Organic light emitting device

1. An organic light-emitting device, comprising:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein:

the emission layer includes a plurality of sub-emission layers to emit light having different wavelength ranges, at least portions of the plurality of sub-emission layers do not overlap one another, at least one of the plurality of sub-emission layers include:

a mixed hole-transporting host and electron-transporting host which form an exciplex; and

a light-emitting dopant; and

a triplet energy of the exciplex is equal to or greater than triplet energies of the light-emitting dopant.

2. The organic light-emitting device as claimed in claim 1 , wherein the plurality of sub-emission layers include:

a first sub-emission layer including the hole-transporting host and the electron-transporting host, and a first color light-emitting dopant; and

a second sub-emission layer including the hole-transporting host and the electron-transporting host, and a second color light-emitting dopant; and

wherein the first sub-emission layer emits longer wavelength light than the second sub-emission layer.

3. The organic light-emitting device as claimed in claim 2 , wherein:

the plurality of sub-emission layers further include a third sub-emission layer that includes the hole-transporting host and the electron-transporting host, and a third color light-emitting dopant, and

wherein the third sub-emission layer emits shorter wavelength light than the first and second sub-emission layers.

4. The organic light-emitting device as claimed in claim 1 , wherein the triplet energy of the exciplex is about 2.4 eV to about 3.0 eV.

5. The organic light-emitting device as claimed in claim 1 , wherein a difference between a lowest unoccupied molecular orbital (LUMO) energy level of the hole-transporting host and a LUMO energy level of the electron-transporting host is about 0.2 eV or more.

6. The organic light-emitting device as claimed in claim 1 , wherein a difference between a highest occupied molecular orbital (HOMO) energy level of the hole-transporting host and a HOMO energy level of the electron-transporting host is about 0.2 eV or more.

7. The organic light-emitting device as claimed in claim 1 , wherein a weight ratio of the hole-transporting host to the electron-transporting host is about 80:20 to about 20:80.

8. The organic light-emitting device as claimed in claim 1 , wherein the plurality of sub-emission layers include:

a first sub-emission layer including a red light-emitting dopant;

a second sub-emission layer including a green light-emitting dopant; and

a third sub-emission layer including a blue light-emitting dopant;

wherein at least one of the first sub-emission layer and the second sub-emission layer include the hole-transporting host and the electron-transporting host.

9. The organic light-emitting device as claimed in claim 8 , wherein the red light-emitting dopant and green light-emitting dopant emit phosphorescent light.

10. The organic light-emitting device as claimed in claim 8 , wherein the first to third sub-emission layers each includes the hole-transporting host and the electron-transporting host, and

wherein the red light-emitting dopant and green light-emitting dopant emit phosphorescent light and the blue light-emitting dopant emits thermally activated delayed fluorescence (TADF) light.

11. The organic light-emitting device as claimed in claim 8 , wherein a thickness of the first sub-emission layer is thicker than the second sub-emission layer, and a thickness of the second sub-emission layer is thicker than the third sub-emission layer.

12. The organic light-emitting device as claimed in claim 8 , wherein the emission layer further includes an auxiliary layer that disposed between the hole control layer and the plurality of sub-emission layers.

13. The organic light-emitting device as claimed in claim 8 , wherein the auxiliary layer includes:

a first auxiliary layer disposed between the hole control layer and the first sub-emission layer;

a second auxiliary layer disposed between the hole control layer and the second sub-emission layer; and

a third auxiliary layer disposed between the hole control layer and the third sub-emission layer; and

wherein a thickness of the first auxiliary layer is thicker than the second auxiliary layer, and a thickness of the second auxiliary layer is thicker than the third auxiliary layer.

14. An organic light-emitting device, comprising:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein:

the emission layer includes:

a first sub-emission layer including a red light-emitting dopant;

a second sub-emission layer including a green light-emitting dopant; and

a third sub-emission layer including a blue light-emitting dopant;

at least portions of the first to third sub-emission layers do not overlap one another,

at least one of the first sub-emission layer and the second sub-emission layer includes a mixed hole-transporting host and electron-transporting host which form an exciplex, and

a triplet energy of the exciplex is equal to or greater than triplet energies of the red light-emitting dopant and the green light-emitting dopant.

15. The organic light-emitting device as claimed in claim 14 , wherein:

the third sub-emission layer includes the hole-transporting host and the electron-transporting host, and

a difference between a triplet energy level of the exciplex and a singlet energy level of the blue light-emitting dopant is about −0.1 eV to about 0.1 eV.