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. 24, 2010
Filed:
Apr. 19, 2005
Kenji Nagatomi, Gifu, JP;
Seiji Kajiyama, Gifu, JP;
Kenji Nagatomi, Gifu, JP;
Seiji Kajiyama, Gifu, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
An optical pickup device that emits laser light beams having different wavelengths to a recording medium is disclosed. A semiconductor laser includes three laser elements having emitting wavelengths of λ1, λ2, and λ3 (λ1<λ2<λ3), respectively. A plurality of diffraction gratings substantially align optical axes of the laser light beams emitted from the laser elements with one another by diffracting action. The diffraction gratings are separately provided for corresponding laser light beams having wavelengths of λ2 and λ3. Diffracting action for aligning ±n-order diffraction light (n is an integer equal to or greater than 1) of each of the laser light beams having the wavelengths of λ2 and λ3 with an optical axis of a laser light beam having a wavelength of λ1 is provided for the laser light beams having the wavelengths of λ2 and λ3.