Article Abstracts | September 2007
The complete article appears in the September 2007 issue of Photonics Spectra. If you do not have a copy of this issue,
e-mail us a request. Be sure to include your street address or fax number.
The Making of a Flexible Active-Matrix OLED Display
Material, substrate and packaging are key components in making a flexible
active-matrix OLED display.
by Rui-Qing Ma, Mike Hack and Julie J. Brown, Universal Display Corp.
Imagine a display as thin as paper that can be rolled into a small tube, wrapped around objects such as a cell phone, dropped on the ground or even hammered and yet still function. In addition, the exhibit shows the highly pure color and crisp high-speed motion pictures that can be viewed from all directions with the same high quality while consuming very little power. Such displays are close to being a reality, thanks to organic LEDs (OLEDs).
Phosphorescent OLEDs
The first efficient small-molecule OLED devices were invented in the 1980s by Tang et al. from Eastman Kodak of Rochester, N.Y. In these fluorescent small-molecule OLEDs, light emission occurs from singlet excitons. The internal quantum efficiency is limited to approximately 25 percent because about 75 percent of the excitons are formed in the triplet state. Based on the early pioneering work by Stephen R. Forrest at Princeton University in New Jersey and by Mark E. Thompson at the University of Southern California, Los Angeles, researchers at Universal Display Corp. of Ewing, N.J., are developing the next generation of OLEDs, which are high-efficiency phosphorescent devices...
Start a discussion on this article or any photonics topic in the Photonics.com Community Forum