基于硅基液晶变焦透镜的相位恢复方法  

Phase Retrieval Method Based on Liquid Crystal on Silicon Tunable-Lens

作　　者：程鸿[1] 吕倩倩[1] 张文君[1] 邓会龙 高要利 

机构地区：[1]安徽大学计算智能与信号处理教育部重点实验室,安徽合肥230039

出　　处：《中国激光》2017年第3期176-182,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61301296;61377006;61501001;61605002;U1201255);安徽省自然科学基金(1608085QF161);安徽省高等学校自然科学研究项目(KJ2016A029;KJ2015A114)

摘　　要：针对传统的基于光强传输方程(TIE)相位恢复方法中需要通过移动待测物体或者CCD以实现光强图像采集所造成的速度慢、精确度低等问题,提出了一种新的基于硅基液晶(LCOS)变焦透镜的相位恢复方法。首先,在LCOS上加载具有不同焦距的透镜相位分布图,使其实现变焦透镜的功能;然后通过本研究所设计的系统在同一成像平面上采集不同散焦距离的光强图像;最后求解TIE从而得到相位信息。该方法只需要改变LCOS上所加载的相位分布图即可形成不同的散焦图像,避免了传统方法中机械移动所造成的误差。模拟与实验结果均验证了所提方法的正确性和有效性。In traditional phase retrieval method based on transport of intensity equation （TIE）, there are problems of slow speed and low accuracy caused by moving the object to be measured or CCD in the process of light intensity images acquisition. In order to solve these problems, a new method using the liquid crystal on silicon （LCOS） as tunable-lens for phase retrieval is proposed in this paper. Firstly, the phase distribution images with different focal lengths are loaded in a LCOS to make it realize the function of tunable-lens. Then the light intensity images of different defocusing distances are collected in the same imaging plane by the designed system. Finally, the phase information is obtained by solving the TIE. With this method, different defocusing images can be formed by changing the phase distribution image loaded in the LCOS, avoiding the errors caused by mechanical shift. The correctness and effectiveness of the proposed phase retrieval method are verified by the simulation and experimental results.

关 键 词：测量 相位恢复 光强传输方程 硅基液晶 变焦透镜 

分 类 号：O436[机械工程—光学工程]