基于数字微镜器件超像素法实现散射介质传输矩阵的自参考干涉测量  

Self-reference interferometric measurement of scattering medium transmission matrix based on digital micromirror device superpixel method

作　　者：廖涌泉 张晓雪 刘卉 朱香渝 陈旭东 林志立 Liao Yong-Quan;Zhang Xiao-Xue;Liu Hui;Zhu Xiang-Yu;Chen Xu-Dong;Lin Zhi-Li(Fujian Provincial Key Laboratory of Light Propagation and Transformation,College of Information Science and Engineering,Huaqiao University,Xiamen 361021,China)

机构地区：[1]华侨大学信息科学与工程学院,福建省光传输与变换重点实验室,厦门361021

出　　处：《物理学报》2023年第22期136-145,共10页Acta Physica Sinica

基　　金：国家自然科学基金青年科学基金(批准号:61605049);厦门市青年创新基金项目(批准号:3502Z20206013);中央高校基本科研业务费专项资金(批准号:ZQN-707)资助的课题。

摘　　要：散射介质的传输矩阵系统描述了散射介质对输入与输出光场之间的变换关系,是研究与控制光在无序介质中传输特性的重要工具.本文使用数字微镜器件实现散射介质传输矩阵的自参考干涉测量,首先利用超像素法实现对入射光的复振幅调制获得同时包含参考光和信号光的复合场,进而基于四步相移法分别测量了散射介质在Hadamard基和轨道角动量(OAM)基下的传输矩阵.进一步,根据相位共轭原理实现了光透过散射介质后的单点聚焦、多点聚焦以及涡旋聚焦,验证了传输矩阵测量的准确性.该方法能够有效提高光场调制的自由度,实现散射介质传输矩阵的测量,对散射环境下的光学成像和光通信等具有潜在应用价值.When light propagates through complex medium,such as biological tissue and multimode fiber,refractive index inhomogeneity causes multiple scattering and distortion.This phenomenon is usually seen as obstacles for biomedical imaging,telecommunications,photodynamic therapy and so on.Thus,manipulation of the incident wavefront to compensate for the wavefront distortion due to multiple scattering has been an interdisciplinary subject of interest.Fortunately,wavefront shaping technologies have emerged to provide versatile solutions to minimize the influence of light scattering.By modulating the incident light into a special wavefront with a spatial light modulator,focusing through scattering medium is obtained.To date,several wavefront shaping techniques have been proposed,mainly including transmission matrix inversion,feedback based iterative optimization,and digital optical phase conjugation.Unlike a planar wavefront,the modulated light with special wavefront is transformed into a bright optical focus spot or a desired focus pattern after the scattering medium.Among the proposed approaches,the transmission matrix is considered as a significant tool to characterize a multiple scattering medium with the purpose of manipulating light propagation through it,which contains all the information related to the input field and the scattered output field.In this work,we experimentally measure the transmission matrix of scattering media based on self-reference interference method with a digital micromirror device.Unlike the conventional setup,which divides the incident wavefront into a signal part and reference part,in the self-reference interference method,the reference light is superimposed directly on the signal light to form a new set of input light fields.This self-reference interference method effectively improves the degree of freedom of optical field modulation.Moreover,the intensity ratio between the signal light and the reference light can be adjusted conveniently.In our experiment,this superimposed field is generate

关 键 词：自参考干涉 传输矩阵 数字微镜器件 散射介质 

分 类 号：O436.2[机械工程—光学工程]