Patent ID: 8525160

Claim:
An organic light-emitting device, comprising: a substrate; a first electrode; a second electrode facing the first electrode; an emission layer between the first electrode and the second electrode; a first electron transport layer between the second electrode and the emission layer, the first electron transport layer including a first electron transporting material; a second electron transport layer between the second electrode and the first electron transport layer, the second electron transport layer including a second electron transporting material; a third electron transport layer between the second electrode and the second electron transport layer, the third electron transport layer including a third electron transporting material and a fourth electron transporting material; and a hole transport layer between the first electrode and the emission layer, wherein: the first electron transporting material has an electron mobility smaller than an electron mobility of the second electron transporting material at an electric field of 800 to 1000 V/cm, the second electron transporting material and the third electron transporting material each independently have an electron mobility of about 10 −8 to about 10 −3 cm 2 /V·s at an electric field of 800 to 1000 V/cm, and the third electron transport layer has an electron injection barrier of about 0.2 eV or less at an interface between the third electron transport layer and the second electrode.