Retinal Projection Near-Eye Displays with Huygens' Metasurfaces

Most of current commercial near-eye 3D displays use traditional stereoscopic approach to generate the 3D information. A well-known issue for this type of technology is the vergence and accommodation conflict, which leads to visual confusion and fatigue for the viewer. To address this problem, a proof-of-concept solution based on retinal projection technology has been developed to provide accommodation-free virtual images by using a small aperture (360 mu m x 360 mu m) transparent Huygens' metasurface hologram as the display device. The virtual image is generated using a visible laser illuminating a metasurface hologram, which is then directly projected onto the retina using an optical see-through eyepiece. Using this concept, this work experimentally demonstrates a compact and wearable near-eye display of light weight (approximate to 50 g, including spectacle frames, light source, and battery) creating accommodation-free images (clear ranging from 0.5 to 2 m), overlaid with the real world and directly viewed by naked eye. To do so, a new design method is introduced for retinal projection near-eye displays that, inherently, is able to solve the vergence-accommodation conflict using a small aperture Huygens' metasurface hologram.