发明授权
- 专利标题： Optical disk system having an objective lens with a numerical aperture related to the thickness of the protective layer
- 专利标题（中）： 具有与保护层的厚度相关的具有数值孔径的物镜的光盘系统
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申请号： US890238申请日： 1997-07-09
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公开(公告)号： US5838656A公开(公告)日： 1998-11-17
- 发明人: Tetsu Watanabe , Yoshio Aoki
- 申请人： Tetsu Watanabe , Yoshio Aoki
- 申请人地址： JPX Tokyo
- 专利权人： Sony Corporation
- 当前专利权人： Sony Corporation
- 当前专利权人地址： JPX Tokyo
- 优先权： JPX2-21210 19900131
- 主分类号： G11B7/0037
- IPC分类号： G11B7/0037 ; G11B7/007 ; G11B7/135 ; G11B7/24 ; G11B11/105
摘要：
A magneto-optical disc system includes a magneto-optical disc 40 with a light-transmitting layer 41, an objective lens 2 for bundling or focusing a laser beam onto a magnetic recording layer 43 of the magneto-optical disc 40 for recording information thereon and/or reproducing information therefrom, and a magnetic field generating unit 9 having a coil pattern 7 arranged on an optical glass element 8. The thickness t.sub.2 of the light-transmitting layer 41 falls within the range of 0.6 to 0.1 mm, and the numerical aperture (NA) of the objective lens 2 falls within the range of 0.55 to 0.70.
公开/授权文献
- US5330877A Photosensitive compositions containing stilbazolium groups 公开/授权日：1994-07-19
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