Simultaneous suppression of scattering and aberration for ultra-high resolution imaging deep within scattering media

TL;DR

This paper introduces an experimental method to simultaneously suppress scattering and aberrations, enabling high-resolution imaging deep within scattering media like biological tissues.

Contribution

It presents a novel approach for identifying and correcting aberrations in highly scattering environments, achieving unprecedented imaging depth and resolution.

Findings

Achieved 600 nm resolution at 7 scattering mean free paths depth

Identified aberration correction maps for illumination and reflection paths

Demonstrated effective suppression of scattering and aberrations simultaneously

Abstract

Thick biological tissues give rise to not only the scattering of incoming light waves, but also aberrations of the remaining unscattered waves. Due to the inability of existing optical imaging methodologies to overcome both of these problems simultaneously, imaging depth at the sub- micron spatial resolution has remained extremely shallow. Here we present an experimental approach for identifying and eliminating aberrations even in the presence of strong multiple light scattering. For time-gated complex-field maps of reflected waves taken over various illumination channels, we identify two sets of aberration correction maps, one for the illumination path and one for the reflection path, that can preferentially accumulate the unscattered signal waves over the multiple-scattered waves. By performing closed-loop optimization for forward and phase- conjugation processes, we demonstrated a spatial resolution of 600 nm up to the unprecedented imaging depth of 7 scattering mean free paths.