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arXiv · 1403.3316

Non-invasive real-time imaging through scattering layers and around corners via speckle correlations

Ori Katz·Pierre Heidmann·Mathias Fink·Sylvain Gigan
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Abstract

Imaging with optical resolution through and inside complex samples is a difficult challenge with important applications in many fields. The fundamental problem is that inhomogeneous samples, such as biological tissues, randomly scatter and diffuse light, impeding conventional image formation. Despite many advancements, no current method enables to noninvasively image in real-time using diffused light. Here, we show that owing to the memory-effect for speckle correlations, a single image of the scattered light, captured with a standard high-resolution camera, encodes all the information that is required to image through the medium or around a corner. We experimentally demonstrate single-shot imaging through scattering media and around corners using incoherent light and various samples, from white paint to dynamic biological samples. Our lensless technique is simple, does not require laser sources, wavefront-shaping, nor time-gated detection, and is realized here using a camera-phone. It has the potential to enable imaging in currently inaccessible scenarios.

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Ori Katz, Pierre Heidmann, Mathias Fink, Sylvain Gigan. 2014-03-13. Non-invasive real-time imaging through scattering layers and around corners via speckle correlations. https://doi.org/10.1038/nphoton.2014.189

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