透过散射介质的具有深度分辨能力和宽视场角的高品质光学成像技术研究

A further development and the application of the area of imaging through scattering medium need to solve the obstacle of imaging quality. Among them, the scattering imaging technique, which is based on correlated scattering light, is limited to the "Optical Memory Effect" of the scattering medium. How to acquire high quality imaging and solve the problems of depth resolved ability, large Field-Of-View, adapted to thick scattering medium are still needed to be researched. To achieve this goal, the applicants have good experience in the related area: an adaptive wavefront shaping technique have been built to imaging through a scattering medium and focusing through a scattering medium; an improvement have been made to speed up the wavefront shaping process; a real-time wide angle full color imaging technique have been developed to imaging through a scattering medium. The applicants’ preliminary experiment found that the scattering light still gets high correlation even beyond the range of axial memory effect, which indicates the potential of depth resolved imaging through a scattering medium. So based on this, the physics of scattering will be studied and research on exploiting the correlation of the scattering light which is helpful to imaging recovery. This proposal intends to enhance the quality of imaging by well-designed optical system, optimal imaging program to acquire longitudinal information deep into the scattering medium and realize a large Field-Of-View. It is a comprehensive experimental research project including fundamental optics theory problems and technical challenges. The research results of the project will bring important applications and push a further development of the scattering light imaging technique.

透过散射介质的成像技术在进一步的研究和推广应用中需要突破成像效果的制约。其中，受限于散射体的记忆效应，基于相关散射光实现的散射成像技术在解决深度分辨能力、成像可视角的扩大和厚散射介质的适用性等问题上还有待深入研究。申请人在这一领域上已经积累了大量的研究经验：建立了自适应光场调控技术实现了散射成像及散射光能量的重新汇聚；提出了实现彩色物体实时大角度的散射成像技术。预实验结果发现了散射光在散射透镜的景深范围以外仍具有很强的相关性，表明了散射体纵向记忆效应可以突破并利用于纵向分辨能力的提高。本项目将在此基础上继续讨论光的散射过程，研究提高散射光的相关性的新机理，改进成像过程和设计优化的光学系统充分利用相关散射光，突破散射体记忆效应的限制，实现物体深度信息的获取和成像可视角的扩大，获得高品质的图像。本项目是集光学基础理论问题和工程技术挑战于一体的实验研究，有望推动该领域的发展和应用。

透过散射介质的光学成像技术在近年来获得了迅速发展并取得了许多重要进展。本项目主要关注的是利用散斑相关方法实现的散射成像。该方法一直以来受限于散射体的记忆效应，在解决深度分辨能力、成像质量以及成像场景的局限性等方面尚有许多问题有待研究和突破。在本项目的支持下，项目组成员对光的散射过程进行了深入的研究，通过成像过程的改进和光学系统的优化提高了散射光的相关性，发现了散斑在传播过程中在纵向的缩放效应，并利用这一效应实现透过散射介质物体深度信息的获取，获得了三维物体透过散射介质的成像，在成像深度上突破了传统的记忆效应的限制，获得了对比以往5倍以上的成像景深的扩展。此外本项目还对成像过程中所使用的物理模型和算法进行了深入的研究，发现了维纳滤波解卷积在散射成像应用上影响信噪比的关键参数并利用记忆效应对解卷积模型进行了改进，极大的提高了散射成像的质量。本项目还利用了动态散射介质的统计特性，深入研究了以往的频谱域的“浴帘效应”并对其做出了改进，实现了在共线的光学结构下对反射式的非荧光非自发光物体透过薄散射介质的成像恢复。本项目是集光学基础理论问题和工程技术挑战于一体的实验研究，项目的研究成果进一步推动了散射成像领域的发展，对散射过程中更多的物理规律获得了更进一步的了解并予以应用于成像方面。项目所取得的成果有望推动散射成像技术在生物显微、安全监控、工业生产和军事国防等领域的进一步发展。