Li Zhaoyi, Pestourie Raphaël, Park Joon-Suh, Huang Yao-Wei, Johnson Steven G, Capasso Federico
Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nat Commun. 2022 May 3;13(1):2409. doi: 10.1038/s41467-022-29973-3.
Meta-optics has achieved major breakthroughs in the past decade; however, conventional forward design faces challenges as functionality complexity and device size scale up. Inverse design aims at optimizing meta-optics design but has been currently limited by expensive brute-force numerical solvers to small devices, which are also difficult to realize experimentally. Here, we present a general inverse-design framework for aperiodic large-scale (20k × 20k λ) complex meta-optics in three dimensions, which alleviates computational cost for both simulation and optimization via a fast approximate solver and an adjoint method, respectively. Our framework naturally accounts for fabrication constraints via a surrogate model. In experiments, we demonstrate aberration-corrected metalenses working in the visible with high numerical aperture, poly-chromatic focusing, and large diameter up to the centimeter scale. Such large-scale meta-optics opens a new paradigm for applications, and we demonstrate its potential for future virtual-reality platforms by using a meta-eyepiece and a laser back-illuminated micro-Liquid Crystal Display.
超表面光学在过去十年中取得了重大突破；然而，随着功能复杂性和器件尺寸的增加，传统的正向设计面临挑战。逆向设计旨在优化超表面光学设计，但目前受到昂贵的蛮力数值求解器的限制，只能用于小型器件，而且在实验上也难以实现。在此，我们提出了一种用于三维非周期性大规模（20k×20kλ）复杂超表面光学的通用逆向设计框架，该框架分别通过快速近似求解器和伴随方法减轻了模拟和优化的计算成本。我们的框架通过代理模型自然地考虑了制造约束。在实验中，我们展示了在可见光下工作的具有高数值孔径、多色聚焦和高达厘米尺度大直径的像差校正金属透镜。这种大规模超表面光学为应用开辟了新的范式，并且我们通过使用超表面目镜和激光背照式微型液晶显示器展示了其在未来虚拟现实平台中的潜力。
