Display device comprising stack of insulating refractive layers

1. A display device comprising:

a display panel including a plurality of light emitting regions and a non-light emitting region adjacent to the plurality of light emitting regions;

a first insulation layer disposed on the display panel, the first insulation layer having a first refractive index, and having a plurality of first openings defined in a region overlapping the plurality of light emitting regions;

a second insulation layer covering the display panel and the first insulation layer and having a second refractive index greater than the first refractive index of the first insulation layer;

a third insulation layer disposed on the second insulation layer, the third insulation layer having the first refractive index, and having a plurality of second openings defined in a region overlapping the plurality of light emitting regions; and

a fourth insulation layer covering the second insulation layer and the third insulation layer and having the second refractive index.

2. The display device of claim 1 , wherein each of the second insulation layer and the fourth insulation layer overlaps the plurality of first openings on a plane.

3. The display device of claim 1 , wherein the first refractive index is in a range of about 1.45 to about 1.55, and the second refractive index is in a range of about 1.65 to about 1.80.

4. The display device of claim 1 , wherein

the first insulation layer and the third insulation layer comprise a first organic matter, and

the second insulation layer and the fourth insulation layer comprise a second organic matter different from the first organic matter.

5. The display device of claim 4 , wherein the first organic matter comprises an acrylic resin.

6. The display device of claim 4 , wherein the second organic matter comprises zirconia.

7. The display device of claim 1 , wherein a thickness of the first insulation layer is in a range of about 1.5 μm to about 5 μm, and a maximum thickness of the second insulation layer is in a range of about 3 μm to about 20 μm.

8. The display device of claim 1 , wherein

the first insulation layer comprises a first through-surface defining each of the plurality of first openings, and

an angle between the first through-surface and a surface on which the first insulation layer is disposed is in a range of about 60° to about 80°.

9. The display device of claim 8 , wherein an absolute value of the difference between a width of each of the plurality of first openings and a width of each of the plurality of light emitting regions is about 3 μm or less.

10. The display device of claim 1 , further comprising:

a fifth insulation layer disposed on the fourth insulation layer, the fifth insulation layer having the first refractive index, and having a plurality of third openings defined in a region overlapping the plurality of light emitting regions; and

a sixth insulation layer covering the fourth insulation layer and the fifth insulation layer and having the second refractive index.

11. The display device of claim 10 , wherein

the plurality of second openings are extended in a first direction and spaced apart in a second direction crossing the first direction on a plane, and

the plurality of third openings are extended in the second direction and spaced apart in the first direction on the plane.

12. The display device of claim 1 , further comprising an input sensing layer between the display panel and the first insulation layer.