Joint effort produces red phosphorescent OLED devices

By Control Engineering Staff September 14, 2006

Universal Display Corp . and Novaled AG achieved a saturated red Pholed™ phosphorescent OLED device with a luminous efficacy of 15 candelas per ampere (cd/A) and an operating voltage of less than 4 V for a record power efficiency of 12 lumens per Watt (lm/W) at 1,000 candelas per square meter (cd/m2) brightness. The two companies shared their findings in a joint scientific paper presented at the International Society of Optical Engineering (SPIE) Optics and Photonics 2006 conference in San Diego last month.

This milestone was reached by combining Universal Display’s high-efficiency Pholed™ phosphorescent OLED technology and materials with Novaled’s low-voltage conductivity doped Novaled Pin-OLED™ technology and transport materials. Pholed technology offers up to 100% internal quantum efficiency that is as much as four times higher than conventional OLED technology. The company has already achieved performance milestones for its red, green, and blue Pholed systems.

Novaled’s proprietary doping technology and materials offer very-low-voltage OLEDs that can be combined with long operational lifetimes. The two technologies are said to deliver excellent power efficiency based on high internal quantum efficiency and low operating voltage. The red Pin Pholed device with color coordinates of CIE (0.65, 0.35) has a peak external quantum efficiency of 16% and a drive voltage of less than 4 V at 1,000 cd/m2. It also demonstrates projected operational lifetimes of >150,000 hours at an initial luminance of 500 cd/m2 and a luminous efficacy exceeding 15 cd/A.

Universal Display Corp. develops and commercializes OLED technologies and materials for use in the electronic flat panel display, lighting, and other opto-electronic markets. Novaled is engaged in the research, development, and marketing of organic light-emittingdiode (OLED) technologies.

—Edited by Jeanine Katzel , senior editor, Control Engineering