Digital-micromirror-device-based illumination strategies for background suppression in single-molecule localization...

Single-molecule localization microscopy (SMLM) achieves super-resolution imaging by exciting sparsely distributed fluorescent emitters and precisely localizing their positions over long acquisition sequences. However, background signals arising from out-of-focus structures and autofluorescence can severely reduce the signal-to-noise ratio, thus compromising the localization precision. In this work, we introduce two controllable illumination strategies based on a digital micromirror device (DMD). By selectively modulating the illumination region in both space and time, these approaches effectively enhance the photon-to-background ratio and improve the localization precision. Experimental results demonstrate that the proposed method significantly boosts the imaging performance without increasing computational or instrumental complexity, providing new opportunities for SMLM imaging in challenging specimens such as highly scattering tissues.