Organic light emitting display device

An organic light emitting display device, comprising:

• first and second electrodes on a substrate and facing each other;
• a first stack comprising a hole injection layer, a third hole transport layer, a fourth hole transport layer in direct contact with the third hole transport layer, a third light emitting layer, and a second electron transport layer sequentially stacked on the first electrode;
• a second stack comprising a first hole transport layer, a second hole transport layer in direct contact with the first hole transport layer, at least two light emitting layers, and a first electron transport layer sequentially stacked between the first stack and the second electrode;
• and
• a charge generation layer between the first stack and the second stack, to adjust charge balance between the first stack and the second stack,
• wherein the at least two light emitting layers comprise different respective hosts doped with the same yellow-green dopant in different respective dosages,
• wherein the charge generation layer is in direct contact with the first hole transport layer of the second stack,
• wherein the at least two light emitting layers comprises:
• a first light emitting layer comprising a first host doped with a phosphorescent yellow-phosphorescent green dopant, and
• a second light emitting layer comprising a second host different from the first host doped with the same phosphorescent yellow-phosphorescent green dopant as the first light emitting layer in a different dosage than the first light emitting layer,
• wherein the phosphorescent yellow-phosphorescent green dopant of the first light emitting layer is doped in the first light emitting layer in a dosage of 1% to 10% on the basis of a volume of the first light emitting layer, and
• wherein the phosphorescent yellow-phosphorescent green dopant of the second light emitting layer is doped in the second light emitting layer in a dosage of 10% to 20% on the basis of a volume of the second light emitting layer.

An organic light emitting display device, comprising:

• first and second electrodes on a substrate and facing each other;
• and
• a hole injection layer, a first hole transport layer, a second hole transport layer in direct contact with the first hole transport layer, at least first and second light emitting layers, and an electron transport layer sequentially stacked between the first and second electrodes,
• wherein the first light emitting layer comprises a first host and a second host,
• wherein the second light emitting layer comprises the first host and a third host, and
• wherein the first and second light emitting layers are doped with the same phosphorescent yellow-phosphorescent green dopant in the same dosage.

An organic light emitting display device, comprising:

• first and second electrodes on a substrate and facing each other;
• a first stack comprising a hole injection layer, a third hole transport layer, a fourth hole transport layer in direct contact with the third hole transport layer, a third light emitting layer, and a second electron transport layer sequentially stacked on the first electrode;
• a second stack comprising a first hole transport layer, a second hole transport layer in direct contact with the first hole transport layer, at least two first and second light emitting layers, and a first electron transport layer sequentially stacked between the first stack and the second electrode;
• a first charge generation layer between the first stack and the second stack, to adjust charge balance between the first stack and the second stack;
• a third stack comprising a fifth hole transport layer, a fourth light emitting layer, and a third electron transport layer stacked between the second stack and the second electrode;
• and
• a second charge generation layer between the second stack and the third stack, to adjust charge balance between the second stack and the third stack,
• wherein the first light emitting layer comprises a first host and a second host,
• wherein the second light emitting layer comprises the first host and a third host different from the second host,
• wherein the first and second light emitting layers are doped with the same phosphorescent yellow-phosphorescent green dopant in the same dosage, and
• wherein the charge generation layer is in direct contact with the first hole transport layer of the second stack.