Colour-Difference Assessment for Driving Headlight Simulation

Abstract

In high quality driving simulation applications, such as headlight simulation, colorimetric validity is essential. In virtual testing of headlight systems, it is important that the WYSIWYG (What You See Is What You Get) paradigm is respected for product quality headlight assessment. Indeed, if a slightly reddish orange colour is displayed instead of the typical orange of halogen lighting, the effect for driver comfort or traffic safety can be critical. The lighting specialist should accept a headlight which doesn't have the right colour. Previous studies have shown that there is a significant colour difference between virtual and real environments. Nevertheless, in virtual headlight testing the rendered colour fidelity has to fit industrial assessment. This study therefore deals with the colour-difference perceptibility that is the ability of an observer to detect a difference between two colours and, more precisely, on the acceptability of the perceived difference. We propose in this paper a psychophysical function for colour difference acceptability which fits well with the measured data. The colour acceptability function was implemented in a driving simulator for high validity headlight assessment. Driver acceptability experimentation was carried out using Renault's headlight driving simulation equipped with a fullcab and a 210° cylindrical display screen.