基于数字微镜器件并行共焦成像的光点阵列优化  

Spot Array Optimization of Parallel Confocal Imaging Based on Digital Micromirror Device

作　　者：朱茜 杨西斌[2,3] 李思黾[2] 李辉[2] 王驰[1] 刘首鹏 简俊明[2] 熊大曦 Zhu Qian;Yang Xibin;Li Simin;Li Hui;Wang Chi;Liu Shoupeng;Jian Junming;Xiong Daxi(School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200072, China;Jiangsu Key Laboratory of Medical Optics, Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of Sciences, Suzhou, Jiangsu 215163, China;Center of Optics Health, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163, China)

机构地区：[1]上海大学机电工程与自动化学院,上海200072 [2]中国科学院苏州生物医学工程技术研究所江苏省医用光学重点实验室,江苏苏州215163 [3]中国科学院苏州生物医学工程技术研究所光健康研究中心,江苏苏州215163

出　　处：《光学学报》2018年第1期252-260,共9页Acta Optica Sinica

基　　金：国家自然科学基金青年基金(61405238;61475185;51376191);江苏省自然科学基金青年项目(BK20141206);苏州市医疗器械与新医药专项(ZXY201433)

摘　　要：数字微镜器件(DMD)的灵活性有助于实现并行共焦成像。设计并搭建了基于DMD的并行共焦成像系统,分析了DMD光点阵列对轴向分辨率、横向分辨率和图像对比度的影响,得出了最优光点阵列参数。结果表明:光点越小,则横向和轴向分辨率越高;当光点间距大于光点大小时,增大光点间距对成像的横向分辨率无明显改善;对于1×1微镜,光点间距为光点大小的4倍时对应的图像对比度最高,即1×1光点大小、4倍光点间距为最优光点阵列。对数值孔径为0.25的物镜而言,最优光点阵列对应的横向分辨率优于512lp/mm,轴向分辨率可达7.82μm,均达到衍射极限。基于最优光点阵列的三维体光栅成像比宽场成像具有更高的分辨率和明显的层切效果,与激光扫描共焦成像相比无较大差距。基于DMD的并行共焦成像系统在保证高速成像的前提下,实现了高分辨率和高图像对比度的光学层切成像,在实时成像和三维成像中有一定的优势和应用前景。The flexibility of a digital micromirror device（DMD）helps to realize parallel confocal imaging.A parallel confocal imaging system based on DMD is designed and built.The influences of DMD spot array on axial resolution,lateral resolution and image contrast are analyzed to obtain the best spot array parameters.Results show that,the smaller the spot size is,the higher the lateral and axial resolution are.When the spot distance is larger than the spot size,the imaging horizontal resolution is not improved obviously with the increasing distance between spots.The imaging contrast is the highest when the spot interval equals to four times of spot size for 1×1 micromirror.That is to say,the optimal spot array is that spot size equals to 1×1 and spot interval equals to four times of spot size.For an objective lens with a numerical aperture of 0.25,the lateral resolution of optimal spot array is superior to512 lp/mm,and its axial resolution can reach 7.82μm,which reaches diffraction limit.When the optimal spot array is used to image three-dimensional body grating,it has higher resolution and obvious optical sectioning effect than that of wide field imaging,and has no much difference compared with that of laser scanning confocal imaging.The parallel confocal imaging system based on DMD achieves optical sectioning imaging with high resolution and high imaging contrast on the premise of high speed imaging.It has certain advantages and application prospects in realtime imaging and three-dimensional imaging.

关 键 词：显微 应用光学 并行共焦成像 数字微镜器件 轴向分辨率 横向分辨率 图像对比度 

分 类 号：O439[机械工程—光学工程]