A phase-based optical encryption system with polarisation encoding

In this paper we present an optical encryption system based entirely on the encryption of information using the phase component of a wavefront. The novelty of our approach lies in the utilisation of polarisation for the visualisation of the decoded information. We show results for an experimental system in which two parallel aligned liquid spatial light modulators are used to produce and subsequently decrypt binary optical phase information. We demonstrate that the direct pixel mapping approach that we use provides a robust and simple to implement architecture for optical encryption. (C) 2000 Published by Elsevier Science B.V. All rights reserved.