55‐3: Holographic Grating to Improve the Efficiency of Windshield HUD

Abstract

A Windshield Head-Up Display (WHUD) using an embedded optical thin film to improve the system efficiency is presented. Most of today's WHUDs, including the most advanced devices, use the windshield as a simple half-mirror, so that the main part of the optical flow is not reflected toward the eye-box. Even with recent work, aiming to increase the optical efficiency of the Picture Generating Unit, or the set of mirrors or light-guides, reflectance efficiency is not greater than 20%. Experiments performed on the first prototype using Transparent Holographic Optical Components show an optical efficiency of 85%. This result will open the way for a more compact green product device (with a huge reduction in power consumption). 55-3 / P. Coni SID 2018 DIGEST • 729ISSN 0097-996X/18/4702-0729-$1.00 © 2018 SID 55-3 / P. Coni

56‐1: A Multiplane Holographic HUD Using Light Selectivity of Bragg Grating

“…Using the angular selectivity is one solution to get a multiplane HUD, but it needs one PGU for each plane, and we can't imagine a such bulky device in a car without a strong compromise in term of viewing angle or eye box [7].…”