Innovations in photonics technology have the potential to revolutionize both the inside and the outside of the automobile, making driving, simpler, safer, and more economical. Some of the most interesting applications areas are: lighting, communications, night vision, display, entertainment, and controls. However, the commercialization of these technologies will depend on a number of factors: cost, proven improvements in safety, economy of operation, availability of mass-produced components with high uniformity and reliability, regulations, and standards. The automotive industry recognizes the utility of a roadmap to focus all players, from basic device manufacturing and component integrators, to set manufacturers and ultimately automotive assemblers. In this paper we report on progress on an important component of this roadmap concerning adaptive front-lighting systems (AFS).
Light emitting diodes (LED) are becoming more and more significant in interior and exterior automotive lighting. The long service life, energy and space savings, shock and vibration resistance and new styling potential are the main advantages of using LEDs in automotive applications. Today, most central high mounted stop lamps use LEDs. In rear combination lamps the number of LEDs in amber and red is increasing rapidly. This year, a first rear combination lamp using LEDs for all functionalities including the back-up lamp function was realized. In addition, first signal functions in headlamps using white High Power LEDs were launched onto the market. The long service life characteristic makes LEDs especially predestined for the DRL function combined with the position/parking light. Exterior automotive applications, including requirements and performance will be discussed and an outlook will be given on future scenarios.
The lighting systems of a car provide a variety of challenges from the point of view of illumination science and technology. Engineering work in this field has to deal both with reflector and lens design as well as with opto-mechanical design and sensor technology. It has direct implications on traffic safety and the efficiency in which energy is used. Therefore, these systems are continuously improved and optimized. In this context, adaptive systems that we investigate for automotive applications gain increasing importance. The properties of the light distribution in the vicinity of the cut-off line are of key importance for the safe and efficient operation of automotive headlamps. An alternative approach is proposed to refine the description of these properties in an attempt to make it more quantitative. This description is intended to facilitate intercomparison between different systems and/or to study environmental influences on the cut-off line of a system under investigation. Designing projection systems it is necessary to take a delicate trade-off between efficiency, light-distribution characteristics, mechanical boundary conditions, and legal requirements into account. Considerations and results on optical properties of three-axial reflectors in dependence of layout parameters will be given. They can serve as a guideline for the optical workshop and for free-form optimization.
The "light emitting diode", or LED for short, has already made a name for itself as an alternative luminant for vehicle lighting applications. Lighting functionalities on the interior and on the rear of the vehicle in particular benefit from the advantages of LEDs such as reliability and compactness. Thanks to the rapid increase in power in LEDs, applications in headlamps can now also be represented. This paper focuses on the use of white high-power LEDs in headlamps. As well as explaining the structure of LEDs and how they work, their technical properties in comparison with conventional light sources will also be discussed. In addition, system requirements and LED frontlighting applications will be presented.
The speckle effect disturbs the measurement of spatial correlation functions in solid polymer samples by light scattering. To be able to extract the desired correlations from the measurements, the speckle noise must be suppressed. This is possible by moving the sample during the measurement. In this paper we demonstrate that a sufficient reduction of speckle contrast can be achieved even in samples of restricted dimensions or with a preferential direction.