Li Changsheng
School of Instrument Science and Optoelectronic Engineering, Beihang University, Haidian District, Beijing, China
Appl Opt. 2011 Sep 20;50(27):5315-20. doi: 10.1364/AO.50.005315.
An optical stress sensor is proposed by using a single crystal with both electro-optic and photoelastic effects. Different from previous crystal-based stress sensors, the proposed sensor is based on electro-optic compensation for stress-induced birefringence and does not need an additional quarter-wave plate or modulator, because the stress-sensing element is simultaneously used as an electro-optic compensator. Candidate sensing materials include electro-optic crystals of the 3 m symmetry group and all glass with large Kerr coefficients. A primary experiment has demonstrated that the stress-induced birefringence in lithium niobate crystal can be compensated by its electro-optic birefringence. The proposed stress sensor is compact and low cost, and it is possible to achieve closed-loop stress measurement.
提出了一种利用具有电光效应和光弹性效应的单晶的光学应力传感器。与以往基于晶体的应力传感器不同，该传感器基于对应力诱导双折射的电光补偿，不需要额外的四分之一波片或调制器，因为应力传感元件同时用作电光补偿器。候选传感材料包括3m对称群的电光晶体和具有大克尔系数的全玻璃。初步实验表明，铌酸锂晶体中的应力诱导双折射可以通过其电光双折射来补偿。所提出的应力传感器结构紧凑、成本低，并且有可能实现闭环应力测量。
