发明名称 |
ERROR DETECTION |
摘要 |
An opto-electronic focussing-error detection arrangement is described for the detection of a deviation between a radiation reflecting surface and the plane of focussing of an objective system. In the path of the beam which is reflected by the surface a beam-splitting element is disposed and behind said element two radiation-sensitive detectors are arranged which are each associated with one of the subbeams formed by the beam-splitting element. The detectors are grating-shaped detectors and are effectively divided into two detector sections by selection devices, the bounding line being adjustable. A focussing error signal is obtained which is highly independent of a positional error of the radiation-sensitive detection system relative to the beam axis. |
申请公布号 |
AU4598779(A) |
申请公布日期 |
1979.10.18 |
申请号 |
AU19790045987 |
申请日期 |
1979.04.10 |
申请人 |
PHILIPS' GLOEILAMPENFABRIEKEN, N.V. |
发明人 |
GIJSBERTUS BOUWHUIS;TEUNIS JOHANNES HAZENDONK |
分类号 |
G02B7/34;G02B7/28;G11B7/09;G11B7/1359;G11B7/1381 |
主分类号 |
G02B7/34 |
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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