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:
Oct. 21, 2008
Filed:
Mar. 26, 2004
Kenichi Furukawa, Kanagawa, JP;
Yuichi Maekawa, Kanagawa, JP;
Kenichi Furukawa, Kanagawa, JP;
Yuichi Maekawa, Kanagawa, JP;
Mitsumi Electric Co., Ltd., , JP;
Abstract
A method for adjusting a focus bias in an optical disc drive comprises the steps of: rotationally driving an optical disc in a state that only focus servo is engaged without engaging tracking servo; driving an actuator of an optical pick-up so that a laser beam projected from the optical pick-up is moved in a tracking direction to obtain an HF signal; and determining a focus bias by which a proper focusing point can be obtained based on the HF signal. The driving of the actuator is carried out by supplying an actuator drive control signal to a tracking actuator of the optical pick-up in a state that tracking servo is not engaged.