A DOE researcher has achieved a big progress in his research on organic light-emitting diodes (OLED) by partly solving the problem of weak blue diode in white OLED lights.

OLEDs are expected to be a new light source which uses far less power than the traditional incandescent bulbs, while the weaknesses in blue diodes have always been a riddle in the development of white OLED lights. To solve this problem, Asanga Padmaperuma, a research scientist at the Energy Department's Pacific Northwest National Laboratory and technical leader for the lighting program there, has focused on improving the efficiency of blue OLEDs by using novel semiconductive materials to increasing electrical flow in a work presented Sunday at an American Chemical Society meeting.

For white OLED lights, the white light is created either by blending the output of the red, blue and green diodes, or by using a blue diode and filtering out certain wavelengths, with blue diodes of importance in both methods and improving the efficiency and lifetime the key to the perfection of white OLED lights.

The research, which has been funded by DOE's Building Technologies Program and the National Energy Technology Laboratory, has end up with a far more efficient blue diode, said the scientist. "We have achieved the efficiency part," he said. "We have attained the efficiency milestones that we like."

"What's left in this blue OLED is the lifetime metric," He added. A reference to a DOE target is that an OLED device should last 40,000 hours.

"That's going to be my focus in the future -- to take my efficient blue OLED and improve the lifetime," Padmaperuma said.

DOE has set a target to have OLED products available by 2015, with an eye to widespread market adoption by 2025 -- goals which Padmaperuma described as "a reasonable expectation."