Stacked white organic light emitting devices consisting of separate red, green, and blue elements

Abstract

We demonstrate a white organic light-emitting device where individual red, green, and blue (R, G, and B) phosphorescent organic light-emitting devices are vertically stacked and electrically interconnected by a compound ${\text{MoO}}_3/\text{Li}$ -doped charge generation layer. For the order of B, G, and R cells positioned relative to the indium tin oxide anode, the device yields a peak total external quantum efficiency (EQE) and power efficiency (PE) of ${\eta }_{\text{ext}}=\left(36\pm 2\right)\%$ at a current density of $J=82\mu \text{A}/{\text{cm}}^2$ and ${\eta }_p=21\pm 1\text{lm}/\text{W}$ at $J=17\mu \text{A}/{\text{cm}}^2$ , respectively. The EQE and PE of the device roll off to $\left(32\pm 2\right)\%$ and $13\pm 1\text{lm}/\text{W}$ at $1000\text{cd}/{\text{m}}^2$ , corresponding to $J=2\text{mA}/{\text{cm}}^2$ . At this luminance, the device shows Commission Internationale de L’Eclairage chromaticity coordinates of (0.45, 0.36) and a color rendering index of 63.