Head-up displays (HUDs) can be used under various surround conditions ranging from extremely dark to very bright environments such as daylight. Many head-up displays are designed to enhance visual clarity by adjusting the brightness of the display. However, few studies aim to investigate the impacts of the text-background lightness combination of a head-up display to the visibility as the lighting level of the driving condition changes dramatically. In the study, thirteen observers assess the visual clarity of 20 textbackground lightness combinations on a head-up display with paired comparisons method under a dark and a daylight surround (i.e., 15000 lx) conditions. As a result, the combination of white text with a black background and the black text with a white background presents the significant preference and the best visual clarity under the dark and the daylight surround conditions, respectively.
Hsin-Pou Huang, Minchen Wei, Hung-Chung Li, Li-Chen Ou, "Optimal Text-background Lightness Combination for Enhancing Visual Clarity Using a Head-up Display under Different Surround Conditions" in Proc. IS&T 28th Color and Imaging Conf., 2020, pp 210 - 214, https://doi.org/10.2352/issn.2169-2629.2020.28.33