Fig. 1. Modulation characteristics of micro-nano columns. (a) Relationship among phase, radius and height; (b) relationship among transmittance, radius and height; (c) basic unit of metalens; (d) phase and transmittance at a height of 5.5 μm

Fig. 2. On-chip integrated metalens on infrared detector. (a) Two-dimensional schematic of integrated metalens array on infrared detector; (b) single metalens structure

Fig. 3. Simulation results of metalens at different heights. (a) Relationship among focal length, focusing efficiency, and column height at a wavelength of 10 μm; (b) normalized light field intensity distribution along z-axis for different column heights [in Fig. 3(b), the black lines mark the range where the normalized field strength is greater than 0.95]

Fig. 4. Phase profile of metalens

Fig. 5. Simulation results of metalens with column height of 1.6 μm. (a) Relationship among focal length, focusing efficiency (z=123 µm), and wavelength for h=1.6 μm; (b) distribution of light field intensity in x-z plane; (c) normalized light field intensity distribution along x direction at z=123 µm [in Fig. 5(c), for clear display, the normalized field intensity of different wavelengths is shifted upward at equal interval]; (d) FWHM and theoretical diffraction limits

Fig. 6. Simulation results of processing tolerance and oblique incident light of metalens. (a) 10 simulation results of random distribution of column radius deviation values (focal length and focusing efficiency); (b) light field intensity distributions of incident light in different incident directions (θ is angle between obliquely incident light and the z-axis)