Center for Relativistic Laser Science

2020 ABC

Laser-scanning reflection-matrix microscopy for myelin imaging

through intact mouse skull

Jin Hee Hong^1,2, Seokchan Yoon^1,2, Hojun Lee^1,2, Yong-Sik Lim³ and Wonshik Choi^1,2

We present a laser-scanning reflection-matrix microscopy (LS-RMM) that can correct sample-induced aberrations for up to 10,000 angular modes. LS-RMM combines the scanning of a laser focus and wide-field detection of electric fields backscattered from the sample. We coherently combine these measurements to construct a time-resolved reflection matrix with which the sample-induced aberrations are identified and corrected. The mouse skull is composed of complex microstructures that induce severe optical aberrations as well as strong multiple scattering noise. Here, using LS-RMM, we demonstrate aberration-free reflectance imaging of myelinated axons through an intact skull of a living mouse with an ideal diffraction-limited spatial resolution of 450 nm. We also demonstrate physical aberration correction for two-photon fluorescence imaging and clearly visualized dendritic spines of neurons in the mouse brain through an intact skull.