Organic light-emitting display

An organic light-emitting display, comprising:

• a first pixel area disposed on a substrate and configured to emit a light of a first color;
• a second pixel area disposed on the substrate and configured to emit a light of a second color different from the first color;
• a first anode disposed across from a first cathode;
• a first emitting layer interposed between the first anode and the first cathode, the first emitting layer comprising a fluorescent light-emitting material;
• a first buffer layer interposed between the first emitting layer and the first cathode, the first buffer layer disposed on the first pixel area;
• a second anode disposed across from a second cathode;
• a second emitting layer interposed between the second anode and the second cathode, the second emitting layer comprising a phosphorescent light-emitting material;
• a second buffer layer interposed between the second emitting layer and the second cathode, the second buffer layer disposed on the second pixel area,
• wherein a highest occupied molecular orbital (HOMO) level and a lowest unoccupied molecular orbital (LUMO) level of the first buffer layer are lower than a HOMO level and a LUMO level of the second buffer layer.

An organic light-emitting display, comprising:

• a substrate comprising a first pixel area configured to emit a light of a first color;
• a first anode disposed on the first pixel area of the substrate;
• a first emitting layer disposed on the first anode, the first emitting layer comprising a fluorescent light-emitting material;
• a first buffer layer disposed on the first emitting layer;
• a second buffer layer disposed on the first buffer layer;
• and
• a first cathode disposed on the second buffer layer,
• wherein a highest occupied molecular orbital (HOMO) level and a lowest unoccupied molecular orbital (LUMO) level of the first buffer layer are lower than a HOMO level and a LUMO level of the second buffer layer.