ;
U.S. Cl.
CPC ...
369 13 ; 360 59 ; 360114 ; 365122 ;
Abstract
A high density magnetooptical recording and playback method is disclosed. The magnetooptical recording medium comprises a recording hold magnetic layer and a playback magnetic layer magnetically coupled with each other. Prior to the playback operation, the playback magnetic layer is initialized by an external magnetic field. A laser light is irradiated to locally heat the medium and cause transfer of magnetization in the recording hold magnetic layer to the playback magnetic layer. The signal is read out by the interaction of the laser light and the transferred magnetization.