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:
Dec. 11, 2012
Filed:
Jul. 20, 2011
Kenji Nagatomi, Kaizu, JP;
Shinsei Kasahara, Ota, JP;
Shigeharu Shirane, Kumagaya, JP;
Masayuki Yoshie, Oizumi-Machi, JP;
Kenji Nagatomi, Kaizu, JP;
Shinsei Kasahara, Ota, JP;
Shigeharu Shirane, Kumagaya, JP;
Masayuki Yoshie, Oizumi-Machi, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
An optical pickup device has an astigmatism element which imparts astigmatism to reflected light of laser light reflected on a recording layer, and a spectral element into which the reflected light is entered, and which separates the reflected light. The spectral element is divided into six second areas by a straight line in parallel to a first direction, a straight line in parallel to a second direction, and a first area having a predetermined width and formed along a straight line in parallel to a third direction inclined from the first direction by 45 degrees. The spectral element is configured to guide the reflected light passing through the six second areas to corresponding sensors on a photodetector while making propagating directions of the reflected light different from each other, and to avoid guiding the reflected light entered into the first area to the sensors.