- 专利标题: Three-DOF heterodyne grating interferometer displacement measurement system
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申请号: US14900111申请日: 2014-06-05
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公开(公告)号: US09903704B2公开(公告)日: 2018-02-27
- 发明人: Yu Zhu , Leijie Wang , Ming Zhang , Zhao Liu , Rong Cheng , Kaiming Yang , Dengfeng Xu , Weinan Ye , Li Zhang , Yanpo Zhao , Huichao Qin , Li Tian , Jin Zhang , Wensheng Yin , Haihua Mu , Jinchun Hu
- 申请人: TSINGHUA UNIVERSITY
- 申请人地址: CN Beijing
- 专利权人: TSINGHUA UNIVERSITY
- 当前专利权人: TSINGHUA UNIVERSITY
- 当前专利权人地址: CN Beijing
- 优先权: CN201310243132 20130619
- 国际申请: PCT/CN2014/079227 WO 20140605
- 国际公布: WO2014/201951 WO 20141224
- 主分类号: G01B9/02
- IPC分类号: G01B9/02 ; G01B11/14
摘要:
A three-DOF (Degree of Freedom) heterodyne grating interferometer displacement measurement system comprises a dual-frequency laser, a grating interferometer, a measurement grating, receivers and an electronic signal processing component; the grating interferometer comprises a polarizing beam splitter, a reference grating and dioptric elements; the measurement system realizes displacement measurement on the basis of grating diffraction, the optical Doppler Effect and the optical beat frequency principle. Three linear displacements can be output by the system when the grating interferometer and the measurement grating perform a three-DOF linear relative motion. The measurement system can reach sub-nanometer and higher resolution and precision, and can simultaneously measure three linear displacements. The measurement system has the advantages of being environmentally insensitive, high in measurement precision, small in size, light in weight, and is capable of improving the overall performances of an ultra-precision stage of a lithography machine as a position measurement system for this stage.