Monocrystalline silicon metasurfaces enabled aperture-robust reconstructive spectrometer for visible light.

The article focuses on the development of a compact reconstructive spectrometer based on monocrystalline silicon metasurfaces, designed to operate over a broad visible bandwidth of 400–800 nm with high reconstruction fidelity exceeding 99%. Unlike traditional grating-based spectrometers, this device uses engineered metasurface filters to encode spectral information without dispersive optics or mechanical components, enabling miniaturization and integration into imaging sensors. The spectrometer employs interleaved silicon nanopillar nanostructures to generate diverse, low cross-correlation spectral responses, enhancing reconstruction accuracy and stability. Experimental results demonstrate precise spectral reconstruction of narrowband and broadband light sources with low error and show that incorporating a focusing lens reduces angular sensitivity, maintaining performance across varying apertures (F/1.8 to F/8). This approach presents potential for creating broadband, high-accuracy, integrated hyperspectral imaging systems.