LED Technology in Rear Lamps

Using red and amber LEDs for rear functions is already state of the art. LEDs create light by voltage-induced recombination processes in a semiconductor layer. The emitted light is determined in its colour by the internal structure of the LED. Compared to conventional incandescent bulbs, the main advantages of LEDs are their high lifetime (up to 100.000 hours), their low energy consumption due to the efficient conversion of electrical power into optical power and the small depth of the modules. LEDs also offer a vast variety of fascinating innovative styling possibilities. Moreover, the switch-on-time is very short. This provides a safety benefit to following vehicles in situations requiring fast breaking response. The light intensity of the break light can be adapted to the breaking intensity. This allows the development of adaptive rear lamps, which can adapt their behaviour to different driving conditions.

LEDs also need drivers (ECU) to give power supply to these special sources and to provide interfaces to the electrical networks of different cars, providing also sometimes diagnostic functions.

Applications with LED-Technology

First applications of LED technology go back to the first half of the nineties with the development of central high mounted stop lamps (CHMSL) with LEDs in 5 mm package for the Japanese market. In the meantime, all functions can be equipped with LEDs. These functions are tail light, fog light, turn indicator, break light and back up light.

In 2005 Automotive Lighting started the first mass production of a rear lamp with LED position light, break light and turn indicator into the market.

Space requirements with LED-applications in rear lamps

Space and Depth of Taillamps
- X = actual bulb version
- Y = LED-modules with internal moulded elements
- Z = LED-modules on flexible boards

LED rear lamp