Optical encryption using structural uncorrelated characteristics of biological scattering media

ABSTRACT Inspired by the unique internal structures with inherent anisotropy in biological tissues and their dynamic scattering characteristic, a simple and easy-to-fabricate optical encryption technique using structural uncorrelated characteristics of biological tissues was proposed. It can generate unique keys with the random characteristics of the tissues and transforms multiple image plaintexts into speckle-like ciphertexts. The optical encryptions of grayscale images are demonstrated utilizing the uncorrelated characteristics of shallot and chicken breast respectively. Ciphertext-only-attack is resisted by phase retrieval due to the inherent dynamic randomness of biological tissues and the complexity of the plaintexts. Besides, once the unique PSF keys is recorded by the optical setup, the encryption can be accomplished, either online using the setup, or offline through performing convolutions on the plaintexts with pre-recorded uncorrelated PSFs to yield ciphertexts. Therefore, it is very secure, simple, and flexible to guarantee the promising potentials for information encryption of grayscale images and/or videos.