Optical image authentication scheme using dual polarization decoding configuration

We report on an optical image authentication scheme using dual polarization decoding configuration. We examine a sparse encoding method based on image division to process the original image. Next, the sparse original image is separated into two noise-like structure images with random polarization parameters which are digitally encoded. During the decoding stage, the encoded images are sent into a dual polarization decoding configuration where a pixelated polarizer with sparse distribution of transmission angle is employed for image recovering. The proposed scheme avoids complicated recording of complex information and resolves the alignment problem of previous polarization encoding methods. Then we examine numerical simulations to show that the proposed scheme is well suited to recover the original image when decryption keys are correctly used. We find evidence that the verification system exhibits high robustness and flexibility against attacks and interference. We expect that these results might be useful for polarization-encoding based optical verification.