Resulting from the attenuation of evanescent waves in imaging, conventional microscopy techniques always yield few subwavelength features. In this Letter, a nonlinear far-field super-resolution technique is investigated, which is theoretically beyond the linear diffraction limitation. Based on the orientationally enhanced photorefractive effect of polymer, an inherently phase-matched diffraction grating is established and generates daughter modes by wave mixture. Almost all of these modes can pass through a finite-aperture filter and be sensed for reconstruction. An improvement of resolution of about four times is obtained and expected to be increased further. This work may provide a potential strategy for various subwavelength-resolved imaging applications.

中文翻译：

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通过定向增强聚合物中的光折变效应进行的非线性超分辨率成像

由于imaging逝波在成像中的衰减，传统的显微技术总是产生很少的亚波长特征。在这封信中，研究了一种非线性远场超分辨率技术，该技术在理论上超出了线性衍射极限。基于聚合物定向增强的光折变效应，建立了固有的相位匹配衍射光栅，并通过混波产生子模。几乎所有这些模式都可以通过有限孔径滤波器，并被感知以进行重构。分辨率提高了大约四倍，并且有望进一步提高。这项工作可能为各种亚波长分辨成像应用提供潜在的策略。