In order to solve the problem of weak signal, messy waveform at zero-point and difficult demodulation, when the optical Doppler vibrometer in the long-distance non-contact measurement, in this paper, a new type of optical fiber collimation system is proposed. The system mainly uses an augmented beam shaping system at the end of a small C-lens optical fiber collimator and the Gaussian beam is collimated and optimized by ZEMAX software. Through the coupling test of finished product of optical fiber collimation system, and compared with the signal coupling efficiency of C-lens collimator. The experimental results show that the improved collimation system can meet the working distance of 2 meters, and the coupling efficiency of space return optical up to 6.3%, which greatly enhances the Doppler signal contrast and improves the long-distance optical fiber Doppler vibration measurement accuracy.
Long-distance optical fiber collimation system for Doppler vibrometer
First published at:Feb 22, 2018
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National Natural Science Foundation of China (617041) and Shaanxi Provincial Key Laboratory of Optoelectronic Testing and Instrumentation Technology Open Fund (2015SZSJ-60-3)
Get Citation: Liu J, Wang W, Chen H B, et al. Long-distance optical fiber collimation system for Doppler vibrometer[J]. Opto-Electronic Engineering, 2018, 45(2): 170621.
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