Display device with improved light extraction and emission efficiency

Patent metadata

Field	Value
Publication number	US-2025176412-A1
Application number	US-202418914805-A
Country	US
Kind code	A1
Filing date	Oct 14, 2024
Priority date	Nov 28, 2023
Publication date	May 29, 2025
Grant date	—

Abstract

In one aspect, a display panel includes a plurality of sub-pixels, each of the plurality of sub-pixels including a substrate; a first insulating layer on the substrate protruding away from the substrate, the first insulating layer having two side surfaces; and a light emitting device on the first insulating layer having a first electrode, a second electrode, and a light emitting layer, the first electrode at least partially covering the first insulating layer, wherein the second electrode is on the two side surfaces.

First claim

1 . A display panel comprising:
a plurality of sub-pixels, each of the plurality of sub-pixels including:
a substrate;
a first insulating layer on the substrate and protruding away from the substrate, the first insulating layer having two side surfaces; and
a light emitting device on the first insulating layer having a first electrode, a second electrode, and a light emitting layer, the first electrode at least partially covering the first insulating layer, wherein the second electrode is on the two side surfaces.

2 . The display panel of claim 1 , further comprising:
a reflective layer including a first layer on the first electrode and a second layer on the first layer, the first layer being formed of reflective material and the second layer being formed of transparent material.

3 . The display panel of claim 2 , wherein a thickness of the second layer is smaller than a thickness of the first electrode.

4 . The display panel of claim 1 , further comprising:
a second insulating layer, wherein the first insulating layer has a first refractive index and the second insulating layer has a second refractive index.

5 . The display panel of claim 4 , wherein the first refractive index is greater than the second refractive index.

6 . The display panel of claim 1 , further comprising:
a circuit element layer including a plurality of metal patterns.

7 . The display panel of claim 6 , further comprising:
a color filter on the circuit element layer covering the plurality of metal patterns.

8 . The display panel of claim 7 , wherein the color filter corresponds to an emission area of a corresponding one of the plurality of sub-pixels.

9 . The display panel of claim 1 , wherein the two side surfaces are inclined.

10 . The display panel of claim 2 , wherein the first layer contacts and covers the two side surfaces while partially covering a top surface of the first insulating layer.

11 . The display panel of claim 1 , wherein the light emitting layer has a multi-layer structure.

12 . The display panel of claim 1 , wherein the first electrode extends horizontally beyond the two side surfaces and partially covering a top surface of a second insulating layer, the first insulating layer being on the second insulating layer.

13 . The display panel of claim 6 , wherein the plurality of metal patterns are in a non-emission area between two adjacent ones of the plurality of sub-pixels and do not overlap with the first insulating layer and the first electrode.

14 . The display panel of claim 1 , wherein the first insulating layer is on a second insulating layer, the second insulating layer extending beyond a horizontal length of the first insulating layer to cover non-emission areas between adjacent ones of the plurality of sub-pixels.

15 . The display panel of claim 14 , wherein the second insulating layer has a first height from a top surface of the substrate in a first region and a second height from the top surface of the substrate in a second region.

16 . The display panel of claim 15 , wherein the first region is where the second insulating layer contacts the first insulating layer and the second region is where the second insulating layer covers the non-emission areas.

17 . The display panel of claim 2 , wherein the first electrode is horizontally disposed on a top surface of the first insulating layer.

18 . The display panel of claim 17 , further comprising:
a bank layer disposed between the first layer and each of the two side surfaces.

19 . The display panel of claim 18 , wherein the first layer covers the bank layer and a portion of the first electrode.

20 . The display panel of claim 19 , wherein the first layer contacts the portion of the first electrode through the bank layer via a contact hole.

21 . The display panel of claim 1 , wherein each of the plurality of sub-pixels has an emission area including a first emission area and two side emission areas, the two side emission areas corresponding to the two side surfaces.

22 . The display panel of claim 21 , wherein light is directly emitted in the first emission area.

23 . The display panel of claim 21 , wherein the light is emitted both directly and via reflection in the two side emission areas.

Assignees

• Lg Display Co Ltd

Inventors

• Choi Howon
• Kim Kyungmin

Classifications

• H10K59/80515

  characterised by their shape · CPC title

• H10K59/38

  comprising colour filters or colour changing media [CCM] · CPC title

• H10K59/124 Primary

  Insulating layers formed between TFT elements and OLED elements · CPC title

• H10K59/879

  comprising refractive means, e.g. lenses · CPC title

• H10K59/12

  Active-matrix OLED [AMOLED] displays · CPC title