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:
Jul. 28, 1992
Filed:
Jul. 09, 1990
Toru Sekiguchi, Tokyo, JP;
Yoshihiro Sasaki, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An apparatus and method for recording and reproducing information onto or from a rotating magnetooptic disc such that optimal laser power is maintained throughout the recording process. A test recording laser beam undergoes stepwise power changes as the recording position along a track of the disc changes. The recording signal is read out by a reproducing mechanism corresponding to the stepwise power change. A correcting mechanism utilizes the read-out signal to obtain the optimal power of the recording laser beam. Then, routine recording is carried out utilizing the optimal laser power. As routine recording is carried out, the optimal laser power is corrected depending upon the radial distance of the track being recorded from the center of the disc. As a result, optimal laser power is maintained regardless of the track position on the magnetooptic disc.