The purpose of this study was to propose a formula of the position index for evaluation of the glare source in the whole visual field. The glare sensation was measured to create the formula in binocular and monocular vision. The results showed that there is not a big difference in the level of discomfort glare sensation between the left and right eyes while the lower visual field is more sensitive to the discomfort glare than the upper visual field. Based on the borderline between comfort and discomfort luminance distribution in the whole visual field obtained through a series of experiments, position index was created, which was then turned into a formula. When predicting or evaluating the discomfort glare generated from the indoor or outdoor lighting with a computer, this formula would be of great help in easily identifying a position index. The findings of this research would provide important basic data for the evaluation of discomfort glare.
Relation between luminance distribution of surround visual field and contrast threshold
