HEADLAMP DESIGN: THEORY AND PRACTICE.

With the rapidly increasing emphasis placed by vehicle designers on reduction of fuel consumption, engineers at Bosch say that two requirements have emerged with a major impact on headlamp design. The first is a need to save weight. Secondly, aerodynamic efficiency considerations call for better streamlining. To merge with the body profile and to keep aerodynamic drag as low as possible, the height of the lamp must be reduced. Other demands for the future will include the addition of some reliable means of keeping the lenses clean, and for adjustment - either manual or automatic - of the beam elevation to compensate for changes in load distribution in the vehicle as suspensions become softer. The article shows the effect on beam ranges of different types of lamp configurations, and for deep and shallow reflectors. The use of plastics for the lens could reduce headlamp weight up to 21%; possible problems with the use of plastics are discussed.