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.:

US 8068393 B1

PDF
Full Text
Expired
Date of Patent:
Nov. 29, 2011

Filed:

Aug. 07, 2009
Applicant:

Akihiko Doi, Tokyo, JP;

Inventor:

Akihiko Doi, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/09 (2006.01); G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract

An optical disc apparatus includes an emitter which emits a laser beam to a optical disc, a divided photodetector including a first dived portion and a second dived portion disposed in a light path of the reflected beam from the optical disc, and producing a first photodetector signal and a second photodetector signal, a phase difference detector which produces a phase difference signal from a phase difference between the first and the second photodetector signals, an integrator which produces a integral signal from a integration of the phase difference signal, a tracking controller configure to perform tracking control based on the integral signal, and a limiter which limits a signal to be supplied from the divided photodetector to the phase difference detector or a signal to be supplied from the phase difference detector to the integrator based on a detection status of a signal detected by the dived photodetector.


Find Patent Forward Citations

Doi, Akihiko. (2011). Optical disc apparatus including a divided photodetector (U.S. Patent No. 8068393). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/8068393

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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