White Illumination Sources Using Striped Phosphorescent OLEDs (Phase I)
Universal Display Corp.
Dr. Brian W. D'Andrade
University of Southern California
Small Business Innovation Research
DOE Share: $100,000
7/1/02 - 6/30/03
Based on its research in phosphorescent OLED (PHOLED™) technology, the project team has demonstrated OLEDs that are up to four times more power efficient than previously thought possible. Under two DOE SBIR awards, Universal Display Corp., Princeton University, and the University of Southern California pursued a novel approach to broadband white light generation based on this highly efficient PHOLED technology.
Fabricating a white OLED light source from a series of striped PHOLEDs has the potential to provide a tunable, white lighting source with the requisite performance for CIE and color rendering. So far, the team has demonstrated the feasibility of using this approach for flat-panel displays.
The aim of this Phase 1 study was to demonstrate a striped white light PHOLED light source. UDC has successfully completed and achieved all 3 of the goals set to demonstrate this task. We successfully fabricated 1" striped white PHOLED sources with CIE co-ordinates of (0.32, 0.39) and a CRI of 86 (15% higher than the program goal) and demonstrated a power efficiency of 5.5 Lm/W at 800 cd/m2 exceeding the program goal by 10%. Finally a preliminary study was made to determine the minimum stripe resolution necessary for a 3 color white light source to appear uniform to the eye. This work demonstrates the feasibility of the striped PHOLED color source approach to enable next generation flat panel general illumination sources.
Recently, UDC was awarded a phase II contract to continue the development of a general illumination source using PHOLEDs. In Phase II, UDC plans to demonstrate a white PHOLED light source on a glass substrate with an efficiency of 20 lm/W at a luminance of 800 cd/m2. Additionally, UDC plans the demonstration and delivery of 6"x6" prototype lighting panels based on PHOLED lighting sources, based on tiling four 3"x3" sub-panels. This will involve the mechanical and electrical design of the panels, with particular focus on the manner in which individual light sources are interconnected, design and fabrication of drive electronics, mask layout for the component sub-panels, along with their fabrication and characterization.
The successful completion of this Phase 2 work will significantly accelerate the use of PHOLED devices as commercial lighting sources. The integration of these parallel efforts with the strategies developed in this proposal will enable PHOLEDs to become a viable source of general illumination.