Multifunctional Metasurface: Holography and Spot Cloud Projection

Abstract Multifunctionality, integration, and miniaturization are the mainstream trends in modern device development. However, optical display and depth perception, essential for innovative applications like intelligent driving and mixed reality, are typically achieved separately in complex and bulky optical systems. Metasurfaces, ultrathin artificial optical surfaces with strong light–matter interaction capabilities at the nanoscale, offer a versatile platform for creating multifunctional, highly integrated, and miniaturized devices by fully exploring spatial multiplexing and utilizing variables like location, polarization, and frequency. In this study, a multifunctional metasurface that integrates meta‐holography with Dammann gratings is presented. By engineering the phase profile, the device can display specific holographic images in the Fresnel region while simultaneously producing a high‐density spot cloud with over 37 000 spots covering the entire half space. As a proof‐of‐concept, a projection and reconstruction experiment is performed to elaborate its potential for retrieving three‐dimensional (3D) spatial information of real scenarios. The simultaneous generation of display and point cloud holds significant promise for applications in cutting‐edge imaging technologies such as intelligent driving and robot vision.