Organic light emitting diode and organic light emitting diode display device comprising the same

1. An organic light emitting element, comprising:

a first electrode;

a first organic layer on the first electrode and a second organic layer on the first organic layer, a mixed layer being present between the first organic layer and the second organic layer; and

a second electrode on the second organic layer, wherein:

a gap between a highest occupied molecular orbital (HOMO) energy level of the first organic layer and a lowest unoccupied molecular orbital (LUMO) energy level of the second organic layer is in a range from about 1.35 eV to about 1.70 eV, and

the mixed layer emits light having a wavelength in a range from about 740 nm to about 950 nm by exciplex.

2. The organic light emitting element as claimed in claim 1 , wherein the first organic layer, the second organic layer, and the mixed layer do not include a dopant.

3. The organic light emitting element as claimed in claim 1 , wherein:

the first organic layer consists essentially of a first organic material,

the second organic layer consists essentially of a second organic material,

the mixed layer consists essentially of the first and second organic materials,

the mixed layer has a concentration gradient so that a concentration value of the second organic material increases along a direction from the first organic layer toward the second organic layer and a concentration value of the first organic material increases along a direction from the second organic layer toward the first organic layer.

4. The organic light emitting element as claimed in claim 1 , wherein the first organic layer is a hole transport layer.

5. The organic light emitting element as claimed in claim 1 , wherein the first organic layer is a resonance auxiliary layer.

6. The organic light emitting element as claimed in claim 1 , further comprising a third organic layer between the first electrode and the first organic layer.

7. The organic light emitting element as claimed in claim 6 , wherein the highest occupied molecular orbital energy level of the first organic layer is lower than a highest occupied molecular orbital energy level of the third organic layer.

8. The organic light emitting element as claimed in claim 1 , wherein the second organic layer is an electron transport layer.

9. The organic light emitting element as claimed in claim 1 , further comprising a fourth organic layer between the second organic layer and the second electrode.

10. The organic light emitting element as claimed in claim 9 , wherein the lowest unoccupied molecular orbital energy level of the second organic layer is higher than a lowest unoccupied molecular orbital energy level of the fourth organic layer.

11. An organic light emitting display device, comprising:

a substrate;

a driving circuit portion on the substrate; and

an organic light emitting element on the driving circuit portion,

wherein the organic light emitting element comprises:

a first electrode;

a first organic layer on the first electrode and a second organic layer on the first organic layer, a mixed layer being present between the first organic layer and the second organic layer; and

a second electrode on the second organic layer, wherein:

a gap between a highest occupied molecular orbital energy level of the first organic layer and a lowest unoccupied molecular orbital energy level of the second organic layer is in a range from about 1.35 eV to about 1.70 eV, and

the mixed layer emits light having a wavelength in a range from about 740 nm to about 950 nm by exciplex.

12. The organic light emitting display device as claimed in claim 11 , wherein the first organic layer, the second organic layer, and the mixed layer do not include a dopant.

13. The organic light emitting display device as claimed in claim 11 , wherein:

the first organic layer consists essentially of a first organic material,

the second organic layer consists essentially of a second organic material,

the mixed layer consists essentially of the first and second organic materials,

the mixed layer has a concentration gradient so that a concentration value of the second organic material increases along a direction from the first organic layer toward the second organic layer and a concentration value of the first organic material increases along a direction from the second organic layer toward the first organic layer.

14. The organic light emitting display device as claimed in claim 11 , further comprising a third organic layer between the first electrode and the first organic layer.

15. The organic light emitting display device as claimed in claim 14 , wherein the highest occupied molecular orbital energy level of the first organic layer is lower than a highest occupied molecular orbital energy level of the third organic layer.

16. The organic light emitting display device as claimed in claim 11 , further comprising a fourth organic layer between the second organic layer and the second electrode.

17. The organic light emitting display device as claimed in claim 16 , wherein the lowest unoccupied molecular orbital energy level of the second organic layer is higher than a lowest unoccupied molecular orbital energy level of the fourth organic layer.

18. The organic light emitting display device as claimed in claim 11 , wherein the driving circuit portion comprises:

a gate line on the substrate;

a data line crossing the gate line; and

a thin film transistor connected to the gate line and the data line.

19. The organic light emitting display device as claimed in claim 11 , further comprising a thin film encapsulation layer on the second electrode,

wherein the thin film encapsulation layer comprises:

at least one inorganic layer; and

at least one organic layer arranged alternately with the at least one inorganic layer.