DUESSELDORFf, Germany—Liquid silicone rubber is a key material used in new adaptive driving beam headlights, which automatically shine less light on occupied areas of the road and more light on unoccupied areas.
At the recent Silicone Elastomers World Summit in Duesseldorf, a materials supplier and a molding specialist gave a presentation on how to mold the complex LSR parts needed for the ADB matrix lenses.
Hannes Rieger, head of research and development at Oftering, Austria-based Elmet Elastomere Produktions und Dienstleistungs GmbH, a mold maker and LSR mixing and dosing equipment producer, prepared the presentation, which was given by Francois De Buyl, R&D and technical service and development manager at Midland, Mich.-based Dow Silicones.
LSR matrix lenses with integrated optical lens and light guide functions were first produced by Lippstadt, Germany-based Hella GmbH & Co. KG on the 2016 Mercedes-Benz E-Class car and later on the Porsche Panamera, molded by Nuremberg, Germany-based Optoflux GmbH with 84 light guides in three rows.
Meanwhile, advances in light control have enabled still fairly demanding, if not quite so complex, ADB matrix lens/lightguide parts with less than 84-pixel lightguide systems. These mostly two-row integrated high-beam and low-beam ADB lens/lightguide parts increasingly used as LSR optics have spread to other vehicles, with various examples seen in live demonstrations by injection molding machinery producers at various plastics industry trade fairs.
Such ADB optics now consist of 10-24 lightguides of 6-24 millimeters in length with four or more facets and with 2-15 mm thick out-coupling lens sections. Lightguide draft angles vary between 0.5º and 10º or more, Rieger said, pointing to stress-free demolding of such complex parts being facilitated with integrated side grip elements and use of vacuum end-of-arm tooling (EOAT) for part removal from the mold.