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:
Aug. 31, 2010
Filed:
Apr. 10, 2006
Tatsuo Itoh, Osaka, JP;
Teruhiro Shiono, Osaka, JP;
Seiji Nishino, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A laser beamreflected by an information layer of a multilayer optical discis reflected and split by reflecting surfacesandto be incident on a photodetector elementas laser beamsand. The laser beamis collected on a light receiving regionfor RF detection to generate an RF signal. The laser beamsare incident on light receiving regionsfor focus detection, and a focus error signal is generated by an SSD method. A laser beamreflected by an information layer adjacent to the above information layer partially transmits through the reflecting surface' to be imaged on a light receiving regionfor tracking detection, and a tracking error signal is generated.