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. 20, 2006
Filed:
Nov. 19, 2002
Norio Fukasawa, Kanagawa, JP;
Junichi Suzuki, Kanagawa, JP;
Kiyoshi Toyota, Tokyo, JP;
Tetsu Tanaka, Tokyo, JP;
Takeshi Kubo, Kanagawa, JP;
Masahiro Saito, Kanagawa, JP;
Satoru Ishii, Chiba, JP;
Norio Fukasawa, Kanagawa, JP;
Junichi Suzuki, Kanagawa, JP;
Kiyoshi Toyota, Tokyo, JP;
Tetsu Tanaka, Tokyo, JP;
Takeshi Kubo, Kanagawa, JP;
Masahiro Saito, Kanagawa, JP;
Satoru Ishii, Chiba, JP;
Sony Corporation, , JP;
Abstract
An optical pickup device is provided which includes a first diffraction grating () that splits a light beam emitted from a light-emitting/-detecting element () into a zero-order light beam and positive and negative first-order light beams, a second diffraction grating () that diffracts return light from an optical disk () for traveling along a light path separate from that of the outgoing light, and a third diffraction grating () that corrects the deviation of the light path by diffracting the positive first-order light beam diffracted by the second diffraction grating (). The light-emitting/-detecting element () provides a focusing error signal FE by detecting the negative first-order light beam, and a tracking error signal by detecting return portions of the positive and negative first-order light beams from the first diffraction grating ().