为了消除入射光的偏振态变化对相干系统的负面影响，一种有效的方法就是对入射光进行退偏处理。利用液晶随着液晶分子取向的偏转，光沿z轴传播的折射率n发生变化的特性，可通过改变外加电压可以任意控制液晶各点的偏振态，从而能够实现任意偏振输出。报道了一种由两片液晶片组合而成的新型单色退偏振器，理论研究了利用液晶的偏振特性对单色光进行退偏原理。实验结果表明，这种退偏振器对入射光偏振方向不敏感，可对任意偏振态或偏振态随时间变化的连续或者脉冲入射单色光进行完全退偏。可用于惯性约束聚变激光驱动器光纤前端系统中以消除偏振变化对系统的影响。

To cancel the negative influence of the polarization variety of the incident light on a coherent system because,one of the effective methods is to depolarize the incident light. Making use of the characteristic of liquid crystal whose refractive indexn along z is various with the deflection orientation of the liquid crystal element,the polarization of the liquid crystal can bearbitrarily controlled by changing the voltage of the liquid crystal and the light can propagate at arbitrary polarization. A new depolarizer composed of two liquid crystal was proposed in the paper. Experimental results show that the liquid crystal depolarizer is insensitive to the polarization state of the incident light and can totally depolarize CW or pulsed monochromatic light with arbitrary polarization states. The depolarizer has the potential to keep the polarization state of the fiber injection laser system of the ICF driver.