| abstract |
An organic light emitting device is disclosed whose emissive layer has a host material, a first emissive dopant, and a second dopant. The second dopant is an excited energy state managing dopant provided in an amount between 2-10 vol. % of the emissive layer and has a lowest triplet state energy level, T M , that is higher than a lowest triplet state energy levels, T 1 , of both the host and the first dopant and lower than the multiply-excited energy level, T*, of the first dopant. |