Two-Photon Scanning Structured Illumination Super-Resolution Volume Microscopy Utilizing a Synthetic Beam by Superposing a Nondiffracting Airy Beam and a Gaussian Beam

We propose a rapid volumetric image scanning structured illumination microscopy (SSIM) technique that utilizes the superposition of nondiffracting Airy and Gaussian beams, termed AG-SSIM, for super-resolution imaging. The key advantage of this approach lies in the complementary roles of the two beams, effectively combining their strengths to enhance the imaging performance. The nondiffracting property of the Airy beam allows the SSIM system to capture volumetric images within a single frame, facilitating the visualization of structures concealed behind strongly scattering media. Meanwhile, the focusing characteristics of the Gaussian beam at the center can enhance the effective excitation intensity, thereby increasing the contrast between the central lobe and the side lobes of the Airy beam, which, in turn, improves the fluorescence signal. This approach effectively eliminates the artifacts caused by the sidelobes of the Airy beam. In this study, the performance of the AG-SSIM system was evaluated using agarose gel embedded with fluorescent beads and a mitochondria cell dish. The results demonstrate that AG-SSIM captures more comprehensive axial information while offering superior lateral resolution compared with SSIM. In summary, the AG-SSIM technique offers a fast and effective approach for volumetric super-resolution imaging, leveraging the advantages of both Airy and Gaussian beams while eliminating imaging artifacts. Its capability to visualize structures in scattering media and rapidly monitor live cell dynamics makes it a promising tool for advanced biological imaging applications.