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arXiv · 1302.5637

Optimal spatiotemporal focusing through complex scattering media

Jochen Aulbach·Alice Bretagne·Mathias Fink·Mickaël Tanter·Arnaud Tourin
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Abstract

We present a new approach for spatiotemporal focusing through complex scattering media by wave front shaping. Using a nonlinear feedback signal to shape the incident pulsed wave front, we show that the limit of a spatiotemporal matched filter can be achieved, i.e., the wave amplitude at the intended time and focus position is maximized for a given input energy. It is exactly what is also achieved with time-reversal. Demonstrated with ultrasound experiments, our method is generally applicable to all types of waves.

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Jochen Aulbach, Alice Bretagne, Mathias Fink, Mickaël Tanter, Arnaud Tourin. 2013-02-22. Optimal spatiotemporal focusing through complex scattering media. https://doi.org/10.1103/physreve.85.016605

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