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.:
Date of Patent:
Oct. 09, 2007
Filed:
Nov. 12, 2004
Applicant:
Hideaki Funakoshi, Osaka, JP;
Inventor:
Hideaki Funakoshi, Osaka, JP;
Assignee:
Funai Electric Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A finite optical system that a laser beam from a light source is allowed to be directly incident on an objective lens without passing a collimate lens is employed. The reference position of the objective lens is set so that converged light from the objective lens forms a focal point on a recording layer remoter from the light source of two recording layers in an optical disk. The objective lens moves in a direction of the light source side from the reference position to perform a focusing operation and read information recorded on the recording layer nearer to the light source.