Is laser the next source for automotive exterior lighting?

Is laser the next source for automotiveexterior lighting?

Authors:

P.Albou, P.Racine, B.Reiss, Valeo LightingSystems, France

Followingthe evolution of light sources since years, from halogen bulbs, to Xenon andnow LED, this question may be truly valid.

The targetof this paper is to bring some answers to this point.

At firstthe main characteristics of this king of source, its benefits and constraintswill be described, before presentation of some applications.

Theseapplications start first with really new design proposals, thanks to thesource, which could directly impact the outer shape of the vehicles, as we sawin the past with the development of clear (i.e. without optic) outer lenses forhalogen and xenon bulbs. More specifically, these designs with 10 mm heightoptical system, allow very thin front shape, which will also have a directpositive impact on vehicle aerodynamism in order to reduce CO2 emission. Ofcourse, new design proposals must come without any compromise on performancesvs. current high range systems; low height design with high performances lowbeam and high beam is the first application described in this paper.

Using laserdiode to really increase performances of existing design is a secondapplication. If many low beam can be considered as having very goodperformances and remaining in line with regulation, the question is raised forhigh beam. Due to general design, maximum illumination of high beam aregenerally between 100 and 150 lx, while regulation allows a factor 2. Highluminance of laser source will then make it possible to reach performancesclose to allowed limit, while maintaining compact design. Example of laser spotmodule is presented in the paper, as well as possibilities for integration andreal benefits on beam pattern.

Before theconclusion,  the last part of the papershows  new functionalities of frontlighting which will be possible thanks to laser source and projection systems.Among these new functionalities, there are high resolution Glare Free High Beam,marking light, road marking, …