Bifunction HID Headlamp Systems - Reflection and Projection Type

For headlamps whose low beam function is equipped with High Intensity Discharge (HID) technology, a high beam counterpart of equal lighting performance is presented which fits in the constructional space available in modern cars. The new Bifunction HID system allows the use of HID technology for both low and high beam in the same reflector, utilizing the same bulb and electronic control unit.

Bifunction HID technology on the basis of reflection as well as projection type systems will be presented in this paper. An overview of the regulation guidelines for world wide application of this new technology is given. The main aspects of the switching mechanisms and their effects on the light distributions are discussed and compared.