White light-emitting lamp, backlight using same, display and illuminating device
View Patent ↗A white light-emitting lamp ( 1 ) includes a semiconductor light-emitting device such as a LED chip ( 2 ) which has an emission wavelength of 360 nm or more and 440 nm or less, and a light-emitting part including a blue light-emitting phosphor, a green light-emitting phosphor and a red light-emitting phosphor, which emits white light when excited by light from the LED chip ( 2 ). At least one phosphor selected from Eu activated halophosphate phosphors and Eu activated aluminate phosphors is used as the blue light-emitting phosphor, Au and Al activated zinc sulfide phosphor is used as the green light-emitting phosphor, and at least one phosphor selected from Eu and Sm activated lanthanum sulfide phosphors and Cu and Mn activated zinc sulfide phosphors is used as the red light-emitting phosphor.
1. A white light-emitting lamp, comprising:
a semiconductor light-emitting device having an emission wavelength in a range of 360 nm or more and 440 nm or less; and
a light-emitting part, which is excited by light from the semiconductor light-emitting device to emit white light, including a blue light-emitting phosphor which is composed of at least one selected from a europium-activated halophosphate phosphor and a europium-activated aluminate phosphor, a green light-emitting phosphor which is composed of a gold and aluminum-activated zinc sulfide phosphor, and a red light-emitting phosphor which is composed of at least one selected from a europium and samarium-activated lanthanum oxysulfide phosphor and a copper and manganese-activated zinc sulfide phosphor, wherein
the gold and aluminum-activated zinc sulfide phosphor has a composition which is represented by the general formula:
ZnS:Au x ,Al y
where, x and y are numbers meeting 0.0002≦x≦0.0015, 0.0001≦y≦0.0012.
2. The white light-emitting lamp according to claim 1 , wherein the europium and samarium-activated lanthanum oxysulfide phosphor has a composition which is represented by the general formula:
(La 1-a-b ,Eu a ,Sm b ) 2 O 2 S
where, a and b are numbers meeting 0.01≦a≦0.15, 0.0001≦b≦0.03.
3. The white light-emitting lamp according to claim 1 , wherein the copper and manganese-activated zinc sulfide phosphor has a composition which is represented by the general formula:
ZnS:Cu v ,Mn w
where, v and w are numbers meeting 0.0002≦v≦0.001, 0.005≦w≦0.014.
4. The white light-emitting lamp according to claim 1 , wherein the light-emitting part includes at least the europium and samarium-activated lanthanum oxysulfide phosphor as the red light-emitting phosphor.
5. The white light-emitting lamp according to claim 1 , wherein the light-emitting part includes both the europium and samarium-activated lanthanum oxysulfide phosphor and the copper and manganese-activated zinc sulfide phosphor as the red light-emitting phosphor.
6. The white light-emitting lamp according to claim 5 , wherein a mass ratio of the europium and samarium-activated lanthanum oxysulfide phosphor to the copper and manganese-activated zinc sulfide phosphor is in a range of 8:2 to 3:7.
7. The white light-emitting lamp according to claim 1 , wherein the europium-activated halophosphate phosphor has a composition which is represented by the general formula:
(M1 1-c ,Eu c ) 10 (PO 4 ) 6 .Cl 2
where, M1 denotes at least one element selected from Mg, Ca, Sr and Ba, and c is a number meeting 0.005≦c≦0.03.
8. The white light-emitting lamp according to claim 1 , wherein the europium-activated aluminate phosphor has a composition which is represented by the general formula:
m (M2 1-d ,Eu d )O. n Al 2 O 3
where, M2 denotes at least one element selected from Mg, Ca, Sr, Ba and Zn, and d, m and n are numbers meeting 0.05≦d≦0.3, 0<m, 0<n, 0.2≦m/n≦1.5.
9. The white light-emitting lamp according to claim 1 , wherein the light-emitting part has a resin layer in which the blue light-emitting phosphor, the green light-emitting phosphor and the red light-emitting phosphor are dispersed.
10. The white light-emitting lamp according to claim 9 , wherein the blue light-emitting phosphor, the green light-emitting phosphor and the red light-emitting phosphor have an average particle diameter of 7 μm or more as their mixture.
11. The white light-emitting lamp according to claim 9 , wherein the blue light-emitting phosphor, the green light-emitting phosphor and the red light-emitting phosphor are previously integrated into one body by a binder.
12. The white light-emitting lamp according to claim 11 , wherein the blue light-emitting phosphor, the green light-emitting phosphor and the red light-emitting phosphor have an average primary particle diameter of 7 μm or more before their integration and an average secondary particle diameter of 10 μm or more after their integration.
13. The white light-emitting lamp according to claim 1 , wherein the semiconductor light-emitting device has a light emitting diode or a laser diode.
14. A backlight, comprising the white light-emitting lamp according to claim 1 .
15. A display, comprising:
a backlight provided with the white light-emitting lamp according to claim 1 ; and
a display unit which is disposed on a side of a light emission surface of the backlight.
16. The display according to claim 15 , wherein the display unit has a transmissive or semi-transmissive liquid crystal display unit.
17. An illuminating device, comprising the white light-emitting lamp according to claim 1 .