Dual-functional metasurface image-processor

Optical image processing has the advantages of fast and parallel operation. One single-layered metasurface is designed to implement the optical imaging and edge detection of image. The dual-functional image processing is conducted without the aid of 4f system and it is switched only by the handedness of incident circularly polarized light. The designed metasurface consists of silicon nanopillars and the optimized nanopillars are equivalent to half-wave plates with the transmittance of 87%. The simulation and experimental results verify the performance of metasurface. The integrated optical metasurface enables the extremely simple image processing system and it paves the way for the applications of metasurfaces in parallel image processing and optical integrating.