Quantitative absorption tomography

TL;DR

Quantitative absorption tomography (QAT) is a novel computational method that reconstructs high-resolution 3D absorption maps from brightfield microscopy data, enabling detailed volumetric imaging without specialized hardware.

Contribution

QAT introduces a new computational framework for quantitative 3D absorption imaging from brightfield focal stacks, expanding microscopy capabilities into practical 3D histopathology.

Findings

Validated with spectrally selective phantoms

Demonstrated in living cells and plant tissue

Revealed 3D microarchitecture in human tissue

Abstract

Brightfield microscopy is central to wide range of biology, engineering, and histopathology; but is inherently limited to two-dimensional qualitative imaging, systematically investigating three-dimensional (3D) volumetric architecture. Here we introduce quantitative absorption tomography (QAT), a computational approach that quantitatively reconstructs high-resolution volumetric absorption coefficient distributions from brightfield focal stacks. By modeling absorption image formation in logarithmic intensity space and applying deconvolution with an absorption optical transfer function, QAT enables quantitative, spectrally resolved 3D absorption imaging without interferometry, sample rotation, or specialized hardware. We validate QAT using spectrally selective phantoms and demonstrate absorption-specific contrast complementary to refractive index tomography in living melanocytes and intact plant tissue. QAT further scales to millimeter-scale volumes of H&E-stained human tissue, revealing 3D histological microarchitecture without serial sectioning. This approach extends brightfield microscopy toward practical 3D histopathology.