Abstract

The existence of periodic nonlinear error restricts the performance of the homodyne laser vibrometer in sub-fringe amplitude vibration measurement. A homodyne laser vibrometer with nanoscale-amplitude detectability by using a liquid crystal variable retarder (LCVR) is proposed. The LCVR introduces an extra variation of optical path difference larger than the laser wavelength to acquire a full ellipse so that the nonlinearity correction parameters could be pre-extracted. The experiments showed that the nonlinear error could be well suppressed with the correction process based on the pre-extracted parameters, and the detectable minimum amplitude is less than 1 nm. In addition, measurement of vibration with the reflectivity of measured targets down to 0.048% was achieved with an automatic-gain-control module.

© 2022 Optica Publishing Group

Homodyne laser vibrometer capable of detecting nanometer displacements accurately by using optical shutters

JingHao Zhu, Pengcheng Hu, and JiuBin Tan
Appl. Opt. 54(34) 10196-10199 (2015)

Dynamic nonlinearity errors in laser Doppler vibrometer measurements induced by environmental vibration and error correction

Lu Cheng, Xu Ziyi, Liu Guodong, Liu Bingguo, Chen Fengdong, Gan Yu, and Lu Binghui
Opt. Express 30(17) 30705-30717 (2022)

Homodyne laser Doppler vibrometer on silicon-on-insulator with integrated 90 degree optical hybrids

Yanlu Li and Roel Baets
Opt. Express 21(11) 13342-13350 (2013)

Real-time acquisition and enhancement of remote acoustic signals by a free-space monostatic homodyne laser Doppler vibrometer

Yanan Zhi, Yu Zou, Kehan Tian, and JianFeng Sun
Appl. Opt. 62(2) 298-313 (2023)

Multipoint laser vibrometer for modal analysis

William N. MacPherson, Mark Reeves, David P. Towers, Andrew J. Moore, Julian D. C. Jones, Martin Dale, and Craig Edwards
Appl. Opt. 46(16) 3126-3132 (2007)