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arXiv · 2404.11415

Achromatic Full Stokes Polarimetry Metasurface for Full-color Polarization Imaging in the Visible

Abstract

Metasurfaces composed of anisotropic subwavelength structures provide an ultrathin platform for a compact, real-time polarimeter. However, applications in polychromatic scenes are restricted by the limited operating bandwidths and degraded imaging quality due to the loss of spectral information. Here, we demonstrated full-color polarization imaging based on an achromatic polarimeter consisting of four polarization-dependent metalenses. Boosted by an intelligent design scheme, arbitrary phase compensation and multi-objective matching are effectively compatible with a limited database. Broadband achromaticity for wavelengths ranging from 450 nm to 650 nm, with a relative bandwidth of nearly 0.435, is achieved for the full Stokes imaging. The experimental polarization reconstructed errors for operating wavelengths of 450 nm, 550 nm, and 650 nm are 7.5%, 5.9%, and 3.8%, respectively. The full-color and full-polarization imaging capability of the device is also verified with a customized object. The proposed scheme paves the way for further developing polarization imaging toward practical applications.

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Yueqiang Hu, Yi Zhang, Yuting Jiang, Quan Wang, Meiyan Pan, Huigao Duan. 2024-04-17. Achromatic Full Stokes Polarimetry Metasurface for Full-color Polarization Imaging in the Visible. https://arxiv.org/abs/2404.11415

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