Holographic 2D Mixed Polarization Deflection Elements

Abstract

Abstract Two-dimensional optical implementations of permutation elements are currently of interest as components in switching network systems. These elements can reorder and change the spacing of a set of input channels at an output plane. Here an implementation of such an element that uses holographic gratings is presented and theoretically analysed. Each individual grating is recorded in a rotated position with respect to the others. In this way arbitrary 2D interconnections are achieved at the cost of growing design complexity. The complexity of the exposure procedure results from the wish for high diffraction efficiency at reconstruction with light of mixed polarization. The inclusion of the Fresnel reflection coefficients adds further to the difficulty of the analysis. Experimental and theoretical results are compared and found to be broadly in agreement. This information is then used to implement two practical components.