Three-dimensional dynamic speckle simulation based on dynamic electric-field Monte Carlo and Ornstein-Uhlenbeck modeling.

Dynamic speckle simulation is an essential computational tool for investigating light scattering in dynamic media. However, current approaches predominantly depend either on mathematical models with imposed correlations or on tracking-based methods, both of which fall short of accurately representing three-dimensional speckle dynamics with physical rigor. Here, we present what is believed to be a novel three-dimensional dynamic speckle simulation framework that combines a dynamic electric-field Monte Carlo (dEMC) simulation with a complex-valued Ornstein-Uhlenbeck (OU) process. The dEMC resolves photon trajectories to calculate the electric field and its autocorrelation, which are subsequently utilized by the complex-valued OU process to efficiently synthesize time-integrated dynamic speckle patterns. This photon-tracking approach inherently provides depth-, polarization-, and scattering-order-resolved data, enabling a comprehensive analysis of the dynamic scattering light fields. Furthermore, we apply this simulation framework to quantify various physical characteristics of dynamic scattering, demonstrating strong agreement with theoretical predictions. Our framework offers a physically grounded and computationally efficient platform for exploring dynamic speckle phenomena and optimizing coherent light imaging systems.