Organic electroluminescent device and display panel

Patent metadata

Field	Value
Publication number	US-12295205-B2
Application number	US-202117519316-A
Country	US
Kind code	B2
Filing date	Nov 4, 2021
Priority date	Mar 17, 2021
Publication date	May 6, 2025
Grant date	May 6, 2025

Abstract

The present disclosure provides an organic electroluminescent device and a display panel. The organic electroluminescent device provided by the present disclosure includes: a first electrode, a second electrode and a light-emitting layer located between the first electrode and the second electrode, and an optical structure located at a side of the first electrode facing away from the light-emitting layer. A reflectance of the optical structure with respect to light of a specific wavelength band is greater than a reflectance of the optical structure with respect to light of a wavelength band other than the specific wavelength band, the light of the specific wavelength band being light emitted by the organic electroluminescent device, and a material for forming the optical structure includes at least one of nitrogen, oxygen, and fluorine.

First claim

What is claimed is:

1. An organic electroluminescent system comprising a plurality of organic electroluminescent devices, each, comprising: a first electrode, a second electrode, a light emitting layer between the first electrode and the second electrode, and an optical structure, wherein in the organic electroluminescent devices emitting light of different colors, thicknesses of the optical structures are different; the first electrodes have recesses having depths corresponding to the thicknesses of the optical structures at one side of the first electrode facing away from the light emitting layer; the optical structure is located in the corresponding recess of the first electrodes, so that a sum of the thickness of the optical structure and a thickness of a portion of the first electrode in which the recess is formed in each of the organic electroluminescent devices is identical and is equal to a thickness of a portion of the first electrode in which the recess is not formed,
wherein a reflectance of the optical structure with respect to light of a specific wavelength band is greater than a reflectance of the optical structure with respect to light of a wavelength band other than the specific wavelength band, the light of the specific wavelength band being light emitted by the organic electroluminescent device, and a material forming the optical structure comprises at least one chemical element selected from the group consisting of nitrogen, oxygen, and fluorine.

2. The organic electroluminescent system of claim 1 , wherein a material for forming the first electrode and a material for forming the second electrode each comprise a metal oxide.

3. The organic electroluminescent system of claim 1 , wherein the optical structure comprises a plurality of first optical film layers and a plurality of second optical film layers, the plurality of first optical film layers and the plurality of second optical film layers being alternately disposed with each other, and
wherein refractive indices of the plurality of first optical film layers are greater than refractive indices of the plurality of second optical film layers.

4. The organic electroluminescent system of claim 3 , wherein at least some of the plurality of first optical film layers have different materials.

5. The organic electroluminescent system of claim 3 , wherein at least some of the plurality of second optical film layers have different materials.

6. The organic electroluminescent system of claim 3 , wherein a material for forming the plurality of first optical film layers comprises at least one chemical compound selected from the group consisting of silicon nitride, aluminum oxide, and titanium dioxide, and a material for forming the plurality of second optical film layers comprises at least one chemical compound selected from the group consisting of silicon oxide, barium fluoride, and calcium fluoride.

7. The organic electroluminescent system of claim 3 , wherein a thickness of each of the plurality of first optical film layers is different from a thickness of each of the plurality of second optical film layers.

8. The organic electroluminescent system of claim 7 , wherein the organic electroluminescent system comprises a red organic electroluminescent device, a green organic electroluminescent device, and a blue organic electroluminescent device;
in the optical structure of the red organic electroluminescent device, the thickness of each of the plurality of first optical film layers is greater than the thickness of each of the plurality of second optical film layers;
in the optical structure of the green organic electroluminescent device, the thickness of each of the plurality of first optical film layers is greater than the thickness of each of the plurality of second optical film layers; and
in the optical structure of the blue organic electroluminescent device, the thickness of each of the plurality of first optical film layers is less than the thickness of each of the plurality of second optical film layers.

9. The organic electroluminescent system of claim 1 , wherein the first electrode covers at least the optical structure.

10. The organic electroluminescent system of claim 3 , wherein numbers, materials, and thicknesses of first and second optical film layers included in the optical structure of the organic electroluminescent system depend on a color of light emitted by an organic electroluminescent device.

11. The organic electroluminescent system of claim 10 , wherein the optical structure comprises 6 to 8 first optical film layers and 6 to 8 second optical film layers;
the material for forming the first optical film layers comprises silicon nitride, and the material for forming the second optical film layers comprises silicon dioxide; and
the thickness of each of the first optical film layers is 40 nanometers, and the thickness of each of the second optical film layers is 5 nanometers.

12. The organic electroluminescent system of claim 11 , wherein the organic electroluminescent device is a red organic electroluminescent device, and the optical structure is at a side of the first electrode of the red organic electroluminescent device facing away from the light-emitting layer.

13. The organic electroluminescent system of claim 10 , wherein the optical structure comprises 5 to 7 first optical film layers and 5 to 7 second optical film layers;
the material for forming the first optical film layers comprises silicon nitride, and the material for forming the second optical film layers comprises silicon dioxide; and
the thickness of each of the first optical film layers is 35 nanometers, and the thickness of each of the second optical film layers is 10 nanometers.

14. The organic electroluminescent system of claim 13 , wherein the organic electroluminescent device is a green organic electroluminescent device, and the optical structure is at a side of the light-emitting layer facing away from the first electrode of the green organic electroluminescent device.

15. The organic electroluminescent system of claim 10 , wherein the optical structure comprises 3 to 5 first optical film layers and 3 to 5 second optical film layers;
the material for forming the first optical film layers comprises silicon nitride, and the material for forming the second optical film layers comprises silicon dioxide; and
the thickness of each of the first optical film layers is 20 nanometers, and the thickness of each of the second optical film layers is 45 nanometers.

16. The organic electroluminescent system of claim 15 , wherein the organic electroluminescent device is a blue organic electroluminescent device, and the optical structure is at a side of the first electrode of the blue organic electroluminescent device facing away from the light-emitting layer.

17. A display panel, comprising the organic electroluminescent system of claim 1 .

18. The display panel of claim 17 , wherein the display panel includes a display region, and at least a partial region of the display region is a mounting region; the organic electroluminescent device is in the mounting region.

Assignees

• Boe Technology Group Co Ltd

Inventors

• Fan Yibing
• Wang Chunyang
• Qu Caiyu
• Zhang Huijuan
• Li Liangjian
• Liu Zheng

Classifications

• H10K59/65

  OLEDs integrated with inorganic image sensors · CPC title

• H10K59/879 Primary

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

• H10K59/80515

  characterised by their shape · CPC title

• H10K2102/351

  Thickness · CPC title

• H10K2102/103

  comprising indium oxides, e.g. ITO · CPC title