Visible-to-near-infrared spectrum reconstruction with dielectric metasurfaces

The miniaturization of spectrometers has received much attention in recent years. The rapid development of metasurfaces has provided a new avenue for creating more compact and lightweight spectrometers. However, most metasurface-based spectrometers operate in the visible light region, with much less research on near-infrared wavelengths. This is possibly caused by the lack of effective metasurface filters for the near-infrared light. We design and fabricate a polarization-insensitive amorphous silicon metasurface that exhibits unique transmission spectra in parts of the visible and near-infrared wavelengths. By passing the light to be measured through a metasurface filter array and measuring the transmitted power, we achieve the precise reconstruction of unknown spectra in the visible and near-infrared range (450–950 nm) using an algorithm matched to the filter model. Our approach is a step towards miniaturized spectrometers within the visible-to-near-infrared range based on metasurface filter arrays.