Imaging through a projection screen using bi-stable switchable diffusive photon sieves.

We designed and demonstrated a liquid crystal (LC) photon sieve (PS) device which can be integrated on a conventional diffusive projection screen and switched to record images. The device fabrication method and assembly of it by using Smectic A (SmA) LC material is also presented. In the PS state, the device comprises diffusive elements, which simultaneously allow to image the scene in front of the device on a camera sensor behind itself and display another image projected onto the device. The image captured using the PS has acceptable visual quality. The projected images, from an external picture source, on the diffusive elements can be observed with a quality comparable to the full scattering state. The projected images are observed with almost no detectable features of the device at the observation distance. The device offers a built-in solution for eye-to-eye video conferencing applications.