Invention Grant
- Patent Title: Optical disc drive and objective lens for the same
- Patent Title (中): 光盘驱动器和物镜相同
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Application No.: US11536004Application Date: 2006-09-28
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Publication No.: US07839752B2Publication Date: 2010-11-23
- Inventor: Daisuke Koreeda , Koichi Maruyama , Shuichi Takeuchi , Yoshiyuki Tashiro
- Applicant: Daisuke Koreeda , Koichi Maruyama , Shuichi Takeuchi , Yoshiyuki Tashiro
- Applicant Address: JP Tokyo
- Assignee: Hoya Corporation
- Current Assignee: Hoya Corporation
- Current Assignee Address: JP Tokyo
- Agency: Greenblum & Bernstein P.L.C.
- Priority: JPP2005-282361 20050928
- Main IPC: G11B7/135
- IPC: G11B7/135

Abstract:
There is provided an optical disc drive for recordation/reproduction for three types of optical discs by selectively using one of three types of light beams. The optical disc drive comprises an objective lens. The objective lens has a step structure which gives an optical path length difference to an incident beam at each step. When the third laser beam passes through the objective lens, the objective lens produces normal diffraction order light converging to a recording surface of the third optical disc and undesired diffraction order light converging to a point deviating from the recording surface of the third optical disc. A distance from a point to which the normal diffraction order light converges to a point to which the undesired diffraction order light converges is larger than or equal to twice a pull-in range of a focus error signal obtained when the third optical disc is used.
Public/Granted literature
- US20070070860A1 OPTICAL DISC DRIVE AND OBJECTIVE LENS FOR THE SAME Public/Granted day:2007-03-29
Information query
IPC分类: