Double-Band Metasurface Infrared Optics for Integrated Multichannel Spectral Sensors

On the basis of the constructed multi-channel metasurface lens array, the design scheme of the integrated infrared spectrum detector is given. The integrated infrared spectrum detector consists of surface plasmon filter array, multi-channel metasurface lens array and infrared detector array. Effective detection of infrared absorption peaks and reference wavelengths of three gases. First, a metal hole-type surface plasmon filter array is designed. By adjusting the structural parameters of metal holes, the resonance characteristics of surface plasmons can be effectively adjusted, thereby realizing the adjustment of electromagnetic wave filtering characteristics. By adjusting the relevant structural parameters, four groups of metal hole arrays with different structural parameters are finally designed, which can achieve effective filtering of electromagnetic waves of the desired wavelength, and their transmittance is exceed 70%, and the FWHM of the transmission peak is less than 0.1 μm. Secondly, an infrared detector array composed of a photothermal conversion area and a thermoelectric conversion area is designed, and two high-efficiency electromagnetic wave absorbers based on the FP cavity resonance principle and the surface plasmon resonance principle are proposed. In the end, the difficulties of narrow-band filtering, wavefront manipulation, and efficient absorption of electromagnetic waves in the mid- and long-wave infrared band were successfully solved, laying a technical foundation for the development of integrated multi-component infrared gas sensors.