Phosphor blends for generating white light from near-UV/blue light-emitting devices

• US 6,685,852 B2
• Filed: 04/27/2001
• Issued: 02/03/2004
• Est. Priority Date: 04/27/2001
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Srivastava, Alok Mani, Comanzo, Holly Ann, Setlur, Anant Achyut, Doxsee, Daniel Darcy
• Primary Examiner(s): KOSLOW, CAROL M
• Application Number:
  US09/681,549
• Publication Number:
  US 20020158565A1
• Time in Patent Office: 1,012 Days
• Field of Search: 257/98, 313/503, 252/301.4 P, 252/301.4 R
• US Class Current: 252/301.40R
• CPC Class Codes: C09K 11/664 Halogenides C09K11/661 takes precedence
• CPC Class Codes: C09K 11/7734 Aluminates
• CPC Class Codes: C09K 11/7738 with alkaline earth metals
• CPC Class Codes: C09K 11/7739 with halogens
• 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: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Phosphor blends are disclosed that are capable of absorbing electromagnetic radiation having wavelengths in the range from about 315 nm to about 480 nm. These blends are mixtures of phosphors selected from the group consisting of Sr₂P₂O₇:Eu²⁺, Mn²⁺, (Ca,Sr,Ba)₅(PO₄)₃(F,Cl,OH):Eu²⁺,Mn²+, 3.5 MgO.0.5MgF₂.GeO₂:Mn⁴⁺, Sr₄Al₁₄O₂₅:Eu²⁺, (Sr,Ba,Ca)₅(PO₄)₃(Cl,OH):Eu²⁺, (Ba,Ca,Sr)₂MgAl₁₆O₂₇:Eu²⁺, and (Ba,Ca,Sr)₂MgAl₁₆O₂₇:Eu²⁺,Mn²⁺. White light sources are obtained by applying a phosphor blend over at least one LED that is capable of emitting electromagnetic radiation in the above-noted wavelength range.

Claims

1. A phosphor blend comprising at least two phosphors selected from the group consisting of (a) Sr₂P₂O₇:

Eu²⁺,Mn²⁺;

(b) (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH);

Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5;

(c) 3.5MgO.0.5MgF₂.GeO₂;

Mn⁴⁺;

(d) (Sr,Ba,Ca)₅(PO₄)₃(Cl,OH);

Eu²⁺;

(e) an europium-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺; and

(f) an europium and manganese co-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺;

said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

2. The phosphor blend of claim 1, wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.

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

4. The phosphor blend of claim 1, wherein said emitted light is white light.

5. The phosphor blend of claim 4, wherein said white light has color coordinates substantially on a black body locus of a CIE chromaticity diagram.

6. The phosphor blend of claim 5, wherein a is in a range from about 4.7 to and including 5.

7. The phosphor blend of claim 1, wherein a is in a range from about 4.9 to and including 5.

8. The phosphor blend of claim 5, wherein a is in a range from about 4.9 to and including 5.

9. A phosphor blend comprising a mixture of (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH):

Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5 and at least one phosphor that is selected from the group consisting of (a) Sr₂P₂O₇;

Eu²⁺,Mn²⁺;

(b) 3.5MgO.0.5MgF₂.GeO₂;

Mn⁴⁺;

(c) Sr₄Al₁₄O₂₅;

Eu²⁺;

(d) (Sr,Ba,Ca)₅(PO₄)₃(Cl,OH);

Eu²⁺;

(e) an europium activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺; and

(f) an europium and manganese co-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺;

said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

10. The phosphor blend of claim 9, wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.

11. The phosphor blend of claim 9, wherein a is in a range from about 4.7 to and including 5.

12. The phosphor blend of claim 9, wherein a is in a range from about 4.9 to and including 5.

13. A phosphor blend comprising a mixture of Sr₂P₂O₇:

Eu²⁺,Mn²⁺ and at least one phosphor that is selected from the group consisting of (a) (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH);

Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5;

(b) 3.5MgO.0.5MgF₂.GeO₂;

Mn⁴⁺;

(c) (Sr,Ba,Ca)₅(PO₄)₃(Cl,OH);

Eu²⁺;

(d) an europium activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺;

(e) an europium and manganese co-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺;

said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

14. The phosphor blend of claim 13, wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.

15. A phosphor blend comprising a mixture of Sr₂P₂O₇:

Eu²⁺,Mn²⁺ and (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH);

Eu²⁺,Mn²⁺;

wherein a is in a range from about 4.5 to and including 5, and said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

16. The phosphor blend of claim 15, wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.

17. The phosphor blend of claim 15, wherein a is in a range from about 4.7 to and including 5.

18. The phosphor blend of claim 15, wherein a is in a range from about 4.9 to and including 5.

19. A phosphor blend comprising a mixture of phosphors having formulas 3.5MgO.0.5MgF₂.GeO₂:

Mn⁴⁺;

Sr₄Al₁₄O₂₅;

Eu²⁺; and

an europium and manganese co-invented aluminate phosphors selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺;

said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

20. The phosphor blend of claim 19 wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.

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;

least one phosphor material selected from the group consisting of (a) (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH);

Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5;

(b) 3.5MgO.0.5MgF₂.GeO₂;

Mn⁴⁺;

(c) (Sr,Ba,Ca)₅(PO₄)₃(Cl,OH);

Eu²⁺;

(d) an europium-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺; and

(e) an europium and manganese co-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺; and

(f) mixtures thereof;

said phosphor 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, wherein said LED emits electromagnetic radiation in a wavelength from about 315 nm to about 480 nm.

23. The light source of claim 21, wherein a is from about 4.7 to and including 5.

24. The light source of claim 21, wherein said LED preferably emits electromagnetic radiation from about 350 nm to about 410 nm.

25. The light source of claim 21, wherein a is from about 4.9 to and including 5.

26. 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 phosphor consisting of a material selected from the group consisting of Sr₂P₂O₇;

Eu²⁺,Mn²⁺, (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH)Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5, and mixtures thereof;

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

27. The light source of claim 26, wherein a is from about 4.7 to and including 5.

28. The light source of claim 26 wherein a is from about 4.9 to and including 5.

29. 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 phosphor consisting of a first material selected from the group consisting of Sr₂P₂O₇;

Eu²⁺,Mn²⁺ and (Ca,Sr,Ba)_a(PO₄)₃(F,Cl,OH)Eu²⁺,Mn²⁺ wherein a is in a range from about 4.5 to and including 5; and

a second, material selected from the group consisting of (a) 3.5MgO0.5MgF₂GeO₂;

Mn⁴⁺;

an europium-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺; and

(c) an europium and manganese co-activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺,Mn²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺.

30. A phosphor blend comprising a mixture of phosphors having a formula of 3.5MgO.0.5MgF₂.GeO₂:

Mn⁴⁺;

(Sr,Ba,Ca)₅(PO₄)₃(Cl,OH);

Eu²⁺; and

an europium activated aluminate phosphor selected from the group consisting of (Ba,Ca,Sr)₂MgAl₁₆O₂₇;

Eu²⁺, (Ba,Ca,Sr)MgAl₁₀O₁₇;

Eu²⁺,Mn²⁺, and (Ba,Ca,Sr)Mg₃Al₁₄O₂₅;

Eu²⁺,Mn²⁺;

said phosphor blend being capable of absorbing electromagnetic radiation having wavelengths in a range from about 315 nm to about 480 nm and emitting light having wavelengths in the visible spectrum.

31. The phosphor blend of claim 30, wherein said phosphor blend absorbs electromagnetic radiation substantially in a wavelength range from about 350 nm to about 410 nm.