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 7436742 B1

PDF
Full Text
Expired
Date of Patent:
Oct. 14, 2008

Filed:

Oct. 27, 2004
Applicant:

Naoharu Yanagawa, Saitama, JP;

Inventor:

Naoharu Yanagawa, Saitama, JP;

Assignee:

Pioneer Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/00 (2006.01);
U.S. Cl.
CPC ...
Abstract

An optical recording device includes an optical pickup, an asymmetry detection circuit, and a microcomputer. The optical pickup corrects an aberration of an object lens based on an aberration correction value using a liquid crystal panel in the optical pickup, irradiates a laser beam of multiple stages of recording powers on an optical disk to form marks, and then reproduces the formed marks with a reproduction power. The asymmetry detection circuit detects amplitudes of RF signals of the marks reproduced by the optical pickup, calculates amplitude central values such that asymmetry takes a predetermined value, and determines an optimum recording power. The microcomputer performs spherical aberration correction to change a spherical aberration correction value from an initial value such that the optimum recording power takes a minimum value.


Find Patent Forward Citations

Yanagawa, Naoharu. (2008). Optical recording device and aberration correction method (U.S. Patent No. 7436742). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/7436742

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

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