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arXiv · 2509.20676

Transfer-Function Approach to Substrate-Enhanced Diffraction Tomography

Tongyu Li·Yi Shen·Dashan Dong·Danchen Jia·Jianpeng Ao·Ji-Xin Cheng·Lei Tian
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Abstract

Forward and backward scattering provide complementary volumetric and interfacial information, yet conventional three-dimensional (3D) imaging typically accesses only one. In this Letter, we present a substrate-enhanced diffraction tomography approach that simultaneously recovers both channels under multi-angle epi-illumination.This geometry captures one forward- and two backward-scattering bands in axially symmetric Fourier regions, where their complementary coverage enables phase-absorption separation in a non-Hermitian spectrum. Explicit 3D transfer functions are derived for both channels, and an axial Kramers-Kronig relation is established to incorporate substrate-induced boundary conditions in a unified framework. Our results establish a label-free, high-resolution 3D imaging modality that surpasses the limits of existing methods.

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Tongyu Li, Yi Shen, Dashan Dong, Danchen Jia, Jianpeng Ao, Ji-Xin Cheng, Lei Tian. 2025-09-25. Transfer-Function Approach to Substrate-Enhanced Diffraction Tomography. https://doi.org/10.1364/optica.580672

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