发明名称 |
Focus error detecting apparatus. |
摘要 |
<p>A focus error detecting apparatus is improved by splitting the light detector into three portions (A,B,C), with a first portion (B) located between the second (A) and third (C) portions and being elongated. The elongation prevents an out-of-focus condition, where the detection light spot is elliptically elongated in the elongation direction, from being falsely detected as the focused condition.</p> |
申请公布号 |
EP0282354(A2) |
申请公布日期 |
1988.09.14 |
申请号 |
EP19880302215 |
申请日期 |
1988.03.14 |
申请人 |
PIONEER ELECTRONIC CORPORATION |
发明人 |
MAEDA, TAKANORI C/O PIONEER ELECTRONIC CORPORATION;NOMURA, SUSUMU C/O PIONEER ELECTRONIC CORPORATION |
分类号 |
G02B7/28;G11B7/09;G11B7/13 |
主分类号 |
G02B7/28 |
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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