Scattering correcting wavefront shaping for three-photon microscopy

TL;DR

This paper introduces a wavefront shaping method guided by three-photon fluorescence to correct scattering in deep tissue imaging, enabling improved focus and imaging through scattering layers and biological tissues.

Contribution

It presents a simple continuous optimization algorithm for scattering correction in 3P microscopy, including a fast phase estimation scheme for quicker correction.

Findings

Successful focusing behind scattering layers

Imaging through a mouse skull achieved

Fast phase estimation increases correction speed

Abstract

Three-photon (3P) microscopy is getting traction due to its superior performance in deep tissues. Yet, aberrations and light scattering still pose one of the main limitations in the attainable depth ranges for high-resolution imaging. Here, we show scattering correcting wavefront shaping with a simple continuous optimization algorithm, guided by the integrated 3P fluorescence signal. We demonstrate focusing and imaging behind scattering layers and investigate convergence trajectories for different sample geometries and feedback non-linearities. Furthermore, we show imaging through a mouse skull and demonstrate a novel fast phase estimation scheme that substantially increases the speed at which the optimal correction can be found.