US 12,460,917 B2
Interferometer displacement measurement system and method
Guohua Sun, Beijing (CN); Xiaoliang Gao, Beijing (CN); and Lei Xu, Beijing (CN)
Assigned to BEIJING U-PRECISION TECH CO., LTD., Beijing (CN); and Beijing United Victory Precision Technology Co., Ltd., Beijing (CN)
Appl. No. 18/037,655
Filed by BEIJING U-PRECISION TECH CO., LTD., Beijing (CN); and Beijing United Victory Precision Technology Co., Ltd., Beijing (CN)
PCT Filed Oct. 22, 2021, PCT No. PCT/CN2021/125623
§ 371(c)(1), (2) Date May 18, 2023,
PCT Pub. No. WO2022/105533, PCT Pub. Date May 27, 2022.
Claims priority of application No. 202011293860.0 (CN), filed on Nov. 18, 2020.
Prior Publication US 2023/0417532 A1, Dec. 28, 2023
Int. Cl. G01B 9/02001 (2022.01); G01B 9/02055 (2022.01); G01B 11/14 (2006.01)
CPC G01B 9/02001 (2013.01) [G01B 9/02077 (2013.01); G01B 11/14 (2013.01); G01B 2290/70 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An interferometer displacement measurement system comprising:
a first laser light source for emitting measurement light;
a first polarization splitting prism, a first photoeletric detector, a first ¼ wave plate, a first splitting prism, an optical waveguide component and a reflector disposed on one side of the first laser light source sequentially, wherein an object to be detected is fixed on the reflector;
a second laser light source for emitting reference light; and
a second polarization splitting prism, a second photoeletric detector, a second ¼ wave plate, a second splitting prism and a reflecting mirror disposed on one side of the second laser light source sequentially, wherein the reflecting mirror is attached to the second splitting prism side,
wherein the measurement light is processed by the first polarization splitting prism, the first ¼ wave plate, the first splitting prism, the optical waveguide component and the reflector, and then is returned to the first photoeletric detector and the second photoeletric detector,
wherein the reference light is processed by the second polarization splitting prism, the second ¼ wave plate, the second splitting prism and the reflecting mirror, and then is returned to the first photoeletric detector and the second photoeletric detector,
wherein the first photoeletric detector generates a measurement signal according to the processed measurement light and the processed reference light, and the second photoeletric detector generates a reference signal according to the processed measurement light and the processed reference light,
wherein displacement information of the object to be detected is determined according to the measurement signal and the reference signal,
wherein the optical waveguide component comprises: a lens fixing element; a first plano-convex lens and a second plano-convex lens disposed within the lens fixing element; and a waveguide fiber and a reflective film positioned between the first plano-convex lens and the second plano-convex lens,
wherein the lens fixing element has a barrel shape and includes a wall between the first plano-convex lens and the second plano-convex lens,
wherein the lens fixing element is made of glass, and the reflective film is attached to a right surface of the wall of the lens fixing element adjacent to the reflector,
wherein a focal length of the first plano-convex lens is a first focal length, and a focal length of the second plano-convex lens is a second focal length,
wherein the waveguide fiber passes through the wall with opposite end surfaces thereof respectively flush with the left surface and the right surface of the wall of the lens fixing element, and
wherein a distance between the first plano-convex lens and the left surface of the wall of the lens fixing element is equal to the first focal length, and a distance from the second plano-convex lens to the right surface of the wall of the lens fixing element is equal to the second focal length.