Ring Array Illumination Microscopy: Combination of Super-Resolution with Large Field of View Imaging and long Working Distances

Here we present a novel fluorescence microscopy concept which enables a direct integration of Super-Resolution Microscopy (SRM) approaches (SIM/Nanosizing, STED, SMLM, MINFLUX, SIMFLUX) into microscopy systems with working distances (WD) up to the multicentimeter range while still allowing nanometer scale resolution at selected sites. This becomes possible by a "synthetic aperture" illumination mode with multiple, constructively interfering excitation beams positioned in a "Ring-Array" arrangement around a beam free interior zone containing instrumentation involved in complementary imaging modes. The feasibility of such a direct correlative microscopy method is validated by extensive numerical simulations; on the basis of these calculations, experimental implementation options are discussed. Such "Ring Array" illumination modes may be useful for various correlative microscopy methods, such as a direct combination of correlative light and electron microscopy in the same device (dCLEM); or a direct combination of low NA/large field-of-view widefield microscopy and super-resolution of selected sites in the same device (direct Correlative Opical Microscopy/dCOLM). Ring-Array supported correlative microscopy modes will open novel imaging perspectives in a variety of disciplines, from material sciences to biomedical applications.