SiM-SHDR: single-layer metasurface for snapshot high dynamic range imaging

Imaging systems based on metasurfaces have advantages in terms of integration and flexibility. Here, we present a single-layer metasurface for snapshot high dynamic range (HDR) Imaging scheme (SiMSHDR). The metasurface can integrate functions of multiple components found in traditional HDR imaging systems. Benefiting from the polarization-independent full-space amplitude and phase control mechanism, the single-layer metasurface is capable of capturing multiple high-fidelity images with different levels of intensity in a single shot. After fusing the images, the dynamic range of the pictures can be effectively extended. Using dual-channel image capture configuration with an intensity ratio of 10:1, the dynamic range can theoretically be enhanced by up to 20 dB. Experimental results in our demonstrated imaging system show the dynamic range improvement can reach 17.5 dB and even more. This metasurface design maintains a similar weight and volume to traditional single-image acquisition systems, making it ideal for lightweight, ultra-compact and real-time HDR imaging in applications like surveillance, industrial manufacturing, and driving.