基于相位延迟器和双折射棱镜的光学相控阵设计及验证

Design and Validation of the Optical Phased Array by Using Half-Wave LC Retrader and Birefringent Prism

为了实现非机械式大角度光束偏转,设计了一种基于电控相位延迟器与双折射棱镜级联的液晶光学相控阵系统。采用了VirtualLab软件中的相位调制元件,仿真分析了纯相位液晶空间光调制器对光束偏转的效果和光场相位分布图。介绍了半波液晶相位延迟器与双折射棱镜级联结构对角度放大的原理,分析了光束入射角及出射角的影响因素,提出了最优化参数组合方法。通过控制半波液晶相位延迟器的电压可改变入射光束的偏振态,提出了电压控制组合方法。实验结果证明利用电控液晶相位延迟器与双折射棱镜组合可以实现角度放大功能,最大光束偏转角实测为22.3°,该研究结果表明电控液晶相位延迟器可实现光束偏转的切换,在大角度非机械式光束偏转技术中可广泛应用。

In order to realize non-mechanical large-angle beam steering,an LC optical phased array system using phase retarder and birefringent prism is studied.The simulation and analysis of beam steering result and phase distribution by liquid crystal spatial light modulator(LCSLM)is presented,using phase modulator of VirtualLab.The angle magnifier principle of half-wave LC retarder and birefingent prism is introduced.Then the parameters which impact on incidence angle and emergence angle are analyzed,to table the optimized parameter groups.The polarization of incidenceangle can be changed by altering the voltage of half-wave LC retarder,and voltage parameter groups are achieved.The experiment results confirm that phase retarder and birefringent prism are useful.In this paper,the phase retarder controlled by voltage is proved to be able to choose the path of beam,which can be widely used in the non-mechanical large-angle beam steering.