Yellow light-emitting halophosphate phosphors and light sources incorporating the same

• US 6,616,862 B2
• Filed: 05/21/2001
• Issued: 09/09/2003
• Est. Priority Date: 05/21/2001
• Status: Expired due to Term

• Current Assignee: Current Lighting Solutions, LLC (f/k/a GE Lighting Solutions, LLC) (American Industrial Partners)
• Original Assignee: General Electric Company
• Inventors: Srivastava, Alok Mani, Comanzo, Holly Ann, Setlur, Anant Achyut
• Primary Examiner(s): Koslow, C. Melissa
• Application Number:
  US09/681,686
• Publication Number:
  US 20030146411A1
• Time in Patent Office: 841 Days
• Field of Search: 252/301.4 P, 252/301.4 F, 252/301.4 H, 313/503, 313/506, 257/98
• US Class Current: 252/301.40P
• CPC Class Codes: C09K 11/7739 with halogens
• CPC Class Codes: C09K 11/774 Borates
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Halophosphate luminescent materials co-activated with europium and manganese ions and having the general formula of (Ca,Sr,Ba,Mg)₅(PO₄)₃:Eu²⁺,Mn²⁺ are disclosed. The inclusion of manganese shifts the peak emission to longer wavelengths and, thus, is beneficial in generating a bright yellow-to-orange light. White-light sources are produced by disposing a halophosphate luminescent material, optionally with a blue light-emitting phosphor, in the vicinity of a near UV/blue LED. Blue light-emitting phosphors that may be used in embodiments of the present inventions are Sr₄Al₁₄O₂₅:Eu²⁺, Sr₆P₆BO₂₀:Eu²⁺, BaAl₈O₁₃:Eu²⁺, (Sr,Mg,Ca,Ba)₅(PO₄)₃Cl:Eu²⁺, and Sr₂Si₃O₆.2SrCl₂:Eu²⁺.

Claims

1. A luminescent material being activated by both europium and manganese and having a composition represent by (Ca_1-x-y-p-qSr_xBa_yMg_zEu_pMn_q)_a(PO₄)₃D, wherein 0≦

x≦

1, 0≦

y≦

1, 0≦

z≦

1, 0<

p≦

0.3, 0<

q≦

0.3, 0<

x+y+z+p+q≦

1, 4.5≦

a≦

5, and D is selected from the group consisting of F, OH, and combinations thereof;

said luminescent material being capable of absorbing electromagnetic radiation that has wavelengths in a range from about 315 nm to about 450 nm and being capable of emitting visible light.

2. The luminescent material of claim 1, wherein both p and q are positive and each is less than about 0.1.

3. The luminescent material of claim 1, wherein a is in a range from about 4.7 to and including 5.

4. The luminescent material of claim 1, wherein both p and q are positive and each is less than about 0.05.

5. The luminescent material of claim 1, wherein a is in a range from about 4.9 to and including 5.

6. A luminescent material being activated by both europium and manganese and having a composition represent by (Ca_1-p-qEu_pMn_q)_a(PO₄)₃F, wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a≦

5;

said luminescent material being capable of absorbing electromagnetic radiation that has wavelengths in a range from about 315 nm to about 450 nm and being capable of emitting visible light.

7. The luminescent material of claim 6, wherein both p and q are positive and each is less than about 0.1.

8. The luminescent material of claim 6, wherein a is in a range from about 4.9 to and including 5.

9. The luminescent material of claim 6, wherein both p and q are positive and each is less than about 0.05.

10. The luminescent material of claim 6, wherein a is in a range from about 4.9 to and including 5.

11. A luminescent material being activated by both europium and manganese and having a composition represent by (Ca_1-p-qEu_pMn_q)_a(PO₄)₃Cl, wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a<

5;

said luminescent material being capable of absorbing electromagnetic radiation that has wavelengths in a range from about 315 nm to about 450 nm and being capable of emitting visible light.

12. The luminescent material of claim 11, wherein both p and q are positive and each is less than about 0.1.

13. The luminescent material of claim 11, wherein a is in a range from about 4.7 to less than about 5.

14. The luminescent material of claim 11, wherein both p and q are positive and each is less than about 0.05.

15. The luminescent material of claim 11, wherein a is in a range from about 4.9 to less than about 5.

16. A light source comprising:

at least one LED that is capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

at least one luminescent material selected from the group of luminescent materials having a general formula of (Ca_1-x-y-p-qSr_xBa_yMg_zEu_pMn_q)_a(PO₄)₃D,

wherein 0≦

x≦

1, 0≦

y≦

1, 0≦

z≦

1, 0<

p≦

0.3, 0<

q≦

0.3, 0<

x+y+z+p+q≦

1, 4.5≦

a≦

5, and D is selected from the group consisting of F, Cl, OH, and combinations thereof;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

17. The light source of claim 16, wherein said LED emits electromagnetic radiation having wavelengths in a range from about 315 nm to about 450 nm.

18. The light source of claim 17, wherein said LED preferably emits electromagnetic radiation having wavelengths in a range from about 350 nm to about 420 nm.

19. The light source of claim 17, wherein said LED preferably emits electromagnetic radiation having wavelengths in a range from about 350 nm to about 400 nm.

20. The light source of claim 16 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, A₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺;

wherein A is selected from the group consisting of Sr, Mg, Ca, Ba, and combinations thereof.

21. A light source comprising:

at least one LED that is capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

a luminescent material having a formula of (Ca_1-p-qEu_pMn_q)_a(PO₄)₃F,

wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a≦

5;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

22. The light source of claim 21 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, (Sr,Mg,Ca,Ba)₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺.

23. A light source comprising:

at least one LED that is capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

a luminescent material having a formula of (Ca_1-p-qEu_pMn_q)_a(PO₄)₃Cl,

wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a≦

5;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

24. The light source of claim 23 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, A₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺;

wherein A is selected from the group consisting of Sr, Mg, Ca, Ba, and combinations thereof.

25. A light source comprising:

a plurality of LEDs, each being capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

at least one luminescent material selected from the group of luminescent materials having a general formula of (Ca_1-x-y-p-qSr_xBa_yMg_zEu_pMn_q)_a(PO₄)₃D, wherein 0≦

x≦

1, 0≦

y≦

1, 0≦

z≦

1, 0<

p≦

0.3, 0<

q≦

0.3, 0<

x+y+z+p+q≦

1, 4.5≦

a≦

5, and D is selected from the group consisting of F, Cl, OH, and combinations thereof;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

26. The light source of claim 25, wherein said plurality of LEDs emit electromagnetic radiation having wavelengths in a range from about 315 nm to about 450 nm.

27. The light source of claim 26 wherein said plurality of LEDs preferably emit electromagnetic radiation having wavelengths in a range from about 350 nm to about 420 nm.

28. The light source of claim 26 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, A₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺;

wherein A is selected from the group consisting of Sr, Mg, Ca, Ba, and combinations thereof.

29. The light source of claim 26 wherein said plurality of LEDs preferably emit electromagnetic radiation having wavelengths in a range from about 350 nm to about 400 nm.

30. A light source comprising:

a plurality of LEDs, each being capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

a luminescent material having a formula of (Ca_1-p-qEu_pMn_q)_a(PO₄)₃F,

wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a≦

5;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

31. The light source of claim 30 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, A₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺;

wherein A is selected from the group consisting of Sr, Mg, Ca, Ba, and combinations thereof.

32. A light source comprising:

a plurality of LEDs, each being capable of emitting electromagnetic radiation having wavelengths in a range from near UV to blue; and

a luminescent material having a formula of (Ca_1-p-qEu_pMn_q)₅(PO₄)₃Cl,

wherein 0<

p≦

0.3, 0<

q≦

0.3, and 4.5≦

a≦

5;

said luminescent material being capable of absorbing said electromagnetic radiation emitted by said LED and emitting light having wavelengths in the visible spectrum.

33. The light source of claim 32 further comprising at least one luminescent material selected from the group consisting of Sr₄Al₁₄O₂₅:

Eu²⁺, Sr₆P₆BO₂₀;

Eu²⁺, BaAl₈O₁₃;

Eu²⁺, A₅(PO₄)₃Cl;

Eu²⁺, and Sr₂Si₃O₆.2SrCl₂;

Eu²⁺;

wherein A is selected from the group consisting of Sr, Mg, Ca, Ba, and combinations thereof.

34. A luminescent material being activated by both europium and manganese and having a composition represent by (Ca_1-x-y-p-qSr_xBa_yMg_zEu_pMn_q)_a(PO₄)₃D, wherein 0≦

x≦

1, 0≦

y≦

1, 0<

z≦

1, 0<

p≦

0.3, 0<

q≦

0.3, 0<

x+y+z+p+q≦

1, 4.5≦

a≦

5, and D is selected from the group consisting of F, Cl, OH, and combinations thereof;

said luminescent material being capable of absorbing electromagnetic radiation that has wavelengths in a range from about 315 nm to about 450 nm and being capable of emitting visible light.