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arXiv · 1908.01243

Focusing large spectral bandwidths through scattering media

Arturo G. Vesga·Matthias Hofer·Naveen Kumar Balla·Hilton B. De Aguiar·Marc Guillon·Sophie Brasselet
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Abstract

Wavefront shaping is a powerful method to refocus light through a scattering medium. Its application to large spectral bandwidths or multiple wavelengths refocusing for nonlinear bio-imaging in-depth is however limited by spectral decorrelations. In this work, we demonstrate ways to access a large spectral memory of a refocus in thin scattering media and thick forward-scattering biological tissues. First, we show that the accessible spectral bandwidth through a scattering medium involves an axial spatio-spectral coupling, which can be minimized when working in a confocal geometry. Second, we show that this bandwidth can be further enlarged when working in a broadband excitation regime. These results open important prospects for multispectral nonlinear imaging through scattering media.

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Arturo G. Vesga, Matthias Hofer, Naveen Kumar Balla, Hilton B. De Aguiar, Marc Guillon, Sophie Brasselet. 2019-08-03. Focusing large spectral bandwidths through scattering media. https://doi.org/10.1364/oe.27.028384

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