Angular-Multiplexing Optical Multiple-Image Encryption Based on Digital Holography and Random Amplitude Mask

Abstract

We propose an improved optical image encryption scheme. By illuminating original images positioned in the input plane of the 4-f correlator and introducing reference waves with different incident angles in the output plane, we accomplish multiple-image encryption. To enhance the feasibility of the system and decrease the coding compliance for random phase mask, we apply the random amplitude masks and some digital manipulations in the encryption and decryption procedure. We also analyze the encryption and decryption quality of the method proposed together with the influence of different random number generators. Numerical simulation has proved the validity of the architecture suggested.