Centimeter-scale achromatic cascaded metasurface hybrid lens with wavefront reconstruction for wide-field-of-view LWIR imaging

Long-wave infrared (LWIR) cameras are widely used in night vision, industrial inspection, medical diagnostics, and all-weather autonomous surveillance. However, compact LWIR imaging systems are still limited by chromatic aberrations in wide-field-of-view (FOV) operation, which hinders simultaneous achievement of broadband performance, wide-field imaging, and system compactness. In response, we propose a field-dependent wavefront reconstruction method for compact LWIR hybrid lenses, establishing a direct link between wavefront evolution and imaging performance. Based on this approach, an aberration-corrected LWIR imaging system is demonstrated using a cascaded metasurface hybrid lens (CMHL) composed of a refractive lens and two metasurfaces. Achromatic imaging is achieved within the bandwidth of 8–12 μm across a 50° FOV. Especially, the total optical path length of the thermal camera is 14.12 mm measured from the entrance pupil to the charge-coupled device (CCD) sensor plane. Imaging performance is characterized using a 1951 USAF resolution target at a 20 cm object distance, resolving features corresponding to 2 lp/mm. This work provides a promising route toward compact high-performance infrared imaging systems and enables the integration of optical design, wavefront engineering, and computational imaging.