By John McHale
EWING, N.J., 23 May 2008. Engineers at Universal Display Corp., under contract to the U.S. Army have demonstrated flexible OLED – organic light emitting diode – display technology with infrared emission for nighttime use.
The prototype demonstrates the world's first flexible OLED display that incorporates both visible green emission for daytime operation and infrared (IR) emission for use in dark environments, says Janice Mahon, vice president of technology commercialization at Universal Display.
Developed through a two-phase Small Business Innovation Research (SBIR) program with the U.S. Army, this initial prototype was designed to demonstrate capabilities that would enable soldiers in the field to view one display in two modes. Using Universal Display's high-efficiency PHOLED (phosphorescent OLED) technology, the OLED display prototype provides green-color emission for daytime operation, and can be switched to operate in an IR-emission mode, that can only be detected through specialized night-vision goggles, for covert operations. By integrating this onto a flexible substrate, the UDC engineers have achieved a design suitable for portable, rugged, and conformable use day and night in the field.
The active-matrix OLED prototype display based on Universal Display's PHOLED technology, employs visible-emission PHOLED materials as well as new infrared-emitting PHOLED materials and device structures from the Universal Display team in conjunction with its partners at the University of Southern California and the University of Michigan. In addition, this 100 dpi prototype was built on flexible metal foil using low-temperature, poly-silicon backplane technology from Palo Alto Research Center (PARC), and was integrated into a system for the Army by L-3 Communications Display Systems (L-3 Display Systems).
OLEDs offer numerous advantages when compared to today's LCDs, including a more beautiful visual appearance and thinner form factor, Universal Display officials say. In addition, when using Universal Display's PHOLED technology, OLEDs can consume significantly less power than comparable LCDs and conventional fluorescent OLEDs.
One of the novel features of OLEDs is their ability to be built on a flexible substrate, including plastic or metal foil. With the ability to be conformed or routinely flexed, flexible OLEDs may open up a wide range of new display and lighting opportunities. Flexible metal foil offers a number of desirable advantages that include enhanced thermal and mechanical durability, an important characteristic for high-temperature TFT processing, and potentially lower cost, when compared to the flexible plastic substrates that are available today.
The biggest challenge is placing the active matrix TFT onto metal foil, Mahon notes. In recent years Universal Display has expanded its chemical engineering talent pool to 25 in an effort to keep inventing new flexible substrate materials, she adds.
"The new prototype was developed in a wrist-mounted form factor," Mahon says. "This was done through our existing relationship with the Army."
A senior technologist for the Army saw "our pen display, which rolls out" like a scroll from a pen form factor and "he said 'our soldiers should have those!'"
Mahon declined to comment on some of the specific requirements the Army set. "The military has a specific wavelength requirement that I can't discuss, but we were able to meet those requirements."
Universal Display leveraged other going programs for the demonstration including power sources, she adds.
As part of an ongoing effort by the U.S. Army to develop next-generation applications that will enhance field operations for U.S. soldiers, the prototype was delivered to Mr. Raymond Schulze, Chief, Battle Command Interface Branch of the U.S. Army Communication Electronics Research and Development Engineering Center (CERDEC) in Ft. Monmouth, N.J. This project complements flexible display development ongoing at the U.S. Army's Flexible Display Center at Arizona State University, of which Universal Display is a founding member. With further technology development, this display concept may lead to the realization of important, new display functionality that can enhance the communications capabilities of the soldier, company officials say.
"The design and delivery of this display prototype marks another milestone for our high-efficiency, phosphorescent OLED technology, and our work with the U.S. government," says Steven V. Abramson, president and chief executive officer of UDC. The prototype provides further evidence of the benefits that PHOLED technology can provide, he adds.
Last fall Universal Display won a $935,000 contract extension by CERDEC. The extension builds on an existing Small Business Innovative Research (SBIR) Phase III grant with CERDEC for the development of flexible, active-matrix OLED (AMOLED) display technology for demonstration in a prototype wrist-based communications device.
Development efforts under the contract extension focused on combining Universal Display's PHOLED technology with LG.Philips LCD Co., Ltd.'s amorphous-Silicon (a-Si) TFT technology. L-3 Display Systems is responsible for designing and integrating its advanced communications components with the QVGA, full-color, flexible AMOLED display into the prototype wrist-mounted communications device for delivery to CERDEC.
Universal Display was awarded Phase III of the SBIR grant by CERDEC in January 2006. The Company's work with the U.S. Department of Defense also includes flexible AMOLED display development for the U.S. Army Research Laboratories (ARL) as well as the U.S. Navy and U.S. Air Force Research Laboratories.
Universal Display currently owns or has exclusive, co-exclusive or sole license rights with respect to more than 825 issued and pending patents worldwide. They do not manufacture displays but license technology they develop.
For more information, visit www.universaldisplay.com.
