Patent ID: 8558224

Claim:
An organic light-emitting diode comprising: an anode and a cathode which are arranged apart from each other; a red and green emissive layer on the anode side and a blue emissive layer on the cathode side, which are arranged apart from each other between the anode and the cathode; and a spacer layer which is inserted between the red and green emissive layer and the blue emissive layer, and consists of a hole transport material which prevents energy transfer from the blue emissive layer to the red and green emissive layer, where the red and green emissive layer contains a host material having hole transportability, a red phosphorescent emitting dopant, and a green phosphorescent emitting dopant, and the blue emissive layer contains a host material having electron transportability and a blue fluorescent emitting dopant, the red and green emissive layer contains 20 to 40 wt % of the red phosphorescent emitting dopant and the green phosphorescent emitting dopant in combination, a HOMO of the red phosphorescent emitting dopant and the green phosphorescent emitting dopant and a HOMO of the hole transport material in the spacer layer have nearly equal energy levels, a HOMO-LUMO energy gap of the hole transport material in the spacer layer is larger than a HOMO-LUMO energy gap of the blue fluorescent emitting dopant, and a thickness of the spacer layer is 3 to 5 nm, and a T1 energy of the blue fluorescent emitting dopant is lower than a T1 energy of the hole transport material of the spacer layer.