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:
Nov. 22, 1994
Filed:
Apr. 26, 1994
Sony Corporation, Tokyo, JP;
Abstract
This invention is directed to an improvement in a novel magneto-optical disc reproducing method of the record information erasing type or the record information raised or transfer type wherein a technique is employed to prevent the dimension of an actual reproduction region from varying by a change of temperature or linear velocity of a magneto-optical disc. To realize this, reference information is recorded on a magneto-optical disc to reproduce this reference information prior to actual data reproduction to detect the regenerative RF signal level to control a laser power or an external magnetic field so that the regenerative RF signal level becomes equal to a level optimum for reproduction, thus allowing the dimension of an actual reproduction region to be an optimum fixed dimension at all times. At the time of actual reproduction, control is made so that the controlled laser power or external magnetic field is maintained.