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Published January 20, 2017 | Submitted + Published + Supplemental Material
Journal Article Open

Sub-Nyquist sampling boosts targeted light transport through opaque scattering media


Optical time-reversal techniques are being actively developed to focus light through or inside opaque scattering media. When applied to biological tissue, these techniques promise to revolutionize biophotonics by enabling deep-tissue non-invasive optical imaging, optogenetics, optical tweezing, and phototherapy. In all previous optical time-reversal experiments, the scattered light field was well-sampled during wavefront measurement and wavefront reconstruction, following the Nyquist sampling criterion. Here, we overturn this conventional practice by demonstrating that even when the scattered field is under-sampled, light can still be focused through or inside scattering media. Even more surprisingly, we show both theoretically and experimentally that the focus achieved by under-sampling can be one order of magnitude brighter than that achieved under the well-sampling conditions used in previous works, where 3×3 to 5×5 pixels were used to sample one speckle grain on average. Moreover, sub-Nyquist sampling improves the signal-to-noise ratio and the collection efficiency of the scattered light. We anticipate that this newly explored under-sampling scheme will transform the understanding of optical time reversal and boost the performance of optical imaging, manipulation, and communication through opaque scattering media.

Additional Information

© 2017 Optical Society of America. Received 28 September 2016; revised 17 December 2016; accepted 19 December 2016 (Doc. ID 277662); published 11 January 2017. Funding: National Institutes of Health (NIH) (DP1 EB016986, R01 CA186567). We thank Dr. Konstantin Maslov for making the acoustic lens and Prof. James Ballard for proofreading the manuscript.

Attached Files

Published - optica-4-1-97.pdf

Submitted - 1611.01404.pdf

Supplemental Material - optica-4-1-97-s001.PDF


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August 19, 2023
October 20, 2023