OLED TV Prices May Be Lowered By New Polymer Development

Mike Wheatley

There’s been a lot of excitement generated by the thought of having OLED TVs taking pride of place in our living rooms over the course of this year, but this has yet to transpire due to the extremely high cost of manufacturing the televisions.

OLED TV prices may be lowered by new polymer development

As we reported previously on HDTVTest, OLED TV models like the LG 55EM970V and Samsung’s 55-inch ES9500 are likely to cost in excess of £10,000 if and when they do hit UK shops, but this isn’t the only thing that’s holding the technology back. Another problem is making the things – display panel makers simply don’t possess the capability to make enough of them, and this problem is not only due to the lack of production facilities available.

One of the biggest headaches panel makers have is that OLEDs rely on a rare material called indium, which is also used in solar panels. With OLED displays, indium is mixed with tin to make indium tin oxide, or ITO, which is used as the anode in the screens.

For years, indium has always been viewed as the most ideal material for anodes, due to its conductive and transparent properties. But times have changed, and with the material become increasingly more expensive and difficult to obtain, researchers have been forced to try and come up with an alternative.

And so we have some good news for panel makers at long last, with reports suggesting that a viable substitute for anodes has finally been identified. Scientists working together at Iowa State University’s Microelectronics Research Center and the US Department of Energy’s Ames Laboratory believe they have finally hit on to something: a 15-year old polymer poly (3,4-ethylene dioxythiophene):poly (styrene sulfonate), known more simply as PEDOT:PSS.

Now PEDOT:PSS has been considered for use in OLED televisions before, only to be discarded when engineers decided that the material lacked the transparency and conductivity required. However, display panel makers are now giving it second thoughts after the Ames scientists discovered a way to make the substance more transparent and more conductive.

According to Jason Heikenfeld, an associate professor at the University of Cincinnati, the newly enhanced PEDOT:PSS might not be superior to ITO in terms of performance, but it’s still good enough to do the job.

Joseph Shinar, one of the Ames scientists leading the project, added that PEDOT:PSS may actually have an advantage over ITO as it possesses a favourable micro-optical cavity effect that makes it more energy efficient.

The research paper explaining all of this is pretty technical, but from what we can gather it looks like being exceptionally good news for anyone hoping to get their hands on an OLED television at some point in the near future.

There’s little doubt that the research, if proved to be commercially viable, would have a significant impact on OLED’s commercial development. With PEDOT:PPS offering an estimated 40% improvement in efficiency over ITO anodes and being much more widely available, production costs would nosedive quite spectacularly, making the technology affordable for the average consumer much faster than anyone had hoped for.

But that’s not all, for there’s a bonus in all of this too. Unlike with indium, which is extremely brittle and therefore quite unsuitable for flexible displays, another of PEDOT:PPS’s attributes is its flexibility, meaning that the goal of flexible HDTV sets could also finally be realised.

Source: IEEE Spectrum magazine