摘要 |
A method and apparatus of encrypting optical images and storing these images in memory using random phase encoding is presented. The encryption technique uses random phase encoding in both the input plane and the Fourier plane. Each image is encrypted and can be read out by a unique code or a universal code. The image to be encrypted is first multiplied by a random phase function. The Fourier transform of the product of the image and the random phase function is then multiplied by another random phase function in the Fourier domain. Taking the inverse Fourier transform, an encrypted image in the output plane is obtained. Each encrypted image can be stored in optical memory. The encryption process of the present invention can be done optically or electronically with one or two dimensional functions for encryption. Further, the image can be phase encoded (optically or digitally) prior to the encryption process, with a phase reading technique employed to obtain the original decrypted image. Also, a joint transform correlator may be used for the encryption and/or decryption of the present invention. It will be appreciated that a variety of well known methods can be used to store or display the encrypted images.
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