Patent ID: 8653553

Claim:
A light-emitting element comprising: a first electrode; a first light-emitting layer over the first electrode comprising: a first phosphorescent compound; and a first host material; a second light-emitting layer over the first light-emitting layer comprising: a second phosphorescent compound; and a second host material; a third light-emitting layer over the second light-emitting layer comprising: a third phosphorescent compound; and a third host material; and a second electrode over the third light-emitting layer, wherein the first phosphorescent compound emits blue light, wherein ε(λ)λ 4 of the second phosphorescent compound has a peak within a wavelength range of 440 nm to 520 nm, wherein the second phosphorescent compound emits light with a wavelength longer than a wavelength of the light emitted from the first phosphorescent compound, wherein ε(λ)λ 4 of the third phosphorescent compound has a peak within a wavelength range of 520 nm to 600 nm, wherein the third phosphorescent compound emits light with a wavelength longer than the wavelength of the light emitted from the second phosphorescent compound, wherein λ denotes a wavelength, and wherein ε(λ) denotes a molar absorption coefficient at the wavelength λ.