Temporal Integral Holography with an Intelligent Metasurface

Intelligent metasurfaces represent a pivotal advancement in dynamic holographic imaging, significantly enhancing holographic capacity. However, existing reconfigurable holographic systems are limited by factors such as low resolution and limited storage density, highlighting the necessity of innovative solutions. To address these limitations, we propose a holographic imaging scheme based on temporal integral holography (TIH), implemented with a 16 × 16 radiation-type metasurface controlled by a field-programmable gate array (FPGA) with embedded PIN diodes, operating without external feeding. The FPGA is programmed to generate discrete phase distributions that dynamically steer holographic focal points. Through temporal integration, these points accumulate to form a 5 × 5 focal array that serves as a basis for reconstructing arbitrary images. This scheme enables the flexible generation of diverse visual symbols on demand, including the complete set of letters, numbers, and symbols on a standard keyboard, thereby meeting the requirements for complex visual patterns and facilitating information transmission through the compact encoding of messages into customized spatial distributions. By eliminating the need for precomputed large-area phase profiles, the method could simplify system design and enhance flexibility. Simulations and experimental results demonstrate excellent agreement, confirming high-fidelity image reconstruction with minimal crosstalk. Overall, the proposed strategy offers a cost-effective, scalable solution for applications in intelligent sensing, next-generation wireless communications, and secure information encryption.