ORGANIC LIGHT EMITTING DEVICE

• US 20150008422A1
• Filed: 09/19/2014
• Published: 01/08/2015
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: SON, Se Hwan, LEE, Jae In
• Granted Patent: US 9,577,224 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/22 characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/16 Electron transporting layers
• CPC Class Codes: H10K 50/165 comprising dopants
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 50/854 comprising scattering means
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

Provided are an organic light emitting device (OLED) and lighting. The illustrative OLED may minimize light absorption of a reflective electrode layer and evanescent coupling by surface plasmon, and exhibit excellent emitting efficiency.

Claims

1. An organic light emitting device, comprising:

an electron injecting electrode layer and a hole injecting electrode layer;

an organic stacked structure that is between the electron and hole injecting electrode layers, and that comprises an light emitting layer and a low refractive organic layer, of which a refractive index is 1.7 or less; and

a scattering layer that is in contact with or adjacent to a side opposite to a side adjacent to the organic stacked layer of the hole or electron injecting electrode.

2. The organic light emitting device according to claim 1, further comprising:

a base layer, on which the hole injecting electrode layer, the organic stacked structure and the electron injecting are sequentially formed.

3. The organic light emitting device according to claim 2, wherein the scattering layer is between the hole injecting electrode layer and the base layer.

4. The organic light emitting device according to claim 2, wherein the hole injecting electrode layer is a transparent electrode layer, and the electron injecting electrode layer is a reflective electrode layer.

5. The organic light emitting device according to claim 2, wherein the low refractive organic layer comprises an electron accepting organic compound.

6. The organic light emitting device according to claim 5, wherein the low refractive organic layer is in contact with the electron injecting electrode layer.

7. The organic light emitting device according to claim 1, wherein the low refractive organic layer comprises a low refractive material, of which a refractive index is 1.66 or less.

8. The organic light emitting device according to claim 7, wherein the low refractive material is lithium fluoride (LiF), magnesium fluoride (MgF₂), potassium fluoride (KF), sodium fluoride (NaF), aluminum fluoride (AlF₂), barium fluoride (BaF₂), beryllium fluoride (BeF₂), cadmium fluoride (CdF₂), calcium fluoride (CaF₂), cesium fluoride (CsF), thorium fluoride (ThF₄), yttrium fluoride (YF₃), iron fluoride (FeCl₂), vanadium fluoride (V₂O₅) and Na₂Al₃F₁₄ (Chiolite).

9. The organic light emitting device according to claim 7, wherein the low refractive organic layer comprises 5 to 200% of a low refractive material.

10. The organic light emitting device according to claim 1, wherein the low refractive organic layer has a thickness of 15 nm or more.

11. The organic light emitting device according to claim 1, wherein the scattering layer comprises scattering particles, of which a refractive index is in the range from 1.0 to 3.5 and an average diameter is in the range from 50 nm to 20,000 nm.

12. The organic light emitting device according to claim 1, wherein the scattering layer comprises an uneven structure.

13. The organic light emitting device according to claim 1, further comprising:

a planarizing layer on the scattering layer.

14. The organic light emitting device according to claim 13, wherein the planarizing layer has a refractive index of 1.8 to 3.5.

15. The organic light emitting device according to claim 13, wherein the planarizing layer comprises high refractive particles, of which an average diameter is in the range from 1 nm to 100 nm.

16. The organic light emitting device according to claim 15, wherein the high refractive particles are rutile titanium oxide.

17. The organic light emitting device according to claim 3, wherein the scattering layer has a smaller projected area than the hole injecting electrode layer, and the hole injecting electrode layer is formed on both of the scattering layer and the base layer on which the scattering layer is not formed.

18. The organic light emitting device according to claim 17, further comprising:

an encapsulating structure for protecting the organic stacked structure and the electron injecting electrode layer, and the encapsulating structure is attached on the hole injecting electrode layer below which the scattering layer is not formed.

19. The organic light emitting device according to claim 18, wherein the encapsulating structure is a glass can or a metal can, or a film covering entire surfaces of the organic stacked structure and the electron injection electrode layer.

20. Lighting comprising the organic light emitting device of claim 1.