发明名称 |
OPTICAL HEAD AND OPTICAL MEMORY DEVICE |
摘要 |
<p>A small and inexpensive optical head for detecting a recorded signal, a focusing error signal and a tracking error signal, and an optical memory device utilizing the optical head. A diffraction device (103) is provided having two chirped grating regions (103A, 103B) for dividing a light beam from an optical recording medium (105) and directing the divided beams toward four band-shaped photoelectric transducers (106) and an astigmatism generator formed by the diffraction means (103) and a positive lens (102). The four photoelectric transducers are positioned in a plane inclined with respect to the optical axis of zero-order diffraction light, and the longitudinal axes of each of the band-shaped photoelectric transducers are radially arranged relative to the optical axis. <IMAGE></p> |
申请公布号 |
EP0467216(A3) |
申请公布日期 |
1992.09.30 |
申请号 |
EP19910111524 |
申请日期 |
1991.07.10 |
申请人 |
SEIKO EPSON CORPORATION |
发明人 |
YOKOYAMA, OSAMU;YONEKUBO, MASATOSHI;IWANO, HIDEAKI;SAKATA, HIDEFUMI;TAKEDA, TAKASHI;SEKI, TETSUYA;KOGURE, SHIGERU |
分类号 |
G11B7/09;G11B7/12;G11B7/13;G11B7/135;G11B11/10;G11B11/105;(IPC1-7):G11B7/12 |
主分类号 |
G11B7/09 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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