The race is on to bring OLED technology into mainstream lighting. Some of the main players of this huge potential market have collaborated together in projects to accelerate its progress and help European lighting companies to maintain their leadership at worldwide level.
CombOLED is a 7 million euro (about $10.5 million) project partially funded by the European Community which started earlier this year. Their goal is to achieve cost effective OLED lighting solutions with the combination of new device structures, advantageous manufacturing solutions and less complex materials through the necessary investment in research and development to overcome the technical barriers that currently limit the product to niche market.
"The objective of this project is to create the necessary conditions for introducing the new light sources into lighting applications", said Bernhard Stapp, Head of Solid State Lighting at OSRAM Opto Semiconductors.
The CombOLED consortium resembles an OLED supply chain from substrate supply via device manufacturing until application design and prototype realization. The 7 European partners include: Siemens, Germany; Schreiner VarioLight, Germany; PPML Lighting Revolution, Italy; Universitat de València, Spain; Leti, France; Saint Gobain Recherche, France and Osram Opto Semiconductors, Germany who will co-ordinate the project.
The major goals which are related to different application fields can be summarized as follows:
1. A new coated substrate technology that is more cost effective than today's standard Indium-Tin-Oxide coated high-end glass.
2. Stack Technology that combines non-complex and cost effective deposition methods with a high device performance based on either Small Molecule or Polymer materials or combinations of them (and presumably the intermediates as well)
3. Deposition methods that are able to deposit layers of organic materials at low area costs / high speed.
4. A backside contact (top-contact) that is transparent to visible light enabling transparent devices. Clearly windows that double as lights are one possibility.
Several research programs have already been carried out and other projects are still ongoing to improve the performance characteristics of the OLED tiles. See below for a summary of the history of the main achievements at worldwide level, none being to any standard test method:
- June 2008: Universal Display Corporation demonstrated white OLED with a power efficiency of 102 lumens per watt (lm/W) at 1000 cd/m2 using its proprietary, high-efficiency phosphorescent OLED technology.
- June 2008: Philips Research and Novaled, together with their partners as part of the OLLA project reached an efficiency of 50 lumens per watt combined with a lifetime of over 10.000 hours at 1.000 cd/m2 initial brightness.
- November 2007: Novaled announced the achievement of an OLED device with an efficiency of 35 lm/W at a brightness of 1,000 cd/m2 and a lifetime of above 100,000 hours. The device exhibited a color rendering index CRI of 90
- June 2007: Universal Display Corporation announced a phosphorescent white organic light emitting diode (WOLED) with a power efficiency of 45 lm/W at 1000 cd/m2
- November 2006: Scientists at Pacific Northwest National Laboratory (PNNL) created a blue organic light emitting diode with an external quantum efficiency (EQE) of 11% at 800 cd/m2 exceeding their previous record EQE of 8%
- June 2006: Philips Lighting, Philips Research and Novaled's labour established an unprecedented record combination when it came to efficiency and lifetime of high-brightness white OLED. Their collaboration resulted in 32 lm/W a CRI of 88 at a brightness of 1000 cd/m2 with a lifetime of over 20,000 hours
- November 2005: Osram Opto Semiconductors Inc. successfully demonstrated a white organic light emitting diode with a record efficiency of 25 lm/W, a record for polymer-based white OLED
- October 2004: Universal Display Corporation and its partners at Princeton University and at the University of Southern California succeeded in developing a white phosphorescent OLED (PHOLED) that achieved a record efficiency of 20 lm/W
- April 2004: General Electric Global Research achieved a major breakthrough, developing a fully functional 2ft x 2ft, light panel that produced more than 1200 lumen of quality white light with an efficiency of 15 lm/W.
The OLLA project has just concluded after reaching its goal of an efficiency of 50 lumens per watt combined with a lifetime of over 10.000 hours at 1.000 cd/m2 initial brightness and it will be followed up with a new project - The OLED100.eu project which is due to start on September 1, 2008 and run for three years.
The new project has a budget of 19.96 million euro (about $31 million) and the members, who include Philips, Osram Opto Semiconductors, Siemens, Novaled and Fraunhofer IPMS, are due to receive 12.5 million euro (about $19 million) from the European tax payer. The five main objectives are: power efficiency of 100 lumens per watt, a lifetime in excess of 100,000 hours, an increase of area to 1 meter by 1 meter and a low cost of manufacture at 100 euro per square meter or lower.
Another OLED project "TOPLESS" (thin organic polymeric light emitting semiconductor surfaces) is focusing on commercially viable lighting products. See an earlier IDTechEx article Thorn OLED Project UK has potential to replace conventional lighting. Project partners include Thorn Lighting, Sumation (the joint venture materials company formed by CDT and Sumitomo Chemical before CDT was bought by Sumitomo) and the University of Durham in the UK.
For more information read A major milestone - white OLED technology exceeds 100 lm/W; The OLLA project delivers its final milestone and OLLA final event symposium, Eindhoven 12.8.08.
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