LED headlights use free-form optics and ceramic frame

May 22, 2008
CeramTec produced the ceramic frame, and Docter Optics developed the free-form lenses, for Hella LED headlights used on the Cadillac Escalade SUV as standard equipment.
Two suppliers recently described their involvement in the LED headlights that Hella KGaA Hueck & Co. is supplying for the Cadillac Escalade Platinum Sports Utility Vehicle that enters serial production this summer - see Related Stories.

The distinctive design of the LED headlamp is based around seven free-form glass projection lenses that are being used for the first time anywhere in the world, according to Hella.

All-LED SUV headlight The projection lenses were supplied by Docter Optics, while the multi-chip LEDs are mounted on a specially developed CeramCool ceramic frame produced by CeramTec AG’s Electronics Division.

Docter Optics’ projection lenses

Docter Optics produced the sophisticated “free-form” lenses for the Escalade’s full-LED headlights. Free-form lenses make it possible, for example, to “shape” light to meet the needs of a specific application with exceptional precision, the company says.

The assemblies in the Escalade integrate not only high- and low-beam functionality, but also daytime running lights and position lights as well as the side markers that are obligatory in the US.

Docter Optics' proprietary DOC3D process permits large-scale production of aspheres and free-form lenses for sophisticated illumination applications, including economical production of special lenses for these LED headlights.

CeramTec’s ceramic frame

The partially transparent frame is produced using a dry pressing process and is then metallized. To meet strict customer requirements, a special process had to be developed that observed the lowest tolerances and used an absolutely faultless metallization, CeramTec said.

Each headlight is equipped with 7 LEDs and subsequently fitted with the ceramic CeramCool. The LED solution is particularly robust and works reliably in temperatures ranging from -40°C to +125°C.