The photometric requirements of today’s headlamps do not relate to the headlights as built into the vehicle, but to the individual headlamp before its instailation. The aim of this survey is to demonstrate the relation between technical requirements of individual headlamps and the actual situation on the road. For that purpose headlamps were measured: on the one hand those of known vehicles (reference vehicles) with correctly adjusted and cleaned headlamps; on the other hand headlamps in everyday traffic, i. e. possibly incorrectly adjusted and soiled.
It could be shown that the glare of iiluminance of the gas discharging headlamps in the measuring point of the human eyes of an on-coming car is lower than of normal traffic vehicles.