High-efficiency, very-high color rendering white organic light-emitting diode with a high triplet interlayer

This study reports the fabrication of a highly efficient, very high color-rendering index (CRI) white organic light-emitting diode (OLED) using five organic dyes doped into two different phosphorescent and fluorescent emissive layers separated by a high triplet-energy interlayer. The resulting white OLED achieves a 93 CRI with a power efficiency of 23.3 lm W-1 at 100 cd m(-2), or 14.3 lm W-1 at 1000 cd m(-2). This high CRI is attributable to the five dyes employed in this design, which together emit a relatively wide spectrum that nearly covers the entire range of visible light. At the proper thickness, the interlayer enables the device to balance the distribution of carriers in the two emissive zones and achieve a maximum power efficiency while maintaining high CRI.