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:
Nov. 07, 2006

Filed:

Jul. 26, 2004
Applicants:

Minoru Yonezawa, Musashino, JP;

Hideaki Ohsawa, Yokohama, JP;

Inventors:

Minoru Yonezawa, Musashino, JP;

Hideaki Ohsawa, Yokohama, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01); G11B 7/095 (2006.01);
U.S. Cl.
CPC ...
Abstract

An optical disk apparatus has a first optical system having an objective lens with a first NA, a second optical system having an objective lens with a second NA lower than the first NA, an addition mechanism for adding focus error signals detected by the first and second optical systems, and an alignment mechanism for aligning the objective lens in accordance with the addition result of the addition mechanism.


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