We give qualitative analysis and theory explanation to it according to the laboratory instrument localization, the main factor is the monochromaticity of the light, crystal absorb is the side effect.

• 根据实验仪器本身的局限,我们对此曲线进行了分析并给出了理论上的解释,由此证明了入射光单色性是影响曲线变化的主要因素,材料吸收是次要因素。