Non-interferometric key recording applied to a joint transform cryptosystem

In this Letter, we propose an opto-digital cryptosystem based on the joint transform correlator architecture without the need for a reference beam, phase-shifting techniques, or an additional window in the input plane. In this system, only two intensity recordings are necessary: the intensity of the key Fourier transform, and the joint power spectrum between the key and an arbitrary object in contact with a random phase mask. Combining them with the knowledge of their respective input modules, we implement a modified Gerch-berg-Saxton algorithm to recover the phase associated with the encryption key. The validity of our approach is demon-strated by computer simulations and experimental results. (c) 2023 Optica Publishing Group

Automated summary

In this letter, we propose an opto-digital cryptosystem based on the joint transform correlator architecture that eliminates the need for a reference beam, phase-shifting techniques, or an additional window in the input plane. The system only requires two intensity recordings: the intensity of the key Fourier transform and the joint power spectrum between the key and an arbitrary object with a random phase mask. By combining these recordings with the knowledge of their respective input modules, we use a modified Gerch-berg-Saxton algorithm to recover the phase associated with the encryption key. Computer simulations and experimental results demonstrate the validity of our approach.