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arXiv · 1709.09337

Focusing of light energy inside a scattering medium by controlling the time-gated multiple light scattering

Seungwon Jeong·Ye-Ryoung Lee·Sungsam Kang·Wonjun Choi·Jin Hee Hong·Jin-Sung Park·Yong-Sik Lim·Hong-Gyu Park·Wonshik Choi
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Abstract

The efficient delivery of light energy is a prerequisite for non-invasive imaging and stimulating of target objects embedded deep within a scattering medium. However, injected waves experience random diffusion by multiple light scattering, and only a small fraction reaches the target object. Here we present a method to counteract wave diffusion and to focus multiplescattered waves to the deeply embedded target. To realize this, we experimentally inject light to the reflection eigenchannels of a specific flight time where most of the multiple-scattered waves have interacted with the target object and maximize the intensity of the returning multiple-scattered waves at the selected time. For targets that are too deep to be visible by optical imaging, we demonstrated a more than 10-fold enhancement in light energy delivery in comparison with ordinary wave diffusion cases. This work will lay a foundation for enhancing the working depth of imaging, sensing, and light stimulation.

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Seungwon Jeong, Ye-Ryoung Lee, Sungsam Kang, Wonjun Choi, Jin Hee Hong, Jin-Sung Park, Yong-Sik Lim, Hong-Gyu Park, Wonshik Choi. 2017-09-27. Focusing of light energy inside a scattering medium by controlling the time-gated multiple light scattering. https://doi.org/10.1038/s41566-018-0120-9

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