Real-time in-vivo volumetric quantitative phase imaging with a compact handheld probe

Abstract

Quantitative phase imaging (QPI) offers label-free access to refractive index information of biological samples, which can achieve nanometer-level optical-path-length sensitivity with cellular/sub-cellular biophysical and histological details. Recently we introduced quantitative oblique back-illumination microscopy (qOBM) which works in epi-mode and uses multiply scattered photons within thick samples to yield quantitative phase in thick scattering tissues, thus overcoming QPI's long-standing limitation to thin transparent samples. qOBM provides real-time quantitative phase in 3D, and can be configured in a compact form factor. Here we describe a handheld qOBM probe, suitable for in-vivo diagnosic applications such as brain tumor assessment, dermatology, and more.