Design and virtual prototyping of a compact augmented reality system with 2D diffraction grating

This paper presents a computer model of an optically transparent augmented reality system built using a configuration with two diffraction elements. A distinctive feature of this device is that the second diffraction element is a two-dimensional diffraction grating that combines functions of beam expansion and image extraction from the light guide. The technology for manufacturing two-dimensional diffraction gratings is presented. Formulas for calculating the direction of beams diffracted by the diffraction gratings, including the two-dimensional grating, are proposed. Two ray-tracing algorithms for image formation by optical augmented reality systems containing diffraction gratings, including two-dimensional ones, are proposed. Based on these algorithms, virtual prototyping of several augmented reality systems was conducted. Design features, advantages, and disadvantages of these systems were identified. Recommendations for the design and optimization of augmented reality systems using a dual diffraction element configuration are provided.