Studying the illumination puzzle towards an isotropic increase of optical resolution

The aim of this work is to propose and analyze optical schemes to obtain an improvement of resolution in optical fluorescence microscopy. This goal can be achieved by implementing interfering illumination beams. We start from the insertion, on the illumination arm of the confocal microscope, of appropriately phase plates inducing laterally interfering beams, and then we propose to exploit two-photon excitation, too. We plan to implement solutions for shaping also the axial component of the point spread function by use of phase-only pupil filters and binary filters. In order to implement such schemes we use a computational simulation mainly based on a vectorial approach coupled to experimental procedures utilizing ultra-thin fluorescent layers and thick gels containing immobile fluorescent molecules as 2D and 3D phantoms, respectively. As well, image processing and successive views can be recombined to get a final isotropic improvement of resolution.