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:
Jun. 21, 2005
Filed:
Mar. 28, 2001
Kazushi Mori, Hirakata, JP;
Atsushi Tajiri, Mishima-gun, JP;
Toyozo Nishida, Suita, JP;
Yasuaki Inoue, Nagaokakyo, JP;
Yasuhiro Ueda, Hirakata, JP;
Masayuki Shono, Hirakata, JP;
Minoru Sawada, Yawata, JP;
Kazushi Mori, Hirakata, JP;
Atsushi Tajiri, Mishima-gun, JP;
Toyozo Nishida, Suita, JP;
Yasuaki Inoue, Nagaokakyo, JP;
Yasuhiro Ueda, Hirakata, JP;
Masayuki Shono, Hirakata, JP;
Minoru Sawada, Yawata, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Abstract
A six-segment holographic surface is divided into regions by dividing lines. A four-segment photodetection part is divided into four photodetection parts equal in area by a section line substantially parallel to the radial direction of an optical disk and a section line orthogonal thereto. A main light beam diffracted in the regions of the six-segment holographic surface are condensed as spots at positions apart from each other on opposite sides on a section line of the four photodetection parts, and the main beam diffracted in the regions is condensed as spots in the center of the photodetection parts of the four-segment photodetection part.