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bioRxiv · 10.1101/2019.12.12.873877

Multi-photon attenuation-compensated light-sheet fluorescence microscopy

Veettikazhy, M.·Nylk, J.·Gasparoli, F.·Escobet-Montalban, A.·Hansen, A. K.·Marti, D.·Andersen, P. E.·Dholakia, K.
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Abstract

Attenuation of optical fields owing to scattering and absorption limits the penetration depth for imaging. Whilst aberration correction may be used, this is difficult to implement over a large field-of-view in heterogeneous tissue. Attenuation-compensation allows tailoring of the maximum lobe of a propagation-invariant light field and promises an increase in depth penetration for imaging. Here we show this promising approach may be implemented in multi-photon (two-photon) light-sheet fluorescence microscopy and, furthermore, be achieved in a facile manner utilizing a graded neutral density filter, circumventing the need for complex beam shaping apparatus. A "gold standard" system utilizing a spatial light modulator for beam shaping is used to benchmark our implementation. The approach will open up enhanced depth penetration in light-sheet imaging to a wide range of end users.

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Veettikazhy, M., Nylk, J., Gasparoli, F., Escobet-Montalban, A., Hansen, A. K., Marti, D., Andersen, P. E., Dholakia, K.. 2019-12-12. Multi-photon attenuation-compensated light-sheet fluorescence microscopy. https://doi.org/10.1101/2019.12.12.873877

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