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Blue color News
Researchers from the University of Michigan developed a new phosphorescent OLED (PHOLED) emitter that extends the lifetime by a factor of 10. Researchers have been trying to develop an efficient, long-lasting blue PHOLED emitter for years now, and this may be the breakthrough everybody's been waiting for.
OLED makers SDC and LGD already use red and green PHOLED emitter materials in their OLED panels. While phosphorescent emitters do not last as long as fluorescent emitters, they are much more efficient. All commercial OLED displays currently use a fluorescent blue emitter as the best PHOLED blue to date only lasted for a few hundred hours.
Updated: This story had some inaccuracies and is now updated with new information from First-O-Lite
China's First-O-Lite says they developed an efficient (111.7 lm/W at 1,000 cd/m2) hybrid OLED lighting device (2 cm2). This is a hybrid device that uses a fluorescent blue emitter along with red and blue phosphorescent emitters. The company says that this is probably the most efficient hybrid OLED device ever produced that can meet the Energy Star color requirements.
First-O-Lite has established a volume production fab and will soon start producing OLED panels. These will feature over 55 lm/W (at 3,000 cd/m2) and will use the company's external light extraction technology.
BASF hopes to release a long lasting phosphorescent blue emitter in 2014, to open an OLED lab in Korea
BASF has been working on a blue phosphorescent OLED emitter for quite some time - in fact the company says they have started developing an iridium-based blue PHOLED as early in 2003. Now Karl Hahn, a senior VP at BASF, says that the company will be ready to launch a commercial blue phosphorescent emitter by the end of 2014 aimed towards OLED lighting panels.
During the same presentation, Karl Hahn said that BASF plans to open a new OLED display focused laboratory in Korea during 2014.
French site Lesnumeriques posted an article on Samsung's KN55S9C curved OLED TV, in which they include a macro-photo showing the TV's sub pixels up close:
As you can see, the blue subpixels are bigger than the red and green ones (about twice as large). This was designed this way because the blue OLED has the lowest lifetime - if it is bigger then you can lower the brightness and so conserve lifetime. We've seen many OLED displays with differently-sized subpixels - including PenTile ones and the rather unique display used in the Note 2.
Cynora is a German startup established in 2003 that developed copper-based OLED emitter systems. In October 2012 the company unveiled a mostly-solution-based flexible OLED prototype, developed in collaboration with InnovationLab. Last month Germany’s BMBF launched the cyCESH project which aims to develop soluble (printable) materials for low-cost high efficiency OLED lighting devices. Cynora is the leader of the consortium in this €6 million project, together with Novaled and the University of Regensburg.
Cynora's technology is interesting and the company's CEO Dr. Tobias Grab and the company's Business Development manager, Dr. Mathias Mydlak, were kind enough to provide the information for this article explaining the company's technology.
The US Department of Energy (DoE) announced the eligble topics for the FY 2014 SBIR and STTR funding. There are two topics involving OLED lighting efficiency. The first is the development of OLED materials and structures that will lead to the production and commercialization of a highly efficient, stable white OLED device. The DOE specifically mentions the development of highly efficient, blue emitter materials and hosts.
The second topic is the development of methods of manufacturing either OLED pixels or panels or devices. The DoE is also interested in system level integration solutions that would accelerate OLED devices into niche markets. If you want to apply, you will have to send the application by October 15. The DoE will formally announce the opportunities on August 12.
A few days ago we reported about new research from Dankook University (DKU) that developed the world's most efficient blue OLED emitter. Today I talked with Professor Lee Jun Yeob, who's in charge of that research at DKU, and he explained his research further.
It turns out that in that particular research, they developed a new host material for blue OLEDs, and not a new emitter. The 30.1% efficiency they quote is external quantum efficiency. The blue emitter itself is a phosphorescent OLED - a common emitter known as FIrpic (Iridium based). Universal Display were not involved in this work.