OLEDs, the Good News and the Bad News

A lot of British jokes start with the introduction “I’ve got some good news, and some bad news”. Many of them are cruel or politically incorrect, so I won’t repeat them here, but it seemed that our stories this week in OLED seemed to follow that format. I’ll follow the form of the jokes, so we’ll start with the good news.

The LG commitment to a massive flexible OLED investment is a big endorsement of the technology. Samsung is doing very well with its Edge phones and clearly smartphone designers will want to exploit the opportunities to create new form factors. Issues of robustness and protection of the display from the environment (and the user) mean that, at the moment, rigid glass covers stop really flexible designs and act as the limit on design. The Edge phones are not really flexible, the display is used as though it was ‘conformable’ – that is, bendable at the point at the point of device production, but then fixed.

Clearly LG Display has had indications from its customer base that there will be demand for the products of its new fab and this is likely to include the smartphone business of its ‘captive’ customer as well as companies that want a second source or alternative supplier to Samsung. I highlight smartphones, but automotive is also a good potential early market for flexible displays (although concerns about a range of issues including image burn will be a challenge). I’m less convinced about a mass market for larger flexible displays than about tablet size, but it’s possible that new applications will develop. I certainly see a potential market for curved monitors and I’ve written before about ‘flip’ smartphones and tri-fold tablets, which could re-vitalise the smart device market.

Now the bad news. Samsung is not going to continue with its large transparent OLED plans. I must say that the only reason that I thought Samsung was really developing this was to use it as a very small market that it could use to develop its large OLED manufacturing. That has proved a challenge for the company. As I’ve said many times over the years, when Samsung announced at SID that it was going to go into the large OLED business based on RGB pixels and with an LTPS substrate, I was amazed that it was going to try something so difficult. On the other hand, the difficulty was part of the appeal as the company tried to stay well ahead of the Chinese LCD makers.

The transparent display was a technology tour de force, really, but suffered a lot from restrictions. Brightness is not really high enough for the kind of public display applications that might have wanted the technology, and operating conditions were very restricted, as we have reported, because of image sticking among other things. I had assumed that Samsung was really trying to head to a new kind of application such as window displays – AR windscreens for cars, perhaps, one day? However, as we reported a few weeks ago, the reality is that the transistors in current transparent displays act optically to mean that they stop you being able to clearly see objects that are at a distance from the display. That’s why the demos you’ve seen have always been based on objects being visible in small spaces behind the display.

So, good news for small and flexible OLEDs and bad news for big flat OLEDs.