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bioRxiv · 10.64898/2026.09.17.752288

Light Guiding in Scattering Media Using Focused Laser-Induced Acoustic Waves with an Open Elliptical Reflector

Liu, Y.·Shimada, K.·Kitamura, K.·Barrera, S.·Ye, M.·Ishijima, A.·Nakagawa, K.
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Abstract

Light scattering in biological tissue limits deep optical imaging. Acoustic waves can modulate optical properties and enhance photon delivery, but source-positioning requirements can complicate integration with other imaging modalities. Here, we present an open elliptical reflector that focuses laser-induced acoustic waves at a spatially separated target while maintaining open optical access. We characterized the spatiotemporal optical modulation induced by the localized acoustic focus. The system increased the local transmitted-light intensity by a factor of 2.57-fold through a 2-mm-thick 1% intralipid hydrogel and enhanced fluorescence signal under two-photon excitation through a 1.5-mm-thick scattering sample. These results demonstrate spatially separated, reflector-based acoustically assisted light guiding for enhanced light delivery and fluorescence excitation through scattering media.

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Liu, Y., Shimada, K., Kitamura, K., Barrera, S., Ye, M., Ishijima, A., Nakagawa, K.. 2026-09-18. Light Guiding in Scattering Media Using Focused Laser-Induced Acoustic Waves with an Open Elliptical Reflector. https://doi.org/10.64898/2026.09.17.752288

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