发明申请
- 专利标题: Optical pickup and optical data processing apparatus
- 专利标题(中): 光学拾取和光学数据处理装置
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申请号: US10878343申请日: 2004-06-29
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公开(公告)号: US20050025028A1公开(公告)日: 2005-02-03
- 发明人: Hideaki Hirai , Toshimichi Nasukawa , Kazuhiro Umeki
- 申请人: Hideaki Hirai , Toshimichi Nasukawa , Kazuhiro Umeki
- 优先权: JP2003-190596 20030702
- 主分类号: G02B5/18
- IPC分类号: G02B5/18 ; G02B3/08 ; G02B5/30 ; G11B7/00 ; G11B7/125 ; G11B7/135 ; G11B11/00
摘要:
An optical pickup is disclosed that includes a simplified phase correction element enabling sufficient correction of spherical aberration and realization of compatibility with blue-light, DVD-type and CD-type optical recording media with a two-stage numerical aperture switching operation. The phase correction element includes a phase shifting part and a diffraction part superposed on the phase shifting part. The phase shifting part has stepwise concentric circular regions including more than two stages. The diffraction part includes periodically arranged projecting and depressed portions formed on the phase shifting part. The phase shifting part suppresses spherical aberration related to red light used for a DVD-type optical recording medium when the object lens is optimized relative to blue light used for a blue-light optical recording medium. The diffraction part sets a most appropriate NA to each of the blue-light, DVD-type and the CD-type optical recording media by switching the numerical aperture.
公开/授权文献
- US07502300B2 Optical pickup and optical data processing apparatus 公开/授权日:2009-03-10
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