Phase-only mask for superoscillatory enhanced resolution in confocal microscopy

Abstract

In this work, we present a simple phase mask that generates a superoscillatory spot suitable for confocal scanning microscopy enabling lateral sub-diffraction resolution. When considering linearly polarized light, the mask enhances the resolving power along the axis perpendicular to the polarization direction. The symmetry of the enhancement is recovered if the mask is combined with radial polarization.