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.

Date of Patent:
Aug. 02, 2005

Filed:

Mar. 12, 2003
Applicants:

Takashi Kishimoto, Nara, JP;

Takeharu Yamamoto, Takatsuki, JP;

Yoshihiro Kanda, Osaka, JP;

Jun Kikuchi, Takatsuki, JP;

Inventors:

Takashi Kishimoto, Nara, JP;

Takeharu Yamamoto, Takatsuki, JP;

Yoshihiro Kanda, Osaka, JP;

Jun Kikuchi, Takatsuki, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B007/00 ;
U.S. Cl.
CPC ...
Abstract

An optical disc drive includes: an optical head with an actuator and a photodetector; a tracking driver outputting a drive signal to the actuator; a first tracking error signal generator for generating a first tracking error signal based on an output signal of the photodetector; first and second lens position control sections for respectively outputting first and second lens position control signals to the tracking driver; and a selector for selectively supplying the first tracking error signal to the first or second lens position control section according to a moving velocity of the optical head during a seek operation. The first lens position control signal is obtained by extracting signal components, of which the frequencies are equal to or lower than a predetermined frequency, from the first tracking error signal. The second lens position control signal is obtained by extracting DC components of the first tracking error signal at on-track points thereof.


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