Modeling and Experimental Study on Magneto-Optical Modulation Based on Rectangular Wave and Sine Wave

The sine wave magneto-optical modulation and the rectangular wave magneto-optical modulation are investigated in this paper. It was shown that Lissajou figure of the sine wave magneto-optical modulation is a curve, which makes it difficult to estimate the extinction position, and output wave is easily distorted because of the instability of signal. The magneto-optical modulation based on rectangular wave can reduce this impact effectively. The extinction position can be judged by the discrete points of Lissajou figure, and the accuracy is also increased in this method. In our experiment , the precision could exceed 0.001°.