Phosphor and light emitting device using the same
There is provided a phosphor emitting light of high brightness and having high weatherability, which has a composition represented by the following general formula: (M 1 1−y R y ) a MgM 2 b M 3 c O a+2b+(3/2)c X 2 wherein M 1 is at least one element selected from the group consisting of Ca, Sr, Ba, Zn and Mn, M 2 is at least one element selected from the group consisting of Si, Ge and Sn, M 3 is at least one element selected from the group consisting of B, Al, Ga and In, X is at least one element selected from the group consisting of F, Cl, Br and I, R is at least one element selected from the group consisting of rare earth elements with Eu being an inevitable element, and y, a, b and c satisfy the following relationships of 0.0001≦y≦0.3, 7.0≦a<10.0, 3.0≦b<5.0 and 0≦c<1.0.
1. A phosphor having a composition represented by the following general formula:
(M 1 1−y R y ) a MgM 2 b M 3 c O a+2b+(3/2)c X 2
wherein M 1 is at least one element selected from the group consisting of Ca, Sr, Ba, Zn and Mn, M 2 is at least one element selected from the group consisting of Si, Ge and Sn, M 3 is at least one element selected from the group consisting of B, Al, Ga and In, X is at least one element selected from the group consisting of F, Cl, Br and I, R is at least one element selected from the group consisting of rare earth elements with Eu being inevitable element, and y, a, b and c satisfy the following relationships of 0.0001≦y≦0.3, 8.5≦a<9.5, 3.0≦b<5.0 and 0≦c<1.0.
2. A light emitting device comprising a light source and a phosphor which is excited by light emitted from the light source and has a composition represented by the following general formula:
(M 1 1−y R y ) a MgM 2 b M 3 c O a+2b+(3/2)c X 2
wherein M 1 is at least one element selected from the group consisting of Ca, Sr, Ba, Zn and Mn, M 2 is at least one element selected from the group consisting of Si, Ge and Sn, M 3 is at least one element selected from the group consisting of B, Al, Ga and In, X is at least one element selected from the group consisting of F, Cl, Br and I, R is at least one element selected from the group consisting of rare earth elements with Eu being inevitable element, and y, a, b and c satisfy the following relationships of 0.0001≦y≦0.3, 8.5≦a<9.5, 3.0≦b<5.0 and 0≦c<1.0.
3. The phosphor as recited in claim 1 , wherein the phosphor includes Si and a portion of Si is substituted with Ge and/or Sn.
4. The phosphor as recited in claim 1 , wherein the phosphor includes Cl and a portion of Cl is substituted with at least one of F, Br and I.
5. The phosphor as recited in claim 1 , wherein the phosphor includes Eu and a portion of Eu is substituted with at least one element selected from the group consisting of Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm and/or Yb.
6. The phosphor as recited in claim 1 , wherein the phosphor includes Ca and proportions of Ca:Eu of 8.425:0.075 to 8.10:0.40 in molar ratio are employed.
7. The phosphor as recited in claim 1 , wherein the phosphor includes Ca and Mn as essential elements.
8. The phosphor as recited in claim 7 , wherein the amount of Mn is in a range of 0.30 to 0.50 in molar ratio.
9. The phosphor as recited in claim 7 , wherein emission of the phosphor has a chromaticity coordinate in a pentagonal area defined by following five chromaticity coordinates x/y=0.377/0.583, x/y=0.383/0.589, x/y=0.389/0.586, x/y=0.400/0.577 and x/y=0.395/0.575.
10. The light emitting device as recited in claim 2 , wherein the light emitting device has a peak of emission at a wavelength in a range from 240 nm to 520 nm.
11. The light emitting device as recited in claim 2 , wherein the light emitting device has a peak of emission at a wavelength in a range from 320 nm to 480 nm.
12. The light emitting device as recited in claim 2 , wherein the phosphor includes Si and a portion of Si is substituted with Ge and/or Sn.
13. The light emitting device as recited in claim 2 , wherein the phosphor includes Cl and a portion of Cl is substituted with at least one of F, Br and I.
14. The light emitting device as recited in claim 2 , wherein the phosphor includes Eu and a portion of Eu is substituted with at least one element selected from the group consisting of Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm and/or Yb.
15. The light emitting device as recited in claim 2 , wherein the phosphor includes Ca and proportions of Ca:Eu of 8.425:0.075 to 8.10:0.40 in molar ratio are employed.
16. The light emitting device as recited in claim 2 , wherein the phosphor includes Ca and Mn as essential elements.
17. The light emitting device as recited in claim 16 , wherein the amount of Mn is in a range of 0.30 to 0.50 in molar ratio.
18. The light emitting device as recited in claim 17 , wherein emission of the phosphor has a chromaticity coordinate in a pentagonal area defined by following five chromaticity coordinates x/y=0.377/0.583, x/y=0.383/0.589, x/y=0.389/0.586, x/y=0.400/0.577 and x/y=0.395/0.575.
19. A phosphor having a composition represented by the following general formula:
(M 1 1−y R y ) a MgM 2 b M 3 c O a+2b+(3/2)c X 2
wherein M 1 is at least one element selected from the group consisting of Ca, Sr, Ba, Zn and Mn, M 2 is at least one element selected from the group consisting of Si, Ge and Sn, M 3 is at least one element selected from the group consisting of B, Al, Ga and In, X is at least one element selected from the group consisting of rare earth elements with Eu being inevitable element, and y, a, b and c satisfy the following relationships of 0.0001≦y≦0.3, a=7.5, 3.0<b<5.0 and 0≦c<1.0.
20. A light emitting device comprising a light source and the phosphor as recited in claim 19 .