Light transport in complex scattering media: practical applications in 3D graphics, Sensing and Machine Learning

Accurate modeling of optical radiation propagation and interactions with complex materials such as biological tissues is a key ingredient in a number of practical applications from 3D photorealistic computer graphics rendering to sensing and biomedical visualization. This talk considers development of the novel algorithms and their subsequent implementations capable of dealing with multilayered translucent materials such as human skin. Firstly, we outline the detailed theoretical procedures required to solve both vector Radiative Transport and Raytracing equations simultaneously using light's orbital angular momentum beyond traditional radiometry. We created and successfully implemented a dual, unbiased Monte Carlo approach working in synergy for photon transport and path tracing techniques while executing on novel specialized NVIDIA’s Graphics Processing Units (GPUs) which support Compute Unified Device Architecture (CUDA) and Real-Time Raytracing (RTX) capabilities. Secondly, we focus on a number of practical applications such as 3D immersive demos and comprehensive examples of translucent material renderings of photorealistic quality, advanced optical sensing and biomedical visualization applications, etc. We perform a formal comparison of the developed algorithms with known analytical solutions, data obtained during in vivo clinical studies as well as previously developed offline rendering approaches. Finally, we show how recent developments in Machine Learning (ML) methods could assist with acquisition of material properties, corresponding BSSRDFs (Bidirectional scattering-surface distribution function) and aid with light transport calculations.