For rear lighting Valeo has developed MicroOptic technology, which replaces standard optics (such as lenses and reflectors) with a light guide. “LEDs are a point source, and from a style point of view we want to move away from being able to see the individual pixels and have something more homogenous,” said Jean-Paul Charret, core engineering director with Valeo Lighting Systems. This development is in response to feedback from Valeo’s customers and from vehicle drivers. LEDs are chosen over bulbs as the light source owing to their small size and high brightness.

The light guide is typically a diffuser sheet or a light pipe. Lightguiding screens can be used as stop lights and turn indicators as well as tail lights. Charret says that rear combination lamps using a homogenous light-guiding screen have been demonstrated on the Renault Egeus concept car and are ready to go into production. The full article can be found in the December 2005 issue of LEDs Magazine Review at www.ledsmagazine.com.