Search Results

In order to further improve motor vehicle lighting, headlamps with instead of the current incandescent. lamps are being developed at Robert Bosch GmbH, Stuttgart, under the designation LITRONIC (Light Electronics). Compared to headlamps with conventional bulbs, the LITRONIC headlamp achieves a greater luminous efficacy, thus contributing to a considerable improvement in safety on the roads. Function, construction and initial system experiences from a testing of samples of the new headlamp system will be described.

The built-in space available for a headlamp in motor vehicles has been steadily reduced by vehicle manufacturers over the last few years. In order to continue to provide the driver with the necessary safety equipment, new headlamp designs with improved efficiency are necessary. One such new design, the reflector with variable focus (VF Reflector), is presented in this paper. The mathematical concept of VF reflectors is explained and the advantages in lighting technique over conventional reflector systems are illustrated by means of concrete examples.

This report gives an overview of the current status of developments intended to improve the low beam of motor vehicle headlamp systems by use of segmented reflectors. In addition to advantages in terms of lighting technique (gain in luminous flux, increasing safety for the driver as a result of improved lateral illumination level and foreground brightness), the segmented reflector also accommodates the stylistic wishes of the automobile manufacturers (smaller overall height, larger angle of inclination of the lens), and thus represents a genuine alternative to the Polyellipsoid headlamp (PES) for the future. The advantages will be explained and quantified using concrete examples.

In the last years, motor vehicle lighting systems were required to be more efficient, to have shorter development times and to be of higher quality. One important tool used in complying with these demands is the computer calculation of the optical characteristics of the complete headlamp system. A newly developed software package is presented in this paper which permits the configuration of a headlamp in its basic optical components and the quantitative calculation of its light distribution, luminous flux and other optical quantities. It is now possible for the first time, to assess a headlamp's total light pattern in advance, without hardware (e.g. model headlamps etc.) being required. The simulation results show a high degree of concurrence between the computed and the measured light distributions. This will be demonstrated in detail using concrete examples.

A new automotive headlamp system using a projection lens has been developed in Europe and given the designation PES ( Poly- Ellipsoid- System). Improvements over the conventional ECE headlamp are possible both in the design of the front-end of the vehicle and, most importantly, in lighting technique. For complete accommodation of the needs that arise while driving, basic conditions must be taken into consideration in the development of the PES headlamp. The lighting technique results attainable are demonstrated by presentation of comprehensive measurements and by a series of photographs. It is shown that the PES-headlamp is superior to the conventional H4-headlamp in all important aspects. Thus, the ranges are greater in all directions, and driving through curves is improved considerably. The advantages are made permanent by listing in a general outline for a new measurement specification.