The Weight of History
The LCD answer is focused on hi volume products like TVs and mobile phone handsets. LCD capabilities have been improving every year, and will continue to do so for the foreseeable future. Each improvement lowers the marginal cost of production, driving down price and creating a moving target for any new technology. If an OLED producer really wants to beat LCD, he has to plan that his CAPEX today will beat LCD targets 5 years from now, when the plant is fully up to production.
If you’re beating the drum for some limit on the capabilities of LCDs, you’re backing a loser. There is plenty of precedent, but the best analogy I can think of at the moment is magnetic data storage. For at least 12 years, and probably a lot longer, the optical storage pundits have been predicting the death of the magnetic disk.
Every other year it seems engineers have reached a fundamental insurmountable technology barrier, and only holographic data storage, magneto-optical disks or some other technology can carry us past that barrier. And then someone solves the problem, just in time. Oddly enough if you take a step back and look at the change in capabilities over time, they follow a smooth curve, despite the need to overcome fundamental technical hurdles.
This is demonstrates a basic law of technology development, namely that technical progress is easily predictable over long time horizons, even if the solutions allowing that progress are unknown. You probably know the most famous corollary to this, i.e. Moore’s law.
Folks touting the end of LCD TVs and monitors are fighting the inertia of history, and almost guaranteed to be wrong. There is no such thing as a special case; if anything, the complexity of LCDs makes improvement even more likely.
If we compare the LCD commercialization timeline to the OLED commercialization timeline, and assume that both curves should roughly be the same, an interesting thing happens. LCDs were invented at RCA around 1962. It was not until 1996, 34 years later, that a real display market emerged for liquid crystals, and it was only this year (2008) that LCD TVs finally outsold the old CRTs (46 years, if you’re counting).
OLEDs were invented at Kodak in 1983. Given the same timeline for commercialization, 2017 is the earliest we should expect a real commercial breakthrough, and market saturation will likely occur around 2029, give or take a few years. If we fudge the numbers downward because of other technological advancements, we’re still realistically looking at 2010 for a commercial breakthrough and 2020-2025 for market dominance.
The problem with the original OLED answer is that it focused on the same law mentioned above, without regard to the market dynamics. It is true that this expansion of Moore’s law operates independently of any knowledge of market dynamics. The problem here lies in the assumption that OLEDs must compete with LCDs. Let’s decouple them for a minute and assume that OLEDs are complementary to liquid crystal display technologies.
The major value propositions of OLED displays are that they are thin, energy efficient, and have a high contrast ratio. They can also be easily made transparent, but let’s not confuse the issue. Big drawbacks today include poor production yields, high production costs (still an order of magnitude too high), and lifetime and scalability issues.
In contrast, LCDs are inexpensive, easy to produce in volume and readily scale to ever larger displays. The two areas where technology advancement consistently produces high margin products and where consumers are willing to pay extra are in ever larger displays (Aren’t you just dying for a 104-inch TV?) and thinner, more energy efficient displays. Personally, I prefer the latter, but hey, if I can get it on an 84 inch TV, even better.
The real drag on LCD cost and power consumption is the backlight. Usually this is a fluorescent lamp that is continuously on while the display is turned on. Lamps are often edge mounted on a prism that lies behind the display, and even when they are directly mounted behind the display, the settings are binary – on and off – and directly linked to the power button. The backlight assembly is pretty thick (typically 1 cm or more), delicate and heavy.
Samsung and several other firms have demonstrated LED backlights that are dramatic improvement in quality and efficiency over CCFLs. LED backlights have great potential, but they are still more costly and thicker than OLEDs. Perhaps a 100 micron thick, white OLED might make a descent backlight. And if you could pixelate the backlight, you could get true black (and thus high contrast ratios) in an LCD.
It turns out in practice that this arrangement works very well. The backlight does not need very many pixels for selective dimming to have a dramatic improvement on picture quality. In fact, as few as 16 pixels has a dramatic effect. Using an independently driven 16 pixel (each pixel being 1/16th the area of the display…) LED backlight WINTEK demonstrated contrast ratios approaching 100,000 to 1; and Samsung has several LED backlit LCD TV products on the market, including the 57 inch LN-T5781F which went on the market July 1st, with a contrast ratio of 500,000 to 1.
The proof is in the pudding, so to speak. One could argue that inorganic white LEDs are cheaper and more efficient than today’s white OLEDs, and you’d be 100% correct. OLEDs also run a little hotter than LEDs and have lifetime issues.
But you have to remember that there are no full scale gen 6 or later OLED TV production lines running today (although Samsung SDI is investing in a gen 6 line at this very moment, and Kodak is working hard to create OLED compatible glass at gen 8 sizes and above), and very few pilot lines, so expect to see prices drop dramatically and most of the production related lifetime issues go away as volume rises.
Novaled, a major player in OLED innovation, provided data at SID that suggests white OLED efficiencies will meet or exceed that of current white LEDs by 2010 (see the OLLA project final press release) The demonstrated contrast ratios are extremely close to OLED TV contrast ratios, and arguably so good that any improvements will likely exceed the ability of all but the most expert viewers to notice.
Furthermore, even in production models, these hybrid TVs use up to 50% less energy than a conventional flat panel LCD – again, a metric very closely approaching proposed savings from OLED TVs. Unlike OLED only TVs, for hybrid (O)LED/LCD TV yield isn’t important –a few, or even very many, dead subpixels on the backlight can be compensated for digitally.
So here is a viable product that is actually going to come onto the market in the near future that combines OLEDs and LCDs to create an improved TV. OLEDs win; LCDs win – and everyone goes home happy, except possibly the backlight makers.
The best part of this scenario (right after the fact that it is real), is that it creates an independent market for OLEDs. This is a niche that only OLEDs or thin-film LEDs can fill. Now OLED makers can reinvest in production capacity and have the breathing space to solve production issues and come up to minimum efficient scale for other applications, which I won’t even try to guess at here.
Of course, this is not just idle speculation. The major players in the OLED industry came to similar conclusions a long time ago. Universal Display Corporation was issued a basic patent on the idea in May of 2005 (US Patent 6900458). Just this January, Novaled and OSRAM demonstrated white OLED lighting that is not only suitable for home interior use, but (as Novaled hinted at in their presentation at SID) would likely work just as well for backlight applications.
In early 2007, OLED-T and Microsharp received more than $400,000 from the U.K.`s Department of Trade and Industry Electronics and Photonics Collaborative R&D to develop working OLED backlit LCDs. And the big consumer electronics players like Toshiba, Samsung and Sony continue to develop both LED and OLED backlight strategies.
If you’ve read through all of this you might have forgotten how we started, and maybe you’re not even miffed that I still haven’t answered the original question. The answer is that the question is wrong. The query should have been “What will be the breakout product for OLEDs, and how will various parts of the supply chain benefit from OLEDs?”