级联液晶偏振光栅的衍射特性分析  

Diffraction Characteristics Analysis of Cascaded Liquid Crystal Polarization Gratings

作　　者：王丽娜 李明秋[1] 王春阳 史红伟[1] 牛启凤 Wang Li'na;Li Mingqiu;Wang Chunyang;Shi Hongwei;Niu Qifeng(College of Electronics and Information Engineering,Changchun University of Science and Technology,Changchun,Jilin 130022,China)

机构地区：[1]长春理工大学电子信息工程学院,吉林长春130022

出　　处：《激光与光电子学进展》2020年第3期80-84,共5页Laser & Optoelectronics Progress

基　　金：吉林省科技发展计划项目(20190302089GX)。

摘　　要：液晶偏振光栅(LCPG)可实现光束非机械偏转,LCPG在实际制备中液晶分子填充不均匀会导致液晶层厚度不均匀,从而使光通过级联LCPGs有效区域的同一位置时的衍射效率降低。为了提高级联LCPGs的衍射效率,基于琼斯矩阵理论分析了驱动电压对LCPG衍射效率的影响,利用三级级联LCPGs构建光束偏转实验装置,通过施加不同驱动电压来测量光斑能量,得到衍射效率随电压的变化关系曲线。实验结果表明,当电压在2.0~2.4V范围内时,+1级衍射效率达到0.80~0.84。Liquid crystal polarization grating(LCPG)can achieve non-mechanical beam steering.During the actual preparation of LCPGs,the filling of liquid crystal molecules is not uniform,resulting in uneven liquid crystal layer thickness,which reduces the diffraction efficiency of light through the same position of the effective region of cascaded LCPG.This study analyzes the influence of driving voltage on the diffraction efficiency of LCPG based on Jones matrix theory to improve the diffraction efficiency of cascaded LCPGs.An experimental device is constructed for beam deflection using a three-stage cascaded LCPGs.The spot energy is measured by applying varying driving voltages,and the relationship between the diffraction efficiency and the voltage is obtained.The experimental results show that the+1st-order diffraction efficiency reaches 0.80-0.84 when the voltage is in the range of 2.0--2.4 V.

关 键 词：光栅 级联液晶偏振光栅 光束偏转 衍射效率 驱动电压 

分 类 号：TN209[电子电信—物理电子学]