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:
Sep. 26, 2000
Filed:
Aug. 07, 1998
Yuichi Takei, Nagano, JP;
Kazuo Kobayashi, Nagano, JP;
Sankyo Seiki Mfg. Co., Ltd., Nagano-ken, JP;
Abstract
An optical assembly comprises a light emitting device and an objective lens for converging light emitted from the light emitting device onto an optical recording medium. A first diffraction grating is included in which a first grating pattern is formed for diffracting said light emitted from the light emitting device to guide it to the objective lens. Also included are a light receiving element and a second diffraction grating in which a second grating pattern is formed for diffracting returning light from the optical recording medium to guide it to the light receiving element. First alignment marks are provided to either the first or second grating for aligning the diffraction grating having the marks with another element.