Target-Driven Ring-by-Ring Optimization of an Achromatic and Coma-Corrected Long-Wave Infrared Hybrid Metalens for Large Field of View Imaging

Long-wave infrared (LWIR) imaging is increasingly required in night vision, compact aerial platforms, and wearable systems, where the demand for lightweight and low-cost optics challenges traditional multi-element refractive lenses. Although metalenses offer strong miniaturization potential, their standalone bandwidth and wide-FOV performance remain constrained. To address these limitations, we propose a targetdriven, phase-gradient-aware ring-by-ring optimization for designing an achromatic and coma-corrected LWIR hybrid metalens with an 8.4mm diameter. The refractive geometry and wavelength-dependent metalens phase compensation is jointly optimized across the 8-12 μm band and a 41.4° full field of view. The resulting hybrid system, with a total track length of only 15.8 mm, delivers diffraction-limited focal spots with very small chromatic focal shifts, well-suppressed off-axis aberrations, and an MTF exceeding 0.37 at 20 lp/mm. Resolution-target imaging further demonstrates substantially clearer feature reproduction than a refractive-only lens. These results establish a viable route toward compact, lightweight, and high-performance LWIR imaging systems.