基于超振荡光学现象的宽带消色差远场超分辨成像原理和方法研究

The far-field optical super-resolution methods have aroused considerable interests for its great real-world applications. Some super-resolution methods, such as stimulated emission depletion microscopy (STED) and structured illumination microscope (SIM), have demonstrated their sub-diffraction abilities, but work only for limited classes of specimens or special illumination. The super-oscillatory light field with the localized ultra-fast oscillatory spectrum, could be used for the far-field super-resolution imaging. However, they still have constrains in applications due to the narrow working band and low focusing energy. The project proposed a method to design a broadband, achromatic, planar super-oscillatory lens with the metasurface, which was convenient design and possesses sub-wavelength modulation ability of phase or magnitude. The lens will be used in a non-scanning telescopy imaging system to realize real-time broadband super-resolution imaging in the far field. In this project, the mechanism of the broadband super-oscillatory behavior and the designing method of broadband super-oscillatory devices will be studied. The mathematic model for super-oscillatory imaging will be established. The field of view of super-oscillatory imaging will be extended. The design, fabrication and characterization of the broadband super-oscillation structures will be investigated. The super-resolution imaging system will also be designed and constructed. The object of this project is to provide a novel route to achieve a convenient designed, ultra-thin and broadband super-oscillatory lens and a real-time, far-field super-resolution imaging method, which has great potential applications in areas, including spatial imaging, microscope and so on.

物、像面均在远场的超分辨成像方法是当前光学成像领域的研究热点，具有广泛的应用前景。受激辐射损耗、结构光照明显微等超分辨技术面临样品荧光染色、特殊照明等问题，限制了其应用范围。研究表明利用超振荡光场局部频谱超快振荡的特性可实现远场超分辨成像，但存在带宽窄、能量低等问题。针对以上问题，本项目提出利用超构表面设计灵活、亚波长尺度位相/振幅调制等特点，构建宽带消色差平面超振荡光场调制器件；并将其用于非扫描式的望远成像系统，实现宽带实时远场超分辨成像。本项目进一步研究宽带超振荡行为和器件设计方法；建立超分辨成像数理模型；拓展成像视场；完成宽带超振荡器件设计、加工及成像系统搭建和验证。本研究有望提供一种设计方便、超轻薄的宽带消色差超振荡器件，以及实时的宽带远场超分辨成像方法，解决传统超分辨成像近场限制、样品受限、特殊照明等应用局限性，在空间成像、显微等领域具有重要应用前景。

物、像面均在远场的超分辨成像方法是当前光学成像领域的研究热点，具有广泛的应用前景。而受激辐射损耗、结构光照明显微等远场超分辨技术面临样品荧光染色、特殊照明等问题，限制了其应用范围。研究表明利用超振荡光场局部频谱超快振荡的特性可实现远场超分辨成像，但存在带宽窄、具有色差等问题。本项目针对以上问题，从基于超振荡光场的超衍射成像理论机理和超构表面电磁调控机理，基于超构表面的消色差超振荡成像器件设计、优化和加工制备，以及消色差超振荡光场成像器件和系统测试和表征三个方面开展研究，并取得了系列研究成果。揭示了基于超振荡光场的远场超分辨成像机理；分析了各种超构表面结构的相位、振幅、偏振调控特性，并建立超构表面微纳结构与超振荡光场之间的对应关系；掌握不同超构表面结构对超振荡器件带宽、偏振与色散调控方法，并采用上述方法完成了基于超构表面超振荡器件的正、逆向设计与优化，研制了包括多波长消色差超振荡成像、宽带连续消色差超振荡成像、偏振切换成像等在内的平面消色差光学成像器件；分析了远场超分辨成像分辨力、视场、像差等特性规律和影响因素，掌握基于超振荡现象的超分辨望远成像系统设计方法，基于超构表面电磁调控原理，搭建了基于开普勒式光路的宽带消色差超分辨成像和基于切趾滤波的宽带超振荡望远成像系统，并完成了系统性能的实验验证，获得400nm-700nm消色差带宽、0.625倍衍射极限成像分辨力的系统成像结果，为远场超振荡成像原理方法在超分辨望远、显微、及存储领域的应用提供基础。相关成果共发表SCI收录研究论文9篇，中文核心期刊论文1篇，正在投稿论文2篇，受理或者授权具有自主知识产权的发明专利7项。