When OSRAM Sylvania unveiled the JOULE™ LED lighting system in 2003, its goal was to provide OEM designers with a reliable, industry-standardized LED light source that simplifies the design process. They pioneered LED standardization with the JOULE system, allowing OEMs to offer their customers a high quality, standardized automotive LED system without the complexity or cost of a custom assembly.
OSRAM succeeded in their endeavor with the development of the JOULE. The JOULE system was first installed on the 2006 Mercury Mountaineer and the 2008 Chevrolet Malibu LTZ. But five years after the inception of the product, it’s no surprise that OSRAM was looking to revamp their product to better serve the market they created and stay ahead of its competitors.
In essence, they needed to keep their innovative product innovative.
During the redesign process, one aspect of the JOULE LED lighting system that needed an overhaul was the light pipe. The purpose of the light pipe is to transfer light from the LED source to the output without losing any luminosity in the process. This requires pinpoint accuracy of the lightpipe design and high optical clarity in a dimensionally stable clear acrylic polymer (PMMA), properties that are generally difficult and expensive to produce simultaneously.
“The light pipe is an integral part of the design as it transfers the light from the JOULE LED source to an optical reflector for use in vehicles’ tail lamps,” explained Kim Albright, Senior Product Development Engineer at OSRAM Sylvania. “The ability to ‘place’ the generated light where needed is a technical challenge that few materials on the market can solve flawlessly.”
So how could OSRAM maintain their goal of offering a standardized, cost effective alternative to custom assemblies without sacrificing quality?
Finding the Right Part
OSRAM had their work cut out for them. Being involved on the part design and selection for the newest generation of the JOULE system was DTI Molding Technologies, an Illinois-based company.
“The design for the newest JOULE LED lighting system called for some very complicated molds, particularly for creating the light pipe. Finding the right material was key,” said Stacey Morton, Plant Manager for DTI Molding Technologies. “The molding cores for the light pipes are very sensitive and tend to scratch. For the light pipes, scratches are unacceptable. We needed to find an acrylic resin that could achieve a high level of optical clarity, but also not damage the cores during processing.”
The resulting trial and error process evaluating 5 acrylic polymers would eventually lead them to Evonik Cyro’s ACRYLITE® SuPure acrylic polymer.
“After sampling multiple grades and types of materials, we found the Evonik Cyro material’s quality and performance to be ideally suited to our application,” added Albright. “You see, the ability to create quality custom molded light pipes that meet the stringent performance requirements of automotive applications made finding the right solution difficult. We knew the ACRYLITE product would perform as we needed it to from both a manufacturing and an in-the-field perspective.”
ACRYLITE SuPure acrylic polymer is ideal for light pipes and light engines. It is designed to deliver extreme clarity for product applications in which no defects can be detected by the naked eye under varying light conditions. The lack of defects allows for maximum light transmission efficiency with minimal loss.
“We chose ACRYLITE SuPure because it was the only acrylic that both stabilized the molding process for us and matched OSRAM’s high optical expectations. We have seen very little variation lot to lot. It’s a great resin,” continued Stacey. “Additionally, Evonik Cyro was very helpful. We needed to implement a new mold, and they came to our plant and helped with the final tweaks to get the best possible results.”
The polymer proved to have the highest light efficiency of any clear polymer class they tested. Furthermore, it had low internal light losses, superior optics, weatherability, AMECA listing, and was competitively priced. Additionally, the weatherable quality of the acrylic lends to lower maintenance costs over time and increases the longevity of the overall product.
Getting the Green Light
Another area of improvement realized by the new ACRYLITE SuPure acrylic polymer was green design. The automotive industry has seen a boom in the need for environmentally-friendly manufacturing. More and more cars are attaining higher fuel efficiency with lower overall emissions. This is the area where green design has taken center stage for automobile manufacturers, but other areas can be equally improved upon. Lighting is one of them, specifically in terms of optical material selection for LED-based applications.
“DTI Molding sees this as one of the changes that is coming in the injection molding,” says Morton. “We start looking at green resin and how we can apply this to our manufacturing processes. With Evonik Cyro’s acrylic, we can apply this to headlight design through the JOULE system, and in the future, other lighting systems.”
ACRYLITE SuPure’s clarity produces a high light transmission of 92%, complementing the brilliant LED source used in the OSRAM JOULE system. The result is a high efficiency system that delivers bright illumination while consuming less power.
There are other environmental benefits associated with the ACRYLITE SuPure acrylic. Lighter than glass optics, it helps reduce the overall weight of automobiles to improve fuel efficiency. ACRYLITE SuPure acrylic also eliminates the need for coatings and lasts longer than glass alternatives, reducing waste.
Given such benefits, it’s no wonder that OSRAM Sylvania and DTI Molding chose ACRYLITE SuPure to help bring the JOULE Light System, an already innovative product, up to the ever-increasing standards of the automotive industry.
“JOULE, the very name of the product line conjures both images of energy savings and a polished and gleaming gemstone. The crystal clear appearances of the light pipes add both aesthetic and functional performance to our part, helping give it its jewel-like appearance,” said Albright. “Customers have commented and come to identify the unique look and styling of our part, and one of the key aspects to that is our crystallike appearance with the light pipe molded out of Evonik Cyro’s material.”
“In the realm of engineering grade automotive-qualified, optically-clear materials, the ACRYLITE SuPure has matched our requirements perfectly.”
About OSRAM SYLVANIA Automotive Lighting
OSRAM SYLVANIA, together with OSRAM GmbH, is the world leader in automotive lighting for original equipment manufacturers (OEMs) and the aftermarket. The company’s global automotive lighting division has its principal North American operations in Hillsboro, N.H., with nearly 700 employees. In addition to TS 16949, this facility has also achieved ISO 9001 and 14001 certifications. Automotive Lighting designs, develops, manufactures and markets state-of-the-art automotive light sources, including auxiliary, advanced halogen, LED and highintensity discharge lighting for interior, exterior and forward lighting applications. More than 400 lamp types are produced for cars, trucks, and electronics in facilities throughout the U.S., Europe, and Asia. Automotive applications for OEMs are marketed under the OSRAM brand while products for the aftermarket are sold under the SYLVANIA brand. For more information, visit www.sylvania.com/auto.
Evonik Cyro LLC
Evonik Cyro LLC is an Evonik Degussa Corporation group company. Headquartered in Parsippany, NJ, Evonik Cyro is a leading manufacturer of acrylic sheet and molding compounds, and bulk and performance monomers. Cyro manufactures and markets its acrylic sheet products under the ACRYLITE® trade name in the Americas. These same products are manufactured and marketed under the PLEXIGLAS® trade name on the European, Asian, African and Australian continents.
Evonik Industries is the creative industrial group from Germany which operates in three business areas: Chemicals, Energy and Real Estate. Evonik is a global leader in specialty chemicals, an expert in power generation from hard coal and renewable energies, and one of the largest private residential real estate companies in Germany. Our strengths are creativity, specialization, continuous self-renewal, and reliability. Evonik is active in over 100 countries around the world. In its fiscal year 2008 about 41,000 employees generated sales of about Euro 15.9 billion and an operating profit (EBITDA) of more than Euro 2.2 billion.
In so far as forecasts or expectations are expressed in this press release or where our statements concern the future, these forecasts, expectations or statements may involve known or unknown risks and uncertainties. Actual results or developments may vary, depending on changes in the operating environment. Neither Evonik Industries AG nor its group companies assume an obligation to update the forecasts, expectations or statements contained in this release.