Patent ID: 11950439
Assignee: LG DISPLAY CO., LTD.
Field: nan (nan)
Classification: CPC H | IPC H

Claim 0:
1. A white organic light-emitting device comprising:
a first electrode and a second electrode facing each other; and
a plurality of emission stacks, separated from each other by charge generation layers interposed therebetween, the plurality of emission stacks between the first electrode and the second electrode, wherein:
at least one of the plurality of emission stacks is a phosphorescent stack;
the phosphorescent stack comprises a hole transport layer, and a first phosphorescent layer on the hole transport layer, a second phosphorescent layer on the first phosphorescent layer, and a third phosphorescent layer on the second phosphorescent layer, each of the first phosphorescent layer, the second phosphorescent layer and the third phosphorescent layer to emit light having a longer wavelength than blue light;
the first phosphorescent layer comprises a first red dopant having a highest occupied molecular orbital (HOMO) energy level lower than or equal to a HOMO energy level of the hole transport layer;
the second phosphorescent layer comprises a second red dopant having a HOMO energy level higher than the HOMO energy level of the first red dopant; and
the third phosphorescent layer comprises a third dopant having a luminescence peak at a shorter wavelength than the first red dopant and the second red dopant,
wherein the first phosphorescent layer is in contact with the hole transport layer, and the third phosphorescent layer is in contact with in an electron transport layer in the phosphorescent stack.