High Stability White SOLEDs (Phase I)

Investigating Organization
Universal Display Corporation

Principal Investigator(s)
Brian W. D'Andrade

Subcontractor
None

Funding Source
Small Business Innovation R&D, Phase I

Award
DOE Share: $100,000

Contract Period
6/20/07 - 3/19/08

Universal Display Corporation proposes to increase the lifetime and power efficacy of WOLEDs by vertically stacking multiple OLEDs in series.  They will develop a white phosphorescent stacked OLED (SOLED) with a lifetime of >5,000 hrs from an initial average luminance of 1,000 cd/m2, and having a warm white color with correlated color temperatures between 2,500 K – 3,500 K and color rendering index >70.

Good WOLED longevity, together with other efficiency-enhancing device developments, will enable the commercialization of organic solid-state lighting sources that attain power efficiency of 150 lm/W at luminance of 1,000 cd/m2 by 2025.  This program takes another significant and critical step toward this efficiency goal by exploring methods to improve the longevity of high brightness WOLEDs by vertically stacking phosphorescent OLED devices in series.

The stacked WOLED architecture enables the use of less current to generate the same amount of luminance as a single WOLED, thereby increasing device lifetime. The reduction in drive current has additional efficiency improving benefits as resistive heating and voltage losses in a lighting panel can effectively be reduced, and the SOLED power efficacy at a given luminance can be higher than a single OLED because OLED efficacy increases with decreasing drive current.

Content dated 2/08