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. 19, 1999
Filed:
Apr. 01, 1996
Applicant:
Inventors:
Toru Ikeda, Kawasaki, JP;
Akira Minami, Kawasaki, JP;
Assignee:
Fujitsu Limited, Kawasaki, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4429 ; 369 54 ;
Abstract
A focus control method controls a focus servo system which controls a focus of a light irradiated on an optical disk in an optical disk unit which has a plurality of operation modes. The focus control method includes the steps of (a) reading focus offset information from a memory which prestores focus offset information depending on the operation modes of the optical disk unit, and (b) controlling the focus with respect to the optical disk by supplying the focus offset information read in the step (a) to the focus servo system when the operation mode of the optical disk unit is switched from one mode to another.