发明申请
- 专利标题: Optical Pickup
- 专利标题(中): 光学拾音
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申请号: US13779802申请日: 2013-02-28
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公开(公告)号: US20130176840A1公开(公告)日: 2013-07-11
- 发明人: Hiromi Kita , Tomoto Kawamura , Toshiteru Nakamura
- 申请人: Hiromi Kita , Tomoto Kawamura , Toshiteru Nakamura
- 申请人地址: JP Iwate
- 专利权人: Hitachi Media Electronics Co., Ltd
- 当前专利权人: Hitachi Media Electronics Co., Ltd
- 当前专利权人地址: JP Iwate
- 优先权: JP2010-012753 20100125
- 主分类号: G11B21/10
- IPC分类号: G11B21/10
摘要:
An optical pickup includes a light source, an objective lens, a diffraction grating that divides an optical beam reflected from a predetermined information layer, into a plurality of optical beams, and a detector having a plurality of photo-receivers to receive a plurality of optical beams. The diffraction grating has a predetermined region for dividing from a signal light beam a region including a central portion of a spot which the signal light beam will form on the diffraction grating. A distance from a central section of the detector to that of a spot center photo-receiver on the detector, the spot center photo-receiver being provided to receive the optical beams formed by division in a predetermined region of the diffraction grating, is equal to or greater than a spot radius of the unwanted light beams entering the predetermined region of the diffraction grating, on the detector.