Organic light emitting device
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.
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 disposed in contact with or adjacent to a side of the hole or electron injecting electrode layer opposite to a side facing the organic stacked structure,
wherein the scattering layer comprises scattering particles, of which refractive index is in a range of 1.0 to 3.5 and an average diameter is in a range of 50 nm to 20,000 nm,
wherein the low refractive organic layer comprises a low refractive material and an organic compound, and comprises 100 to 150 parts by weight of the low refractive material with respect to 100 parts by weight of the organic compound.
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 electrode layer 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 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.
8. The organic light emitting device according to claim 7 , further comprising: an encapsulating structure for protecting the organic stacked structure and the electron injecting electrode layer, wherein the encapsulating structure is attached on the hole injecting electrode layer below which the scattering layer is not formed.
9. The organic light emitting device according to claim 8 , 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.
10. The organic light emitting device according to claim 1 , wherein the low refractive material is selected from the group consisting of lithium fluoride (LiF), magnesium fluoride (MgF 2 ), potassium fluoride (KF), sodium fluoride (NaF), aluminum fluoride (AlF 2 ), barium fluoride (BaF 2 ), beryllium fluoride (BeF 2 ), cadmium fluoride (CdF 2 ), calcium fluoride (CaF 2 ), cesium fluoride (CsF), thorium fluoride (ThF 4 ), yttrium fluoride (YF 3 ), iron fluoride (FeCl 2 ), vanadium fluoride (V 2 O 5 ) and Na 2 Al 3 F 14 (Chiolite).
11. The organic light emitting device according to claim 1 , wherein the low refractive organic layer has a thickness of 15 nm or more.
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. Lighting comprising the organic light emitting device of claim 1 .