公开(公告)号：US11733026B2

公开(公告)日：2023-08-22

申请号：US17681148

申请日：2022-02-25

Applicant: Harbin Institute of Technology

Inventor： Liang Yu ,  Pengcheng Hu ,  Xionglei Lin ,  Xiaobo Su

IPC: G01B9/02 ,  G01B11/00 ,  G01B11/26

CPC classification number: G01B9/02 ,  G01B9/02083 ,  G01B11/005 ,  G01B11/26

Abstract: 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.

公开(公告)号：US11150077B2

公开(公告)日：2021-10-19

申请号：US17002845

申请日：2020-08-26

Applicant: HARBIN INSTITUTE OF TECHNOLOGY

Inventor： Pengcheng Hu ,  Xiaobo Su ,  Haijin Fu

IPC: G01B9/02 ,  G02B27/12

Abstract: 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.