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arXiv · 2105.00160

Inverse Designed Extended Depth of Focus Meta-Optics for Broadband Imaging in the Visible

Elyas Bayati·Raphael Pestourie·Shane Colburn·Zin Lin·Steven G. Johnson·Arka Majumdar
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Abstract

We report an inverse-designed, high numerical aperture (~0.44), extended depth of focus (EDOF) meta-optic, which exhibit 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 ~290nm optical bandwidth, which leads to significantly improved image quality, as quantified by structural similarity metrics.

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Elyas Bayati, Raphael Pestourie, Shane Colburn, Zin Lin, Steven G. Johnson, Arka Majumdar. 2021-09-30. Inverse Designed Extended Depth of Focus Meta-Optics for Broadband Imaging in the Visible. https://doi.org/10.1515/nanoph-2021-0431

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