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Headlamp performance is typically discussed as a characteristic of the individual headlamp. Parameters like homogeneity, light volume, range and spread of the light pattern are measured and evaluated. However, to assess the headlamp performance relevant for the driving situation, the complete headlamp system as it is mounted, aimed and driven in the car must be the subject of the evaluation. The foundations for the headlamp performance are laid out during the development process of the headlamp. Here the characteristics important for the performance have to be weighed against other aspects, mainly styling and costs. In this paper the system components and other parameter are discussed regarding their impact on the performance of the headlamp.

High intensity discharge lights (HID) are the innovation step that is now beginning to penetrate in all car classes. Investigating drivers, all results show that the benefits are visible to them and positively accepted. The quantification of the improvements has yet been insufficiently examined. In this article some of the aspects will be highlighted.

The introduction of innovative new technologies is related to aspects of safety and to human factors as comfort level and visual appearance. The intelligent headlamp system that is currently being developed allows the combination of the different aspects of driving comfort and safety. The top performing headlamp generations of the future will be the successors of the today’s standard low beam. By using the sensor information available in the car, the light distribution will be adapted to different driving situations and generate an optimized light distribution. Relaxed and safe driving is the goal. Investigations concerning adaptive headlamps are presented. Highway, country road, curves and turning situations are examined by investigating detection distances of standard objects and by rating safety and comfort. Photometric measurements rating glare effects during curve road driving for different headlamp control algorithms are carried out.

The percentage of cars using a projection type headlamp is growing quickly. Lens diameters of 40mm, 60mm, and 70mm are being used in combination with halogen bulbs and gas discharge lamps. The signal image of such projection systems can be improved by increasing the light emitting area with additional optics around the lens. This results in a more comfortable appearance of the headlamps from the viewpoint of oncoming cars. Different optical elements, e.g. Fresnel lenses, prisms, segmented reflectors, are used. A large set of existing projection systems with additional optics around the projection lens is examined and rated by test persons regarding glare, size of the signal image and homogeneity. Also luminance measurements are presented. The correlation between these results are discussed and recommendations for the deign of signal enhancements are given.

Modern adaptive lighting techniques offer the chance to improve the vision of car drivers in front of their car in situations which are not well served by conventional static headlamps. Especially curved roads, intersections and the far zone on straight roads and highways at higher speed need to be illuminated better by the automotive headlamps. This can be achieved by well-designed and tested adaptive light modules. The application of headlamps with adaptive light pattern requires special attention to a new set of questions: Which light pattern should be used to illuminate curves and other areas in the field of vision, how do they fit to the main beam and how should these functions be activated? Technical alternatives to realize the light modules will be discussed and performances will be presented.