Jun 18, 2012

Dupont published some new OLED material specification, you can see them in the photo below. The lifetime (LT50) of their Blue fluorescent material is now over 33,000 hours (the the 0.14c0.13 blue, anyway) - which they say is good enough for OLED TVs. Their solution-processed materials are now more efficient than their evaporated-materials, but lifetime is probably lower (it's a bit hard to know since they only publish LT95 for those materials).

I had an interesting discussion with a Dupont employee involved in their OLED program. In January 2012 it was reported that the company is building a $30 million pilot production line for OLED TV displays using their new nozzle printing technology. It turns out that the report wasn't accurate - the facility that DuPont is building is a material production facility. They have no intention to start producing displays...

A while back UDC's Sid Rosenblatt said that Samsung is Dupont's asian Nozzle-printing licensee. I didn't manage to get a confirmation for that though.

Dupont does intend to provide a whole stack of OLED materials. Currently they offer HIL, HTL, EML (emissive) and ETL materials.


The lifetimes from the chart are somehow not comparable. It does not say, what the initial brightness was and therefore also the scaling factor from LT95 to LT50 is not really clear.

500.000 hrs lifetime are some 10 years of measurement, so in case they not have the OLED thing cooking under cover since WWII, they have used accelerated lifetime testing.


Also: HIL, HTL, EML, and ETL should make a complete OLED stack (except anode and cathode), especially when they are in the wet processing business (to print 3-4 layers onto each other is a tough job by itself).

As long as they find a way to keep the color balance accurate because of the different wear of colors, I really don't care much about the lifetime. Anything above 10,000 is acceptable once prices have reached a level of today's LCDs. Because that's about 8 hours per day for three years.

And anything around 20,000 would even be alright at a higher price. That used to be roughly the lifetime of CRTs and I thought that was just fine. After 6 years (if you use your display a lot), displays are going to be a lot cheaper anyway and getting a replacement won't be a big deal.

3 years lifetime may be acceptable for mobile phones displays, but I strongly doubt it customers will accept in on a broader scale for TV displays. I really like those 55" OLED displays that have been presented at SID, but I know for sure that I wouldn't buy them with only a 3 year lifetime.

Also you have to keep in mind that some markets (e.g. the EU) have a legal 2 year warranty period and as a company you have to make sure that the percentage of failures during warranty remains as low as possible. Not sure 10,000 hrs would be enough here either.

Kyulux - Hyperfluoresence OLED emittersKyulux - Hyperfluoresence OLED emitters