Abstract
Two experiments were carried out to investigate the required luminance and luminance contrast for transmissive liquid crystal displays. In experiment 1, 30 subjects rated 156 luminance and luminance contrast combinations displayed on a transmissive thin-film-transistor liquid crystal display, under three kinds of ambient illuminance conditions : 70, 200 and 500 lx. The results indicate that under a 500-lx illuminance condition, the combination of a display luminance approximately 100cd/m2 and a contrast ratio higher than 10 is the most preferable condition. In experiment 2, 20 subjects were asked to adjust the display luminance of the transmissive thin-film-transistor liquid crystal display as they most preferred every two minutes during a visual search task, under two ambient illuminance conditions : 70 and 500 lx. The results indicate that the preferable display luminance is affected by adaptation luminance for the display screen. The range of preferable display luminance between subjects is relatively wide. These results suggest that a wider adjustable range of the display luminance is required in order to adapt a preferable display luminance for each user.
