Light-emitting device comprising an EU(II)-activated phosphor
View Patent ↗The invention concerns a light emitting device comprising a light emitting structure capable of emitting primary light of a wavelength less then 480 nm and a luminescent screen comprising a phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5≦z≦2.5. The invention also concerns a luminescent screen comprising a phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5≦z≦2.5. The invention also concerns a phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5 <z<2.5.
1. A light emitting device comprising a light emitting structure capable of emitting primary light of a wavelength less then 480 nm and a luminescent screen comprising a phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5<z<2.5.
2. The light emitting device according to claim 1 , wherein the light emitting structure capable of emitting primary light of a wavelength from 450 nm to 480 nm.
3. The light-emitting device according to claim 1 , wherein the light emitting structure is a blue-emitting LED.
4. The light-emitting device according to claim 1 , wherein the phosphor is comprised in a thin film layer.
5. The light emitting device according to claim 1 , wherein the luminescent screen comprises a green phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5<z<2.5 and a red phosphor.
6. The light emitting device according to claim 5 , wherein the red phosphor is selected from the group of (Sr 1-x-y Ba x Ca y )S:Eu wherein 0≦x<1 and 0≦y<1; CaS:Ce,Cl; Li 2 Sr SiO 4 :Eu; (Sr 1-x Ca x )SiO 4 :Eu wherein 0≦x<1; (Y 1-x Gd x ) 3 (Al 1-y Ga y ) 5 O 12 ;Ce wherein 0≦x<1 and 0≦y<1 and (Sr 1-x-y Ba x Ca y ) 2 Si 5 N 8 :Eu wherein 0≦x<1 and 0≦y<1.
7. The light-emitting device according to claim 1 , wherein the device is a lamp.
8. A luminescent screen comprising a phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5<z<2.5.
9. A phosphor of general formula (Sr 1-a-b Ca b Ba c Mg d Zn e )Si x N y O z :Eu a , wherein 0.002≦a≦0.2, 0.0≦b≦0.25, 0.0≦c≦0.25, 0.0≦d≦0.25, 0.0≦e≦0.25, 1.5≦x≦2.5, 1.5≦y≦2.5 and 1.5<z<2.5.
10. A phosphor according to claim 9 , wherein 1.9≦x≦2.1, 1.9≦y≦2.1 and 1.9<z<2.1.
11. A phosphor according to claim 9 , of general formula Sr 1-a Si 2 N 2 O 2 :Eu a .