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:
Jul. 22, 2014
Filed:
Jan. 17, 2012
Hironori Nakahara, Tokyo, JP;
Toshiya Matozaki, Tokyo, JP;
Nobuo Takeshita, Tokyo, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
An optical pickup device includes a laser light source, a collimating optical systemfor converting laser light to parallel light, a focusing optical systemfor focusing the parallel light onto an optical disc, a light detection unit for receiving returning light returning by reflection of the focused light from the optical discand outputting a detection signal, and a reflecting mirrordisposed between the collimating optical system and the focusing optical system. The reflecting mirrorhas a reflective surface including three regions having different reflectances. The central region on the reflecting surface meets the other two regions, at positions illuminated by the light focused by the light focusing optical system, in boundary lines that are parallel to a radial direction on the optical disc. The reflectance of the central region is lower than the reflectances of the other two regions.