| Title |
Examination of the Limitation of Daylight Glare Index for Evaluating Discomfort Glare from Windows |
| Authors |
Kim Won-Woo ; Shin In-Joong |
| Keywords |
discomfort glare ; luminance ; windows ; background luminan |
| Abstract |
The limitation of DGI is examined by the subjective experiment. Discomfort glare from a real daylight window is appraised. The window is divided into 6 parts. Discomfort glare from each part of the window and from the whole window is evaluated by thirty-two subjects. The degree of discomfort glare is an increasing linear function of luminance of each part, but the average luminance of the whole window is not related to the degree of discomfort glare. It is concluded that the average luminance of the entire window is unlikely to be a factor in the genesis of discomfort glare. In the DGI formula, the source luminance is calculated by the average luminance of the entire window, so that DGI method can not assess accurately discomfort glare from windows. |