Abstract

We propose a novel method to reconstruct non-line-of-sight (NLOS) scenes that combines polarization and time-of-flight light transport measurements. Unpolarized NLOS imaging methods reconstruct objects hidden around corners by inverting time-gated indirect light paths measured at a visible relay surface, but fail to reconstruct scene features depending on their position and orientation with respect to such surface. We address this limitation (known as the missing cone problem) by capturing the polarization state of light in time-gated imaging systems at picosecond time resolution, and introducing a novel inversion method that leverages directionality information of polarized measurements to reduce directional ambiguities in the reconstruction. Our method is capable of imaging features of hidden surfaces inside the missing cone space of state-of-the-art NLOS methods, yielding fine reconstruction details even when using a fraction of measured points on the relay surface. We demonstrate the benefits of our method in both simulated and experimental scenarios.

Paper

• Paper (Authors' version)
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Bibtex

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Acknowledgements

We thank the anonymous reviewers for their time and insightful comments, aswell as the members of the Graphics and Imaging Lab for their help with the manuscript. Our work was funded by the European Union's Defense Fund Program through the ENLIGHTEN project under grant agreement No. 101103242, and Oscar Pueyo-Ciutad was also partially supported by a FPU22/02432 predoctoral grant from the Ministerio de Ciencia, Innovación y Universidades.