The Effects of Headlight Glare on Vehicle Detection at Dusk and Dawn

Teii experienced drivers perfanlied a series of closed-course tests to deteniiirie whether a target vehicle, located between other oiiconting vehicles iii a siiigle-lane convoy, corild be detected wider various levels of ariibieiit ill~intitiatioii, with its loiv beam lieadlights oii aiid offt aiid rvitli different headlight cotifigiiratiom OH the srirroriridiiig veliicles. Levels of atti-bieiit illiiiiiiiiatioii varied from approximately 0.2 to 2100 Ix dririiig the experiment. Resiilts iridicated that loiv beam headlights OH sitrroiittding vehicles masked the icnlit target vehicle. The degree of masking depended on the level of veiliiig Iiitninaiice eiiritted by the srirroriiidiiig vehicles arid on the level of ambient illtiininatioii. It ivas also found that the target vehicle ivas more visible tirider all experiniental conditions ivlieii its headlights were 011 tliari ivlieii they were oft: Resrilts are discussed in relatioil 10 subject arid rveailier variations and in tenils of curretit lights-on l a w