Display device and method of manufacturing a display device

1. A display device comprising:

a substrate;

an organic light-emitting diode that includes a first electrode, a first organic layer provided on the first electrode, and a second electrode provided on the first organic layer, which are provided for each pixel on the substrate;

an insulating layer that is formed along a boundary of the pixel and has an opening portion in a light-emitting region of the pixel so as to expose the first organic layer;

a first refractive index layer; and

a second refractive index layer,

wherein the first refractive index layer is on the insulating layer and the organic light-emitting diode, is made of a material having a first refractive index, and has a first recessed portion overlapping with the insulating layer in plan view, and

wherein the second refractive index layer is inside the first recessed portion without overlapping with the opening portion and is made of a material having a second refractive index lower than the first refractive index.

2. The display device according to claim 1 ,

wherein the first refractive index layer includes a first inorganic insulating layer and a second inorganic insulating layer provided above the first inorganic insulating layer, and

wherein a second organic layer is provided between the first inorganic insulating layer and the second inorganic insulating layer in the light-emitting region.

3. The display device according to claim 2 ,

wherein the second organic layer has a second recessed portion overlapping with the insulating layer, and

wherein the second inorganic insulating layer is provided along an upper surface shape of the second organic layer and has the first recessed portion having a shape conforming to the second recessed portion, and the first inorganic insulating layer and the second inorganic insulating layer are in contact with each other at the second recessed portion.

4. The display device according to claim 1 ,

wherein the insulating layer has a third recessed portion on the upper surface of the insulating layer,

wherein the first refractive index layer has a shape conforming to an upper surface shape of the insulating layer and overlapping with the insulating layer, and

wherein the first recessed portion overlaps with the third recessed portion in plan view.

5. The display device according to claim 1 , wherein the first recessed portion includes an inner side surface curved toward an opening side of the first recessed portion.

6. The display device according to claim 1 , wherein the first refractive index layer includes silicon.

7. The display device according to claim 1 , wherein the second refract index layer includes any one of the air, nitrogen gas, and an organic material having transparency as a constituent material.

8. The display device according to claim 1 , wherein the first recessed portion is provided so as to surround one light-emitting region or a plurality of the light-emitting regions in plan view.

9. The display device according to claim 8 ,

wherein the first recessed portion is formed in a region having a substantially rectangular shape in plan view, and

wherein, in the substantially rectangular shape, a length of a long side is two times or more a length of a short side.