Display device

A display device comprising:

• a first light-emitting device;
• a second light-emitting device;
• and
• a third light-emitting device,
• wherein the first light-emitting device comprises a first anode, a first cathode, a first light-emitting layer, and a first hole-blocking layer, the first light-emitting layer and the first hole-blocking layer being between the first anode and the first cathode,
• wherein the first hole-blocking layer is between the first light-emitting layer and the first cathode,
• wherein the second light-emitting device comprises a second anode, a second cathode, and a second light-emitting layer, the second light-emitting layer being between the second anode and the second cathode,
• wherein the third light-emitting device comprises a third anode, a third cathode, a third light-emitting layer, and a fourth light-emitting layer, the third light-emitting layer and the fourth light-emitting layer being between the third anode and the third cathode,
• wherein the fourth light-emitting layer is between the third light-emitting layer and the third cathode,
• wherein a color of light emitted from the first light-emitting device, a color of light emitted from the second light-emitting device, and a color of light emitted from the third light-emitting device are different from each other,
• wherein the first light-emitting layer and the third light-emitting layer comprise a first light-emitting substance and a hole-transport material,
• wherein the second light-emitting layer and the fourth light-emitting layer comprise a second light-emitting substance, and
• wherein a peak wavelength of an emission spectrum of the first light-emitting substance and a peak wavelength of an emission spectrum of the second light-emitting substance are different from each other.

A display device comprising:

• a first light-emitting device;
• a second light-emitting device;
• and
• a third light-emitting device,
• wherein the first light-emitting device comprises a first anode, a first cathode, a first light-emitting layer, a second light-emitting layer, and a first intermediate layer, the first light-emitting layer, the second light-emitting layer, and the first intermediate layer being between the first anode and the first cathode,
• wherein the first intermediate layer is between the first light-emitting layer and the second light-emitting layer,
• wherein the second light-emitting device comprises a second anode, a second cathode, a third light-emitting layer, a fourth light-emitting layer, and a second intermediate layer, the third light-emitting layer, the fourth light-emitting layer, and the second intermediate layer being between the second anode and the second cathode,
• wherein the second intermediate layer is between the third light-emitting layer and the fourth light-emitting layer,
• wherein the third light-emitting device comprises a third anode, a third cathode, a fifth light-emitting layer, a sixth light-emitting layer, and a third intermediate layer, the fifth light-emitting layer, the sixth light-emitting layer, and the third intermediate layer being between the third anode and the third cathode,
• wherein the third intermediate layer is between the fifth light-emitting layer and the sixth light-emitting layer,
• wherein a color of light emitted from the first light-emitting device, a color of light emitted from the second light-emitting device, and a color of light emitted from the third light-emitting device are different from each other,
• wherein the first light-emitting layer, the second light-emitting layer, and the fifth light-emitting layer comprise a first light-emitting substance,
• wherein the third light-emitting layer, the fourth light-emitting layer, and the sixth light-emitting layer comprise a second light-emitting substance, and
• wherein a peak wavelength of an emission spectrum of the first light-emitting substance and a peak wavelength of an emission spectrum of the second light-emitting substance are different from each other.