基于一体化微球物镜的超分辨成像系统  

Super-resolution imaging system based on integrated microsphere objective lens

作　　者：宋扬[1,2] 杨西斌 闫冰[2] 王驰 孙建美 熊大曦 Song Yang;Yang Xi-Bin;Yan Bing;Wang Chi;Sun Jian-Mei;Xiong Da-Xi(School of Mechatronic Engineering and Automation,Shanghai University,Shanghai 200444,China;Research Center of Light for Health,Suzhou Institute of Biomedical Engineering and Technology,Chinese Academy of Sciences,Suzhou 215163,China)

机构地区：[1]上海大学机电工程与自动化学院,上海200444 [2]中国科学院苏州生物医学工程技术研究所,光与健康研究中心,苏州215163

出　　处：《物理学报》2020年第13期84-92,共9页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2017YFC0109900,2018YFC0114800);国家自然科学基金(批准号:61405238);江苏省重点研发计划(批准号:BE2018666)资助的课题.

摘　　要：利用直径微米量级的透明微球与传统光学显微镜相结合,可以在白光下实现超分辨成像.目前大部分研究是将微球直接播撒到样品表面,由于微球位置的随机性和不连续性导致无法实现特定区域的完整成像,极大限制了该技术的使用范围.使用微探针或微悬臂黏附微球,通过三维位移台精确控制微球位置,一定程度上解决了上述问题,但是需要对微球位置进行精准操控.本文提出了一种结构稳定、参数可控、简单易用的基于一体化微球物镜的超分辨成像系统,对微球与物镜进行了一体化安装设计,通过设计侧视成像及位置反馈系统实现了对微球、物镜和样品三者之间距离的精准控制,结合通用的显微成像系统,实现了对可控特定区域的超分辨成像.该系统将普通显微物镜(40×,NA 0.6)的分辨能力提高了4.78倍,最高可以看到100 nm的样品特征.该一体化物镜可以搭配普通光学显微系统使用,实现超分辨成像,提高了微球超分辨技术的通用性,在亚衍射极限样品的超分辨成像方面具有广泛的应用价值.White-light super-resolution imaging,proposed in 2011,has been achieved by combining the transparent microspheres of the micron scale with an ordinary optical microscope.At present,in most of the researches employed is the way of spreading microspheres directly onto the surface of sample,which causes the randomness and discontinuity of microspheres.It is impossible to achieve the complete imaging of specific regions,which greatly limits the application scope of this technology.Such an issue can be solved by using microprobes or micro-cantilevers to precisely transfer the location of microsphere,but for doing so,a sophisticated controlling system is required,which is costly and not user-friendly.In this paper,a robust,controllable,easy-to-use integrated design which can efficiently consolidate microsphere and objective together is demonstrated for super-resolution imaging.The PDMS and customized metal sleeve are used to encapsulate the microsphere semi-submerged on the ordinary objective lens to achieve an integrated design.In this system,the distances among the microsphere,objective lens and the sample are controlled accurately by building a side-view imaging and position feedback system.With the help of a universal microscopic imaging system,the super-resolution imaging of specific controlled areas is realized.Based on theoretical analysis,the semi-submerged structure of the 100-μm-diameter BaTiO3 microsphere has a strong focusing effect,which can form the so-called‘photonic nanojet’on a micro-scale in length and on a sub-diffraction scale in waist to possess the ability to break through the diffraction limit within the range of focal length.At the same time,experiments are carried out for investigating imaging performances at various working distances in the air.According to the experimental results,the system can clearly distinguish between the CPU lattice features of 200 nm and the Blu-ray disc fringe of 100 nm,which means that the resolution of the ordinary microscopic objective lens(40×,NA 0.6)is sign

关 键 词：微球超分辨成像 一体化物镜 侧视成像反馈系统 

分 类 号：TH742[机械工程—光学工程]