Transverse superresolution and axial extended focal depth realized by the tunable phase pupil filter

Abstract

In order to overcome the drawback of the conventional pupil filters and realize the tunable superresolution of the optical system, a new type of tunable pure phase filter composed of a half-wave plate located between two quarter-wave plates is presented in this paper, in which the half-wave plate is made of two zones. The simulation results show that with such a pupil filter the tunable transverse superresolution as well as the axial extended focal depth of the optical system can be realized by rotating any zone of the half-wave plate.