Department of Electrical and Computer Engineering, University of California, San Diego, CA, 92093, USA.
Department of Pharmacology, University of California San Diego, San Diego, CA, 92093, USA.
Nat Commun. 2021 Mar 10;12(1):1559. doi: 10.1038/s41467-021-21835-8.
Structured illumination microscopy (SIM) is one of the most powerful and versatile optical super-resolution techniques. Compared with other super-resolution methods, SIM has shown its unique advantages in wide-field imaging with high temporal resolution and low photon damage. However, traditional SIM only has about 2 times spatial resolution improvement compared to the diffraction limit. In this work, we propose and experimentally demonstrate an easily-implemented, low-cost method to extend the resolution of SIM, named speckle metamaterial-assisted illumination nanoscopy (speckle-MAIN). A metamaterial structure is introduced to generate speckle-like sub-diffraction-limit illumination patterns in the near field with improved spatial frequency. Such patterns, similar to traditional SIM, are then used to excite objects on top of the surface. We demonstrate that speckle-MAIN can bring the resolution down to 40 nm and beyond. Speckle-MAIN represents a new route for super-resolution, which may lead to important applications in bio-imaging and surface characterization.
结构光照明显微镜（SIM）是最强大、用途最广泛的光学超分辨率技术之一。与其他超分辨率方法相比，SIM 在具有高时间分辨率和低光损伤的宽场成像方面显示出了独特的优势。然而，传统的 SIM 与衍射极限相比，仅能实现约 2 倍的空间分辨率提升。在这项工作中，我们提出并实验证明了一种易于实现、低成本的扩展 SIM 分辨率的方法，称为基于散斑超材料的照明纳米显微镜（speckle-MAIN）。引入超材料结构可在近场中产生具有改进空间频率的散斑状亚衍射极限照明图案。与传统的 SIM 类似，这些图案可用于激发表面上方的物体。我们证明 speckle-MAIN 可以将分辨率降低到 40nm 以下。speckle-MAIN 代表了一种新的超分辨率途径，可能会在生物成像和表面特征化等领域带来重要应用。
