突破衍射极限的远场光学成像方法

随着人们对微观世界探索的不断深入,在纳米科技和生命科学等领域要求成像系统的分辨率达到微纳尺度.远场成像技术具有工作距离远、无损伤等优点,但由于衍射极限的存在,限制了其往更高分辨率方向的发展,因而突破衍射极限的远场成像技术成为了研究的热点.介绍了突破衍射极限的基本原理,综述了近年来通过非线性效应、特殊光照明、耦合元件和微球收集倏逝波突破衍射极限的远场光学成像方法,阐述了其在生物成像领域的应用,最后给出了突破衍射极限的远场成像的发展趋势.

Breaking Through the Diffraction Limit Using Far-field Optical Imaging Methods

With the exploring of microscopic world, nano-technology and life science have been investigated under micron and nano scales. Compared with near-filed imaging methods, far-field microscopic technique has many advantages, such as long working distance and non-damage. However, the resolution of far-field imaging is restrained by the diffraction limit. How to overcome this limit has become the focus of many research areas. In this paper, the principle of breaking through the diffraction limit is introduced. The latest far-field methods based on the nonlinear effect, special light illumination, coupling elements and microsphere are briefly reviewed including their biomedical applications. Finally, the trend of the methods, which overcomes the diffraction limit in far field, is given.