发明名称 |
Holographic optical device |
摘要 |
A light beam emitted from a semiconductor laser element is collimated by a collimating lens, and is applied to an optical disk through a polarizing holographic beam splitter, a lambda /4 plate and an objective lens, a light beam reflected by the optical disk is applied to the polarizing holographic beam splitter and is diffracted. Diffracted light beams of +1st order and -1st order are applied to two photodetectors, and a focus error signal and a tracking error signal are obtained on the basis of the diffracted light beam of +1st order and an information signal is obtained on the basis of the diffracted light beam of -1st order.
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申请公布号 |
US5748599(A) |
申请公布日期 |
1998.05.05 |
申请号 |
US19970785542 |
申请日期 |
1997.01.17 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
YAMAMOTO, HIROAKI;SAIMI, TETSUO;NISHINO, SEIJI;KOMMA, YOSHIAKI;WADA, HIDENORI |
分类号 |
G11B7/09;G11B7/12;G11B7/135;(IPC1-7):G11B7/00 |
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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