Using multiple types of phosphor in combination with a light emitting device

1. A light generating device comprising:

a blue light emitting device that emits blue light with peak wavelength within a range from 460 nanometers (nm) to 480 nm; and,

an epoxy placed over the light emitting device, the epoxy including:

a first type of phosphor; and

a second type of phosphor;

wherein the first type of phosphor, when excited, emits red light; and,

wherein the second type of phosphor is Sr(Ba,Ca)SiO 4 :Eu, which when excited, emits yellow light.

2. A light generating device as in claim 1 additionally comprises one of the following:

a mold compound covering the epoxy;

an optical dome covering the epoxy.

3. A light generating device as in claim 1 :

wherein the first type of phosphor is a red phosphor having one of the following chemical formulas:

CaS:Eu 2+ ,Mn 2+ ,

(Zn,Cd)S:Ag + ,

Mg 4 GeO 5.5 F:Mn 4+ ,

ZnS:Cu + ,

ZnSe:Cu, Cl,

ZnSe 1/2 S 1/2 :Cu,Cl, and

BaSi 7 N 10 :Eu 2+ .

4. A light generating device as in claim 1 additionally comprising:

a second light emitting device; and,

a second epoxy placed over the second light emitting device, the second epoxy including:

the first type of phosphor, and

the second type of phosphor.

5. A light generating device as in claim 1 additionally comprising:

a second light emitting device;

a second epoxy placed over the second light emitting device, the second epoxy including:

the first type of phosphor, and

the second type of phosphor;

a third light emitting device; and,

a third epoxy placed over the third light emitting device, the third epoxy including:

the first type of phosphor, and

the second type of phosphor.

6. A light generating device as in claim 1 , wherein the light emitting device is mounted on one of the following:

a printed circuit board;

a lead frame.

7. A light generating device as in claim 1 , wherein the light emitting device is mounted within a printed circuit board substrate.

8. A light generating device comprising:

emitting means for emitting blue light with peak wavelength within a range from 460 nanometers (nm) to 480 nm; and,

holding means for holding a first type of phosphor and a second type of phosphor adjacent to the emitting means;

wherein the first type of phosphor, when excited, emits red light; and,

wherein the second type of phosphor is Sr(Ba,Ca)SiO 4 :Eu, which when excited, emits yellow light.

9. A light generating device as in claim 8 :

wherein the first type of phosphor is a red phosphor having one of the following chemical formulas:

CaS:Eu 2+ ,Mn 2+ ,

(Zn,Cd)S:Ag + ,

Mg 4 GeO 5.5 F:Mn 4+ ,

ZnS: Cu + ,

ZnSe:Cu, Cl,

ZnSe 1/2 S 1/2 :Cu,Cl,

BaSi 7 N 10 :Eu 2 + .

10. A light generating device as in claim 8 , wherein the emitting means is mounted on one of the following:

a printed circuit board;

a lead frame.

11. A light generating device as in claim 8 , wherein the emitting means is mounted within a printed circuit board substrate.

12. A light generating device comprising:

a blue light emitting device that emits blue light with peak wavelength within a range from 460 nanometers (nm) to 480 nm; and,

an epoxy placed over the light emitting device, the epoxy including:

a first type of phosphor; and

a second type of phosphor;

wherein the first type of phosphor, when excited, emits green light; and,

wherein the second type of phosphor, when excited, emits yellow light.

13. The light generating device of claim 12 , wherein the first type of phosphor is SrGa 2 S 4 :Eu.

14. The light generating device of claim 13 , wherein the first type of phosphor comprises spherical phosphor particles having a mean particle size ranging from about 1 μm to about 30 μm.

15. The light generating device of claim 12 , wherein the first type of phosphor comprises BaGa 4 S 7 :Eu.

16. The light generating device of claim 12 , wherein the first type of phosphor is (Sr,Ca,Ba)(Al,Ga) 2 S 4 :Eu; BaGa 4 S 7 :Eu.