ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Vertical stacking of organic light emitting devices (OLEDs) that emit the three primary colors is shown to be a means for achieving efficient and bright full-color displays. In Paper I, we addressed stacked OLED (SOLED) design and fabrication principles to optimize emission colors, operating voltage, and efficiency. Here, we present results on two different (metal-containing and metal-free cathode) SOLED structures that exhibit performance suitable for many full-color display applications. The operating voltages at 10 mA/cm2 (corresponding to video display brightnesses) are 6.8, 8.5, and 12.1 V for the red (R), green (G), and blue (B) elements of the metal-containing SOLED, respectively. The respective subpixel luminous efficiencies are 0.53, 1.44, and 1.52 cd/A, and the Commission Internationale de L'Éclairage (CIE) chromaticity coordinates are (0.72, 0.28), (0.42, 0.56), and (0.20, 0.22). In the high transparency metal-free SOLED, an insulating layer was inserted between the two upper subpixels to allow for independent grounding of all color emitters in the stack. At operating voltages of 12–14 V, video display brightnesses were achieved with luminous efficiencies of 0.35, 1.36, and 1.05 cd/A for the R, G, and B subpixels, respectively. The respective CIE coordinates for R, G, and B emissions are (0.72, 0.28), (0.26, 0.63), and (0.17, 0.28) in the normal viewing direction, shifting inperceptibly as the viewing angle is increased to as large as 60°. Finally, we discuss addressing schemes of SOLED displays, and compare them with other strategies for achieving full-color, OLED-based displays. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.371428
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