Effects of the characteristics of stimulus and work condition on visual performance and visual fatigue of VDT work

Abstract

This study examined the effects of color combination, typeface, ambient illumination, and stimulus duration on visual performance and visual fatigue of subjects working at a visual display terminal (VDT). Typeface, ambient illumination, and stimulus duration, each with two levels, were between-subject factors, while color combination, with 5 levels, was within-subject factor. Correct percentage of performance, critical fusion frequency (CFF), near point of convergence (NPC), subjective visual fatigue, and preference ranking of color combinations of 40 subjects, five in each experiment treatment, were collected and analyzed. Results showed that color combination and ambient illumination had no significant effects on visual performance. The results might arise from some characteristics of the experiment. As expected, longer stimulus duration resulted in better performance. However, interactions involving stimulus duration were not significant. Typeface significantly affected performance. Aesthetically pleasing but more cluttered characters might be detrimental to performance. Subjects also showed differential preference for color combinations. Red-on-green was ranked inferior to color combinations generally used in computer software.