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:
Dec. 21, 2004
Filed:
Jan. 02, 2002
Minoru Hirashima, Osaka, JP;
Funai Electric Co., Ltd., Osaka, JP;
Abstract
In a focusing servo apparatus for an optical pickup, an S-shaped wave of a focus error signal is measured at a point of time T to thereby calculate the time &Dgr;t required for shifting the position on the S-shaped wave from a local maximum value to a local minimum value. The speed of a lens relative to an optical disk is measured on the basis of the time &agr;t . When the relative speed of the lens is higher than the speed allowed to lead the focus in, the motion of the lens is braked just before (a point of time T ) the optical disk makes one rotation to thereby reduce the relative speed of the lens to make it possible to lead the focus in the optical disk steadily.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile