Curved waveguide combiner for HUD/AR

Abstract

Most of waveguide implementation for HUD or augmented reality combiner are flat pieces of glass because the image propagation does not suffer from any aberration when traveling along their length. However, this type of combiner does integrate seamlessly in front of the viewer eyes and a curved optics would be much more appealing. Using holographic optical elements, we demonstrated that it is possible to correct the aberrations induced by the curved surfaces of the waveguide, and display a aberration-free image to the viewer. This correction applies for different waveguide geometries (1D or 2D curvature) as well as different pupil expansions (1D or 2D expansion). A Zemax model is presented along a curved waveguide demonstrator.