High-resolution vehicle headlamps are the technological way to intelligently illuminate the traffic area to increase safety and comfort. For the technical realization of these headlamps, different technologies come into question, which are the subject of intensive research at universities and among the manufacturers. We present an overview of the possible technologies and analyze their potential for use in high-resolution headlamps. Furthermore, we explain how the design of the optical system for the different technologies can be made. Another part of this paper is the comparison of published prototypes of high-resolution headlamps and the compilation of key properties.

With regard to autonomous driving, on-road projections cannot only be used for communication with the driver but also with other road users. Our study aims to investigate the distraction potential for other road users when on-road projections (e.g., for driver assistance) are used to communicate with the driver of the projecting vehicle. We perform this investigation in a blind study with 38 test persons who are overtaken six times on a constant motorway section by the projection vehicle. The distraction potential is examined with an eye-tracking system, which detects the direction of the subjects’ gaze. In addition, the subjects’ physiological perception of the headlight projection is recorded with a questionnaire afterward. Several test subjects looked at the projection for less than one second, which is well below the critical threshold for the distraction of 1.6 s. In the interviews, on the other hand, only one of the 38 test persons stated that a projection on the road was recognized. For the examined scenario, it is therefore deduced that on-road projections with the selected symbol shape and brightness do not lead to critical distraction.

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High-resolution light distributions are lately in demand for vehicle headlamp systems as an innovative lighting approach. This lighting approach can realize functionalities, such as precise glare avoidance and on-road projection, which are useful for improving traffic comfort and safety. For achieving the required high-resolution light distribution, area-based projection technologies, such as DMD, LCD, and LCoS, are considered to be integrated into such headlamps. These projection devices demand rectangular illumination areas with specific light distributions to fulfill the requirements for illumination efficiency and performance in headlamp systems. Lenslet arrays, based on the principle of Köhler illumination, can effectively homogenize the light and shape it into rectangular shapes simultaneously. Such components are widely used in projection applications. However, they also show functional potentialities to be applied in high-resolution headlamps. This paper explains the design principles and methods of lenslet arrays for beam pre-shaping in headlamp systems. It validates the homogenization using a self-designed and manufactured lenslet array in a demonstrator in the first place. Afterward, this paper introduces two new methods for the centralized beam shaping required by some headlamps. These methods are validated by optical simulations.

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Adaptive headlamps with innovative lighting functionalities can increase traffic safety. Subtractive light modulators such as Digital-Micromirror-Devices (DMD), liquid crystal displays (LCD) or liquid crystal on silicon devices (LCoS) are considered to be used as an implementation with a high resolution. In order to realize the regulated light distribution as well as to improve the optical efficiency and on-road projection quality of such headlamp systems, an inhomogeneous illumination on the modulator and whereafter low distortion projection optics are considered. In this paper we present simulation results of an optical concept of inhomogeneous illumination for headlamps.

The integration of optical technologies into once purely mechatronic systems enables innovative functions, but simultaneously increases the complexity of previous mechatronic system development. Therefore, a process has been elaborated to develop these so-called optomechatronic systems by Knöchelmann at the Institute of Product Development at Leibniz University Hanover, which is based on the V-Model of VDI 2206 and can be applied to various fields of application. For a target-oriented development in a specific product context and for systems with competing main requirements, detailing and adapting the process is recommended. High-resolution lighting systems are one of them, where requirements for high optical efficiency and image quality lead to a conflict of objectives. Focusing on the optics domain, Ley elaborated methods for the preliminary and detailed design of high-resolution lighting systems to address the aforementioned conflict of objectives. This contribution focuses on the integration of Ley’s design methods into Knöchelmann’s process model within the phases of system design and domain-specific design, allowing us to analyze the impact of the system design on the fulfillment of main requirements to achieve an optimal solution of the conflict of objectives. To illustrate this, the integrated process model is described using an example from automotive lighting technology.

Road safety enhancement: an investigation on the visibility of on-road image projections using DMD-based pixel light systems,"