A coupled multiple-sphere T-matrix and Monte Carlo ray-tracing approach for curing-geometry prediction and contour compensation in high-solid-loading ceramic vat photopolymerization

High-solid-loading ceramic vat photopolymerization (VPP) enables dense ceramic components, but dimensional control remains difficult because particle-induced scattering redistributes exposure energy and alters curing geometry. Existing working-curve descriptions, simplified scattering models, and empirical compensation schemes provide only limited predictive connection between slurry optical characteristics and printed feature dimensions when dependent scattering becomes significant. Here, a coupled multiple-sphere T-matrix and Monte Carlo ray-tracing (MSTM-MCRT) approach was developed for curing-geometry prediction and contour compensation. Full-wave MSTM calculations were used to obtain dependent-scattering radiative properties, including scattering, absorption, and angular redistribution, for dense particle assemblies. These properties were then incorporated into a three-dimensional MCRT model to predict spatial dose distribution, cure depth, cure width, and cross-sectional curing contour. The predicted curing dimensions were further converted into local boundary offsets for model-guided compensation of contour-defined microfeatures and internal channels. For the investigated Al 2 O 3 –resin slurry over 10–50 vol% solid loading, comparison with independent-scattering approximation and structure-factor approximation baselines shows that the advantage of MSTM becomes especially evident at Φ ≥ 40 vol%. Experiments showed that the predicted cure depth and cure width remained within the ±5% reference band in the relative error analysis. The approach also compensated square openings, circular openings, and a serpentine microchannel, yielding a 791 μm opening for an 800 μm target. This study establishes a physics-based route from dense-particle optical response to curing-geometry prediction and contour compensation, providing guidance for exposure design, slurry-formulation assessment, and dimensional control in high-solid-loading ceramic VPP.