Heterodyne grating interferometer displacement measurement system

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United States of America Patent

PATENT NO 9879979
SERIAL NO

14441821

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Abstract

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A displacement measurement system of heterodyne grating interferometer, comprises a reading head, a measurement grating and an electronic signal processing component. Laser light emitted from the laser tube is collimated, passes through the first polarization spectroscope, and then emits two light beams with an orthogonal polarization direction and an orthogonal propagation direction; the two light beams pass through two acousto-optic modulators and respectively generate two first-order diffraction light beams with different frequencies, which are later divided into reference light and measurement light; two parallel reference light beams form a beat frequency electric signal with positive and negative first-order diffraction measurement light respectively after passing through a measurement signal photo-electric conversion unit; the beat frequency signals are transmitted to the electronic signal processing component for signal processing, thus the output of linear displacement in two directions is realized.

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Patent Owner(s)

Patent OwnerAddress
TSINGHUA UNIVERSITYNO 1 TSINGHUA YUAN HAIDIAN DISTRICT BEIJING 100084 100084

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Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Chen, Longmin Beijing, CN 3 11
Hu, Jinchun Beijing, CN 28 50
Mu, Haihua Beijing, CN 17 35
Wang, Leijie Beijing, CN 29 26
Xu, Dengfeng Beijing, CN 33 310
Yang, Kaiming Beijing, CN 31 58
Yin, Wensheng Beijing, CN 25 65
Zhang, Ming Beijing, CN 891 7236
Zhu, Yu Beijing, CN 384 3919

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