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. 25, 1998
Filed:
Apr. 07, 1997
Kenzo Shodo, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
An optical piece reproduces information from a spiral track of a disk. The pickup device includes the first to sixth photoelectric conversion devices. The first and fourth devices are disposed next to each other along the direction of the track of the disk; the second and third devices are disposed next to each other along the direction of the track. The first and second devices are disposed next to each other along the direction perpendicular to the track direction; the third and fourth devices are disposed next to each other along the direction perpendicular to the track direction. The fifth and sixth devices are disposed on both sides of the unit composed of the first to fourth devices along the track direction. The outputs of the first and third devices are added. The outputs of the second and fourth devices are added. The outputs of the fifth and sixth devices are subtracted from each other. The added and subtracted signals are outputted via output terminals.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile