为了单独研究起偏器，假设其余器件均为理想器件；以琼斯矩阵作为数学工具，建立了各器件的矩阵表达式，并推导了起偏器不完备影响下的干涉结果表达式。理论分析了起偏器的消光比和其尾纤熔接角度对系统的影响，并做了仿真。结果表明：对于闭环处理的系统来说，选择合适参数的起偏器并做好尾纤的熔接工艺，可减小起偏器的不完备对系统造成的影响。这对光路误差的分析和结构的改进有一定的理论意义。

Polarizer is one of the important polarized components of reflecting fiber-optic current transducer, but the impact of its imperfection has not been presented so far. This paper studied the polarizer independently provided that the rest devices were ideal. Then Jones matrix was employed to establish the matrix expression of every device and the expression of interference results of the imperfect polarizer was derived. The influence of extinction ratio and the pigtail splice point of the polarizer on reflecting fiber-optic current transducer was analyzed and the simulation was carried out. The result indicated that in the closed-loop process, the polarizer with an appropriate parameter and a fine fusion splicing of the pigtail could reduce the impact of the imperfection of polarizer on the whole system. This study can be used for the analysis of light path error and the improvement of transducer structure.