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:
Sep. 12, 1997
Junichi Nakano, Hino, JP;
Takeru Hokkezu, Hachioji, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A tracking control unit for an optical disk drive comprises a TES detection circuit for detecting a tracking error signal (TES) in an output of a photodetector included in a stationary optical system, a frictional state prediction circuit for predicting a frictional state between guide shafts and a carriage on the basis of the TES detected by the TES detection circuit, a phase compensation filter for compensating for a phase difference of the TES detected by the TES detection circuit so as to stabilize a tracking control system on the basis of the result of the prediction performed by the frictional state prediction circuit, and a driver for moving the carriage in a direction in which a tracking error can be corrected for according to an output of the phase compensation filter and for thus controlling tracking.