The assessment of a new cockpit colour concept using the Occlusion Method

The first vehicle cockpit colour concepts were developed based on the light used in submarine vehicles. This was primarily because operators were not typically exposed to external light sources and operated under the scotopic visual range. Red lighting was used as it does not disrupt dark adaptation. Based on this, many automobile companies developed their night time concepts in red. However, when driving in an urban setting at night or twilight, the lighting level is described as mesopic. Because of this, a white cockpit colour concept becomes a viable option. In this study, two colour concepts were compared under mesopic vision conditions. The main objective was to assess whether both concepts yielded similar results in terms of interpretability, readability, and differentiability of information. For the experiment, 30 participants performed an occlusion task. A cockpit display with a speedometer in either colour appeared. The cockpit was presented for different duration times to simulate short glances at the speedometer. Statistical tests were performed to examine global response accuracy and mean accuracy for particular presentation times. No significant differences were found. In sum, this paper confirms that a white concept shows no disadvantages relative to a red concept under mesopic lighting conditions.