Tsinghua University

Yizhou Xia

Ming Lei Zhang

Xin Li

Yu Zhu

Leijie Wang

Weinan Ye

Fuzhong Yang

A five-degree-of-freedom heterodyne grating interferometry system, comprising a single frequency laser device () and an acousto-optic modulator (); the single frequency laser device () emits a single frequency laser, and the single frequency laser is coupled by optical fiber and, after being split, enters the acousto-optic modulator () to obtain two linearly polarized lights of different frequencies, one being a reference light, and one being a measurement light; an interferometer lens group () and a measurement grating (), used for forming the reference light and the measurement light into a measurement interference signal and a compensation interference signal; and multiple optical fiber bundles (), respectively receiving the measurement interference signal and the compensation interference signal, each optical fiber bundle () having multiple multimode optical fibers respectively receiving signals at different positions on the same plane. The present measurement system has the advantages of high measurement precision, a large measurement range, not being sensitive to temperature drift, and small overall size, and can be used as a photoetching machine ultra-precision workpiece table position measurement system.

Growing community of inventors

Beijing, China

Yizhou Xia