White phosphors, methods of making white phosphors, white light emitting LEDS, methods of making white light emitting LEDS, and light bulb structures

• US 8,044,419 B2
• Filed: 05/21/2007
• Issued: 10/25/2011
• 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: He, Zhiyi, Basun, Sergei, Yen, William M., Gama, Gennaro J., Wang, Xiao-jun
• Primary Examiner(s): Louie; Wai Sing
• Application Number:
  US12/298,100
• Publication Number:
  US 20090095970A1
• Time in Patent Office: 1,618 Days
• Field of Search: 257/98, 257/451
• US Class Current: 257/98
• 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 composition, comprising:

a white phosphorous composition including;

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 emission 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.

2. The composition of claim 1, 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.

3. The composition of claim 2, wherein P3 provides the white phosphorous composition with a tint in the color of radiation emitted by P3.

20. A ceramic comprising, one or more of the compositions of claims 1 to 19.

4. A composition, comprising:

a white phosphorous composition including;

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 wherein 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 in a red region of the spectrum by the precursor phosphor P1, ε

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

5. The composition of claim 4, wherein P1 is about 95 to 97 mol % of the composition and P2 is about 3 to 5 mol % of the composition.

6. The composition of claim 4, wherein P1 includes SrGa₂S₄:

Eu_a²⁺, wherein “

a”

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

7. The composition of claim 4, wherein P1 includes CaGa₂S₄:

Eu_a²⁺, wherein “

a”

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

8. The composition of claim 4, wherein P1 includes Ca_xSr₁₋

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.

9. The composition of claim 4, wherein P2 includes CaS:

Eu_a²⁺, wherein “

a”

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

10. The composition of claim 4, wherein P2 includes (MgO)₃MgF₂GeO₂:

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

11. The composition of claim 10, wherein b is from about 0.0001 to 0.1.

12. The composition of claim 4, 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%.

13. The composition of claim 12, wherein P3 provides the white phosphorous composition with a tint in the color of radiation emitted by P3.

14. A composition, comprising:

a white phosphorous composition including;

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, and 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.

15. The composition of claim 14, wherein the phosphor emits radiation in the color of P1'"'"'s emission when excited by radiation that stimulates P1.

16. The composition of claim 14, wherein the phosphor emits radiation in the color of P2'"'"'s emission when excited by radiation that stimulates P2.

17. The composition of claim 14, wherein the phosphor emits white light when simultaneously excited by radiation that stimulates P1 and P2.

18. The composition of claim 17, 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%.

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