Full-color AR 3D head-up display with extended field of view based on a waveguide with pupil replication

Abstract

Augmented reality (AR) devices such as head-up displays (HUDs) burst into our lives, especially in the automotive industry. AR HUDs should display 3D images within a wide field of view (FoV) to bring in full immersion. However, HUDs with a wide FoV built on conventional mirror-based architecture occupy significant dashboard space and cause overheating of the display. These factors limit the integration of such wide FoV HUDs into vehicles. Instead, we propose AR HUD with a wide FoV based on a thin waveguide. A key feature of our display is the ability to deliver 3D virtual images while maintaining a small system volume. Our approach to combining both benefits is based on integrating novel units into a pupil-replication waveguide. First, a multi-view picture generation unit (MV-PGU) creates autostereoscopic 3D content within the same FoV. Then, the content is transmitted through the waveguide in a conventional pupil replication manner. Finally, a thin optical module, which we call the multi-view eyebox formation unit (MV-EFU), separates the images for the corresponding views based on the distinctive parameters. Moreover, we investigate the possibility to extend FoV by choosing the optimal parameters of the invented units. We validate our concept by raytracing simulation of a developed full-color display with an FoV of 20° × 7°. Additionally, we assemble a prototype with reduced display specifications to verify the approach experimentally.