Display device with optical pattern layer

1. A display device comprising:

a light emitting element layer,

an optical pattern layer disposed on the light emitting element layer, the optical pattern layer comprising:

first pattern layer having a first refractive index, the first pattern layer comprising:

a base part; and

protruding parts protruded from the base part and spaced apart from each other; and

a second pattern layer disposed on the first pattern layer and having a second refractive index less than the first refractive index, and

an optical member disposed between the light emitting element layer and the optical pattern layer, wherein

the first pattern layer is disposed directly above the optical member,

the second pattern layer is a planarization layer and is filled between the protruding parts, and

the optical member comprises at least one of a polarizing layer and a color filter layer.

2. The display device of claim 1 , wherein the light emitting element layer comprises:

a first electrode;

a second electrode facing the first electrode;

a light emitting layer disposed between the first electrode and the second electrode and comprising an organic electroluminescent material or a quantum dot; and

an encapsulation layer disposed on the second electrode,

wherein the first electrode is a reflective electrode, and the second electrode is a transmissive electrode or a transflective electrode.

3. The display device of claim 1 , wherein each of the protruding parts has a cylindrical or prismatic shape protruding from the base part.

4. The display device of claim 1 , wherein each of the protruding parts comprises:

a bottom surface adjacent to the base part;

a ceiling surface facing the bottom surface; and

a side surface extended between the bottom surface and the ceiling surface,

wherein an inclination angle of the side surface with respect to the bottom surface on a cross section perpendicular to the base part is in a range from about 70° to about 90°.

5. The display device of claim 4 , wherein the bottom surface has a width in a range from about 4 μm to about 10 μm on the cross section perpendicular to the base part.

6. The display device of claim 4 , wherein:

each of the protruding parts has a height in a range from about 7 μm to about 15 μm and the height is a minimum spaced distance between the bottom surface and the ceiling surface.

7. The display device of claim 4 , wherein:

the protruding parts comprise a first protruding part and a second protruding part, which are adjacent to each other, and

a minimum spaced distance between the bottom surface of the first protruding part and the bottom surface of the second protruding part is in a range from about 4 μm to about 10 μm.

8. The display device of claim 4 , wherein the bottom surface has a width that is different from a width of the ceiling surface.

9. The display device of claim 1 , wherein:

the first refractive index is from about 1.5 to about 1.7, and

a difference between the first refractive index and the second refractive index is equal to or greater than about 0.1.

10. A display device comprising:

a light emitting element layer comprising:

a first electrode;

a second electrode facing the first electrode; and

a light emitting layer disposed between the first electrode and the second electrode;

an optical pattern layer disposed on the light emitting element layer and comprising:

a first pattern layer having a first refractive index; and

a second pattern layer having a second refractive index less than the first refractive index; and

an optical member disposed between the light emitting element layer and the optical pattern layer or disposed on the optical pattern layer, wherein

the optical member comprises a color filter layer,

the color filter layer comprises a light shielding part disposed between a plurality of color filters, which are spaced apart from each other and an organic layer disposed on the plurality of color filters,

the light shielding part is configured to distinguish a boundary between adjacent color filters of the plurality of color filters, and

the organic layer is filled between the plurality of color filters.

11. The display device of claim 10 , wherein:

the light emitting element layer further comprises an encapsulation layer disposed on the second electrode, and

the optical pattern layer is directly disposed on the encapsulation layer.

12. The display device of claim 10 , wherein the first pattern layer comprises:

a base part; and

protruding parts disposed on the base part and spaced apart from each other,

wherein each of the protruding parts comprises:

a bottom surface adjacent to the base part;

a ceiling surface facing the bottom surface; and

a side surface extended between the bottom surface and the ceiling surface,

wherein each of the bottom surface and the ceiling surface has a circular or polygonal shape on a cross section parallel to the base part.

13. The display device of claim 12 , wherein in each of the protruding parts:

a width of the bottom surface is in a range from about 4 μm to about 10 μm,

a height that is a minimum spaced distance between the bottom surface and the ceiling surface is in a range from about 7 μm to about 15 μm, and

an inclination angle of the side surface with respect to the bottom surface on a cross section perpendicular to the base part is in a range from about 70° to about 90°.

14. The display device of claim 10 , wherein:

the first electrode is a reflective electrode, and

the second electrode is a transmissive electrode or a transflective electrode.

15. The display device of claim 10 , wherein the light emitting element layer comprises an organic electroluminescent element or a quantum dot light emitting element.

16. The display device of claim 10 , wherein:

the optical member further comprises a polarizing layer, and

the optical pattern layer is directly disposed on or below the polarizing layer.

17. The display device of claim 10 , wherein:

the optical pattern layer is directly disposed on the color filter layer.