Fluorescence interference structured illumination microscopy for 3D morphology imaging with high axial resolution
Yile Sun, Hongfei Zhu, Lu Yin, Hanmeng Wu, Mingxuan Cai, Weiyun Sun, Yueshu Xu, Xinxun Yang, Jiaxiao Han, Wenjie Liu, Yubing Han, Xiang Hao, Renjie Zhou, Cuifang Kuang, Xu Liu
Abstract
Imaging three-dimensional, subcellular structures with high axial resolution has always been the core purpose of fluorescence microscopy. However, trade-offs exist between axial resolution and other important technical indicators, such as temporal resolution, optical power density, and imaging process complexity. We report a new imaging modality, fluorescence interference structured illumination microscopy (FI-SIM), which is based on three-dimensional structured illumination microscopy for wide-field lateral imaging and fluorescence interference for axial reconstruction. FI-SIM can acquire images quickly within the order of hundreds of milliseconds and exhibit even 30 nm axial resolution in half the wavelength depth range without z-axis scanning. Moreover, the relatively low laser power density relaxes the requirements for dyes and enables a wide range of applications for observing fixed and live subcellular structures.