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arXiv · 2608.21890

Feature-domain Fourier ptychographic tomography with dark-field illumination

Chao Tan·Fangrui Lu·Sechan Park·Hyeonseo Na·Chanseok Lee·Chang-Seok Kim·Jeesu Kim·Hwidon Lee·Mooseok Jang
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Abstract

Fourier ptychographic tomography (FPT) is an implementation of intensity diffraction tomography that reconstructs three-dimensional (3D) refractive-index (RI) distributions from angle-varied intensity measurements. The distinctive advantage of FPT emerges when incorporating dark-field illumination, which extends the space-bandwidth product toward gigavoxel-scale volumetric imaging, yet dark-field measurements are highly sensitive to system imperfections and often have low signal-to-noise ratios. Here, we propose feature-domain FPT (FD-FPT), which evaluates data fidelity after feature extraction and is optimized using automatic differentiation. In numerical and experimental tests, FD-FPT resolves structures near the synthetic-aperture cutoff far more reliably than the spatial-domain baseline (SD-FPT). Notably, in a whole-mount Oedogonium specimen, the reticulate chloroplast network and transverse septa were resolved only by FD-FPT. We further demonstrate a 1.81-gigavoxel RI reconstruction of a mouse adrenal gland section across a 1.66 by 1.40 square millimeter field of view, establishing FD-FPT as a practical route to label-free volumetric imaging that combines millimeter-scale coverage with cellular-scale structural contrast.

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Chao Tan, Fangrui Lu, Sechan Park, Hyeonseo Na, Chanseok Lee, Chang-Seok Kim, Jeesu Kim, Hwidon Lee, Mooseok Jang. 2026-08-22. Feature-domain Fourier ptychographic tomography with dark-field illumination. https://arxiv.org/abs/2608.21890

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