Visual Fatigue Reduced by Anti-Refelective-Glace Filtering for Liquid Crystal Displays

Liquid cryistal displays (LCDs) have been widely used in visual display unit work. These LCDs maintain superior visibilituy nder a higher diffuse surface reflectance compared with cathode-ray tube displays. Specular (mirror-like) reflection on LCDs, however, can cause disturbed visibility and the resultant visual fatigue. The present experiment was designed to investigate whether visual fatigue consequent to the specular reflection on LCDs could be reduced by anti-reflective-glare filetering. Visual fatigue was compared between three experimental conditions, one with specular reflection and two with the use of different anti-reflective-glare filters (multicoating type and matprocessing type), under a within-subject experimental design. Each of twenty subjects performed a visuals earch task consisting of three sessions of 25 min each followed by a rest period of 25 min. Grating acuity, dark-focus accommodation, and replies to a visual fatigue questionnaire were studied at the beginning of the experiment, after each session and after the rest period. The results of the visual fatigue questionnaire showed no significant differences between the three experimental conditions. However, the use of anti-reflective-glare filtering of multicoating type induced significantly better visual search performance and visual acuity. The use of mat-processing type filtering showed less influence on dark-focus accommodation. These results suggest that the prevention of specular reflection on LCDs may lead to the possibility of reduced visual fatigue