Polarization encoding for optical security systems

Abstract

A polarization-encoding system for optical security verification is proposed. The polarization information is bonded to an identification card for security verification. As the polarization state cannot be imaged by an ordinary intensity-sensitive device such as a CCD camera, it can provide an additional degree of freedom in using optics to secure information. The expressions for polarization encoded input images are developed using Jones polarization calculus. A nonlinear joint transform correlator is used to provide an optical validation system. Computer simulations and optical experimental results are shown in support of the proposed method.