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. 06, 2006
Filed:
Mar. 18, 2003
Masahiko Nishimoto, Osaka, JP;
Shinichi Hamaguchi, Hyogo, JP;
Masahiko Nishimoto, Osaka, JP;
Shinichi Hamaguchi, Hyogo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The optical pickup of this invention includes a diffraction grating for dividing a light beam emitted from a semiconductor laser into a main beam, a precedent sub beam and a subsequent sub beam; a hologram element for dividing reflected light beams of the main beam, the precedent sub beam and the subsequent sub beam from an optical recording medium respectively into first through eighth main beams, first through eighth precedent sub beams and first through eighth subsequent sub beams; a main beam detector for receiving the first through eighth main beams; a precedent sub beam detector for receiving the first through eighth precedent sub beams; and a subsequent sub beam detector for receiving the first through eighth subsequent sub beams.