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arXiv · 1508.01305

Super-resolution photoacoustic fluctuation imaging with multiple speckle illumination

Thomas Chaigne·Jérôme Gateau·Marc Allain·Ori Katz·Sylvain Gigan·Anne Sentenac·Emmanuel Bossy
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Abstract

In deep tissue photoacoustic imaging, the spatial resolution is inherently limited by acoustic diffraction. Moreover, as the ultrasound attenuation increases with frequency, resolution is often traded-off for penetration depth. Here we report on super-resolution photoacoustic imaging by use of multiple speckle illumination. Specifically, we show that the analysis of second-order fluctuations of the photoacoustic images combined with image deconvolution enables resolving optically absorbing structures beyond the acoustic diffraction limit. A resolution increase of almost a factor 2 is demonstrated experimentally. Our method introduces a new framework that could potentially lead to deep tissue photoacoustic imaging with sub-acoustic resolution.

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Thomas Chaigne, Jérôme Gateau, Marc Allain, Ori Katz, Sylvain Gigan, Anne Sentenac, Emmanuel Bossy. 2015-08-06. Super-resolution photoacoustic fluctuation imaging with multiple speckle illumination. https://doi.org/10.1364/optica.3.000054

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