Switchable edge detection and depth perception with a phase-change image-processing metasurface

(GSST) for near-infrared optical image processing. In its crystalline state of GSST, the metasurface facilitates direct edge-enhanced imaging without a conventional 4-f system. Conversely, in the amorphous state, the same structure implements depth-sensitive point spread functions (PSFs) via a double-helix phase mask, translating axial displacement into angular variations for depth perception. This study provides a theoretical foundation and design methodology for developing highly integrated, programmable optical information processors based on metasurfaces, demonstrating great application potential for near-infrared intelligent imaging and 3D sensing applications.