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:
Apr. 29, 2008
Filed:
Dec. 06, 2004
Applicants:
Fumitomo Yamasaki, Nara, JP;
Takuya Wada, Kyoto, JP;
Hideki Aikoh, Osaka, JP;
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
In an optical head for performing the reproduction or recording of information for two or more types of different optical disks, the damage caused to an optical disk or an objective lens by collision between the optical disk and the objective lens is avoided. An optical heads device for reproducing or recording two or more types of information recording mediums different from each other comprises a first optical system, a second optical system, and a control unit for avoiding the collision between an optical disk and a second objective lens when a first optical system is in operation.