Effect of processing strategies on the stochastic transfer function in structured illumination microscopy

The stochastic transfer function (STF) has been introduced in previous publications [J. Opt. Soc. Am. A 26, 1622 (2009)]. This encompasses the conventional transfer function as well as a measure of the noise at each spatial frequency. We use the STF as a metric to characterize the noise performance of structured illumination microscopy where the final image is synthesized from several constituent images. In particular, we examine the effect of different processing strategies on the signal to noise at different spatial frequencies. We extend the so-called weighted average approach to account for different grating periods, where the noise in different image contributions is correlated. Finally, we demonstrate by simulation that a superior STF does lead to better imaging of a two-point object.