Ultraspectral Imaging Based on Metasurfaces with Freeform Shaped Meta‐Atoms

Metasurfaces have an exceptional capacity to manipulate the phase, amplitude, polarization, or spectrum of light. However, unit cells, meta-atoms, metasurfaces are conventionally designed using regular shapes, limiting performance improvement. The utilization with freeform shaped meta-atoms for on-chip ultraspectral imaging is proposed, where patterns generated controllable feature sizes and boundary curvatures feasible fabrication. These broaden design diversity enrich metasurface-unit spectral response complicated Bloch modes, thus improving enhanced recovery precision broadband spectra smaller center-wavelength deviation narrowband spectra. A snapshot imaging, 356 × 436 pixels experimentally demonstrated. Spectral resolution state-of-the-art, at 0.5 nm, mean fidelity reconstruction a standard color board reaches 98.78%. results support future applications in field precise intelligent perception. Moreover, generating method also benefits forward inverse designs high-performance metasurfaces.