WHITE PHOSPHORS, METHODS OF MAKING WHITE PHOSPHORS, WHITE LIGHT EMITTING LEDS, METHODS OF MAKING WHITE LIGHT EMITTING LEDS, AND LIGHT BULB STRUCTURES

• US 20150123536A1
• Filed: 12/29/2014
• Published: 05/07/2015
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: The University of Georgia Research Foundation, Inc.
• Original Assignee: The University of Georgia Research Foundation, Inc.
• Inventors: Yen, William M., He, Zhiyi, Basun, Sergei, Wang, Xiao-jun, Gama, Gennaro J.
• Granted Patent: US 9,157,584 B2
• Time in Patent Office: Days
• US Class Current: 313/503
• CPC Class Codes: C09D 5/22 Luminous paints luminescent compositions C09K11/00
• CPC Class Codes: C09K 11/565 with zinc cadmium
• CPC Class Codes: C09K 11/576 with alkaline earth metals
• CPC Class Codes: C09K 11/592 Chalcogenides
• CPC Class Codes: C09K 11/595 with zinc or cadmium
• CPC Class Codes: C09K 11/665 with alkali or alkaline earth metals
• CPC Class Codes: C09K 11/7421 with alkaline earth metals
• CPC Class Codes: C09K 11/7701 Chalogenides
• CPC Class Codes: C09K 11/7731 with alkaline earth metals
• CPC Class Codes: C09K 11/7787 Oxides C09K11/7785 takes precedence
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Phosphor compositions, white phosphor compositions, methods of making white phosphor compositions, tinted white phosphor compositions, methods of making tinted white phosphor compositions, LEDs, methods of making LEDs, light bulb structures, paints including phosphor compositions, polymer compositions including phosphor compositions, ceramics including phosphor compositions, and the like are provided.

Claims

1. A structure comprising:

a light source and a phosphor composition disposed on the light source, wherein the light source emits radiation in a range that the phosphor composition absorbs the radiation, and the phosphor composition emits radiation at a wavelength different than the light source.

2. The structure of claim 1, wherein the phosphor composition emits radiation in the white light range of wavelengths.

3. The structure of claim 1, wherein the phosphor composition includes a plurality of phosphors.

4. The structure of claim 1, wherein the light source emits at 440 nm.

5. The structure of claim 1, wherein the phosphor composition is a blend of a phosphor and an epoxy.

6. The structure of claim 1, wherein the phosphor composition includes:

a first phosphor compound (P1) that emits radiation in a specific color of the visible spectrum, and

a second phosphor compound (P2) that emits radiation in a color of the visible spectrum that is complementary to the color emitted by P1, wherein the combined emissions of P1 and P2 is substantially white light,

wherein both P1 and P2 have a characteristic that they each are excited by incident radiation in the same range of wavelengths,

wherein a ratio of P1;

P2 is determined from ε

_P1/ε

_P2=m_P2/m _P1, wherein ε

_P1 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P1, ε

_P2 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P2, and m_P1 and m_P2 denote, respectively, the mass of P1 and P2 in the white phosphor.

7. The structure of claim 6, further comprising a phosphor compound (P3) that emits radiation at a region of the spectrum that tints the white light a second color selected from red, green, purple, blue, and yellow, wherein the concentration of P3 is less than about 10% in mass.

8. The structure of claim 7, wherein P3 provides the white phosphorous composition with a tint in the color of radiation emitted by P3.

9. The structure of claim 1, wherein the phosphor composition includes:

a first phosphor compound (P1) that emits radiation in a red region of the spectrum, and

a second phosphor compound (P2) that emits radiation in a green region of the spectrum,

wherein both P1 and P2 have a characteristic that they each are excited by incident radiation with a wavelength from about 350 to 480 nm, and the combined emission of P1 and P2 is substantially white light,

wherein a ratio of P1;

P2 is determined from ε

_P1/ε

_P2=m_P2/m_P1, wherein ε

_P1 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P1, ε

_P2 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P2, and m_P1 and m_P2 denote, respectively, the mass of P1 and P2 in the white phosphor.

10. The structure of claim 9, wherein P1 is about 95 to 97 mol % of the composition and P2 is about 3 to 5 mol % of the composition

11. The structure of claim 9, wherein P1 includes SrGa₂S₄:

Eu_a²⁺ , wherein “

a”

is a number to yield about 0.1 to 10% Eu doping of P1.

12. The structure of claim 9, wherein P1 includes CaGa₂S₄:

Eu_a²⁺, wherein “

a”

is a number to yield about 0.1 to 10% Eu doping of P1

13. The structure of claim 9, wherein P1 includes Ca_xSr_1-xGa₂S₄:

Eu_a²⁺, wherein “

a”

is a number to yield about 0.1 to 10% Eu doping of P1 and x is greater than 0 and less than about 1.

14. The structure of claim 9, wherein P2 includes CaS:

Eu_a²⁺, wherein “

a”

is a number to yield about 0.1 to 10% Eu doping of P2.

15. The structure of claim 9, wherein P2 includes (MgO)₃MgF₂GeO₂:

Mn_b⁴⁺, wherein b is from about 0.0001 to 0.2.

16. The structure of claim 15, wherein b is from about 0.0001 to 0.1.

17. The structure of claim 9, further comprising a phosphor compound (P3) that emits radiation at a region of the spectrum that tints the white light a second color selected from red, green, purple, blue, and yellow, wherein the concentration of P3 is less than about 10%.

18. The structure of claim 17, wherein P3 provides the white phosphorous composition with a tint in the color of radiation emitted by P3.

19. The structure of claim 1, wherein the phosphor composition includes:

first phosphor compound (P1) that emits radiation in a specific color of the visible spectrum, and

a second phosphor compound (P2) that emits radiation in a color of the visible spectrum that is complementary to the color emitted by P1 wherein the combined emissions of P1 and P2 is substantially white light,

wherein P1 and P2 are excited by incident radiation in different ranges of wavelengths,

wherein a ratio of P1;

P2 is determined from ε

_P1/ε

_P2=m_P2/m_P1, wherein ε

_P1 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P1, ε

_P2 denotes an efficiency of conversion of incident radiation into emitted radiation of a certain color by the precursor phosphor P2, and m_P1 and m_P2 denote, respectively, the mass of P1 and P2 in the white phosphor.

20. The structure of claim 19, wherein the phosphor emits radiation in the color of P1'"'"'s emission when excited by radiation that stimulates P1.

21. The structure of claim 19, wherein the phosphor emits radiation in the color of P2'"'"'s emission when excited by radiation that stimulates P2.

22. The structure of claim 19, wherein the phosphor emits white light when simultaneously excited by radiation that stimulates P1 and P2.

23. The structure of claim 19, further comprising a phosphor compound (P3) that emits radiation at a region of the spectrum that tints the white light a second color selected from red, green, purple, blue, and yellow, wherein the concentration of P3 is less than about 10%.

24. The structure of claim 23, wherein P3 provides the white phosphorous composition with a tint in the color of radiation emitted by P3.