FLUORESCENT MATERIAL AND LIGHT-EMITTING DEVICE

• US 20090096370A1
• Filed: 12/19/2008
• Published: 04/16/2009
• Est. Priority Date: 10/28/2003
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: TAKASHIMA, Suguru, KINOSHITA, Shinpei, MURAZAKI, Yoshinori, KAMESHIMA, Masatoshi, TAMAKI, Hiroto
• Granted Patent: US 8,169,131 B2
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• 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 11/684 with alkaline earth metals
• CPC Class Codes: C09K 11/703 with zinc or cadmium
• CPC Class Codes: C09K 11/76 also containing phosphorus and halogen, e.g. halophosphates
• CPC Class Codes: C09K 11/7734 Aluminates
• CPC Class Codes: C09K 11/77347 Silicon Nitrides or Silicon Oxynitrides
• CPC Class Codes: C09K 11/7738 with alkaline earth metals
• CPC Class Codes: C09K 11/7739 with halogens
• CPC Class Codes: C09K 11/774 Borates
• CPC Class Codes: C09K 11/7774 Aluminates
• CPC Class Codes: C09K 11/7777 Phosphates
• CPC Class Codes: C09K 11/7787 Oxides C09K11/7785 takes precedence
• CPC Class Codes: C09K 11/7792 Aluminates
• CPC Class Codes: C09K 11/7795 Phosphates
• CPC Class Codes: C09K 11/7797 Borates
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• 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 2224/73265 : 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: H05B 33/14 : characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source

Abstract

A lamp includes a light-emitting body that converts electric energy into light energy and a translucent glass covering the light-emitting body, wherein a phosphor layer is provided on at least inner or outer surface of the translucent glass. The phosphor layer includes a fluorescent material including a first phosphor that at least partially converts energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to a first emission spectrum that is different from the energy, and a second phosphor that at least partially converts the first emission spectrum to a second emission spectrum. Peak wavelengths of the emission spectrum of the first and second phosphors have a relation of complementary colors so that when the light created due to the peak wavelengths of the first and second phosphors are mixed, the resulting light is in the white region.

Claims

1. A lamp comprising a light-emitting body that converts electric energy into light energy and a translucent glass covering the light-emitting body, wherein a phosphor layer is provided on at least the inner or outer surface of the translucent glass, and the phosphor layer comprises a fluorescent material including a first phosphor that at least partially converts energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to a first emission spectrum that is different from the energy, and a second phosphor that at least partially converts the first emission spectrum to a second emission spectrum that is different from the first emission spectrum,

the first phosphor being a light-storing phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1, and

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region.

2. The lamp according to claim 1, wherein the second phosphor, even after the termination of an energy supply by an excitation source, at least partially converts the first emission spectrum.

3. The lamp according to claim 1, wherein the first phosphor and the second phosphor are disposed in the form of layers.

4. The lamp according to claim 1, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein 0, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein O, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

5. The lamp according to claim 1, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

6. A lamp comprising a light-emitting body that converts electric energy into light energy and a translucent glass covering the light-emitting body, wherein a phosphor layer is provided on at least the inner or outer surface of the translucent glass, and the phosphor layer comprises a fluorescent material including a light-storing first phosphor that at least partially absorbs energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to emit phosphorescence, and a second phosphor that partially absorbs the phosphorescence of the first phosphor and converts the wavelength thereof to emit fluorescence,

the fluorescent material being able to emit light having a spectrum created by the combination of the portion of the phosphorescence of the first phosphor not absorbed by the second phosphor and the fluorescence of the second phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1, and

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region.

7. The lamp according to claim 6, wherein the first phosphor and the second phosphor are disposed in the form of layers.

8. The lamp according to claim 6, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein 0, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein 0, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

9. The lamp according to claim 6, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

10. A lamp comprising a light-emitting body that converts electric energy into light energy and a translucent glass covering the light-emitting body, wherein a phosphor layer is provided on at least the inner or outer surface of the translucent glass, and the phosphor layer comprises a fluorescent material including a light-storing first phosphor that at least partially absorbs energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to emit phosphorescence, and a second phosphor that partially absorbs the phosphorescence of the first phosphor and converts the wavelength thereof to emit fluorescence,

the wavelength range of the emission spectrum of the first phosphor at least partially overlapping with the wavelength range of the excitation spectrum of the second phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1, and

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region.

11. The lamp according to claim 10, wherein the first phosphor and the second phosphor are disposed in the form of layers.

12. The lamp according to claim 10, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein O, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein O, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

13. The lamp according to claim 10, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

14. A light-emitting device comprising an LED chip and a fluorescent material that at least partially converts the emission spectrum of the LED chip, wherein the fluorescent material is a fluorescent material including a first phosphor that at least partially converts energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to a first emission spectrum that is different from the energy, and a second phosphor that at least partially converts the first emission spectrum to a second emission spectrum that is different from the first emission spectrum,

the first phosphor being a light-storing phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1,

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region, and

a mixed-color emission created due to the first emission spectrum of the first phosphor and the second emission spectrum of the second phosphor is whitish.

15. The light-emitting device according to claim 14, wherein the first phosphor and the second phosphor are disposed in the form of layers.

16. The light-emitting device according to claim 14, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein O, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein O, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

17. The light-emitting device according to claim 14, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

26. A display unit comprising a display equipped with a plurality of the light-emitting devices cited in claim 14, and a drive circuit electrically connected to the display.

18. A light-emitting device comprising an LED chip and a fluorescent material that at least partially converts the emission spectrum of the LED chip, wherein the fluorescent material is a fluorescent material including a light-storing first phosphor that at least partially absorbs energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to emit phosphorescence, and a second phosphor that partially absorbs the phosphorescence of the first phosphor and converts the wavelength thereof to emit fluorescence,

the fluorescent material being able to emit light having a spectrum created by the combination of the portion of the phosphorescence of the first phosphor not absorbed by the second phosphor and the fluorescence of the second phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1,

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region, and

a mixed-color emission created due to the first emission spectrum of the first phosphor and the second emission spectrum of the second phosphor is whitish.

19. The light-emitting device according to claim 18, wherein the first phosphor and the second phosphor are disposed in the form of layers.

20. The light-emitting device according to claim 18, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein O, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein O, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

21. The light-emitting device according to claim 18, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

27. A display unit comprising a display equipped with a plurality of the light-emitting devices cited in claim 18, and a drive circuit electrically connected to the display.

22. A light-emitting device comprising an LED chip and a fluorescent material that at least partially converts the emission spectrum of the LED chip, wherein the fluorescent material is a fluorescent material including a light-storing first phosphor that at least partially absorbs energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to emit phosphorescence, and a second phosphor that partially absorbs the phosphorescence of the first phosphor and converts the wavelength thereof to emit fluorescence,

the wavelength range of the emission spectrum of the first phosphor at least partially overlapping with the wavelength range of the excitation spectrum of the second phosphor,

wherein the second phosphor is at least one type selected from the group consisting of

(Y_zGd_1-z)₃Al₅O₁₂:

Ce, wherein z is a number that satisfies 0<

z≦

1, and

(A_1-aSm_a)₃A′

₅O₁₂;

Ce, wherein A is at least one type selected from the group consisting of Y, Lu, Sc, La, Gd, Pr and Tb, A′

is at least one type selected from the group consisting of Al, Ga and In, and a is a number that satisfies 0≦

a<

1,

a peak wavelength of the emission spectrum of the first phosphor and a peak wavelength of the emission spectrum of the second phosphor have a relation of complementary colors so that when the light created due to the peak wavelength of the first phosphor and the light created due to the peak wavelength of the second phosphor are mixed, the resulting light is in the white region, and

a mixed-color emission created due to the first emission spectrum of the first phosphor and the second emission spectrum of the second phosphor is whitish.

23. The light-emitting device according to claim 22, wherein the first phosphor and the second phosphor are disposed in the form of layers.

24. The light-emitting device according to claim 22, wherein the first phosphor is at least one type selected from the group consisting of phosphors (1), (3), (5) and (7):

(1) a sulfide-based phosphor wherein S and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr, Zn and Cd are activated by at least one element M′

selected from the group consisting of Cu, Mn, Eu, Cl and Ag;

(3) an aluminate-based phosphor wherein 0, Al, and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho;

(5) a boron-containing aluminate-based phosphor wherein 0, Al, B and at least one element M selected from the group consisting of Mg, Ca, Ba, Sr and Zn are activated by Eu and at least one element Q selected from the group consisting of Pr, Nd, Dy, Er and Ho; and

(7) an oxysulfide-based phosphor wherein O, S and at least one element Ln selected from the group consisting of Y, La, Gd and Lu are activated by Eu and at least one element M selected from the group consisting of Mg, Ti, Nb, Ta and Ga.

25. The light-emitting device according to claim 22, wherein the second phosphor further comprises at least one type selected from the group consisting of phosphors (11), (13) and (15):

(11) a nitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf; and

N are activated by element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu;

(13) an oxynitride-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

at least one element D selected from the group consisting of C, Si, Ge, Sn, Ti, Zr and Hf;

N; and

O are activated by at least one element R selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu; and

(15) a silicate-based phosphor wherein at least one element L selected from the group consisting of Be, Mg, Ca, Sr, Ba and Zn;

O; and

Si are activated by Eu.

28. A display unit comprising a display equipped with a plurality of the light-emitting devices cited in claim 22, and a drive circuit electrically connected to the display.