LEDs set highlights in car interiors

November 08, 2013 // By Christoph Hammerschmidt
Across all segments of the automotive market, manufacturers see increasing demand for innovative interior lighting solutions. Supplier Hella KGaA, a tier one supplier dedicated to lighting technology, announces a number of recent design-ins with several OEMs. To meet the increasing demand for highly customizable designs, the company has devised a spectrum of options from elongated light guides to diffuse lighting for footwell and map pockets.

In the luxurious Range Rover SUV, available since 2012, customers can chose their ambient lighting from a particularly ample option list. Future car owners have the choice of ten different colours, from "Spark Blue" to "Racing Red", plus, of course, White. To create the desired impression, Hella utilizes light guides, integrated in the map pockets of the doors as well as in the centre console. They obtain their light from a total of eight RGB modules, each incorporating three different LEDs for red, green and blue light. A control node at the LIN bus blends these three basic colours to obtain the desired light colour. In addition, the LIN module also controls the brightness. As a part of the production process, the LEDs are selected in groups that match in terms of brightness as well as of colour. After the LEDs are surveyed, a correcting matrix is generated for each LED chip to guarantee a uniform, even colour impression.

The Seat Leon - Seat's companion to the Golf from parent company Volkswagen - also utilizes lighting solutions from Hella. Seat's engineers integrated an indirect illumination in the door panel. A bi-colour LED module enables interior lighting according to the selected driving profile - white in the comfort and eco mode, red in the sport mode. Since the light is fed into the light conductors from both ends, the light impression is particularly homogeneous.

Fig. 1: Each RGB module consists of three different-colored LEDs (red, green, blue), whose light is coupled into a light guide.

Adam, the new subcompact from Opel / Vauxhall, also offers an unusual wide range of interior lighting choices. The MultiColor LED lighting option available for this vehicle can generate eight different colours. The centre console then is illuminated in the colour selected, as well as the passenger footwell and the map pockets in the doors. An innovative detail is the optional backlighting of the glove compartment