光学脉冲磁场传感测量中线双折射的补偿

Compensation methods for linear birefringence in optical magnetic field sensor

线双折射是制约光学磁场传感器实用化的重要因素之一。为降低线双折射对光学磁场传感器稳定性和输出精度的影响,提出了光路补偿和电路补偿两种方案。光路补偿中使用一对光轴正交的磁光晶体材料作为传感元件,利用琼斯矩阵进行了理论推导,并进行了仿真验证。电路补偿适用于线双折射较大的情况,在交、直流分量中引入修正因子再进行信号处理,仿真计算得到修正因子的最佳值。结果表明,提出的两种方案均能提高输出线性度,改善系统输出误差。

In order to reduce the influence of linear birefringence on optical magnetic field sensor, an optical compensation method and a circuit compensation method were proposed. A pair of crystals with an azimuth angle of 90 degree in optical axis was used in optical compensation. The theoretical deduction was done with Jones matrix. In circuit compensation the amendatory factor was introduced in DC and AC components and the optimal amendatory factor was gained by computation. The results show that the proposed methods can significantly decrease the errors and improve the stability of the system.