Light-emitting device, display device and illumination device

Patent metadata

Field	Value
Publication number	US-9512976-B2
Application number	US-201314391695-A
Country	US
Kind code	B2
Filing date	Apr 10, 2013
Priority date	Apr 13, 2012
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A light-scattering body includes at least light-transmitting resin, and first particles and second particles which are dispersed in the light-transmitting resin. An average grain size Da of the first particles is greater than an average grain size Db of the second particles. A refractive index na of the first particles is less than a refractive index nb of the second particles. The average grain size Db of the second particles is within a range of 150 nm≦Db≦300 nm.

First claim

The invention claimed is:

1. A light-emitting device comprising: an excitation light source which emits blue light; and a substrate, which is arranged so as to face the excitation light source, and on which a red phosphor film that forms a red pixel emitting red fluorescence by being excited with the blue light, a green phosphor film that forms a green pixel emitting green fluorescence by being excited with the blue light, and a blue scattering body film that forms a blue pixel scattering the blue light are formed,
wherein the substrate with the blue scattering body film formed thereon is configured of a light-scattering body device,
the light-scattering body device comprises: a light source; and the light-scattering body substrate which is arranged so as to face the light source,
the light-scattering body substrate comprises at least a light-scattering body film,
the light-scattering body film comprises at least the light-scattering body, and
the light-scattering body comprises at least light-transmitting resin; and first particles and second particles which are dispersed in the light-transmitting resin,
wherein an average grain size Da of the first particles is greater than an average grain size Db of the second particles, a refractive index na of the first particles is smaller than a refractive index nb of the second particles, and the average grain size Db of the second particles is within a range of 150 nm≦Db≦300 nm.

2. The light-emitting device according to claim 1 ,
wherein at least one of the red phosphor film and the green phosphor film further includes a light-scattering body,
wherein the light-scattering body includes at least light-transmitting resin and first particles and second particles which are dispersed in the light-transmitting resin, and
wherein an average grain size Da of the first particles is greater than an average grain size Db of the second particles, a refractive index na of the first particles is smaller than a refractive index nb of the second particles, and the average grain size Db of the second particles is within a range of 150 nm≦Db≦300 nm.

3. The light-emitting device according to claim 1 , further comprising: a barrier with a light reflecting property which is formed along at least one side surface in a film thickness direction of the red phosphor film and the green phosphor film.

4. The light-emitting device according to claim 1 , further comprising: a wavelength selecting transflective film provided on a side of incident surfaces, on which the blue light is incident, of the red phosphor film and the green phosphor film, the wavelength selecting transflective film transmitting at least light in a predetermined wavelength region around a peak wavelength of the blue light and reflecting at least light in a predetermined wavelength region around a light emission peak wavelength of the phosphor films.

5. The light-emitting device according to claim 1 , further comprising: a low-refractive-index film provided between the phosphor films and the substrate, the low-refractive-index film having a refractive index smaller than that of the substrate.

6. The light-emitting device according to claim 1 , further comprising: a light absorption layer provided in at least one of locations between the red phosphor film and the green phosphor film and between the red phosphor film and the blue scattering body film, which are adjacent to each other.

7. The light-emitting device according to claim 3 ,
wherein at least a region, which is in contact with the light-scattering film, of the barrier has a light-scattering property.

8. The light-emitting device according to claim 5 ,
wherein the refractive index of the low-refractive-index film is within a range of 1 or more and 1.5 or less.

9. The light-emitting device according to claim 5 ,
wherein the low-refractive-index film is in the form of gas.

10. The light-emitting device according to claim 6 ,
wherein the light absorption layer is formed on at least one of an upper surface and a lower surface of the barrier.

11. A display device comprising: at least a light-emitting device, wherein
the light-emitting device comprises: an excitation light source which emits blue light; and a substrate, which is arranged so as to face the excitation light source, and on which a red phosphor film that forms a red pixel emitting red fluorescence by being excited with the blue light, a green phosphor film that forms a green pixel emitting green fluorescence by being excited with the blue light, and a blue scattering body film that forms a blue pixel scattering the blue light are formed,
the substrate with the blue scattering body film formed thereon is configured of a light-scattering body device,
the light-scattering body device comprises: a light source; and the light-scattering body substrate which is arranged so as to face the light source,
the light-scattering body substrate comprises at least a light-scattering body film,
the light-scattering body film comprises at least the light-scattering body, and
the light-scattering body comprises at least light-transmitting resin; and first particles and second particles which are dispersed in the light-transmitting resin,
wherein an average grain size Da of the first particles is greater than an average grain size Db of the second particles, a refractive index na of the first particles is smaller than a refractive index nb of the second particles, and the average grain size Db of the second particles is within a range of 150 nm Db 300 nm.

12. The display device according to claim 11 , further comprising: an active matrix drive element corresponding to the excitation light source.

13. The display device according to claim 11 ,
wherein the excitation light source is one of a light-emitting diode, an organic electroluminescence element, and an inorganic electroluminescence element.

14. The display device according to claim 11 , further comprising: a liquid crystal element which is provided between the excitation light source and the substrate, the liquid crystal element being able to control transmittance of the blue light,
wherein the excitation light source is a plane-shaped light source.

15. The display device according to claim 11 ,
wherein the excitation light source emits blue light with a directivity.

16. The display device according to claim 11 , further comprising: a polarizer which is provided between the excitation light source and the substrate, the polarizer having an extinction ratio of 10000 or more at a wavelength of 435 nm or more and 480 nm or less.

17. The display device according to claim 11 , further comprising: color filters between the substrate and the red phosphor film, the green phosphor film, and the blue scattering body film.

18. An illumination device comprising: a light-emitting device, wherein
the light-emitting device comprises: an excitation light source which emits blue light; and a substrate, which is arranged so as to face the excitation light source, and on which a red phosphor film that forms a red pixel emitting red fluorescence by being excited with the blue light, a green phosphor film that forms a green pixel emitting green fluorescence by being excited with the blue light, and a blue scattering body film that forms a blue pixel scattering the blue light are formed,
the substrate with the blue scattering body film formed thereon is configured of a light-scattering body device,
the light-scattering body device comprises: a light source; and the light-scattering body substrate which is arranged

Assignees

• Sharp Kk

Inventors

• Bessho Hisanori
• Koden Mitsuhiro
• Fujita Yoshimasa

Classifications

• F21V5/002 Primary

  using microoptical elements for redirecting or diffusing light · CPC title

• H10K59/877

  comprising scattering means · CPC title

• G02B5/0242 Primary

  by means of dispersed particles · CPC title

• H10H20/8513

  having two or more wavelength conversion materials · CPC title

• H10H20/882

  Scattering means (H10H20/82 takes precedence) · CPC title