Abstract

A sensing system is proposed for quantitative measurement of large-range dynamic nanostrain based on a phase-sensitive optical time domain reflectometer, where the coherent detection and $I/Q$ demodulation methods are employed to demodulate both the phase and the amplitude of the Rayleigh scattering light in real time. A nanopositioning translation stage is utilized to apply precise nanostrain to fiber. By measuring phase differences between two adjacent sections, the quantitative nanostrain with a large measurement range is demonstrated; this is also a method to measure the strain parameter of refractive index. For the Panda polarization-maintaining fiber under test in the experiment, the strain parameter of phase difference is measured to be $8.714\mathrm{mrad}/(\mathrm{n\epsilon }·\mathrm{m})$, while the strain parameter of refractive index is measured to be $-0.3751{\epsilon }^{-1}$. As a proof of the concept, the dynamic strain sensing with a range of 10–1000 nε is experimentally demonstrated, and the strain resolution is 1 or 2 $\mathrm{n\epsilon }$, corresponding to 5 or 2.5 m spatial resolution, respectively. The experimental measurement also shows a triangular wave with a 12-Hz vibrating frequency and a 100-nε strain amplitude as well as a 188-Hz resonant signal of the tensile section.

© 2016 Optical Society of America

Distributed dynamic strain measurement using optical frequency-domain reflectometry

Da-Peng Zhou, Liang Chen, and Xiaoyi Bao
Appl. Opt. 55(24) 6735-6739 (2016)

Enhanced range of the dynamic strain measurement in phase-sensitive OTDR with tunable sensitivity

Haijun He, Lianshan Yan, Heng Qian, Xinpu Zhang, Bin Luo, and Wei Pan
Opt. Express 28(1) 226-237 (2020)

High spatial resolution distributed fiber system for multi-parameter sensing based on modulated pulses

Jingdong Zhang, Tao Zhu, Huan Zhou, Shihong Huang, Min Liu, and Wei Huang
Opt. Express 24(24) 27482-27493 (2016)

Influences of laser source on phase-sensitivity optical time-domain reflectometer-based distributed intrusion sensor

Xiang Zhong, Chunxi Zhang, Lijing Li, Sheng Liang, Qin Li, Qiying Lü, Xiuxin Ding, and Qiaoyuan Cao
Appl. Opt. 53(21) 4645-4650 (2014)

Image-matching assisted dual-frequency phase-sensitive optical time domain reflectometry

Ba Dexin, Lamessa A. Ayana, Wang Ying, Wang Long, Chu Qi, and Dong Yong kang
Appl. Opt. 60(34) 10632-10637 (2021)