发明名称 |
DOUBLE PASS INTERFEROMETRIC ENCODER SYSTEM |
摘要 |
An encoder head includes one or more components arranged to: i) direct a first incident beam to the diffractive encoder scale at a first incident angle with respect to the encoder scale; ii) receive a first return beam from the encoder scale at a first return angle, the first return angle being different from the first incident angle; iii) redirect the first return beam to the encoder scale as a second incident beam at a second incident angle; and iv) receive a second return beam back from the encoder scale at a second return angle, the second return angle being different from the second incident angle, in which a difference between the first incident angle and second incident angle is less than a difference between the first incident angle and the first return angle and less than a difference between the second incident angle and the second return angle. |
申请公布号 |
EP2776792(A4) |
申请公布日期 |
2015.08.12 |
申请号 |
EP20120847106 |
申请日期 |
2012.11.08 |
申请人 |
ZYGO CORPORATION |
发明人 |
DE GROOT, PETER;LIESENER, JAN |
分类号 |
G01D5/26;G01D5/353;G01D5/36;G01D5/38;G03F7/20;H01L21/68 |
主分类号 |
G01D5/26 |
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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