Proceedings Article | 8 October 2005
KEYWORDS: Organic light emitting diodes, OLED lighting, Light sources and illumination, Solid state lighting, Lamps, External quantum efficiency, Quantum efficiency, Integrating spheres, Temperature metrology, Phosphorescent organic light-emitting diodes
A 6"x6" white lighting panel consisting of red, green and blue colored stripes of OLEDs emits >100 lm of optical power and has a maximum energy efficacy of 30 lm/W. Each colored stripe contains 7 serially connected OLEDs having an area of 1.37 cm2, and there are 4 stripes per color, so there is a total of 84 devices. The external quantum efficiency of the red and blue OLEDs exceeds 20% and the blue OLED efficiency exceeds 5% when operated above 100 nits. Such high quantum efficiencies are achieved with an OLED architecture consisting of electrophosphorescent dopants, and at least four organic thin films layers: a hole injection layer, a hole transport layer, an emissive layer, a blocking layer, and an electron transport layer. The color coordinates of the panel can be varied between the constituent red, green, and blue color component coordinates of (0.14, 0.17), (0.31, 0.64), and (0.62, 0.38), respectively, by adjusting the intensity of each primary colors. Panel power efficiencies were measured at correlated color temperatures between 2,900 K and 5,700K, and the color rendering index was >80 in all cases because of the broad spectral output of the combined colors.