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. 19, 1994
Filed:
Jul. 02, 1992
Applicant:
Inventor:
Tsuneshi Yokota, Kawasaki, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
369116 ; 369122 ; 369100 ; 369 4433 ; 369 54 ;
Abstract
In an apparatus for optically recording data on and reproducing it from an optical disk, the level of a laser beam in reproducing mode is subjected to feedback control and the level of a laser beam in recording mode is controlled in accordance with the output of a capacitor which stores the level of the laser beam in reproducing mode. This apparatus monitors the output of a photodetector in a feedback circuit, which receives reflection light from the optical disk, and disables emission of a laser beam when a predetermined amount of light is not detected in recording or reproducing mode.