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Depuis la fin des années 2000, les techniques de modulation du front d’onde ont connu un grand essor pour les applications aux milieux complexes. Ces milieux, en particulier les milieux biologiques épais et les fibres optiques multimodes, mélangent la lumière rendant l’imagerie impraticable. En permettant de focaliser la lumière ou de reconstruire des signaux à travers ces milieux, le contrôle du front d’onde a permis de nombreuses avancées pour l’imagerie et les télécommunications.

Acousto-optic (AO) imaging is an in-depth optical imaging technique of highly scattering media. One challenging end-application for this technique is to perform imaging of living biological tissues. Indeed, because it relies on coherent illumination, AO imaging is sensitive to speckle decorrelation occurring on the millisecond time scale. Camera-based detections are well suited for in vivo imaging provided their integration time is lower than those decorrelation time scales. We present Fourier transform acousto-optic imaging combined with off-axis holography, which relies on plane waves and long-duration pulses. We demonstrate, for the first time to the best of our knowledge, a two-dimensional imaging system fully compatible with in vivo imaging prerequisites. The method is validated experimentally by performing in-depth imaging inside a multiple scattering sample.

Performing linear operations using optical devices is a crucial building block in many fields ranging from telecommunications to optical analog computation and machine learning. For many of these applications, key requirements are robustness to fabrication inaccuracies, reconfigurability, and scalability. We propose a way to perform linear operations using complex optical media such as multimode fibers or scattering media as a computational platform driven by wavefront shaping. Given a large random transmission matrix representing light propagation in such a medium, we can extract any desired smaller linear operator by finding suitable input and output projectors. We demonstrate this concept by finding input wavefronts using a spatial light modulator that cause the complex medium to act as a desired complex-valued linear operator on the optical field. We experimentally build several 16×16 operators and discuss the fundamental limits of the scalability of our approach. It offers the prospect of reconfigurable, robust, and easy-to-fabricate linear optical analog computation units.