Optimizing the uniformity and efficiency of AR waveguide displays with an open-source beam tracing method

Low optical efficiency and poor brightness uniformity are presently two major challenges in waveguide-based augmented reality (AR) displays, often presenting a trade-off that limits the system's performance. Addressing these issues requires a simulation framework that is both physically accurate and computationally efficient. In this paper, we present a framework for optimizing the efficiency and uniformity of waveguide-based AR systems, built on a newly developed open-source beam tracing model. The algorithm accounts for grating multi-interaction effects and traces each beam only once for reuse during optimization, while parallel CPU (central processing unit) processing and data compression are employed to accelerate the simulation speed. The proposed method achieves an average evaluation time of 0.417 seconds, which is more than 100 times faster than non-sequential ray tracing tools, making it highly desirable for iterative waveguide design and optimization.