Polarization‐Assisted Visual Secret Sharing Encryption in Metasurface Hologram

Abstract

Secret sharing is an advanced encryption method that distributes the secret information into multiple participants and only the pre-designed subsets of authorized participants can recover the secret by gathering their independent sub-information. In this paper, we further expand the security level of secret sharing using electromagnetic manners and present a simple platform for the realization and direct observation of secret sharing encryption using metasurface hologram. As a proof of concept, a polarization-assisted secret sharing phase encoding method by integrating visual secret sharing scheme with phase encoding technology using orthogonally polarization-multiplexing metasurface is experimentally presented. Our method achieves its encryption security and decryption simplicity by hiding the secret information into a pair of orthogonal polarization channels ensuring that the secret information is direct decryption as the two channels participate simultaneously while fully concealed in single channel. This scheme may pave a new route for future information encryption, hiding and authentication.