基于传输矩阵的公里级多模光纤计算成像技术(特邀)  

Computational imaging over a kilometer-scale multimode fiber based on transmission matrix(invited)

作　　者：马梓豪 刘淏天 叶建伟 徐毅 秦玉文 MA Zihao;LIU Haotian;YE Jianwei;XU Yi;QIN Yuwen(Institute of Advanced Photonics Technology,School of Information Engineering,Guangdong University of Technology,Guangzhou 510006,China;Key Laboratory of Photonic Technology for Integrated Sensing and Communication,Ministry of Education of China,Guangdong University of Technology,Guangzhou 510006,China;Guangdong Provincial Key Laboratory of Information Photonics Technology,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]广东工业大学信息工程学院先进光子技术研究院,广东广州510006 [2]广东工业大学通感融合光子技术教育部重点实验室,广东广州510006 [3]广东工业大学广东省信息光子技术重点实验室,广东广州510006

出　　处：《红外与激光工程》2024年第9期235-242,共8页Infrared and Laser Engineering

基　　金：国家自然科学基金优秀青年基金项目(62222505);国家自然科学基金项目(62335005);广东省“珠江人才计划”引进创新创业团队项目(2019ZT08X340)。

摘　　要：多模光纤因其高通量的优点,成为短距光纤通信的重要传输介质之一。然而,不同模式在多模光纤的传输过程中会发生模式色散,导致输出端形成杂乱无序的散斑,无法直接通过简单的强度探测解调出输入信息。为解决这一问题,该研究探讨了基于传输矩阵方法在公里级多模光纤上实现信息并行传输,结合精准传输矩阵测量及求逆,不仅成功实现了256阶灰度图像信息的高保真计算成像,而且实现了基于传输矩阵的公里级多模光纤视频传输,验证了该方法的准确性和有效性。实验结果表明:借助空间光波前调制手段,结合传输矩阵求逆方法,随机二维码和高清全彩视频传输的准确性均达到了100%,解调准确率优于传统的散斑相关散射矩阵方法。该研究的成果可为短距光纤通信、空间光通信和光学安全保密通信等领域的发展提供新的思路。Objective Multimode fiber(MMF)has become one of the important media for short-reach fiber communication because of its high throughput property.However,modal dispersion of the MMF results in the formation of seemly chaotic speckle at the distal end of the MMF,where the input information cannot be directly decoded using simple intensity detection.Information decoding from the speckle output of the MMF requires accurate characterization of the MMF's multiple-input-multiple-output(MIMO)transmission properties.Currently,popular computational imaging methods for retrieving the mapping functions of MIMO systems include the transmission matrix(TM)-based methods and the deep learning-based methods,both of which have their advantages and disadvantages.To solve the problem of precise decoding over an MMF,this study explores the parallel information transmission over a kilometer-scale MMF based on the inverse transmission matrix(ITM)method.The results of this study could provide new insight for the development of short-reach fiber communication,spatial optical communication and secure optical communication.Methods This article utilizes wavefront shaping to accurately measure the TM of the MMF,where self-interference optical setup is used to measure the complex optical field at the distal end of the MMF.Binary information and 256-level grayscale image with a resolution of 32×32 are used as the phase encoded information of the input wavefront,which are modulated by a digital micromirror device and coupled into the MMF.Then the ITM method is used to retrieve the encoded information from the chaotic speckle patterns.If the TM is not a square matrix,pseudo-inversion of the matrix is performed instead.Results and Discussions The experimental results are shown(Fig.3(a)).It can be seen that the ITM method can retrieve the phase encoded information over the MMF,providing the TM of the MMF and the complex light field at the output can be precisely measured.The comparisons with the experimental results using the scattering-correlatio

关 键 词：多模光纤 传输矩阵 波前整形 计算成像 

分 类 号：O438[机械工程—光学工程]