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arXiv · 2605.05747

Programmable spatial coherence tomography: diffraction-limited three-dimensional reflection imaging under modulated monochromatic illumination

Herve Hugonnet·Jieun Choi·Gyoung Hwan Kim·Chulmin Oh·Jimin Cho·Chungha Lee·Su-Jin Shin·Sujin Park·Bon-Kyoung Koo·Wang-Yuhl Oh·Pilhan Kim·YongKeun Park
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Abstract

Depth sectioning in reflection microscopy has predominantly relied on temporal coherence gating. Here we show that volumetric reflection tomography at diffraction-limited resolution can be achieved under monochromatic illumination by engineering spatial, rather than temporal, coherence. In programmable spatial coherence tomography (PSCT), a sequence of pupil-coded illumination patterns with angular-spectrum diversity generates measurement redundancy enabling the system to calibrate itself, jointly retrieving aberrations, illumination profiles, and sample motion without guide stars or modal priors. We demonstrate label-free volumetric imaging of thick human tissues, organoids, frequency-resolved dynamic contrast, and high-resolution in vivo brain imaging through a cranial window. These results position PSCT as an alternative to temporal coherence based reflection imaging in complex biological systems.

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Herve Hugonnet, Jieun Choi, Gyoung Hwan Kim, Chulmin Oh, Jimin Cho, Chungha Lee, Su-Jin Shin, Sujin Park, Bon-Kyoung Koo, Wang-Yuhl Oh, Pilhan Kim, YongKeun Park. 2026-05-07. Programmable spatial coherence tomography: diffraction-limited three-dimensional reflection imaging under modulated monochromatic illumination. https://arxiv.org/abs/2605.05747

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