Image encryption using arbitrary modes of Hermite-Gaussian beams

In recent years, use of structured light beams in information processing has gained considerable interest due to their unique intensity and phase distributions. For encoding, optical encryption techniques utilize the spatial distributions of light. Image/data encryption through phase encoding requires complicated interferometric set-up while polarization encoding needs multiple intensity recordings. Such constraints create difficulties during optical implementation. To address these issues, we propose a method of image encryption that requires single recording of intensity distribution containing different modes of a Hermite-Gaussian (HG) beam. In this scheme, the freedom of independent and random choice of different modes of HG beam for encoding enhances the security. Further, we demonstrate an Arnold transformation-based information-sharing scheme, where the information of the decryption key is not required to be shared with the receiver for decryption. To check the effectiveness of the proposed architecture, various performance measure parameters such as correlation coefficient, mean square error, and peak signal-to-noise ratio between the plaintext and decrypted image have been computed.