为了研究手性液晶传输距离的变化对入射激光偏振态的影响，通过连续改变入射激光在手型液晶中的传输距离，楔型手性液晶盒可以有效地改变入射激光束的偏振状态，使之从初始的线偏振状态变成了近似的圆偏振光，且同初始的入射偏振方向无关。理论计算和实验结果表明，该方法可用于液晶退偏器的理论分析和设计。

The polarization state of input laser induced by the change of transmitted distance is studied. From theory analysis and experiment data,the polarization of input laser can be changed by wedge cholesteric liquid crystal cell through continual adjusting the transmitted distance. The input linearly polarized laser is changed to circularly polarized light. This change is not depent on the first polarize angle. The results show that wedge cholesteric liquid crystal cell can be used in the design and analysis of liquid crystal depolarizer.