Patent attributes
A light-emitting element includes a first electrode; a first light-emitting layer over the first electrode, containing a first phosphorescent compound and a first host material; a second light-emitting layer over the first light-emitting layer, containing a second phosphorescent compound and a second host material; a third light-emitting layer over the second light-emitting layer, containing a third phosphorescent compound and a third host material; and a second electrode over the third light-emitting layer. Between peaks of emission spectra of the first, second, and third phosphorescent compounds, the peak of the emission spectrum of the second phosphorescent compound is on the longest wavelength side and that of the emission spectrum of the third phosphorescent compound is on the shortest wavelength side. The third host material has higher triplet excitation energy than the first host material and the second host material.
