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:
Mar. 04, 2003

Filed:

Mar. 08, 2000
Applicant:
Inventors:

Yoshito Asoma, Saitama, JP;

Kiyoshi Toyota, Tokyo, JP;

Noriaki Nishi, Tokyo, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 ;
U.S. Cl.
CPC ...
G11B 7/00 ;
Abstract

A cylindrical lens for generating focussing error signals is formed as one with a portion of an optical component of a transparent material lying on an optical path L that is an optical path of a return light beam from the optical member . This configuration assures a small size while reducing the production cost and improving operational reliability.


Find Patent Forward Citations

Loading…