Design of a single-layer color waveguide display system based on a hybrid evolutionary algorithm

With the growing application scope of augmented reality (AR) display systems, monochromatic images no longer meet user requirements, while conventional color displays often lead to increased weight and cost due to structural complexity. To enable single-layer waveguide-based color displays, we propose a subwavelength waveguide structure for AR applications, blazed gratings as couplers to achieve light transmission through distinct high diffraction orders. By combining genetic algorithms with differential evolution strategies, we developed an improved hybrid optimization algorithm. The optimized system demonstrates average RGB diffraction efficiencies of 4.36%, 5.27%, and 3.97% at a 25° field of view (FOV), successfully implementing one-dimensional pupil expansion for AR display systems.