Semiconductor light-emitting device
View Patent ↗There is provided a semiconductor light-emitting device including a semiconductor light-emitting element, a phosphor layer disposed in a light path of a light emitted from the semiconductor light-emitting element, containing a phosphor to be excited by the light and having a cross-section in a region of a diameter which is 1 mm larger than that of a cross-section of the light path, and a heat-releasing member disposed in contact with at least a portion of the phosphor layer and exhibiting a higher thermal conductance than that of the phosphor layer.
1. A semiconductor light-emitting device comprising:
a semiconductor light-emitting element;
a phosphor layer disposed in a light path of a light emitted from the semiconductor light-emitting element, containing a phosphor to be excited by the light and having a cross-section in a region of a diameter which is 1 mm larger than that of a cross-section of the light path; and
a heat-releasing member disposed in contact with at least a portion of the phosphor layer and exhibiting a higher thermal conductance than that of the phosphor layer.
2. The device according to claim 1 , wherein the phosphor layer has a cross-section in a region of the cross-section of the light path.
3. The device according to claim 1 , wherein the semiconductor light-emitting element is a semiconductor laser.
4. The device according to claim 1 , wherein the semiconductor light-emitting element is a high-output semiconductor light-emitting diode.
5. The device according to claim 1 , which is provided with a plurality of the semiconductor light-emitting elements.
6. The device according to claim 1 , wherein the phosphor layer is arranged at a position apart from the semiconductor light-emitting element, where maximum density of light emitted from the semiconductor light-emitting element is not more than 1000 mW/mm 2 .
7. The device according to claim 1 , wherein the semiconductor light-emitting element is formed of a III-Group nitride compound semiconductor.
8. The device according to claim 1 , wherein at least a portion of the light emitted from the phosphor layer is visible light.
9. The device according to claim 1 , wherein the heat-releasing member is formed of metal.
10. The device according to claim 1 , wherein the phosphor layer has a volume concentration distribution of the phosphor which is higher in a region distal to the semiconductor light-emitting element and is lower in a region proximal to the semiconductor light-emitting element.
11. The device according to claim 8 , wherein a layer containing no phosphor is disposed in a region of the light path which is located not more than 1 mm away from a light-emitting face of the semiconductor light-emitting element.
12. The device according to claim 1 , wherein a base material of the phosphor layer is formed of a material selected from the group consisting of a transparent resin, glass, a sintered body and a ceramic material.
13. The device according to claim 1 , wherein the phosphor is formed of a material selected from the group consisting of a silicate-based fluorescent material, an aluminate-based fluorescent material, a nitride-based fluorescent material, a sulfide-based fluorescent material, an oxysulfide-based fluorescent material, a YAG-based fluorescent material, a phosphate-based fluorescent material, a borate-based fluorescent material, and a halo-phosphate-based fluorescent material.
14. The device according to claim 1 , wherein the phosphor is formed of a material selected from the group consisting of a blue light-emitting fluorescent material, a yellow light-emitting fluorescent material, a green light-emitting fluorescent material, a red light-emitting fluorescent material and a white light-emitting fluorescent material.
15. The device according to claim 1 , wherein the phosphor layer has a columnar shape elongated along the light path.
16. The device according to claim 1 , wherein the phosphor layer has a shape similar to the light path and has a long cone-shape extending along the light path.
17. The device according to claim 1 , wherein the phosphor layer has a light incident surface of a convex shape.
18. The device according to claim 1 , wherein a layer formed of a material exhibiting a smaller refractive index than that of the phosphor layer is interposed between the semiconductor light-emitting element and the phosphor layer.
19. The device according to claim 1 , further comprising a rectangular parallelepiped housing having a wall, in which the semiconductor light-emitting element is arranged, wherein a portion of the wall which faces the light-emitting face of the semiconductor light-emitting element is formed of the heat-releasing member, the wall has a slit in a light incident region, and the phosphor layer is arranged in the slit.