Compact LCOS–SLM Based Polarization Pattern Beam Generator

In this paper, a compact optical system for generating arbitrary spatial light polarization patterns is demonstrated. The system uses a single high-resolution liquid crystal (LC) on silicon (LCOS) spatial light modulator. A specialized optical mount is designed and fabricated using a 3D printer, in order to build a compact dual optical architecture, where two different phase patterns are encoded on two adjacent halves of the LCOS screen, with a polarization transformation in between. The final polarization state is controlled via two rotations of the Poincaré sphere. In addition, a relative phase term is added, which is calculated based on spherical trigonometry on the Poincaré sphere. Experimental results are presented that show the effectiveness of the system to produce polarization patterns.

I. Introduction

The production of two-dimensional polarization patterns has become a relevant issue for a number of different applications. In particular, cylindrical vector beams [1], of which radially and azimuthally polarized beams are a subclass, are especially interesting due to their very appealing properties upon focalization with high aperture lenses [2], or because their relation with the orbital angular momentum of light [3]. Additionally, they are eigen-solutions of cylindrical resonators and optical fibers [4].