Optical concepts for a combined low-beam and high-beam out of a single LED

Tobias Schmid1, PeterBrick1

1OSRAM Opto Semiconductors GmbH, Regensburg,Germany

Abstract:Inthepast,manyautomotivelightingfunctionshavebeenrealizedbydesignsthatstaticallyprovide specific illumination patterns. In contrast, existing adaptive designscomprise eithermoving shutters orelectronically-complex matrixsources.

Inthisarticle,weexplorealternativeoptionsforacombinedlow-beamandhigh-beamoutofasingleLED.

In order to reduce the electronic complexityand at the same time to come up with a compact LED forthe light source we resort to two rows of chips arranged on acommon carrier. The two rows canbe independentlydriven.

Adjacentprimaryopticscollectstheemissionofthetwoclosely-spacedchiprowsandsimultaneouslyprovides a way to separate respective contributions. The subsequent secondaryoptics is basedonconventional reflector/projectorconfigurations to realize low-beam and high-beamdistributions.

Insuchsystems,efficiency,tolerances,andsystemsizeareevaluatedwithrespecttodifferentprimary optics based on refraction,reflection andTIR.

Keywords: LED,optics, forward lighting, low-beam,high-beam.