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:
Jan. 07, 2003
Filed:
Jul. 07, 1999
Wataru Tsukahara, Kawasaki, JP;
Shigenori Yanagi, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A tracking control method carries out a tracking control based on a tracking error signal which indicates an error of a beam spot formed on a recording medium by a light beam from a light source with respect to a track. The tracking control method includes detecting a change in a light emission power of the light source, calculating a correction quantity which is used to correct a shift and/or fluctuation of the tracking error signal generated due to the change in the light emission power, and carrying out a correction by adding the correction quantity to the tracking error signal when the change in the light emission power is detected.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile