Fluorescence light emitting element comprising a phosphor layer including phosphors and a binder made of an inorganic material

Patent metadata

Field	Value
Publication number	US-9475983-B2
Application number	US-201414525363-A
Country	US
Kind code	B2
Filing date	Oct 28, 2014
Priority date	Oct 31, 2013
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

A fluorescence light emitting element includes a phosphor layer that includes phosphors and a binder made of an inorganic material. A thermal conductivity B of the binder is larger than 1.88 times a thermal conductivity A of the phosphors. When the volume of the phosphors included in the phosphor layer is X and the volume of the binder included in the phosphor layer is Y, a relationship of X/Y>1/2 is satisfied.

First claim

What is claimed is:

1. A fluorescence light emitting element comprising:
a phosphor layer that includes phosphors and a binder made of an inorganic material,
wherein a thermal conductivity B of the binder is larger than 1.88 times a thermal conductivity A of the phosphors, and
a relationship of X/Y>1/2 is satisfied, where X denotes a volume of the phosphors included in the phosphor layer, and Y denotes a volume of the binder included in the phosphor layer.

2. The fluorescence light emitting element according to claim 1 ,
wherein a relationship of α≧2.4736×(B/A) −1.432 ×100 is satisfied, where α [vol %] denotes a volume concentration of the phosphors included in the phosphor layer.

3. The fluorescence light emitting element according to claim 1 ,
wherein the binder is selected from a group consisting of aluminum oxide, magnesium oxide, silicon carbide, and aluminum nitride.

4. The fluorescence light emitting element according to claim 1 ,
wherein the binder is made of aluminum oxide, and
a volume concentration of the phosphors is 66 vol % or more.

5. The fluorescence light emitting element according to claim 4 ,
wherein the volume concentration of the phosphors is 75 vol % or more and 95 vol % or less.

6. The fluorescence light emitting element according to claim 1 ,
wherein the binder is made of magnesium oxide, and
a volume concentration of the phosphors is 50 vol % or more and 80 vol % or less.

7. A light source device comprising the fluorescence light emitting element according to claim 1 .

8. A light source device comprising the fluorescence light emitting element according to claim 2 .

9. A light source device comprising the fluorescence light emitting element according to claim 3 .

10. A light source device comprising the fluorescence light emitting element according to claim 4 .

11. A light source device comprising the fluorescence light emitting element according to claim 5 .

12. A light source device comprising the fluorescence light emitting element according to claim 6 .

13. A projector comprising:
the light source device according to claim 7 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

14. A projector comprising:
the light source device according to claim 8 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

15. A projector comprising:
the light source device according to claim 9 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

16. A projector comprising:
the light source device according to claim 10 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

17. A projector comprising:
the light source device according to claim 11 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

18. A projector comprising:
the light source device according to claim 12 ;
an optical modulation device that modulates light emitted from the light source device to form image light; and
a projection optical system that projects light emitted from the optical modulation device.

Assignees

• Seiko Epson Corp

Inventors

• Kuroi Kiyoshi
• Hashizume Toshiaki

Classifications

• C09K11/7774

  Aluminates · CPC title

• C09K11/02 Primary

  Use of particular materials as binders, particle coatings or suspension media therefor · CPC title

• G03B21/005

  Projectors using an electronic spatial light modulator but not peculiar thereto · CPC title

• G03B21/204 Primary

  using secondary light emission, e.g. luminescence or fluorescence (using different colours G03B33/00; if related to video signals H04N9/3197) · CPC title

• H10H20/8511

  characterised by their material, e.g. binder · CPC title