发明授权
- 专利标题： Objective lens and optical head apparatus using the objective lens
- 专利标题（中）： 物镜和使用物镜的光学头装置
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申请号： US570639申请日： 1995-12-11
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公开(公告)号： US5684641A公开(公告)日： 1997-11-04
- 发明人: Yasuhiro Tanaka , Osamu Doi , Kenji Inoue , Jun Murata , Michihiro Yamagata
- 申请人： Yasuhiro Tanaka , Osamu Doi , Kenji Inoue , Jun Murata , Michihiro Yamagata
- 申请人地址： JPX Osaka
- 专利权人： Matsushita Electric Industrial Co., Ltd.
- 当前专利权人： Matsushita Electric Industrial Co., Ltd.
- 当前专利权人地址： JPX Osaka
- 优先权： JPX6-317911 19941221
- 主分类号： G02B13/00
- IPC分类号： G02B13/00 ; G02B3/06 ; G02B13/08 ; G11B7/125 ; G11B7/135 ; G02B3/02 ; G11B7/00
摘要：
In an objective lens for an optical head apparatus for reading or writing an information on a recording medium such as optical disc, astigmatism is added on axial wavefront aberration so that off-axis astigmatism is to be cancelled by the axial astigmatism. At least one surface of the objective lens is a toric or cylindrical surface, and a standard deviation of astigmatism component of axial wavefront aberration is defined as Wa is to be restricted in a range of 0
公开/授权文献
- USD331506S Night stand 公开/授权日：1992-12-08