Optical concepts for a combined low-beam and high-beam out of a single LEDTobias 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. |