LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, ELECTRONIC DEVICE, AND LIGHTING DEVICE

• US 20150303392A1
• Filed: 04/14/2015
• Published: 10/22/2015
• Est. Priority Date: 04/18/2014
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: OHSAWA, Nobuharu, NONAKA, Yusuke
• Application Number:
  US14/685,758
• Publication Number:
  US 20150303392A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 2101/27 Combination of fluorescent and phosphorescent emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/13 comprising stacked EL layers within one EL unit
• CPC Class Codes: H10K 85/342 comprising iridium
• CPC Class Codes: H10K 85/622 containing four rings, e.g. pyrene
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: H10K 85/633 comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: H10K 85/6572 comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole
• CPC Class Codes: H10K 85/6576 comprising only sulfur in the heteroaromatic polycondensed ring system, e.g. benzothiophene

Abstract

The light-emitting element includes an EL layer between a pair of electrodes. The EL layer includes a light-emitting layer. The light-emitting layer includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer and the second light-emitting layer contain light-emitting substances emitting light with different colors. Any one of the first light-emitting layer and the second light-emitting layer is not formed partly so that the light-emitting layer includes a region where the any the other of the first light-emitting layer and the second light-emitting layer is only formed. A first light emitted from a region of the light-emitting layer where the first light-emitting layer and the second light-emitting layer overlap with each other is different in color from a second light emitted from a region including the non-formation region. The first light and the second light can be obtained from the light-emitting layer at the same time.

Claims

1. A light-emitting element comprising:

a pair of electrodes; and

a light-emitting layer between the pair of electrodes, the light-emitting layer comprising a first light-emitting layer and a second light-emitting layer,

wherein the light-emitting layer comprises a first region where the first light-emitting layer and the second light-emitting layer overlap with each other and a second region where the first light-emitting layer is not formed.

2. The light-emitting element according to claim 1,

wherein the first region and the second region overlap with the pair of electrodes.

3. The light-emitting element according to claim 1,

wherein the first region is surrounded by the second region.

4. The light-emitting element according to claim 1,

wherein light emitted from the light-emitting layer comprises a first emission spectrum obtained from the first region and a second emission spectrum obtained from the second region.

5. The light-emitting element according to claim 1,

wherein a first light emitted from the first region is different in color from a second light emitted from the second region.

6. The light-emitting element according to claim 4,

wherein the first emission spectrum has a peak in a range of 500 nm to 650 nm, and

wherein the second emission spectrum has a peak in a range of 400 nm to 500 nm.

7. The light-emitting element according to claim 1,

wherein the first light-emitting layer emits an yellow-orange light and the second light-emitting layer emits a blue light.

8. The light-emitting element according to claim 1,

wherein the first light-emitting layer comprises a stack of a layer containing a green-light-emitting substance and a layer containing an orange-light-emitting substance.

9. The light-emitting element according to claim 1,

wherein the first light-emitting layer contains a phosphorescent substance and the second light-emitting layer contains a fluorescent substance.

10. The light-emitting element according to claim 1,

wherein the first region has one of a substantially rectangular shape, a substantially square shape, a circular shape, a triangular shape, and an elliptical shape.

11. A light-emitting device comprising the light-emitting element according to claim 1.

12. An electronic device comprising the light-emitting device according to claim 11.

13. A lighting device comprising the light-emitting device according to claim claim 11.

14. A light-emitting element comprising:

a pair of electrodes; and

a light-emitting layer between the pair of electrodes, the light-emitting layer comprising a first light-emitting layer including a first light-emitting substance and a second light-emitting layer including a second light-emitting substance,

wherein the first light-emitting substance and the second light-emitting substance emit light with different colors from each other, and

wherein the light-emitting layer comprises a first region where the first light-emitting layer and the second light-emitting layer overlap with each other and a second region where one of the first light-emitting layer and the second light-emitting layer is not formed.

15. The light-emitting element according to claim 14,

wherein the first region and the second region overlap with the pair of electrodes.

16. The light-emitting element according to claim 14,

wherein the first region is surrounded by the second region.

17. The light-emitting element according to claim 14,

wherein a first light emitted from the first region is different in color from a second light emitted from the second region, and

wherein the light-emitting layer is configured to emit the first light and the second light at the same time.

18. The light-emitting element according to claim 14,

wherein a first light emitted from the first region is different in color from a second light emitted from the second region.

19. The light-emitting element according to claim 14,

wherein the first light-emitting layer emits an yellow-orange light and the second light-emitting layer emits a blue light.

20. The light-emitting element according to claim 14,

wherein the first light-emitting layer comprises a stack of a layer containing a green-light-emitting substance and a layer containing an orange-light-emitting substance.

21. The light-emitting element according to claim 14,

wherein the first light-emitting layer contains a phosphorescent substance and the second light-emitting layer contains a fluorescent substance.

22. The light-emitting element according to claim 14,

wherein the first region has one of a substantially rectangular shape, a substantially square shape, a circular shape, a triangular shape, and an elliptical shape.

23. A light-emitting device comprising the light-emitting element according to claim 14.

24. An electronic device comprising the light-emitting device according to claim 23.

25. A lighting device comprising the light-emitting device according to claim 23.

26. A light-emitting element comprising:

a pair of electrodes; and

a light-emitting layer between the pair of electrodes, the light-emitting layer comprising a first light-emitting layer emitting phosphorescence and a second light-emitting layer emitting fluorescence,

wherein the light-emitting layer comprises a first region where the first light-emitting layer and the second light-emitting layer overlap with each other and a second region where one of the first light-emitting layer and the second light-emitting layer is not formed,

wherein a first light emitted from the first region is different in color from a second light emitted from the second region.

27. The light-emitting element according to claim 26,

wherein the first region and the second region overlap with the pair of electrodes.

28. The light-emitting element according to claim 26,

wherein the first region is surrounded by the second region.

29. The light-emitting element according to claim 26,

wherein the light-emitting layer is configured to emit the first light and the second light at the same time.

30. The light-emitting element according to claim 26,

wherein the first light-emitting layer comprises a layer in which an exciplex is formed.

31. The light-emitting element according to claim 26,

wherein the second light-emitting layer comprises a fluorescent substance and a host material having a Ti level lower than that of the fluorescent substance.

32. The light-emitting element according to claim 26,

wherein the first light-emitting layer emits an yellow-orange light and the second light-emitting layer emits a blue light.

33. The light-emitting element according to claim 26,

wherein the first light-emitting layer comprises a stack of a layer containing a green-light-emitting substance and a layer containing an orange-light-emitting substance.

34. The light-emitting element according to claim 26,

wherein the first region has one of a substantially rectangular shape, a substantially square shape, a circular shape, a triangular shape, and an elliptical shape.

35. A light-emitting device comprising the light-emitting element according to claim 26.

36. An electronic device comprising the light-emitting device according to claim 35.

37. A lighting device comprising the light-emitting device according to claim 35.