This paper presents results of field studies conducted to predict headlamp beam usage and drivers' dimming request responses as a function of glare headlamp photometry, road background brightness and topography. The results show that the driver's dimming request behavior is dependent upon the level of discomfort glare experienced by the driver when the approaching vehicle first appears in his view and the potential glare exposure, i.e., the time-distance during with the glare could be experienced by the driver.
Abstract