Secure sharing method for a secret binary image and its reconstruction system

In this paper, an encryption method to share a secret binary image is proposed. It divides the image to be encrypted into an arbitrary number of images and encrypts them using XOR process with different binary random images which was prepared by the means of the XOR process, too. Each encrypted slice image can be distributed to the authenticated ones. However, we transfer the encrypted images to the binary phase masks to strengthen the security power, that means phase masks can not be copied with general light-intensity sensitive tools such as CCDs or cameras. For decryption, we used the Mach-Zehnder interferometer in which linearly polarized two light beams in orthogonal direction, respectively. The experimental result proved the efficiency of the proposed method.