Organic Light-Emitting Device Having Improved Efficiency Characteristics and Organic Light-Emitting Display Apparatus Including the Same

An organic light-emitting device comprising:

• a first electrode,
• a second electrode facing the first electrode,
• a phosphorescent emission layer between the first electrode and the second electrode,
• an electron transportation layer between the phosphorescent emission layer and the second electrode,
• an electron control layer between the phosphorescent emission layer and the electron transportation layer, and
• an electron blocking layer between the phosphorescent emission layer and the first electrode;
• wherein:
• the phosphorescent emission layer comprises a host material and a dopant material, the electron control layer comprises an electron control material and a phosphorescent dopant, and the electron blocking layer comprises an electron blocking material;
• a highest occupied molecular orbital energy level (EHH) of the host material, a lowest unoccupied molecular orbital energy level (ELH) of the host material, a highest occupied molecular orbital energy level (EHC) of the electron control material, a lowest unoccupied molecular orbital energy level (ELC) of the electron control material, and a lowest unoccupied molecular orbital energy level (ELB) of the electron blocking material satisfy |EHH−EHC|≦0.3 eV, |ELH−ELC|≦0.5 eV, and ELB>ELH;
• and
• a thickness of the electron control layer is in a range of about 10 to about 450.