Lightweight Spectro‐Polarimetric Imaging Enabled by Freely Height‐Varying Metasurface via Two‐Photon Polymerization Lithography

ABSTRACT The pursuit of high‐dimensional optical information, particularly spectrum and polarization, has been a persistent goal in both scientific research and engineering applications. However, conventional spectro‐polarimetric imaging systems are typically constrained by bulky hardware, complex optical configurations, and heavy computational burdens, which severely limit their deployment on miniaturized platforms. In this study, we propose a lightweight spectro‐polarimetric imaging method enabled by a height‐varying metasurface via two‐photon polymerization lithography, where out‐of‐plane height modulation and in‐plane geometric shapes are jointly exploited to achieve a broader spectral modulation range and different polarimetric responses. By combining the designed metasurface with a newly built reconstruction algorithm, spectro‐polarimetric images are successfully reconstructed from a single grayscale image, with an average polarization angle error of 3.02° for uniform objects and an average PSNR of 35.86 dB, SSIM of 0.93, and spectrum fidelity of 98.45% for a complex object, demonstrating the high reconstruction quality of the proposed method. This work provides a compact and efficient route toward snapshot acquisition of high‐dimensional light information, offering strong potential for integration into miniaturized imaging platforms.