公开(公告)号：US12247824B1

公开(公告)日：2025-03-11

申请号：US18595312

申请日：2024-03-04

Applicant: HARBIN INSTITUTE OF TECHNOLOGY

Inventor： Haijin Fu ,  Xiaobo Su ,  Liang Yu ,  Pengcheng Hu ,  Zhaochen Pan ,  Zhiwei Wang

IPC: G01B11/14 ,  G01B9/02002

Abstract: 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.

公开(公告)号：US20230384090A1

公开(公告)日：2023-11-30

申请号：US17982033

申请日：2022-11-07

Applicant: Harbin Institute of Technology

Inventor： Pengcheng Hu ,  Liang Yu

IPC: G01C9/06 ,  G01C9/08

CPC classification number: G01C9/06 ,  G01C9/08 ,  G01C2009/066

Abstract: A high-precision dual-axis laser inclinometer based on wavefront homodyne interference and a measuring method are disclosed. The method includes: obtaining a laser signal through a laser light source module, transmitting the laser signal to an integrated sensing module, and generating a wavefront interference signal based on the integrated sensing module; and inputting the wavefront interference signal into a signal processing module for performing high-precision decoupling operation to obtain a horizontal inclination angle measurement result. The measurement resolution is high, the measurement result can be directly traced to the laser wavelength, high-precision dual-axis inclination angle measurement can be realized only by using single-beam measurement light, meanwhile, the laser inclinometer has the advantages of being simple in structure, simple in light path, easy to integrate, beneficial to engineering implementation, and high in cost performance, and the requirement of high-end equipment on the ultra-precision inclinometer is met.

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：US12287198B1

公开(公告)日：2025-04-29

申请号：US18595318

申请日：2024-03-04

Applicant: HARBIN INSTITUTE OF TECHNOLOGY

Inventor： Haijin Fu ,  Xiaobo Su ,  Liang Yu ,  Pengcheng Hu ,  Xizheng Liu ,  Xin Yang

IPC: G01B9/02 ,  G01B9/02001

Abstract: 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.

公开(公告)号：US20220290969A1

公开(公告)日：2022-09-15

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 ,  G01B11/26 ,  G01B11/00

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.