DMD光学相位共轭系统的关键参数敏感性研究  

Key parameter sensitivity research of DMD based optical phase conjugation system

作　　者：宋超 汪待发[1,2] SONG Chao;WANG Daifa(, School of Biological Science and Medical Engineering, Seihang University, Seijing 100083, China;Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing 100083, China)

机构地区：[1]北京航空航天大学生物与医学工程学院,北京100083 [2]北京航空航天大学,生物医学工程高精尖创新中心,北京100083

出　　处：《激光杂志》2018年第6期1-5,共5页Laser Journal

基　　金：国家自然科学基金项目(No.61675013.No.61761166007)

摘　　要：数字光学相位共轭（Digital optical phase conjugation,DOPC）技术可穿透或在散射介质深部形成高能量、高对比光学聚焦,为组织深层的光激发（如光遗传学）、光成像、光治疗等提供革新的技术手段。基于数字微镜装置（Digital micromirror device,DMD）的DOPC具有响应速度快的独特优势,有望将该技术推向活体应用。针对基于DMD的DOPC散射光学聚焦系统,研究了与DMD共轭的平面镜的位置偏差这一重要却难以准确确定的参数对系统性能（峰背比PBR）的影响,并在课题组之前所提出设计的基础上,提出了一种新的基于DMD反射特性的波前记录光路方案。结果表明,两种设计对于平面镜位置偏差有较好的容忍度,在1mm的范围内,PBR均可保持在最大值的80%以上。新设计对于位置偏差的容忍度更高,达到3mm左右,但其能达到的最高PBR效率要略低近4个百分点。相关设计及结果可为基于DMD的DOPC光学聚焦系统的设计、日常调试等提供新方法及理论指导。Digital optical phase conjugation （ DOPC ） has the potential of focusing through or deep inside highly scattering medium, providing an innovative method for deep tissue applications, such as optical excitation, imaging, and therapy. Digital micromirror device （DMD） based DOPC has the advantage of fast response speed, which is essential for in-vivo applications. For DMD based DOPC system, this article analyzed its performance sensitivity to one important parameter, the position deviation of the mirror conjugated to DMD. In addition, based on our previous optical design, a new wavefront recording design is proposed by using the reflection property of DMD. Results demonstrated that, the two designs has acceptable robustness to the position deviation of the mirror, where the peak to background ratio （PBR） can keep above 80% of the maximum value for deviation within lmm. The new design has better robustness, the position deviation value can be up to 3mm, but the achievable optimal PBR efficiency is around 4% lower than the previous design. The optical design and results can provide new methods and theoretical guidance for the development and routine adjustment of DMD based DOPC.

关 键 词：光学聚焦 散射介质 光学相位共轭 数字微镜装置 峰背比 

分 类 号：O438.1[机械工程—光学工程]