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:
Sep. 18, 1984
Filed:
Dec. 31, 1981
Applicant:
Inventors:
Kiichi Kato, Hachioji, JP;
Tsuneo Yanagida, Hino, JP;
Assignee:
Olympus Optical Co. Ltd., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
360 59 ; 360114 ;
Abstract
In a method of recording an information signal in an opto-magnetic record disc which has an easily magnetizable axis perpendicular to its surface, a constant erasing light beam and a modulated recording light beam are focussed by a single objective lens on adjacent tracks and an external magnetic field is applied to the record medium. The erasing and recording operations can be carried out at the same time by inverting the polarity of the external magnetic field track by track.