Headlamp rating system

The paper describes a unique rating method for the quality of headlamp light distributions with respect to homogeneity. Homogeneity is a significant measure of the quality of light distributions for automotive headlamps. As a factor for headlamp design homogeneity has long been neglected. In a unique trial involving 124 test-persons and 21 different sets of headlamps a vast amount data was collected and evaluated. Measurement data for the road illumination, subjective judgment and experimental data was correlated to form a definition of headlamp quality. The findings show, that different areas of the headlamp beam pattern are relevant depending on the overall adaptation level. The results gathered by the study now provide a better basis for headlamp design and may in future lead to a more widely accepted headlamp rating.