Epi-illumination quantitative phase imaging (QPI) and 3D refractive index (RI) tomography in thick scattering samples with quantitative oblique back-illumination microscopy

Abstract

Quantitative phase imaging (QPI) and 3D refractive index (RI) tomography are important tools in biomedicine that yield label-free access to cellular and subcellular structures with unprecedented clarity. However, implementation of these technologies involves a transmission-based geometry which requires thin samples. Here we describe quantitative oblique back illumination microscopy (qOBM), which overcomes this significant limitation and achieves epiillumination quantitative phase imaging and 3D RI tomography in thick samples, including intact thick tissues. In this presentation, we will describe the method in detail and show results from thick samples including intact whole mouse brains and organoids. qOBM opens the door to many exciting new applications in biomedicine.