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arXiv · 2605.11454

Neural Refractive Index Primitives for Flame Field Reconstruction Using Background-Oriented Schlieren

Xinyi Lu·Wei Hu·Zizhou Liao·Zheng Wang·Yue Zhang·Jingxuan Li
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Abstract

An improved neural refractive-index-primitive method for background-oriented schlieren tomography is presented, enabling continuous three-dimensional reconstruction of refractive-index fields using a compact multilayer perceptron. The method adopts the refractive-index field as the sole neural primitive and integrates multiresolution hash encoding, automatic-discrete gradient losses, and a three-dimensional mask to enable fast convergence and high-resolution, spatially coherent reconstructions. Tests on numerical combustion phantoms and real flame data demonstrate accurate recovery of both large-scale structures and fine-scale turbulence, strong robustness to noise, and clear advantages over frequency-encoding-based and voxel-based reconstruction methods.

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Xinyi Lu, Wei Hu, Zizhou Liao, Zheng Wang, Yue Zhang, Jingxuan Li. 2026-05-12. Neural Refractive Index Primitives for Flame Field Reconstruction Using Background-Oriented Schlieren. https://arxiv.org/abs/2605.11454

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