Experimental research on JTC encryption system based on spiral phase mask and its characteristics

As a practical encryption method, the joint transform correlator (JTC) encryption method is one of the hot spots of optical encryption research. However, the key mask of JTC encryption system is usually random phase mask (RPM), the decryption effect of the image and the anti-attack ability need to be improved. In order to improve its performance, the spiral phase mask (SPM) in singular optics is used as the key mask of the JTC encryption system. Under the JTC encryption system, the influence of SPM's structure parameters on encryption-decryption effect was analyzed by means of theoretical analysis and numerical simulation. The influence of SPM and RPM on encryption-decryption effect and anti-attack ability were compared, and the initial experiment was conducted. The results indicated that the decryption effect is slightly improved when using SPM, the sensitivity of key is stronger, the key parameters are more, and the ability to resist the COA and CPA algorithm attack can be improved. The initial experiment results also verified the validity and correctness of our proposed method.