Optical image encryption based on two beams’ interference

We proposed a method for optical image encryption on the basis of interference theory. An optical image can be produced by the interference of two beams passed two different masks. One of the masks can only modulate the phase of the beam and another can only modulate the amplitude of the beam. The encryption method is quite simple and does not need iterative algorithm. The results of simulation coincide with our method and demonstrate the feasibility of this method.