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:
May. 21, 2013
Filed:
Jan. 05, 2011
Tsutomu Ishimoto, Tokyo, JP;
Toshihiro Horigome, Kanagawa, JP;
Tsutomu Ishimoto, Tokyo, JP;
Toshihiro Horigome, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An optical drive device includes first and second light sources, an objective lens configured to receive a first light emitted from the first light source and a second light emitted from the second light source and to irradiate both the first light and the second light to an optical disc recording medium, a first focus mechanism configured to drive the objective lens in a focus direction, a second focus mechanism configured to change collimation of the second light incident to the objective lens and changing the focusing position of the second light independently of the first light, a first focus servo control unit configured to drive the first focus mechanism, an error signal subtraction unit configured to subtract the first focus error signal from a second focus error signal, and a second focus servo control unit configured to drive the second focus mechanism.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile