Image display device
View Patent ↗An organic EL element has a capping layer formed on a cathode layer. The capping layer contains a pigment that absorbs light that has a wavelength that is different from a wavelength of the light emitted from a light emitting layer, and has a reflectance that is higher at interface in multi-layered structure than a reflectance of the light emitted from the light emitting layer. The capping layer prevents incident light from outside from returning to the outside of the organic EL element.
1. A light emitting element comprising:
a substrate; a multi-layered structure on the substrate, including a first electrode layer, a second electrode layer and a light emitting layer between the first and the second electrode layers; and
an absorbing layer on the multi-layered structure, through which light emitted from the light emitting layer passes, wherein the absorbing layer has a higher refractive index than at least one layer of the multi-layered structure, and absorbs a different wavelength from light emitted from the light emitting layer, and the multi-layered structure is disposed between the substrate and the absorbing layer,
wherein the absorbing layer contains an additive absorbing the light having a different wavelength from the light emitted from the light emitting layer.
2. The light emitting element according to claim 1 ,
wherein the light emitted from the light emitting layer passes through the absorbing layer.
3. The light emitting element according to claim 1 , wherein the light emitting layer emits light of red color or blue color; wherein a wavelength of the light absorbed in the absorbing layer is from 500 nm to 560 nm.
4. The light emitting element according to claim 1 , wherein the absorbing layer comprises ZnS, TiO2 or ITO.
5. An image display device comprising a plurality of the light emitting elements according to claim 1 .
6. A light emitting element comprising:
a substrate; a multi-layered structure on the substrate, including a first electrode layer, a second electrode layer and a light emitting layer between the first and the second electrode layers; and
an absorbing layer on the multi-layered structure, through which light emitted from the light emitting layer passes, wherein the absorbing layer has a higher refractive index than at least one layer of the multi-layered structure, and absorbs a different wavelength from light emitted from the light emitting layer, and the multi-layered structure is disposed between the substrate and the absorbing layer,
wherein the absorbing layer has a higher refractive index than all layers of the multi-layered structure.
7. A light emitting element comprising:
a substrate;
a first multi-layered structure on the substrate, including a first electrode layer, a second electrode layer and a light emitting layer between the first and the second electrode layers;
a second multi-layered structure on the first multi-layered structure, including a absorbing layer and a high-refraction layer, the absorbing layer absorbing light of a different wavelength from light emitted from the light emitting layer, the high-refraction layer having a higher refractive index than at least one layer of the first multi-layered structure,
wherein light emitted from the light emitting layer passes through the second multi-layered structure,
wherein the absorbing layer contains an additive absorbing the light having a different wavelength from the light emitted from the light emitting layer.
8. The light emitting element according to claim 7 , wherein the reflectance of the absorbing layer is lower than 0.4.
9. The light emitting element according to claim 7 , wherein a combined thickness of the absorbing layer and the high-refraction layer is from 60 nm to 90 nm.
10. An image display device comprising a plurality of the light emitting elements according to claim 7 .
11. The light emitting element according to claim 7 , wherein the reflectance of the absorbing layer is lower than 0.54.
12. A light emitting element comprising:
a substrate;
a multi-layered structure on the substrate, including a first electrode layer, a second electrode layer and a light emitting layer between the first and second electrode layers; and
an absorbing layer arranged on the multi-layered structure, having a higher refractive index than at least one layer of the multi-layered structure, the absorbing layer absorbing light of a different wavelength from light emitted from the light emitting layer,
wherein the light emitted from the light emitting layer passes through the absorbing layer, and the multilayered structure is disposed between the substrate and the absorbing layer,
wherein the absorbing layer has a higher refractive index than all layers of the multi-layered structure.
13. The light emitting element according to claim 12 , wherein the light emitting layer emits light of red color or blue color; wherein a wavelength of the light absorbed in the absorbing layer is from 500 nm to 560 nm.
14. The light emitting element according to claim 12 , wherein the absorbing layer comprises ZnS, TiO2, or ITO.
15. An image display device comprising a plurality of the light emitting elements according to claim 12 .