Harbin Institute of Technology

Xiaobo Su

PengCheng Hu

Liang Yu

Haijin Fu

Xin Yang

Xizheng Liu

Xionglei Lin

Zhiwei Wang

Zhaochen Pan

A heterodyne laser interferometer and a measurement method based on an integrated dual polarization beam-splitting assembly is provided. Technical points: The first polarization beam splitter and the second polarization beam splitter of the integrated dual polarization beam-splitting assembly are arranged in parallel. The first polarization beam splitter is attached with a first polarizer, a third polarizer, and a first quarter-wave plate; The second polarization beam splitter is attached with a second polarizer, a fourth polarizer, and a second quarter-wave plate; The output optical path of the first quarter-wave plate and the second quarter-wave plate is equipped with target mirrors, while the output optical path of the third quarter-wave plate and the fourth quarter-wave plate is equipped with photodetectors. The assembly and adjustment of the present invention is more flexible and reduce the processing difficulty and processing error.

Heterodyne laser interferometer based on integrated dual polarization beam-splitting assembly and measurement method thereof

A heterodyne interferometer and a measurement method based on multi-target opposite displacement measurement are provided, technical points including: An output path of the laser source is sequentially arranged with a first beam splitter and a second beam splitter arranged in parallel on left and right sides, and both of which are polarization beam splitters; a first reflector is arranged above the first beam splitter, a third reflector is arranged on a right side of the second beam splitter, a second plane reflector is arranged in front of the second beam splitter, and a first plane reflector is arranged behind the second beam splitter; the first plane reflector and the second plane reflector jointly constitute a second reflector group; a left side of the first beam splitter is provided with a first photodetector and a second photodetector. The present invention realizes the measurement of relative displacement between opposing objects.

Heterodyne interferometer based on multi-target opposite displacement measurement and measurement method thereof

A single-beam three-degree-of-freedom homodyne laser interferometer based on an array detector. A single-frequency laser beam is input to a Michelson interference structure, the measurement beam and the reference beam perform non-coaxial interference and form a single-beam homodyne interference signal by setting the angle of a reference plane mirror, the array detector is selected to effectively receive the single-beam homodyne interference signal, and finally, three-degree-of-freedom signal linear decoupling on the single-beam homodyne interference signal is achieved through a three-degree-of-freedom decoupling method based on Lissajous ellipse fitting. The laser interferometer does is free of angle decoupling nonlinearity, the period nonlinear error is remarkably reduced, compared with other existing three-degree-of-freedom laser interferometers, the laser interferometer has the advantages of being simple in structure, large in angle measurement range and easy to integrate, and the high-precision requirement of the three-degree-of-freedom laser interferometer for displacement and angle measurement is met.

Single-beam three-degree-of-freedom homodyne laser interferometer based on array detector

Disclosed is a heterodyne laser interferometer based on an integrated secondary beam splitting component, which belongs to the technical field of laser application; the disclosure inputs two beams that are spatially separated and have different frequencies to the heterodyne laser interferometer based on the integrated secondary beam splitting component, wherein the integrated secondary beam splitting component includes two beam splitting surfaces that are spatially perpendicular to each other; and the two beam splitting surfaces are plated with a polarizing beam splitting film or a non-polarizing beam splitting film, and a measurement beam and a reference beam are the same in travel path length in the integrated secondary beam splitting component. The heterodyne laser interferometer of the disclosure significantly reduces periodic nonlinear errors, has the advantages of simple structure, good thermal stability, large tolerance angle and easy integration and assembly compared with other existing heterodyne laser interferometers with spatially separated optical paths, and meets the high-precision and high-resolution requirements of high-end equipment on heterodyne laser interferometry.

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Harbin, China

Xiaobo Su