White light source
A white light source 1 of an embodiment has color temperature of 2600 [K] or more and less than 3200 [K]. The white light source of the embodiment has a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of 0.16 or more and less than 0.35.
1. A white light source, comprising:
a light-emitting diode; and
a phosphor layer absorbing a light radiated from the light-emitting diode to emit a white light;
the phosphor layer including a blue phosphor of from 30 to 60 mass %, a blue-green phosphor of from 5 to 20 mass %, at least one phosphor selected from a green phosphor and a yellow phosphor of from 3 to 20 mass %, and a red phosphor of from 20 to 50 mass %;
the white light having a color temperature of 2600 [K] or more and less than 3200 [K] and an emission spectrum which has a wavelength region of from 450 to 610 [nm]; and
a ratio of a minimum emission intensity to a maximum emission intensity in the wavelength region being 0.16 or more and less than 0.35.
2. The white light source according claim 1 ,
wherein a difference between the ratio of the minimum emission intensity to the maximum emission intensity in the wavelength region of the emission spectrum and a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of black body radiation at the same color temperature as the white light source is −0.02 or more and +0.02 or less.
3. The white light source according to claim 1 ,
wherein the phosphor layer has a single-layer structure or a stacked structure.
4. The white light source according to claim 1 ,
wherein the blue phosphor is a europium-activated alkaline earth chlorophosphate phosphor,
wherein the blue-green phosphor is a europium-activated strontium aluminate phosphor,
wherein the green or yellow phosphor is at least one selected from a europium and manganese-activated alkaline earth aluminate phosphor, a europium and manganese-activated alkaline earth silicate phosphor, and a europium-activated SiAlON phosphor, and
wherein the red phosphor is at least one selected from a europium-activated lanthanum oxysulfide phosphor, a europium-activated CASN phosphor, and a europium-activated SiAlON phosphor.
5. The white light source according to claim 1 ,
wherein the phosphor layer has an average particle diameter of from 3 to 50 μm.
6. The white light source according to claim 1 ,
wherein an amount of the blue-green phosphor is 13.8 mass % or more, and a total amount of the green phosphor and the yellow phosphor is 4.7 mass % or less.
7. A white light source, comprising:
a light-emitting diode; and
a phosphor layer absorbing a light radiated from the light-emitting diode to emit a white light;
the phosphor layer including a blue phosphor of from 35 to 65 mass %, a blue-green phosphor of from 5 to 25 mass %, at least one phosphor selected from a green phosphor and a yellow phosphor of from 3 to 20 mass %, and a red phosphor of from 15 to 45 mass %;
the white light having a color temperature of 3200 [K] or more and less than 3900 [K] and an emission spectrum which has a wavelength region of from 450 to 610 [nm]; and
a ratio of a minimum emission intensity to a maximum emission intensity in the wavelength region being 0.31 or more and less than 0.55.
8. The white light source according claim 7 ,
wherein a difference between the ratio of the minimum emission intensity to the maximum emission intensity in the wavelength region of the emission spectrum and a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of black body radiation at the same color temperature as the white light source is −0.02 or more and +0.02 or less.
9. The white light source according to claim 7 ,
wherein the phosphor layer has a single-layer structure or a stacked structure.
10. The white light source according to claim 7 ,
wherein the blue phosphor is a europium-activated alkaline earth chlorophosphate phosphor,
wherein the blue-green phosphor is a europium-activated strontium aluminate phosphor,
wherein the green or yellow phosphor is at least one selected from a europium and manganese-activated alkaline earth aluminate phosphor, a europium and manganese-activated alkaline earth silicate phosphor, and a europium-activated SiAlON phosphor, and
wherein the red phosphor is at least one selected from a europium-activated lanthanum oxysulfide phosphor, a europium-activated CASN phosphor, and a europium-activated SiAlON phosphor.
11. The white light source according to claim 7 ,
wherein the phosphor layer has an average particle diameter of from 3 to 50 μm.
12. The white light source according to claim 7 ,
wherein an amount of the blue-green phosphor is 15.3 mass % or more, and a total amount of the green phosphor and the yellow phosphor is 8.4 mass % or less.
13. A white light source, comprising:
a light-emitting diode; and
a phosphor layer absorbing a light radiated from the light-emitting diode to emit a white light;
the phosphor layer including a blue phosphor of from 40 to 70 mass %, a blue-green phosphor of from 10 to 30 mass %, at least one phosphor selected from a green phosphor and a yellow phosphor of from 3 to 20 mass %, and a red phosphor of from 10 to 40 mass %;
the white light having a color temperature of 3900 [K] or more and less than 4600 [K] and an emission spectrum which has a wavelength region of from 450 to 610 [nm]; and
a ratio of a minimum emission intensity to a maximum emission intensity in the wavelength region being 0.51 or more and less than 0.76.
14. The white light source according claim 13 ,
wherein a difference between the ratio of the minimum emission intensity to the maximum emission intensity in the wavelength region of the emission spectrum and a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of black body radiation at the same color temperature as the white light source is −0.02 or more and +0.02 or less.
15. The white light source according to claim 13 ,
wherein the phosphor layer has a single-layer structure or a stacked structure.
16. The white light source according to claim 13 ,
wherein the blue phosphor is a europium-activated alkaline earth chlorophosphate phosphor,
wherein the blue-green phosphor is a europium-activated strontium aluminate phosphor,
wherein the green or yellow phosphor is at least one selected from a europium and manganese-activated alkaline earth aluminate phosphor, a europium and manganese-activated alkaline earth silicate phosphor, and a europium-activated SiAlON phosphor, and
wherein the red phosphor is at least one selected from a europium-activated lanthanum oxysulfide phosphor, a europium-activated CASN phosphor, and a europium-activated SiAlON phosphor.
17. The white light source according to claim 13 ,
wherein the phosphor layer has an average particle diameter of from 3 to 50 μm.
18. The white light source according to claim 13 ,
wherein an amount of the blue-green phosphor is 16.4 mass % or more, and a total amount of the green phosphor and the yellow phosphor is 9.1 mass % or less.
19. A white light source, comprising:
a light-emitting diode; and
a phosphor layer absorbing a light radiated from the light-emitting diode to emit a white light;
the phosphor layer including a blue phosphor of from 45 to 75 mass %, a blue-green phosphor of from 10 to 30 mass %, at least one phosphor selected from a green phosphor and a yellow phosphor of from 3 to 20 mass %, and a red phosphor of from 5 to 30 mass %;
the white light having a color temperature of 4600 [K] or more and less than 5700[K] and an emission spectrum which has a wavelength region of from 450 to 610 [nm]; and
a ratio of a minimum emission intensity to a maximum emission intensity in the wavelength region being 0.72 or more and less than 0.97.
20. The white light source according claim 19 ,
wherein a difference between the ratio of the minimum emission intensity to the maximum emission intensity in the wavelength region of the emission spectrum and a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of black body radiation at the same color temperature as the white light source is −0.02 or more and +0.02 or less.
21. The white light source according to claim 19 ,
wherein the phosphor layer has a single-layer structure or a stacked structure.
22. The white light source according to claim 19 ,
wherein the blue phosphor is a europium-activated alkaline earth chlorophosphate phosphor,
wherein the blue-green phosphor is a europium-activated strontium aluminate phosphor,
wherein the green or yellow phosphor is at least one selected from a europium and manganese-activated alkaline earth aluminate phosphor, a europium and manganese-activated alkaline earth silicate phosphor, and a europium-activated SiAlON phosphor, and
wherein the red phosphor is at least one selected from a europium-activated lanthanum oxysulfide phosphor, a europium-activated CASN phosphor, and a europium-activated SiAlON phosphor.
23. The white light source according to claim 19 ,
wherein the phosphor layer has an average particle diameter of from 3 to 50 μm.
24. The white light source according to claim 19 ,
wherein an amount of the blue-green phosphor is 16.7 mass % or more, and a total amount of the green phosphor and the yellow phosphor is 15.2 mass % or less.
25. A white light source, comprising:
a light-emitting diode; and
a phosphor layer absorbing a light radiated from the light-emitting diode to emit a white light;
the phosphor layer including a blue phosphor of from 50 to 80 mass %, a blue-green phosphor of from 10 to 30 mass %, at least one phosphor selected from a green phosphor and a yellow phosphor of from 3 to 20 mass %, and a red phosphor of from 5 to 20 mass %;
the white light having a color temperature of 5700 [K] or more and 6500 [K] or less and an emission spectrum which has a wavelength region of from 450 to 610 [nm]; and
a ratio of a minimum emission intensity to a maximum emission intensity in the wavelength region being 0.79 or more and 0.91 or less.
26. The white light source according claim 25 ,
wherein a difference between the ratio of the minimum emission intensity to the maximum emission intensity in the wavelength region of the emission spectrum and a ratio of a minimum emission intensity to a maximum emission intensity in a wavelength region of from 450 to 610 [nm] on an emission spectrum of black body radiation at the same color temperature as the white light source is −0.02 or more and +0.02 or less.
27. The white light source according to claim 25 ,
wherein the phosphor layer has a single-layer structure or a stacked structure.
28. The white light source according to claim 25 ,
wherein the blue phosphor is a europium-activated alkaline earth chlorophosphate phosphor,
wherein the blue-green phosphor is a europium-activated strontium aluminate phosphor,
wherein the green or yellow phosphor is at least one selected from a europium and manganese-activated alkaline earth aluminate phosphor, a europium and manganese-activated alkaline earth silicate phosphor, and a europium-activated SiAlON phosphor, and
wherein the red phosphor is at least one selected from a europium-activated lanthanum oxysulfide phosphor, a europium-activated CASN phosphor, and a europium-activated SiAlON phosphor.
29. The white light source according to claim 25 ,
wherein the phosphor layer has an average particle diameter of from 3 to 50 μm.
30. The white light source according to claim 25 ,
wherein an amount of the blue-green phosphor is 18.3 mass % or more, and a total amount of the green phosphor and the yellow phosphor is 8.6 mass % or less.