Research on surface relief grating design technology for augmented reality display

Augmented reality technology is a technique that combines virtual information with the real world, providing an enhanced perception and interactive experience by overlaying virtual content in the user's field of view. In augmented reality technology, surface relief gratings are widely used in optical projection systems to achieve precise positioning and accurate projection of virtual images. In this study, we first designed surface relief gratings in three regions - coupling, turning, and output based on the rigorous coupled-wave analysis. Then, by gradually optimizing parameters such as duty cycle, tilt angle, and depth of the gratings in each region. We ultimately achieved overall structural optimization with respect to uniformity and optical efficiency. This research provides valuable guidance for further exploration of micro/nano structures in the field of augmented reality.