Bayati Elyas, Pestourie Raphaël, Colburn Shane, Lin Zin, Johnson Steven G, Majumdar Arka
Department of Electrical and Computer Engineering, University of Washington, Seattle, WA 98195, USA.
Department of Mathematics, MIT, Cambridge, MA 02139, USA.
Nanophotonics. 2021 Sep 24;11(11):2531-2540. doi: 10.1515/nanoph-2021-0431. eCollection 2022 Jun.
We report an inverse-designed, high numerical aperture (∼0.44), extended depth of focus (EDOF) meta-optic, which exhibits a lens-like point spread function (PSF). The EDOF meta-optic maintains a focusing efficiency comparable to that of a hyperboloid metalens throughout its depth of focus. Exploiting the extended depth of focus and computational post processing, we demonstrate broadband imaging across the full visible spectrum using a 1 mm, f/1 meta-optic. Unlike other canonical EDOF meta-optics, characterized by phase masks such as a log-asphere or cubic function, our design exhibits a highly invariant PSF across ∼290 nm optical bandwidth, which leads to significantly improved image quality, as quantified by structural similarity metrics.
我们报道了一种通过逆向设计的、高数值孔径（约0.44）、具有扩展焦深（EDOF）的超颖光学元件，其呈现出类似透镜的点扩散函数（PSF）。该EDOF超颖光学元件在其整个焦深范围内保持与双曲面超透镜相当的聚焦效率。利用扩展焦深和计算后处理技术，我们展示了使用一个1毫米、f/1的超颖光学元件在整个可见光谱范围内的宽带成像。与其他以诸如对数非球面或立方函数等相位掩模为特征的典型EDOF超颖光学元件不同，我们的设计在约290纳米的光学带宽内呈现出高度不变的PSF，这导致图像质量显著提高，如通过结构相似性指标所量化的那样。
