Light-emitting device
View Patent ↗A light-emitting device 1 includes a base 2 and a light-emitting element 3 that is disposed on the base 2 . The light-emitting element 3 is made up of a plurality of semiconductor layers including a light-emitting layer, and at the same time, is covered with a wavelength converting portion 4 that includes a wavelength converting material. The light-emitting layer emits primary light, and the wavelength converting material absorbs part of the primary light and emits secondary light. The luminance of the primary light emitted from the edge portion of the light extraction surface of the light-emitting device 3 is higher than the luminance of the primary light emitted from the inner region located inside the edge portion, and the ratio of the primary light and the secondary light that are emitted from a light extraction surface 6 of the wavelength converting portion 4 is substantially uniform across the light extraction surface 6 of the wavelength converting portion 4 . Thereby, a light color difference across the light extraction surface of the wavelength converting portion that covers the light-emitting element can be reduced further, and it is possible to irradiate an irradiation surface with light of uniform color.
1. A light-emitting device comprising a base, and a light-emitting element that is disposed on the base and that emits primary light,
wherein the light-emitting element comprises a plurality of semiconductor layers including a light-emitting layer,
the light-emitting element is covered with a wavelength converting portion that includes a wavelength converting material that absorbs part of the primary light and emits secondary light,
the light-emitting element includes at least two regions, the two regions being an edge portion and an inner region located inside the edge portion, and
a luminance of the primary light emitted from the edge portion of a light extraction surface provided on one principal surface of the light-emitting element is set higher than a luminance of the primary light emitted from the inner region that is located inside the edge portion.
2. The light-emitting device according to claim 1 , wherein the wavelength converting portion has a substantially uniform thickness, and the wavelength converting material is dispersed substantially uniformly.
3. The light-emitting device according to claim 1 ,
wherein the at least two regions are formed with diodes, the diode in the edge portion and the diode in the inner region located inside the edge portion are connected in series, and
the light-emitting layer of the diode in the edge portion has an area smaller than that of the light-emitting layer of the diode in the inner region located inside the edge portion.
4. The light-emitting device according to claim 1 ,
wherein the at least two regions are formed with diodes, and
the diode in the edge portion and the diode in the inner region located inside the edge portion can be driven electrically independently of each other.
5. The light-emitting device according to claim 1 ,
wherein the at least two regions are formed with diodes,
on the other principal surface of the light-emitting element, an electrode is provided over an entirety of the surface, whereas on the one principal surface of the light-emitting element, an electrode is provided only in the edge portion.
6. The light-emitting device according to claim 1 ,
wherein the at least two regions are made distinct by electrode patterns, and
an electrode spacing in the edge portion is smaller than an electrode spacing in the inner region located inside the edge portion.
7. The light-emitting device according to claim 1 , wherein, in the at least two regions, the edge portion has an electrode resistance smaller than that of the inner region located inside the edge portion.
8. The light-emitting device according to claim 1 , wherein, in the at least two regions, the inner region located inside the edge portion has an internal resistance greater than that of the edge portion.
9. The light-emitting device according to claim 1 , wherein, in the at least two regions, the edge portion has a transmissivity of the primary light greater than that of the inner region located inside the edge portion.
10. The light-emitting device according to claim 1 , wherein the light-emitting element is obtained by removing a growth substrate.
11. The light-emitting device according to claim 7 , wherein a thickness of the electrode at the edge portion is greater than a thickness of the electrode in the inner region located inside the edge portion.
12. The light-emitting device according to claim 8 , wherein the inner region located inside the edge portion is subjected to ion implantation.
13. The light-emitting device according to claim 8 , wherein the edge portion is doped with a dopant at a higher concentration than that in the inner region located inside the edge portion.
14. The light-emitting device according to claim 9 , wherein, on the one principal surface of the light-emitting element, a dielectric multilayer film is provided on the edge portion.
15. The light-emitting device according to claim 9 , wherein, on the one principal surface of the light-emitting element, only the edge portion has an uneven structure.