Light-emitting device and lighting device

• US 8,455,884 B2
• Filed: 07/25/2011
• Issued: 06/04/2013
• Est. Priority Date: 07/26/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Ikeda, Hisao, Kawata, Takuya
• Primary Examiner(s): DANG, PHUC T
• Application Number:
  US13/189,770
• Publication Number:
  US 20120020085A1
• Time in Patent Office: 680 Days
• Field of Search: 257/79, 257/88, 257/89, 257/98
• US Class Current: 257/79
• CPC Class Codes: F21S 6/003 for task lighting, e.g. for reading or desk work, e.g. angle poise lamps
• CPC Class Codes: F21Y 2105/00 Planar light sources
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/15 Organic light-emitting diodes [OLED]
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

It is an object to improve light extraction efficiency in a light-emitting device and a lighting device. A light-emitting device includes a plurality of light-emitting portions, and a plurality of hemispherical components provided so as to overlap with the plurality of light-emitting portions. The plurality of hemispherical components are provided so as not to form a space therebetween in a region where the plurality of hemispherical components are adjacent to each other. When a refractive index of the hemispherical component is n and a radius of a bottom surface of the hemispherical component is b, the light-emitting portion is provided inside a circle whose radius r from a center of the bottom surface of the hemispherical component is b/n.

Claims

1. A light-emitting device comprising:

a plurality of light-emitting portions, each of the plurality of light-emitting portions comprising first and second electrodes and a light-emitting layer interposed therebetween; and

a plurality of hemispherical components, each of the plurality of hemispherical components having a flat surface on which the first electrode is provided,

wherein the plurality of hemispherical components are provided so as not to form a space therebetween in a region where the plurality of hemispherical components are adjacent to each other, and

wherein a refractive index of each of the plurality of the hemispherical components is greater than or equal to a refractive index of the light-emitting layer.

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

a plate-like component,

wherein the plurality of light-emitting portions are provided over one surface of the plate-like component, and

wherein flat surfaces of the plurality of hemispherical components are provided over the other surface of the plate-like component.

3. The light-emitting device according to claim 2,

wherein the plate-like component comprises glass, and

wherein each of the plurality of hemispherical components comprises resin.

4. A lighting device comprising the light-emitting device according to claim 1.

5. A light-emitting device comprising:

a plurality of light-emitting portions on a first surface of a plate-like component, each of the plurality of light-emitting portions comprising first and second electrodes and a light-emitting layer interposed therebetween; and

a plurality of hemispherical components on a second surface of the plate-like component, each of the plurality of hemispherical components having a flat surface in contact with he second surface of the plate-like component,

wherein the plurality of hemispherical components are arranged with a closest packed structure.

6. The light-emitting device according to claim 5,

wherein the refractive index of each of the plurality of hemispherical components is greater than or equal to a refractive index of the plate-like component, and the refractive index of the plate-like component is greater than or equal to a refractive index of the light-emitting layer.

7. The light-emitting device according to claim 5,

wherein the plate-like component comprises glass, and

wherein each of the plurality of hemispherical components comprises resin.

8. A lighting device comprising the light-emitting device according to claim 5.

9. A light-emitting device comprising:

a light-emitting portion comprising first and second electrodes and a light-emitting layer interposed therebetween; and

a hemispherical component having a flat surface;

a plate-like component between the first electrode of the light-emitting portion and the flat surface of the hemispherical component,

wherein a refractive index of the hemispherical component is n and a radius of the flat surface of the hemispherical component is b, and

wherein the light-emitting portion is provided inside a circle whose radius r from a center of the flat surface of the hemispherical component is b/n.

10. The light-emitting device according to claim 9,

wherein the refractive index of the hemispherical components is greater than or equal to a refractive index of the plate-like component, and the refractive index of the plate-like component is greater than or equal to a refractive index of the light-emitting layer.

11. The light-emitting device according to claim 9,

wherein the plate-like component comprises glass, and

wherein the hemispherical component comprises resin.

12. A lighting device comprising the light-emitting device according to claim 9.

13. A light-emitting device comprising:

a plurality of light-emitting portions, each of the plurality of light-emitting portions comprising first and second electrodes and a light-emitting layer interposed therebetween; and

a plurality of hemispherical components, each of the plurality of hemispherical components having a flat surface on which each of the plurality of light-emitting portions is provided,

wherein a refractive index of each of the plurality of hemispherical components is n and a radius of the flat surface of each of the plurality of hemispherical components is b,

wherein each of the plurality of light-emitting portions is provided inside a circle whose radius r from a center of the flat surface of each of the plurality of hemispherical components is b/n, and

wherein the refractive index of each of the plurality of hemispherical components is greater than or equal to a refractive index of the light-emitting layer.

14. The light-emitting device according to claim 13, wherein the plurality of hemispherical components are arranged with a closest packed structure.

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

16. A light-emitting device comprising:

a plate-like component;

a plurality of light-emitting portions provided on a first surface of the plate-like component, each of the plurality of light-emitting portions comprising first and second electrodes and a light-emitting layer interposed therebetween; and

a plurality of hemispherical components on a second surface of the plate-like component, each of the plurality of hemispherical components having a flat surface in contact with the second surface of the plate-like component interposed therebetween,

wherein a refractive index of each of the plurality of hemispherical components is n and a radius of a bottom surface of each of the plurality of hemispherical components is b, and

wherein each of the plurality of light-emitting portions is provided inside a circle whose radius r from a center of the bottom surface of each of the plurality of hemispherical components is b/n.

17. The light-emitting device according to claim 16,

wherein the plate-like component comprises glass, and

wherein each of the plurality of hemispherical components comprises resin.

18. The light-emitting device according to claim 16, wherein the plurality of hemispherical components are arranged with a closest packed structure.

19. A lighting device comprising the light-emitting device according to claim 16.

20. The light-emitting device according to claim 16, wherein the refractive index of each of the plurality of hemispherical components is greater than or equal to a refractive index of the plate-like component, and the refractive index of the plate-like component is greater than or equal to a refractive index of the light-emitting layer.