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arXiv · 1303.3161

Real-time wavefront-shaping through scattering media by all optical feedback

Micha Nixon·Ori Katz·Eran Small·Yaron Bromberg·Asher A. Friesem·Yaron Silberberg·Nir Davidson
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Abstract

Focusing light through dynamically varying heterogeneous media is a sought-after goal with important applications ranging from free-space communication to nano-surgery. The underlying challenge is to control the optical wavefront with a large number of degrees-of-freedom (DOF) at timescales shorter than the medium dynamics. Recently, many advancements have been reported following the demonstration of focusing through turbid samples by wavefront-shaping, using spatial light modulators (SLMs) having >1000 DOF. Unfortunately, SLM-based wavefront-shaping requires feedback from a detector/camera and is limited to slowly-varying samples. Here, we demonstrate a novel approach for wavefront-shaping using all-optical feedback. We show that the complex wavefront required to focus through highly scattering samples, including thin biological tissues, can be generated at sub-microsecond timescales by the process of field self-organization inside a multimode laser cavity, without requiring electronic feedback or SLMs. This wavefront-shaping mechanism is more than five orders of magnitude faster than state-of-the-art, reaching the timescales required in many applications.

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Micha Nixon, Ori Katz, Eran Small, Yaron Bromberg, Asher A. Friesem, Yaron Silberberg, Nir Davidson. 2013-03-13. Real-time wavefront-shaping through scattering media by all optical feedback. https://doi.org/10.1038/nphoton.2013.248

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