OSRAM Opto Semiconductors today announced the latest achievements in its white OLED project, funded by a $4.65 million grant from the U.S. Department of Energy (DOE). The 2004 DOE grant was issued to research the potential of white OLEDs to save energy in commercial and residential lighting applications. OSRAM's most recent milestone provides a breakthrough in polymer-OLED technology by achieving a record 25 lumens-per-watt (lm/W) of device efficiency.

The company also announced it has developed the first polymer-OLED, "tunable" light source, enabling color tuning and true illumination-design freedom.
"We are very excited to announce our latest DOE achievements. These milestones directly support the DOE's objectives by demonstrating polymer-OLED potential in lighting applications," said Dr. Alfred Felder, OLED Business Unit Head, OSRAM Opto Semiconductors. "By exploring polymer-OLED technology for solid-state lighting applications, we have created a powerful, innovative and desirable solution with confirmed compatibility and scalability over large areas."

The 25 lm/W cool-white-emitting device utilizes a solution-processable, phosphorescent, blue-emitting device in conjunction with an external inorganic phosphor layer. This high 14 lm/W blue color efficiency was achieved by embedding an efficient phosphorescent blue emitter in a polymer host. The OSRAM team has also achieved and demonstrated a 20 lm/W efficient phosphorescent device based on a white-emitting polymer blend. This device employs no external phosphors, and the white emission comes directly from the phosphorescent polymer.