Realizing an efficient warm white organic light-emitting device possessing excellent color-stability and color rendering index

摘要

We were successful in realizing an efficient warm white organic light-emitting device simultaneously exhibiting extreme color-stability and high color rendering index (CRI) just by precisely confining the recombination zone and fully utilizing the energy transfer between excitons. The warm white OLED presents maximum efficiencies of 21.4 cd/A, 25.8 lm/W and still remains at high efficiencies of 17.7 cd/A, 15.6 lm/W at the luminance of 1000 cd/m(2). As the operating current density increases from 10 mA/cm(2) to 60 mA/cm(2), the variations in Commission Internationale de l'Eclairage (CIE) coordinates are only (0.004, 0.007) while the general CRI (R-a) maintains at 80 approximately and the special CRI R-9 is higher than 20. What is more, the Duv satisfies the criteria for CRI measurements and the gamut area index (GAI) ensures the vividness of the illuminated objects, as renders the fabricated white OLED a promising candidate for high-quality solid-state lighting application. We also studied the origin of the quite slight color variations for the warm white OLED.