The Influence of Vehicle Beam Patterns on Safety and Acceptance 2004-01-1766

What characterises a good vehicle headlamp? Which headlamp features contribute to a larger visual range? A study has been carried out to investigate the influence of a wide range of different technical lighting parameters on the visual range of headlamps. The method of image-resolved luminance measurement was used for this purpose. A variance-analytical approach was chosen as the investigation design. In place of standard targets made of cardboard, realistic looking objects such as differently dressed display dummies and stuffed animals were used. The investigation revealed significant differences in the distances at which the objects were perceived depending on the headlamps used. The best predictor for forecasting the visual range was a coefficient derived from the luminance images. Of major importance for the perception of visual objects – even at a relatively close range – is light flux, which is directed onto the road beyond the cut-off. In addition, the acceptance of headlamp beam patterns was evaluated by test subjects. These test subjects revealed completely different preferences. There was no statistical correlation established between the visual range of headlamps and the acceptance of their respective beam pattern.