OLED lighting seems to have been on hiatus as of late. While there were no serious setbacks in 2012, it would be hard to say that the industry moved closer to becoming the mass market product that it was expected to be in the 2015/16 time frame.
On the positive side there were both new OLED lighting products and new OLED lighting companies that emerged. But, the industry has yet to resolve key technical issues that NanoMarkets feels are critical to the industry's success, namely panel size and lifetimes.
What Won't Make a Difference: Luminance and Efficacy
Note that we haven't included "efficacy" on this list. This may seem odd. Lighting efficiency is the number one reason given for creating OLED lighting in the first place. But that is precisely the point. The evidence of the past three to four years is that OLED lighting efficiency is on a growth curve that will take it smoothly to the 100 lm/W necessary to make OLED lighting go mass market in the 2015 to 2016 period. So, the success of OLED lighting in that timeframe will be determined by factors other than efficacy.
Something similar can be said about luminance. It seems that luminance, like efficacy, should be good enough to mainstream OLED lighting by 2015/2016. And while OLED lighting must compete with CFLs and HB-LEDs on luminance to some extent, it will be hard to make direct comparisons in most cases, because OLED lighting is a panel, while the other two types of lighting are (more or less) point sources. Improved luminance for OLEDs is expected and will be welcomed, by the market, but NanoMarkets doesn't expect it to be a critical factor in the success or failure of OLED lighting going forward.
Panel Size: A Hidden Drag on the Future Success of OLED Lighting
By contrast, NanoMarkets believes that not attention is being paid to panel size in the OLED industry. The OLED lighting panels that are currently available are typically quite small; entirely suitable for small decorative lights or table lamps, but not suitable at all for providing general purpose illumination in a home or office. Offices are, in fact, where – according to conventional wisdom, anyway – OLED lighting will take off first as a mainstream general illumination technology.
The way in which this is supposed to happen is not usually made explicit, but the deployment scenario that most vendors seem to have in mind is that OLED panels will gradually replace traditional fluorescent fixtures in offices, with the main market drivers here being energy efficiency and aesthetics. This is a compelling vision of a future OLED lighting market, but currently it could only be achieved by stitching many OLED tiles together. This would be an expensive process and the lighting effect may not be as continuous as one would get from a single tile.
In our view, unless this situation changes, these negatives could prove daunting enough to turn an emerging niche OLED lighting market into no market at all!
There are certainly reasons for optimism here. GE has managed to create a 2 x 2-ft OLED lighting panel using a 4 x 4-array of OLED panels. Philips says in a few years it will be able to offer 1 meter x 1 meter panels. Panasonic says it will have 600 mm x 600 mm panels by 2019 and the Korean firm, Jusung Engineering has already built a 730 mm x 920 mm panel.
But while all the major OLED lighting firms are trying to make larger panels, most – possibly all -- of the large panels that have been showcased to date are not commercial products and there is no reason to believe that any firm can yet make large enough panels with a decent yield; one small defect can fail the whole panel depending on design.
Low yields will more or less guarantee that no one will be able to make any money in the OLED lighting business. And there are plenty of other challenges on the way to making OLED panels bigger including non-uniform brightness due to high resistance of transparent electrodes; resistive loss in large-area panels; less effective light extraction (outcoupling); and creating drivers with low loss and capability of providing large currents.
Office Light Lifetimes
Lifetime is another area of concern for OLED makers. In the one real success that we have seen to date for OLEDs – small mobile displays – lifetime hasn't mattered that much, because cell phones don't usually survive beyond two years at most. OLED lighting for residential applications may not be a big deal either, because lighting in homes tends to get turned off.
But in offices, lighting is on all the time; literally in some cases. We think that OLED lighting could probably compete reasonably effectively with fluorescent lighting and this is a plus because the market OLEDs will be attacking in the office space are primarily fluorescent at the present time.
Our concern though is OLED lighting could lose out in the critical office lighting market to LED lighting. While LEDs may not be able to match the aesthetics of OLEDs, they can still outperform OLEDs on lifetimes, which are an important determinant of lighting economics. And for large offices in particular, economics can be everything.
HB-LED lighting can offer around 60,000 hours of lifetime. So to really penetrate the office lighting market OLEDs are going to have to match this. Otherwise they will be restricted to markets where the first concern is aesthetics; this would mean offices of architects, large consulting firms, etc. Niche business at the best.
As NanoMarkets has noted in our reports, OLED lighting panels still have a serious challenge competing with HB-LEDs. Philips believes that OLED lighting panels will reach 40,000 hours by 2018, which isn't that far away from HB-LED performance, but is after the consensus take off point for OLED lighting's market take off. LG says it can reach that level of performance by 2015, and there are research devices in the OLED lighting space that can beat commercial LED lighting in terms of lifetimes.
However, research devices are exactly that and in terms of both lifetimes and size, the jury is still out on whether OLED lighting will be good enough to succeed in the marketplace.