Development of a retroreflective model using differentiable rendering for mid-air image simulation

This study aims to enable the design of Aerial Imaging by Retro-Reflection (AIRR) systems entirely with simulation, eliminating physical prototyping. It is essential to accurately simulate mid-air image brightness and blur, which vary with observation angle and floating distance. We propose a retroreflective model and a differentiable rendering framework for accurate mid-air image simulation using ray tracing. Experiments show that our method improved SSIM by 0.069–0.183 and reduced LPIPS by 0.134–0.160 on average. It achieved higher structural and perceptual fidelity than the conventional model. This advancement enables more practical and accurate design of AIRR systems through simulation.