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Good lighting is crucial for safe driving at night. Unfortunately, many parameters are contributing to the final result of the individual tolerances of car body, dynamics and headlamp: the resulting aim. The paper will analyze individual tolerance contributors from car body parameters like load, tire pressure, suspension as well as temperature parameters of chassis and plastic parts. The investigation shows that the headlight aim can fluctuate in a worst case scenario more than ±0.3°.

The paper will describe actual investigations on safety improvements by new lighting functions. Especially the new chance of projections on the road surface either by simple reflector technology or by modern signature and pattern projection will be investigated. Different prototype patterns will be checked by a set of new parameters, e.g. reaction time to signals, clear understanding, minimum and optimum visual contrasts. The results show that high contrasts and dynamic effects are most effective.

The conventional measurements to describe the photometric quality of headlamps usually only comprise the luminous flux and the illuminance (resp. the luminous intensity) in several measuring points given by Type Approval Legislation. Practically, these photometric measurements do not describe the visual impression of a headlamp light distribution sufficiently, neither in lab nor in real street geometry. With the clear outer lens headlamps introduced recently, filament images are projected directly onto the screens or streets, thus giving new impulses to research. Starting from the established photometric practice, other types of measurements and physiological fundamentals will be discussed. The basic tools to make physical measurement and physiological impression comparable, e.g. in terms of homogeneity, are shown.

1 In 2008 the first full LED (LED = Light Emitting Diode) headlamp will arrive to the worlds markets, providing all lighting functions with semiconductor based light emitting devices, LED. The first Full LED headlamp differs in style and technology from other headlamps. Target was to find a face that fulfils the demands of the stylists and also gives the possibility to be assembled, to fulfill customer specs and legal requirements. Fulfilling this, the development showed various intermediate steps. As LED is still a evolving technology, mature and fixed technical solutions were and are not always existing. So technical solutions had to be developed under the constraints of new technology and regarding the existing mechanical and electrical environment in the car.

The first All LED headlamps have arrived in the market, providing all lighting functions with semiconductor based light emitting devices, LED. That was a huge step: the first fully electronic headlamp of the world. Aside from photometry and lifetime advantages, LED offers opportunities in saving CO2-Emissions and thus reducing Energy consumption. 2008 was for the first time a headlamp available where all lighting functions including low and high beam were completely realized with Light Emitting Diodes (LED).

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.

After about one decade HID headlamps are available on all major market areas. Since the design and manufacturing possibilities have changed in that period, the current light performance will be reviewed in the paper. The market penetration in the three major markets shows obvious differences. The penetration related to car platforms and classes will be discussed. It will be shown that HID headlamps have different penetration level in US, Japan and Europe. Additionally, the future styling development will be evaluated by the technical possiblities given today using reflector/projector type and additional illuminated areas. A future styling trend will be estimated for the three different markets. The future application of HID headlamps in adaptive lighting systems will be analyzed.

The development of headlamps was found to experience a dynamic process. For more than 50 years the tungsten double filament bulbs (Bilux) had been dominating the lighting technology, followed in the seventies by the H4 bulb. Since the middle of the eighties the modern filament bulbs as H7 (now H9, H11) have been available. The Xenon gas discharge (or HID-) technology reached the automotive market in the nineties. Now the development is heading towards the new technology step. Adaptive „intelligent“ headlamps will bring the headlamp from its isolation in the front module back into the world of electronics and car networking systems.

Headlamp performance has changed in the last 20 years significantly. Sealed beam lamps were replaced by VHAD, VOR and VOL types, but still the optical input in terms of tungsten filament based luminous flux remained more stable. With Xenon discharge lamps and now LED the performance of a headlamp may vary strongly and thus the optical performance. Various rating systems have been developed to assess the quality of lamps and light distribution, some based on laboratory based data, some based on static or dynamic street test drives with online measurements and assessments. Basic interest is to understand the performance of the light for a real driver. This article will discuss the influence parameters on achieving a repeatable and precise rating as well as the outer influence that creates glare and varying seeing distance. Mostly mechanical headlamp and car conditioning will influence the result as well as human factors like aiming precision and aiming tolerances.

After the first series applications with LED in headlamp signal functions are on the road or close to production release, the next continuous steps are considered in the paper. Side markers and Position lamps, Daytime Running lamps and Turn Indicators are considered to be in a technology ready status. Despite the fact that fog lamps have low luminous flux and photometrical requirements, the challenges due to glare avoidance and aimability via cut off line have reached a new level. Technical concepts and performance will be discussed with measurement data evaluation. Due to the fact that different LED suppliers are on the market with different optical and mechanical solutions, a matrix evaluation will be driven for photometrical and efficiency potential. Another significant impact will be the styling influence of the exit apertures. Studies for LED fog lamps will be presented. Several LED sources require a dedicated electronic driving concept.

In this paper, the human intra- and interpersonal adjustment accuracy (or aiming) of headlamp cutoff lines with different methods are examined. Intrapersonal aiming accuracy is the repeatability of a single person, while interpersonal aiming accuracy describes the differences between different people. For this purpose, a study is developed, implemented and evaluated. In one experiment, the subjects set up three different headlamps using three different methods according to the ECE regulation. In addition, the three adjustment methods used are compared with each other and evaluated in terms of the variation resulting aim. The most common aiming method, the visual adjustment of the cutoff line, such as the 10-meter wall method or analog headlamp aiming devices shows the highest variations. It is shown that digital headlamp aiming devices generally also have a lower dispersion variance, while still being better than all other adjustment methods.

Two research fields are presented in this paper covering new lighting functions. In the first part, a study is presented that evaluates distraction by light animations. 41 test subjects were involved, and a situation was constructed with several traffic participants and an animated-light vehicle parked so as to be conspicuously within the test subjects’ view. 91% of the test subjects stated they felt little or no distraction or impairment from the light display on the parked car. 29% noticed something conspicuous about the test vehicle. 22% indicated they had noticed the car’s lights flashing as its central locking system was operating. Only 7%—three of the 41 participants—noticed the animations in addition to their traffic monitoring. Of these, two said they didn’t feel disturbed at all by the animations while the third found it only very slightly distracting. Nobody said the distraction or impairment was “neutral”, “little bit” or “strong”.

The characteristics of the semiconductor based Light Emitting Diodes (LEDs) is completely different to the characteristics of traditional light source used in automotive exterior front lighting systems. The characteristics include not only optical items, but also electrical, mechanical and temperature issues. These characteristics make new approaches in the field of automotive headlamp development necessary. Due to the designer's wishes, the LEDs must be mounted on a 3-dimensional surface with small tolerances to the associated optics. High power LEDs create a lot of heat, so that they have to be assembled with a cooling device. The generated heat should be used for defogging and deicing of the outer lens of the headlamp. Electrical drivers are needed to keep the current through the LED constant. All new technical challenges will lead to more stylistic freedom

In addition to the low and high beam functions, some modern headlamps also have the option of switching on only section of the high beam. The so-called adaptive high beam is intended to increase the detection distance of objects and through that drastically improve the road safety. At the same time, this function does not increase the glare for oncoming or preceding traffic. This is enabled through switching the different segments of the high beam on or off, depending on which and where other road users are recognized by the front camera. This massively increases the use of the high beam, thus increasing road safety. In this study, the increase in the detection distance of objects on a straight line is statically investigated with a test person study. Furthermore, the glare of each of these three light functions is observed.

When designing new vehicles, the legal requirements of the countries in which the vehicles are homologated must be observed and implemented. The manufacturers try to consider the legal framework of the UN-ECE (United Nations Economic Commission for Europe), CCC (China Compulsory Certification) and FMVSS (Federal Motor Vehicle Safety Standard) 108 in the same vehicle to keep the variance low. For the appearance of the vehicle, the position of the light modules in the front of the vehicle is important. In addition to the surface requirements of lighting functions, the positions of the low beam (LB), high beam (HB) and the position of daytime running lights (DRL) are also regulated. When it comes to these mounting positions, the legislation between the US and the EU differs quite significantly.

This paper will present a new method to describe headlamp light distributions by taking into account visible performance, measurable lighting parameters and physiological comfort aspects. Up to now, headlamp light distributions have been evaluated by looking to photometric measurements, which are displayed as isolux or isocandela values. Based on investigations intended to examine the driver's basic requirements for a good light distribution, the resulting measurement tools are split into two sections to describe the performance: Safety and Comfort. For both sections, the tools are described and demonstrated with two light distributions that show different behaviour. The Safety evaluation tools are defined and presented. For the Comfort of driving, the light distribution generated on the street concerning luminance, contrast sensitivity and homogeneity are further parameters. A new possibility of defining a single quality parameter for the homogeneity is given.

This paper will describe the procedures that will enhance the possibilities of qualitative evaluation of headlamp light distributions. A basis will be the description of a light distribution coming only from reflector geometries, i.e. headlamps with clear outer lens design. Further steps of evaluation, as visualization and homogeneity analysis become more and more important for a headlamp evaluation. The recently developed tools can support both the headlamp manufacturer and the car manufacturer in finding a common understanding in headlamp performance of a projected car at a very early stage of development.

The current development of automotive lighting strives towards more and more lighting installations on vehicles. Additionally, to that, manufacturers start animating these lighting installations as coming home or leaving home greetings from the car to the driver. In a previous paper we have shown, that these additional animations are in fact not distracting to other road users and when used correctly, e.g. in a sequential turn indicator, can be beneficial to the overall traffic safety. This study then aims to investigate the potential influence of illuminated logos on road safety. European lawmakers forbid the use of illuminated advertisements on vehicles to minimize the danger of distraction for other road users and thereby negatively influencing traffic safety. As of now, active illumination of the manufacturer’s logo is considered an advertisement.

Digitalization in Industry and Society is progressing quickly. Up to now, just 5 static and standard lighting applications have been dominating in the U.S. (Low/High Beam, Daytime Running Lamp Turn Indicator & Position Lamp). The global interest in standardization of light driven messages from autonomous vehicles to other traffic participants has opened new research needs and research findings. In Europe, GTB has established a working group dedicated to this topic. The article will discuss the possible contribution of signalling and lighting functions to Digitalization and Autonomous driving by explaining the first elements of functional definition and research results.