Frequency comb ptychoscopy.

Multiheterodyne techniques using frequency combs-radiation sources whose lines are perfectly evenly-spaced-have revolutionized science. By beating sources with the many lines of a comb, their spectra are recovered. Even so, these approaches are fundamentally limited to probing coherent sources, such as lasers.

Generalized stepwise optical saturation enables super-resolution fluorescence lifetime imaging microscopy.

We present a novel super-resolution fluorescence lifetime microscopy technique called generalized stepwise optical saturation (GSOS) that generalizes and extends the concept of the recently demonstrated stepwise optical saturation (SOS) super-resolution microscopy [Biomed. Opt. Express9, 1613 (2018)].

Saturation-compensated measurements for fluorescence lifetime imaging microscopy.

Fluorophore saturation is the key factor limiting the speed and excitation range of fluorescence lifetime imaging microscopy (FLIM). For example, fluorophore saturation causes incorrect lifetime measurements when using conventional frequency-domain FLIM at high excitation powers. In this Letter, we present an analytical theoretical description of this error and present a method for compensating for this error in order to extract correct lifetime measurements in the limit of fluorophore saturation.