Three-dimensional shifting selectivity of decryption phase mask in a double random phase encoding holographic memory

We have theoretically analyzed and experimentally investigated the three-dimensional shifting selectivity of the decryption phase mask in a double random phase encoding holographic memory. The lateral shifting selectivity of the decryption phase mask in the system depends on not only its correlation length but also the dimension of recording medium and the distance between phase mask and the hologram. The longitudinal diffraction selectivity is inverse proportional to the dimension of recording medium and proportional to the distance between hologram and the phase mask. The diffraction selectivity derived in this paper offers important information for alignment and reposition of the decryption phase key in practical optical implementations.