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LED headlamps enable unique styling solutions and a range of beam functionalities. After the first highly sophisticated designs and solutions, the range is extended to the mid and lower class with more essential designs and basic functionality. The headlamp architecture has to reflect the various levels of complexity. Engineers in the industry are currently trying to identify the building blocks that allow supporting the various levels in an economical way by reusing components and construction principles. The LED light source is an important element that interacts strongly with the system. As a light source manufacturer we are faced with the requests to come forward with sources providing superior styling flexibility, ease of use and system cost reduction. In this paper, we will show options, how this can be supported.

Today, LED automotive exterior lighting is already widely used on high end and upper middle class vehicles. We see already first examples of application as the standard lighting solution even in the mid class segment. A compact design and the feasibility of car life sealed solution is a strong argument to use LEDs for CHMSLs. Long lifetime and new styling opportunities speak for LEDS in front or rear position lights as well as in daytime running lamps;. Mainstream penetration of LED lighting solutions will first happen for functions where the benefits of LEDs have the highest positive impact and where this value can be realized in the most cost-effective way. During the different phases of the introduction of LEDs different requirements dominate the decision process. Providing unique styling opportunity and showing advanced technical functionality is leading for the early adopters.

This report investigates the use of single and multi-layer coatings on replaceable headlamp bulbs and how such coatings can affect the performance of bulbs in terms of light scattering, which can contribute to glare, and spectral separation in headlamps. Tests were developed to investigate the effects of absorptive and interference (multi-layer) coatings on bulbs, and on bulbs in headlamp systems. These tests provide validation for a proposed bulb color separation test, which establishes limits for spectral separation within the boundaries of SAE J578 white color requirements. The bulb color separation test provides a definitive selection criterion to identify bulbs that cause excessive light scatter (glare) and/or spectral separation in an optical system.

The purpose of night vision systems is to provide drivers during night and adverse weather with visual information beyond the range of their headlamps and beyond the glare of an oncoming vehicle's headlamp. Thus the driver has more time to react in case of unexpected and dangerous situations. Basically, two different concepts can be followed up. Passive night vision systems visualize the thermal radiation emitted by the objects themselves [1] while active night vision systems image near-infrared radiation which is reflected by the objects in the scene. Unlike passive systems, active night vision systems need powerful near-infrared light sources and cameras which are considered especially with respect to automotive requirements. Halogen light sources are the most promising candidates because about 25 percent of the total radiated power of a 60 W lamp lies in the near-infrared wavelength range from 800nm to 1100nm.

DLS offers exciting new possibilities for design and performance of headlamps. The powerful HID source technology is ideally suited to serve as light source for such a DLS, combining the benefits of both technologies to a completely new headlighting concept. The intention of the paper is to give an impression of the efficiency and performance of the system and to point out the prerequisites and parameters for the light source that influence the performance. Starting from the performance of present HID headlamps and based on sound considerations of losses of the various components of a DLS, the beam requirements are traced back to the necessary properties of a HID light source and bulb driver dedicated for DLS. From both calculations and measurements an estimation of the overall performance for the system is derived, with focus on incoupling efficiency.

Many traffic accidents - not only during nighttime - are caused by late or failed recognition of moving vehicles. Daytime Running Lamps (DRL) lead to better conspicuity and thus helps to reduce traffic accidents. This has recently been confirmed in a study by Koornstra, Bijleveld and Hagenzieker [1]. Nevertheless, the extra power consumption and its environmental impact is often used as argument against the general introduction of mandatory driving with lights. We have investigated possibilities of how to realize DRL with low power consumption. Several reflector concepts have been analyzed. Existing bulbs have been considered as well as some new developments.