Hella has developed a full-LED headlamp for the Cadillac Escalade Platinum – start of series production will be in summer 2008
Lippstadt / Detroit, 19th November 2007.
Lighting and electronics specialist Hella has developed a full-LED headlamp for the Cadillac Escalade Platinum. Thus it will be the first sports utility vehicle (SUV) in the world to be equipped with this forward-looking lighting technology. With a colour temperature of around 5,500 Kelvin, the light colour of the white LEDs is considerably closer to daylight (approx. 6,000 Kelvin) than that of Xenon light (approx. 4,000 Kelvin). This comes close to what people are used to seeing. The driver does not tire as quickly and is more relaxed. In addition, the white LEDs are a convincing choice thanks to their quick response time, and two functions (such as low beam and daytime running light) can be covered with one light source. LED headlamps also open up new, far-reaching styling options and thus great differentiation potential for vehicle manufacturers. In the Cadillac Escalade Platinum, car drivers experience a light experience with the LED headlamp that is on a par with xenon light. The light color is even closer to daylight, so drivers do not tire as quickly and are much more relaxed at the wheel.
Hella’s full-LED headlamp for the Cadillac Escalade Platinum has been realized using various transmissive optical elements. Free-form glass projection lenses are being used for the first time anywhere in the world; thanks to their individual optical design, each area of the lens is responsible for a certain part of the light distribution on the road. Of the seven glass lenses used in a headlamp overall, only two are completely identical, all the others are of different shapes.
The low beam is generated by five optical units arranged underneath one another and situated at the outer edge of the headlamp housing. The topmost of these five optical units is a round projection lens with a 60-millimeter diameter. The lens is used to generate the range of the low beam on the right-hand side of the road (asymmetrical “light finger”), while the four cushion-shaped freeform glass lenses realize the symmetrical basic light distribution with large dispersion which provides homogeneous illumination of the close range in front of the vehicle. The daytime running light function will be realized by dimming the low beam. Two additional free form projection lenses are responsible for the high beam; these are situated at the inner edge of the headlamp housing. The position light is designed as a light-guide rod placed vertically between the low beam and the side marker, with the light of two white standard LEDs being coupled in. On the very outer edge of the headlamp, the side marker light shines from seven vertically arranged amber standard LEDs. Direction indicator and fog lamp in the Cadillac Escalade Platinum are mounted in the lower area of the bumper.
Hella is using newly developed multi-chip LEDs as light sources for low beam and high beam. A high-performance ventilator developed especially for the particularly demanding requirements in the automotive sector is responsible for thermal management in the headlamp, and takes over the active cooling and ventilation of the LED chips.
Approval situation for LEDs in headlamps:
In the USA, headlamps with LEDs for main lighting functions are already permissible according to the SAE standards applicable there. In Europe, or in the area governed by ECE regulations, approval is expected by 2008. Signal functions in the headlamp (direction indicator, side marker light, position light, daytime running light and cornering light) are already permissible, both in ECE and SAE areas.