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arXiv · 2006.10856

Single-shot hybrid photoacoustic-fluorescent microendoscopy through a multi-mode fiber with wavefront shaping

Sylvain Mezil·Antonio M. Caravaca-Aguirre·Edward Z. Zhang·Philippe Moreau·Irène Wang·Paul C. Beard·Emmanuel Bossy
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Abstract

We present a minimally-invasive endoscope based on a multimode fiber that combines photoacoustic and fluorescence sensing. From the measurement of a transmission matrix during a prior calibration step, a focused spot is produced and raster-scanned over a sample at the distal tip of the fiber by use of a fast spatial light modulator. An ultra-sensitive fiber-optic ultrasound sensor for photoacoustic detection placed next to the fiber is combined with a photodetector to obtain both fluorescence and photoacoustic images with a distal imaging tip no larger than 250um. The high signal-to-noise ratio provided by wavefront shaping based focusing and the ultra-sensitive ultrasound sensor enables imaging with a single laser shot per pixel, demonstrating fast two-dimensional hybrid imaging of red blood cells and fluorescent beads.

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Sylvain Mezil, Antonio M. Caravaca-Aguirre, Edward Z. Zhang, Philippe Moreau, Irène Wang, Paul C. Beard, Emmanuel Bossy. 2020-06-18. Single-shot hybrid photoacoustic-fluorescent microendoscopy through a multi-mode fiber with wavefront shaping. https://arxiv.org/abs/2006.10856

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