Small pixel infrared dual-color detector applying pixel-scale splitters integrated with infrared monochromatic detector

A novel small pixel infrared dual-color detector is presented using metasurface arrays splitters integrated on the monochromatic detector. Multiple physical fields coupling was used to clarify the optical transmission in metasurface arrays, beam splitting mechanism, and photoelectric conversion of infrared detectors. Beam splitters with wavelengths of 4 μm and 4.3 μm were designed, and the dual-color detection capability of HgCdTe infrared detector was calculated. The splitter efficiency reached as high as 70% for broadband infrared, and allowed a range of non-normal incidence for both wavelengths. The photoelectric response of coupled infrared detector was consistent with splitting results, and there was few crosstalk between the detector pixels. The calculation results of the photoelectric effect demonstrated that the integrated device could realize optical splitting, and infrared dual-color detection.