Display device

Patent metadata

Field	Value
Publication number	US-9673264-B2
Application number	US-201514873938-A
Country	US
Kind code	B2
Filing date	Oct 2, 2015
Priority date	Mar 4, 2011
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

To provide a display device with low power consumption. The display device includes a plurality of pixels each having a light-emitting element having a structure in which light emitted from a light-emitting layer is resonated between a reflective electrode and a light-transmitting electrode, wherein no color filter layers are provided or color filter layers with high transmittance are provided in pixels for light with relatively short wavelengths (e.g., pixels for blue and/or green), and a color filter layer is selectively provided in pixels for light with a long wavelength (e.g., pixels for red), and thereby maintaining color reproducibility and consuming less power.

First claim

What is claimed is:

1. A display device comprising:
a first substrate;
a first light-emitting element over the first substrate;
a second light-emitting element over the first substrate;
a third light-emitting element over the first substrate;
a first color filter layer having a transmission center wavelength in a green wavelength region, the first color filter layer overlaps with the second light-emitting element; and
a second color filter layer having a transmission center wavelength in a red wavelength region, the second color filter layer overlaps with the third light-emitting element,
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises:
a reflective electrode;
a first light-emitting layer over the reflective electrode;
a second light-emitting layer over the first light-emitting layer; and
a light-transmitting electrode over the second light-emitting layer,

wherein emission colors of the first light-emitting layer and the second light-emitting layer are different from each other,
wherein a color filter layer overlapping with the first light-emitting element is not provided,
wherein a distance between the reflective electrode and the light-transmitting electrode of the first light-emitting element, a distance between the reflective electrode and the light-transmitting electrode of the second light-emitting element, and a distance between the reflective electrode and the light-transmitting electrode of the third light-emitting element are different from each other, and
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises a layer including an organic compound between the first light-emitting layer and the second light-emitting layer.

2. The display device according to claim 1 ,
wherein the second light-emitting element comprises a first light-transmitting conductive layer over the reflective electrode,
wherein the third light-emitting element comprises a second light-transmitting conductive layer over the reflective electrode, and
wherein a thickness of the first light-transmitting conductive layer and a thickness of the second light-transmitting conductive layer are different from each other.

3. The display device according to claim 1 , wherein an area of the first light-emitting element is smaller than an area of the third light-emitting element.

4. The display device according to claim 1 ,
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises a layer including an organic compound between the reflective electrode and the light-transmitting electrode, and
wherein a thickness of the layer of the first light-emitting element, a thickness of the layer of the second light-emitting element, and a thickness of the layer of the third light-emitting element are different from each other.

5. The display device according to claim 1 , further comprising a metal plate and an adhesive layer between the first substrate and the metal plate.

6. The display device according to claim 1 , wherein the first light-emitting layer and the second light-emitting layer comprise a phosphorescent compound.

7. A display device comprising:
a first substrate;
a first light-emitting element over the first substrate;
a second light-emitting element over the first substrate;
a third light-emitting element over the first substrate;
a first color filter layer having a transmission center wavelength in a green wavelength region, the first color filter layer overlaps with the second light-emitting element; and
a second color filter layer having a transmission center wavelength in a red wavelength region, the second color filter layer overlaps with the third light-emitting element,
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises:
a reflective electrode;
a first light-emitting layer over the reflective electrode;
a second light-emitting layer over the first light-emitting layer; and
a light-transmitting electrode over the second light-emitting layer,

wherein emission colors of the first light-emitting layer and the second light-emitting layer are different from each other,
wherein a distance between the reflective electrode and the light-transmitting electrode of the first light-emitting element, a distance between the reflective electrode and the light-transmitting electrode of the second light-emitting element, and a distance between the reflective electrode and the light-transmitting electrode of the third light-emitting element are different from each other,
wherein a color filter layer overlapping with the first light-emitting element is not provided,
wherein the second color filter layer has a maximum transmittance in the red wavelength region higher than a maximum transmittance of the first color filter layer region in the green wavelength region, and
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises a layer including an organic compound between the first light-emitting layer and the second light-emitting layer.

8. The display device according to claim 7 ,
wherein the second light-emitting element comprises a first light-transmitting conductive layer over the reflective electrode,
wherein the third light-emitting element comprises a second light-transmitting conductive layer over the reflective electrode, and
wherein a thickness of the first light-transmitting conductive layer and a thickness of the second light-transmitting conductive layer are different from each other.

9. The display device according to claim 7 , wherein an area of the first light-emitting element is smaller than an area of the third light-emitting element.

10. The display device according to claim 7 ,
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises a layer including an organic compound between the reflective electrode and the light-transmitting electrode, and
wherein a thickness of the layer of the first light-emitting element, a thickness of the layer of the second light-emitting element, and a thickness of the layer of the third light-emitting element are different from each other.

11. The display device according to claim 7 , further comprising a metal plate and an adhesive layer between the first substrate and the metal plate.

12. The display device according to claim 7 , wherein the first light-emitting layer and the second light-emitting layer comprise a phosphorescent compound.

13. A display device comprising:
a first substrate;
a first light-emitting element over the first substrate;
a second light-emitting element over the first substrate;
a third light-emitting element over the first substrate;
a first color filter layer having a transmission center wavelength in a green wavelength region, the first color filter layer overlaps with the second light-emitting element; and
a second color filter layer having a transmission center wavelength in a red wavelength region, the second color filter layer overlaps with the third light-emitting element,
wherein the first light-emitting element, the second light-emitting element, and the third light-emitting element each comprises:
a reflective electrode;
a first light-emitting layer over the reflective electrode;
a second light-emitting layer over the first light-emitting layer; and
a light-transmitting electrode over the second light-

Assignees

• Semiconductor Energy Lab

Inventors

• Ohsawa Nobuharu
• Sasaki Toshiki
• Seo Satoshi

Classifications

• H10K59/87

  Passivation; Containers; Encapsulations · CPC title

• H10K59/80524

  Transparent cathodes, e.g. comprising thin metal layers · CPC title

• H10K59/80518

  Reflective anodes, e.g. ITO combined with thick metallic layers · CPC title

• H10K59/876 Primary

  comprising a resonant cavity structure, e.g. Bragg reflector pair · CPC title

• H10K59/8052

  Cathodes · CPC title