Implications of Adaptive High Beam Headlighting Systems for Discomfort and Disability Glare 2009-01-0549
The Laboratory of Lighting Technology at the Technische Universität Darmstadt has conducted experiments to verify whether the prevalently reported different glare strains of the three light sources in automotive lighting, namely tungsten halogen lamps, high intensity discharge lamps and LEDs, can be verified in real traffic geometry.
Furthermore, these light sources will be used for new adaptive driving beam functions. These systems will alter the conventional cut-off lines or simply switch off sectors where other road users have been detected. It is therefore probable that these other road users will experience more glare illuminance than they would, if the oncoming car would be equipped with a well aimed classical passing beam.
The tests take place on a former air field now used as the university’s testing site. Apart from the glare sources no other visual disturbances are present. The geometry of the test setup is chosen to represent a real traffic situation.
The overall results show no significant differences with regard to disability glare, although a minority of test subjects showed a significantly higher sensitivity to tungsten halogen lamps than to the other light sources. No subjects showed higher sensitivity to either of the other two illuminants.
The tests suggest no need for new regulative action featuring dedicated glare prevention measures for LED incorporating head lights. Instead, the existing regulations ECE R-98  could be enhanced to include LEDs as permissible light sources as well. ECE R-123 is already formulated as such that no specific light source is mandatory.