Localized plasmonic structured illumination microscopy with gaps in spatial frequencies

Localized plasmonic structured illumination microscopy (LPSIM) is a super-resolution fluorescent microscopy method to image samples at a high speed with a wide field of view and low phototoxicity. Here we propose a methodology to extend the resolution capability of LPSIM by shifting spatial frequencies farther away from the diffraction-limited cutoff frequency with a plasmonic nano-array. We analyze the performance and accuracy of image reconstruction by using simulations of standard structured illumination microscopy (SIM) and blind-LPSIM. LPSIM experiments were also performed by using various LPSIM substrates and different microscope objectives. The experiments and simulations show that by shifting spatial frequencies farther away, resolution improvement can be extended up to 5 times beyond the diffraction limit with minimal deformation and artifacts in the reconstructed image.