REUTLINGEN, GERMANY--German carmaker Audi (Ingolstadt, Bavaria) is implementing what it claims is the world’s first all-LED headlamp for an automobile in its latest luxury sports car, the R8. Comprising a housing, LED array, and circuit board, the lamp utilizes LEDs for all front-lighting functions, including low beam, high beam, turn signal, daytime running light and position light. Automotive Lighting, a wholly owned subsidiary of Magneti Marelli (Milan, Italy), is supplying the headlamps to Audi, which will offer the LED assembly as an option for the R8 next year.
According to Audi, more than 20 innovations have been integrated into each headlamp. The assembly comprises two LED arrays with four active elements each, embedded in a free-form reflector. Three additional LED arrays with two LED chips each are located behind an optical lens; their task is controlling the bright/dark boundary and the range of the headlights. For the high-beam headlight, a four-LED array is located adjacent to the low-beam arrays. Near the lower edge of the assembly, a row of 24 LEDs forms the daytime running light. Further elements of the lighting assembly are printed circuit boards carrying the LED chips and a heat sink. A blower keeps the LEDs cool and de-ices the unit when necessary.
Using LEDs for the headlamps offers several key advantages, according to Audi, including low energy consumption (50 W with dipped headlamps and 6 W with daytime running lights). Another advantage is the color temperature, which is approximately 6000 Kelvin (nearly equal to the quality of daylight). The human eye perceives the road and the edge of the lane at night in their natural colors and differentiates contrasts considerably better. In addition, the average lifetime of the light-emitting diodes in all functions is longer than that of other headlamp.
While the new technology has not yet been approved for standard use, the European Commission granted Audi special permission for the deployment of pure LED lights in production cars. An EU regulation regarding the use of this technology for vehicles in general is expected sometime next year.