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:
Apr. 21, 1987
Filed:
Mar. 22, 1985
Yoshihiro Tsukamura, Kanagawa, JP;
Toshiro Morimoto, Kanagawa, JP;
Matayasu Kubo, Kanagawa, JP;
Masataka Mukai, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
This invention relates to an optical disk recording and reproducing apparatus for recording a predetermined signal on and/or reproducing the same from a writable disk which is rotated at a constant linear velocity by using a laser from a laser source. In this case, upon reproducing the above-described signal, if a signal recorded on the inner periphery of the disk is accessed, during the period from this addressing up to the time when the linear velocity at the inner periphery of the disk becomes constant, on the basis of a spindle lock signal, the beam power of the laser from the laser source and irradiating the disk is decreased to thereby prevent useless data from being rewritten on the disk.