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High-resolution non-line-of-sight imaging employing active focusing

Cao, Ruizhi and de Goumoens, Frederic and Blochet, Baptiste and Xu, Jian and Yang, Changhuei (2022) High-resolution non-line-of-sight imaging employing active focusing. Nature Photonics, 16 (6). pp. 462-468. ISSN 1749-4885. doi:10.1038/s41566-022-01009-8.

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Non-line-of-sight (NLOS) imaging is a rapidly developing research direction that has significant applications in autonomous vehicles, remote sensing and other areas. Existing NLOS methods primarily depend on time-gated measurements and sophisticated signal processing to extract information from scattered light. Here we introduce a method that directly manipulates light to counter the wall’s scattering. This method, termed unseen non-line-of-sight casted optical aperture visibility-enhanced return (UNCOVER) focusing, operates by actively focusing light onto the hidden target using wavefront shaping. By raster scanning that focus, we can actively image the hidden object. The focus thus formed is near diffraction limited and can be substantially smaller than the object itself, thereby enabling us to perform NLOS imaging with unprecedented resolution. We demonstrate that a resolution of ~0.6 mm at a distance of 0.55 m is achievable in UNCOVER, giving us a distance-to-resolution ratio of ~970.

Item Type:Article
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URLURL TypeDescription ReadCube access
Cao, Ruizhi0000-0003-3385-446X
de Goumoens, Frederic0000-0001-7161-8762
Blochet, Baptiste0000-0003-1457-4542
Xu, Jian0000-0002-4743-2471
Yang, Changhuei0000-0001-8791-0354
Additional Information:© 2022 Springer Nature Limited. Received 22 July 2021. Accepted 21 April 2022. Published 30 May 2022. Issue Date June 2022. This research is supported by Caltech Sensing to Intelligence (S2I) (award no. 13520296) to R.C., F.G., B.B., J.X. and C.Y. Contributions. C.Y. conceived the idea. R.C., B.B. and J.X. developed the idea. R.C. designed and developed the experimental protocol and setup. R.C. conducted the theoretical analysis, conducted the experiments and wrote the simulation and experiment codes. F.G. helped with the simulation code. All the authors contributed to the preparation of the manuscript. Data availability. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. Code availability. The code that supports the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. Competing interests. The authors declare the following competing interests: in October 2020, California Institute of Technology filed a patent for UNCOVER (US application no. 63/090,429), which covered the concept and implementation of the UNCOVER system described here. Peer review information. Nature Photonics thanks Daniele Faccio, Allard Mosk and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Funding AgencyGrant Number
Caltech Sensing to Intelligence (S2I)13520296
Issue or Number:6
Record Number:CaltechAUTHORS:20220531-843943000
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Official Citation:Cao, R., de Goumoens, F., Blochet, B. et al. High-resolution non-line-of-sight imaging employing active focusing. Nat. Photon. 16, 462–468 (2022).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:114967
Deposited By: George Porter
Deposited On:01 Jun 2022 16:37
Last Modified:01 Jun 2022 16:37

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