发明名称 |
Inclination of an objective lens in an optical information system |
摘要 |
A detecting apparatus which detects an inclination of an objective lens relative to a reference surface is provided. The objective lens is part of an optical data recording and reproducing apparatus in which data is optically recorded on and reproduced from a recording medium which is placed parallel to the reference surface. The apparatus includes a transparent parallel plate which is opposite the objective lens, parallel to the reference surface, and made of a material that is substantially optically equivalent to a transparent material of the recording medium. The apparatus further includes a reflecting mechanism for reflecting coherent light which has passed through the objective lens and the transparent parallel plate back towards the transparent parallel plate and the objective lens, and a beam splitting mechanism for splitting the coherent light into a first beam and a second beam. The apparatus further includes a wavefront rotating mechanism for rotating the first beam and the second beam about an optical axis in a manner such that the first beam and the second beam are rotated through 180 degrees with respect to one another, and a mechanism for superposing the first beam and the second beam to produce an optical interference.
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申请公布号 |
US5553052(A) |
申请公布日期 |
1996.09.03 |
申请号 |
US19940204655 |
申请日期 |
1994.08.02 |
申请人 |
ASAHI KOGAKU KOGYO KABUSHIKI KAISHA |
发明人 |
OONO, MASAHIRO;KONNO, HISASHI;KASE, TOSHIYUKI;HAYASHI, KATSUKI;NISHIKAWA, HIROSHI |
分类号 |
G11B7/095;G11B7/22;G11B11/105;(IPC1-7):G11B7/00;G02B7/00 |
主分类号 |
G11B7/095 |
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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