Patent ID: 8901814

Claim:
A light-emitting element comprising: a first electrode; a second electrode; a first layer between the first electrode and the second electrode, the first layer including a first substance dispersed in a first host material; a second layer between the second electrode and the first layer, the second layer including a second substance dispersed in a second host material; a third layer between the first layer and the second layer, the third layer containing a first material with a carrier transporting property; a fourth layer between the first electrode and the first layer, the fourth layer containing a second material with a carrier transporting property; a first carrier transporting layer between the first electrode and the fourth layer; and a second carrier transporting layer between the second electrode and the second layer, wherein the third layer is in direct contact with the first layer and the second layer, wherein the first material is the same as the first host material, and wherein a band gap of the second material is bigger than a band gap of a substance included in the first carrier transporting layer.