Super-resolution with a complex-amplitude pupil mask encoded in the first diffraction order of a phase grating

Abstract

Diffraction imposes a barrier to resolve objects smaller than half the wavelength used to illuminate them. In optical microscopy, this barrier was surpassed 25 years ago. One form of achieving super-resolution is the use of complex-amplitude pupil masks. Spatial light modulators can be used to produce these masks, if we compensate the aberrations introduced by them. In this paper we propose a method to encode a complex-amplitude pupil mask in a phase-only spatial light modulator of the Liquid Crystal on Silicon (LCoS) variety. We describe the form in which the pupil mask is encoded in a phase grating generated with an LCoS spatial light modulator, and how the aberrations introduced by this device can also be compensated with this grating. We present numerical and experimental results that validate the method.