Resolution-enhanced SOFI via structured illumination

By analyzing the statistics of the temporal fluctuations from the blinking emitters, super-resolution fluctuation imaging (SOFI) achieves super-resolution while imposing fewer constraints on the blinking behavior of the probes and is more suitable for low signal-to-noise ratio acquisition than localization methods. However, determined by the square root of cumulation orders, the resolution improvement of SOFI highly restricts its promotion into high-resolution observations. In this Letter, abandoning the default flat illumination in stochastic imaging methods, we introduce structured illumination (SI) (e.g., Gaussian or sinusoidal pattern) into SOFI (SI-SOFI) to render greatly enhanced resolution. Through simulation with parameters of both real acquisition procedures and microscope properties, we examine the feasibility of SI-SOFI and obtain a resolution improvement of four-six folds at just second-order cumulation compared to wide-field imaging. In addition, a practical pathway for the SI-SOFI reconstruction is offered.