Illuminating the OLED Lighting Roadmap

By Dr Peter Harrop, Chairman, IDTechEx

Organic Light Emitting Diodes (OLEDs) have more market potential than any other form of potentially printed electronics. This is because they are proving useful for both electronic displays and lighting. Indeed they also have great potential for signage, a major requirement intermediate between these two. Anyone looking at the enormous and expensive plasma displays in airports that display simple logos and signage will realise that there has to be a better way with signage. Potentially, “wallpaper” electronic signage would use far less power and have both lower capital cost and installation cost.

Roadmap
The roadmap for progress in improving the capital cost, flexibility and power consumption of OLEDs is now becoming clear and it is good news all the way. Roadblocks of inadequate lifetime, particularly for bright white light, are also being overcome within the new timescales, which are shown below. Little progress is expected in improving the efficiency of incandescent or fluorescent lighting. They are yesterday’s products. As we noted, OLED lighting is already much more efficient than incandescent lighting and it will surpass fluorescent in 2008. Markets will open up for versions on flexible substrates in particular, because installation cost is so low and the format is so versatile and appealing. However, capital cost of long life white versions below that of conventional lights will not be on offer in mass production until around 2016 unless further major breakthroughs are made. In late 2006, OSRAM forecasted that the first major sales of OLED signage will be in 2008, though not with all the intended attributes.

Breakthrough
In late 2006, a breakthrough was announced Royal Philips Electronics and Novaled. It is a record combination for efficiency and lifetime of high-brightness OLEDs. Philips Lighting, Philips Research and Novaled collaborated on the research effort that produced the breakthrough. The new record for a white OLED’s power efficiency was 32 lm/W with color coordinates of 0.47/0.45 and a CRI of 88 at a brightness of 1,000 cd per meter-squared. That device structure shows a lifetime of more than 20,000 hours, which is promising for future commercialization of the OLED technology for lighting applications.