Linear birefringence and imperfect quarter wave plate effects on optic-fiber current sensor

The scale factor of optic-fiber current sensor is nonlinearized because of the linear birefringence and the imperfection of quarter wave plate (QWP). In this paper, we analyze the effects of birefringence and show that modified scale factor performs better by using Faraday rotate mirror (FRM) and harmonic division method. The scale factor error associated with integrating imperfect quarter wave plate is also analyzed. Moreover, a certain linear birefringence may be helpful to compensate for deviation of QWP's alignment.