发明名称 |
OPTICAL HEAD |
摘要 |
An optical head comprising a diffracting element having two tracking diffracting regions separated by a division line extending in a direction corresponding to a track direction of a recording medium, and one focusing diffracting region separated from the tracking diffracting regions by a division line extending in a direction corresponding to a radial direction of the recording medium. The optical head further comprises a light receiving element having two tracking light receiving regions for receiving diffracted lights produced in the tracking diffracting regions, and two adjoining focusing light receiving regions for receiving a diffracted light produced in the focusing diffracting region. The diffracted light produced in the focusing diffracting region always has a substantially constant light intensity, even when a tracking error occurs. As a result, an offset can be prevented from occurring in a focus error signal by finely adjusting the diffracting element.
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申请公布号 |
CA2041928(C) |
申请公布日期 |
1996.04.02 |
申请号 |
CA19912041928 |
申请日期 |
1991.05.07 |
申请人 |
SHARP KABUSHIKI KAISHA |
发明人 |
MIYAKE, TAKAHIRO;YOSHIDA, YOSHIO;KURATA, YUKIO;SATO, HIDEAKI |
分类号 |
G11B7/09;G11B7/125;G11B7/13;G11B7/135;(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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