Illumination method and light-emitting device

• US 9,305,970 B2
• Filed: 03/04/2014
• Issued: 04/05/2016
• Est. Priority Date: 09/02/2011
• Status: Active Grant

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Horie, Hideyoshi
• Primary Examiner(s): Lee, Kyoung
• Assistant Examiner(s): Mehta, Ratisha
• Application Number:
  US14/196,662
• Publication Number:
  US 20140183578A1
• Time in Patent Office: 763 Days
• US Class Current: 1/1
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/28 containing only elements of Group II and Group VI of the Periodic Table
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• 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: H05B 33/02 Details
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback

Abstract

To provide an illumination method and a light-emitting device which are capable of achieving, under an indoor illumination environment where illuminance is around 5000 lx or lower when performing detailed work and generally around 1500 lx or lower, a color appearance or an object appearance as perceived by a person, will be as natural, vivid, highly visible, and comfortable as though perceived outdoors in a high-illuminance environment, regardless of scores of various color rendition metric. Light emitted from the light-emitting device illuminates an object such that light measured at a position of the object satisfies specific requirements. A feature of the light-emitting device is that light emitted by the light-emitting device in a main radiant direction satisfies specific requirements.

Claims

1. An illumination method comprising:

illuminated objects preparation step of preparing illuminated objects; and

an illumination step of illuminating the objects by light emitted from light-emitting devices, wherein

in the illumination step, when light emitted from the light-emitting devices illuminate the objects, the objects are illuminated so that the light measured at a position of the objects satisfies (1), (2), and (3) below;

(1) a distance D_uvSSL from a black-body radiation locus as defined by ANSI C78.377 of the light measured at the position of the objects satisfies −

0.0325≦

D_uvSSL≦

−

0.0075;

(2) if an a* value and a b* value in CIE 1976 L*a*b* color space of 15 Munsell renotation color samples from #01 to #15 listed below when mathematically assuming illumination by the light measured at the position of the objects are respectively denoted by a*_nSSL and b*_nSSL (where n is a natural number from 1 to

     15), and

if an a* value and a b* value in CIE 1976 L*a*b* color space of the 15 Munsell renotation color samples when mathematically assuming illumination by a reference light that is selected according to a correlated color temperature T_SSL (K) of the light measured at the position of the objects are respectively denoted by a*_nref and b*_nref (where n is a natural number from 1 to

     15), then each saturation difference Δ

C_n satisfies

−

2.7≦

Δ

C_n≦

18.6 (where n is a natural number from 1 to

     15),

an average saturation difference represented by formula (1) below satisfies formula (2) below and

2. The illumination method according to claim 1, wherein

if a spectral power distribution of the light measured at the position of the objects is denoted by φ

_SSL (λ

), a spectral power distribution of the reference light that is selected according to T_SSL (K) of the light measured at the position of the objects is denoted by φ

_ref (λ

), tristimulus values of the light measured at the position of the objects are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light measured at the position of the object are denoted by (X_ref, Y_ref, Z_ref),

a normalized spectral power distribution S_SSL (λ

) of the light measured at the position of the objects, a normalized spectral power distribution S_ref (λ

) of the reference light that is selected according to T_SSL (K) of the light measured at the position of the objects, and a difference Δ

S (λ

) between the normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

)

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range from 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 exists on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (3) below of the light measured at the position of the objects satisfies −

280≦

A_cg≦

−

26

[Expression 3]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+S(λ

)dλ

 

 

(3).

3. The illumination method according to claim 1, wherein

if a spectral power distribution of the light measured at the position of the objects is denoted by φ

_SSL (λ

), a spectral power distribution of the reference light that is selected according to T_SSL (K) of the light measured at the position of the objects is denoted by φ

_ref (λ

), tristimulus values of the light measured at the position of the objects are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light measured at the position of the objects are denoted by (X_ref, Y_ref, Z_ref), and

if a normalized spectral power distribution S_SSL (λ

) of the light measured at the position of the objects, a normalized spectral power distribution S_ref (λ

) of the reference light that is selected according to T_SSL (K) of the light measured at the position of the objects, and a difference Δ

S (λ

) between the normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

) and moreover

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range from 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 does not exist on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (4) below of the light measured at the position of the object satisfies −

280≦

A_cg≦

−

26

[Expression 4]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+∫

₅₉₀⁷⁸⁰Δ

S(λ

)dλ

 

 

(4).

4. The illumination method according to claim 1, wherein

a luminous efficacy of radiation K (lm/W) in a wavelength range from 380 nm 780 nm as derived from the spectral power distribution φ

_SSL (λ

) of light measured at the position of the object satisfies

180 (lm/W)≦

K (lm/W)≦

320 (lm/W).

5. The illumination method according to claim 1, wherein each of the absolute value of the difference in hue angles |Δ

h_n| satisfies

0.003≦

|Δ

h_n|≦

8.3 (degrees) (where n is a natural number from 1 to

     15).

6. The illumination method according to claim 1, wherein the average saturation difference represented by the general formula (1) satisfies formula (2)′

below

7. The illumination method according to claim 1, wherein each of the saturation difference Δ

C_n satisfies

−

2.4≦

Δ

C_n≦

16.8 (where n is a natural number from 1 to

     15).

8. The illumination method according to claim 1, wherein the difference |Δ

C_max−

Δ

C_min| between the maximum saturation difference value and the minimum saturation difference value satisfies

3.4≦

(|Δ

C_max−

Δ

C_min|)≦

17.8.

9. The illumination method according to claim 1, wherein

the distance D_uvSSL from a black-body radiation locus of the light measured at the position of the objects satisfies

−

0.0250≦

D_uvSSL≦

−

0.0100.

10. The illumination method according to claim 2, wherein the index A_cg represented by the formula (3) or (4) satisfies

−

253≦

A_cg≦

−

29.

11. The illumination method according to claim 1, wherein

the luminous efficacy of radiation K (lm/W) in a wavelength range from 380 nm to 780 nm as derived from the spectral power distribution φ

_SSL (λ

) of the light measured at the position of the objects satisfies

210 (lm/W)≦

K (lm/W)≦

288 (lm/W).

12. The illumination method according to claim 1, wherein the correlated color temperature T_SSL (K) of the light measured at the position of the objects satisfies

2550 (K)≦

T_SSL (K)≦

5650 (K).

13. The illumination method according to claim 1, wherein illuminance at which the objects are illuminated is 150 lx to 5000 lx.

14. The illumination method according to claim 1, wherein the light-emitting devices comprise a semiconductor light-emitting element as a light-emitting element and emit light emitted from one to six light-emitting elements including the light emitted by the semiconductor light-emitting element.

15. The illumination method according to claim 14, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 380 nm or longer and shorter than 495 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is from 2 nm to 45 nm.

16. The illumination method according to claim 15, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm.

17. The illumination method according to claim 15, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 420 nm or longer and shorter than 455 nm.

18. The illumination method according to claim 15, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 455 nm or longer and shorter than 485 nm.

19. The illumination method according to claim 14, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 495 nm or longer and shorter than 590 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is 2 nm to 75 nm.

20. The illumination method according to claim 14, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 590 nm or longer and shorter than 780 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is 2 nm to 30 nm.

21. The illumination method according to claim 14, wherein the semiconductor light-emitting element is created on any substrate selected from the group consisting of a sapphire substrate, a GaN substrate, a GaAs substrate, and a GaP substrate.

22. The illumination method according to claim 14, wherein the semiconductor light-emitting element is fabricated on a GaN substrate or a GaP substrate and a thickness of the substrate is 100 μ

m to 2 mm.

23. The illumination method according to claim 14, wherein the semiconductor light-emitting element is fabricated on a sapphire substrate or a GaAs substrate and the semiconductor light-emitting element is removed from the substrate.

24. The illumination method according to claim 14, comprising a phosphor as a light-emitting element.

25. The illumination method according to claim 24, wherein the phosphor includes one to five phosphors each having different emission spectra.

26. The illumination method according to claim 24, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 380 nm or longer and shorter than 495 nm and a full-width at half-maximum of 2 nm to 90 nm.

27. The illumination method according to claim 26, wherein the phosphor includes one or more types of phosphors selected from the group consisting of a phosphor represented by general formula (5) below, a phosphor represented by general formula (5)′

below, (Sr,Ba)₃MgSi₂O₈;

Eu²⁺, and (Ba,Sr,Ca,Mg)Si₂O₂N₂;

Eu

(Ba,Sr,Ca)MgAl₁₀O₁₇;

Mn,Eu 

 

(5)

Sr_aBa_bEu_x(PO₄)_cX_d 

 

(5)′

(in the general formula (5)′

, X is Cl, in addition, c, d, and x are numbers satisfying 2.7≦

c≦

3.3, 0.9≦

d≦

1.1, and 0.3≦

x≦

1.2, moreover, a and b satisfy conditions represented by a+b=5−

x and 0≦

b/(a+b)≦

0.6).

28. The illumination method according to claim 24, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 495 nm or longer and shorter than 590 nm and a full-width at half-maximum of 2 nm to 130 nm.

29. The illumination method according to claim 28, wherein the phosphor includes one or more types of phosphors selected from the group consisting of Si₆₋

zAl_zO_zN<sub>8−

z</sub>;

Eu (where 0<

z<

4.2), a phosphor represented by general formula (6) below, a phosphor represented by general formula (6)′

below, and SrGaS₄;

Eu²⁺

(Ba_aCa_bSr_cMg_dEu_x)SiO₄ 

 

(6)

(In the general formula (6), a, b, c, d and x satisfy a+b+c+d+x=2, 1.0≦

a≦

2.0, 0≦

b<

0.2, 0.2≦

c≦

0.8, 0≦

d<

0.2, and 0<

x≦

0.5)

Ba<sub>1−

x−

y</sub>Sr_xEu_yMg<sub>1−

z</sub>Mn_zAl₁₀O₁₇ 

 

(6)′

(In general formula (6)′

, x, y, and z respectively satisfy 0.1≦

x≦

0.4, 0.25≦

y≦

0.6, and 0.05≦

z≦

0.5).

30. The illumination method according to claim 24, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 590 nm or longer and shorter than 780 nm and a full-width at half-maximum of 2 to 130 nm.

31. The illumination method according to claim 30, wherein the phosphor includes one or more types of phosphors selected from the group consisting of a phosphor represented by general formula (7) below, a phosphor represented by general formula (7)′

below, (Sr,Ca,Ba)₂Al_xSi<sub>5−

x</sub>O_xN<sub>8−

x</sub>;

Eu (where 0≦

x≦

2), Eu_y(Sr,Ca,Ba)<sub>1−

y</sub>;

Al_1+xSi<sub>4−

x</sub>O_xN<sub>7−

x</sub> (where 0≦

x<

4, 0≦

y<

0.2), K₂SiF₆;

Mn⁴⁺, A_2+xM_yMn_zF_n (where A is Na and/or K;

M is Si and Al;

−

1≦

x≦

1 and 0.9≦

y+z≦

1.1 and 0.001≦

z≦

0.4 and 5≦

n≦

7), (Ca,Sr,Ba,Mg)AlSiN₃;

Eu and/or (Ca,Sr,Ba)AlSiN₃;

Eu, and (CaAlSiN₃)<sub>1−

x</sub>(Si₂N₂O)_x;

Eu (where x satisfies 0<

x<

0.5)

(La<sub>1−

x−

y</sub>,Eu_x,Ln_y)₂O₂S 

 

(7)

(in the general formula (7), x and y denote numbers respectively satisfying 0.02≦

x≦

0.50 and 0≦

y≦

0.50, and Ln denotes at least one trivalent rare-earth element among Y, Gd, Lu, Sc, Sm, and Er)

(k−

x)MgO.xAF₂.GeO₂;

yMn⁴⁺ 

 

(7)′

(in the general formula (7)′

, k, x, and y denote numbers respectively satisfying 2.8≦

k≦

5, 0.1≦

x≦

0.7, and 0.005≦

y≦

0.015, and A is calcium (Ca), strontium (Sr), barium (Ba), zinc (Zn), or a mixture consisting of these elements).

32. The illumination method according to claim 14 comprising a phosphor as a light-emitting element, wherein a peak wavelength of an emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm, and the phosphor includes SBCA, β

-SiAlON, and CASON.

33. The illumination method according to claim 14 comprising a phosphor as a light-emitting element, wherein a peak wavelength of an emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm, and the phosphor includes SCA, β

-SiAlON, and CASON.

34. The illumination method according to claim 1, wherein the light-emitting device is any one selected from the group consisting of a packaged LED, an LED module, an LED lighting fixture, and an LED lighting system.

35. The illumination method according to claim 1, which is for residential uses.

36. The illumination method according to claim 1, which is used for exhibition uses.

37. The illumination method according to claim 1, which is used for presentation purposes.

38. The illumination method according to claim 1, which is used for medical uses.

39. The illumination method according to claim 1, which is for work use.

40. The illumination method according to claim 1, which is used inside industrial devices.

41. The illumination method according to claim 1, which is used in interior of transportation.

42. The illumination method according to claim 1, which is used for works of art.

43. The illumination method according to claim 1, which is used foraged persons.

44. A light-emitting device incorporating a light-emitting element, wherein

light emitted from the light-emitting device includes, in a main radiant direction thereof, light whose distance D_uvSSL from a black-body radiation locus as defined by ANSI C78.377 satisfies −

0.0325≦

D_uvSSL≦

−

0.0075, and

if a spectral power distribution of light emitted from the light-emitting device in the radiant direction is denoted by φ

_SSL (λ

), a spectral power distribution of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction is denoted by φ

_ref (λ

), tristimulus values of the light emitted from the light-emitting device in the radiant direction are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction are denoted by (X_ref, Y_ref, Z_ref), and

if a normalized spectral power distribution S_SSL (λ

) of light emitted from the light-emitting device in the radiant direction, a normalized spectral power distribution S_ref (λ

) of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction, and a difference Δ

S (λ

) between these normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

) and

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range of 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 exists on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (1) below satisfies −

280≦

A_cg≦

−

26

[Expression 6]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+S(λ

)dλ

 

 

(1).

46. The light-emitting device according to claim 44, wherein

the light emitted from the light-emitting device in the radiant direction satisfies (1) and (2) below:

(1) if an a* value and a b* value in CIE 1976 L*a*b* color space of 15 Munsell renotation color samples from #01 to #15 listed below when mathematically assuming illumination by the light emitted from the light-emitting device in the radiant direction are respectively denoted by a*_nSSL and b*_nSSL (where n is a natural number from 1 to

     15), and

an a* value and a b* value in CIE 1976 L*a*b* color space of the 15 Munsell renotation color samples when mathematically assuming illumination by a reference light that is selected according to a correlated color temperature T_SSL (K) of the light emitted from the light-emitting device in the radiant direction are respectively denoted by a*_nref and b*_nref (where n is a natural number from 1 to

     15), then each saturation difference Δ

C_n satisfies

−

2.7≦

Δ

C_n≦

18.6 (where n is a natural number from 1 to

     15),

an average saturation difference represented by formula (3) below satisfies formula (4) below and

47. The light-emitting device according to claim 44, wherein

a luminous efficacy of radiation K (lm/W) in a wavelength range from 380 nm to 780 nm as derived from the spectral power distribution φ

_SSL (λ

) of light emitted from the light-emitting device in the radiant direction satisfies

180 (lm/W)≦

K (lm/W)≦

320 (lm/W).

48. The light-emitting device according to claim 46, wherein each of the absolute value of the difference in hue angles |Δ

h_n| satisfies

0.003≦

|Δ

h_n|≦

8.3 (degrees) (where n is a natural number from 1 to

     15).

49. The light-emitting device according to claim 46, wherein the average saturation difference represented by the general formula (3) above satisfies formula (4)′

below

50. The light-emitting device according to claim 46, wherein each of the saturation difference Δ

C_n satisfies

−

2.4≦

Δ

C_n≦

16.8 (where n is a natural number from 1 to

     15).

51. The light-emitting device according to claim 46, wherein the difference |Δ

C_max−

Δ

C_min| between the maximum saturation difference value and the minimum saturation difference value satisfies

3.4≦

(|Δ

C_max−

Δ

C_min|)≦

17.8.

52. The light-emitting device according to claim 44, wherein

a distance D_uvSSL from a black-body radiation locus of the light emitted from the light-emitting device in the radiant direction satisfies

−

0.0250≦

D_uvSSL≦

−

0.0100.

53. The light-emitting device according to claim 44, wherein the index A_cg represented by the formula (1) or (2) above satisfies

−

253≦

A_cg≦

−

29.

54. The light-emitting device according to claim 44, wherein

the luminous efficacy of radiation K (lm/W) in a wavelength range from 380 nm to 780 nm as derived from the spectral power distribution φ

_SSL (λ

) of light emitted from the light-emitting device in the radiant direction satisfies

210 (lm/W)≦

K (lm/W)≦

288 (lm/W).

55. The light-emitting device according to claim 44, wherein the correlated color temperature T_SSL (K) satisfies

2550 (K)≦

T_SSL (K)≦

5650 (K).

56. The light-emitting device according to claim 44, wherein illuminance at which the light emitted from the light-emitting device in the radiant direction illuminates objects is 150 lx to 5000 lx.

57. The light-emitting device according to claim 44, wherein the light-emitting device comprises a semiconductor light-emitting element as a light-emitting element and emits, in the radiant direction, light emitted from one to six light-emitting elements including the light emitted by the semiconductor light-emitting element.

58. The light-emitting device according to claim 57, wherein a peak wavelength of an emission spectrum of the semiconductor light-emitting element is 380 nm or longer and shorter than 495 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is 2 nm to 45 nm.

59. The light-emitting device according to claim 58, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm.

60. The light-emitting device according to claim 58, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 420 nm or longer and shorter than 455 nm.

61. The light-emitting device according to claim 58, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 455 nm or longer and shorter than 485 nm.

62. The light-emitting device according to claim 57, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 495 nm or longer and shorter than 590 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is 2 nm to 75 nm.

63. The light-emitting device according to claim 57, wherein the peak wavelength of the emission spectrum of the semiconductor light-emitting element is 590 nm or longer and shorter than 780 nm and the full-width at half-maximum of the emission spectrum of the semiconductor light-emitting element is 2 nm to 30 nm.

64. The light-emitting device according to claim 57, wherein the semiconductor light-emitting element is fabricated on any substrate selected from the group consisting of a sapphire substrate, a GaN substrate, a GaAs substrate, and a GaP substrate.

65. The light-emitting device according to claim 57, wherein the semiconductor light-emitting element is fabricated on a GaN substrate or a GaP substrate and a thickness of the substrate is 100 μ

m to 2 mm.

66. The light-emitting device according to claim 57, wherein the semiconductor light-emitting element is fabricated on a sapphire substrate or a GaAs substrate and the semiconductor light-emitting element is removed from the substrate.

67. The light-emitting device according to claim 57, comprising a phosphor as a light-emitting element.

68. The light-emitting device according to claim 67, wherein the phosphor includes one to five phosphors each having different emission spectra.

69. The light-emitting device according to claim 67, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 380 nm or longer and shorter than 495 nm and a full-width at half-maximum of 2 nm to 90 nm.

70. The light-emitting device according to claim 69, wherein the phosphor includes one or more types of phosphors selected from the group consisting of a phosphor represented by general formula (5) below, a phosphor represented by general formula (5)′

below, (Sr,Ba)₃MgSi₂O₈;

Eu²⁺, and (Ba,Sr,Ca,Mg)Si₂O₂N₂;

Eu

(Ba,Sr,Ca)MgAl₁₀O₁₇;

Mn,Eu 

 

(5)

Sr_aBa_bEu_x(PO₄)_cX_d 

 

(5)′

(in the general formula (5)′

, X is Cl, in addition, c, d, and x are numbers satisfying 2.7≦

c≦

3.3, 0.9≦

d≦

1.1, and 0.3≦

x≦

1.2, moreover, a and b satisfy conditions represented by a+b=5−

x and 0≦

b/(a+b)≦

0.6).

71. The light-emitting device according to claim 67, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 495 nm or longer and shorter than 590 nm and a full-width at half-maximum of 2 to 130 nm.

72. The light-emitting device according to claim 71, wherein the phosphor includes one or more types of phosphors selected from the group consisting of Si₆₋

zAl_zO_zN<sub>8−

z</sub>;

Eu (where O<

z<

4.2), a phosphor represented by general formula (6) below, a phosphor represented by general formula (6)′

below, and SrGaS₄;

Eu₂,

(Ba_aCa_bSr_cMg_dEu_x)SiO₄ 

 

(6)

in the general formula (6), a, b, c, d, and x satisfy a+b+c+d+x=2, 1.0≦

a≦

2.0, 0≦

b≦

0.2, 0.2≦

c≦

0.8, 0≦

d≦

0.2, and 0≦

x≦

0.5),

Ba<sub>1−

x−

y</sub>Sr_xEu_yMg<sub>1−

z</sub>Mn_zAl₁₀O₁₇ 

 

(6)′

(in the general formula (6)′

, x, y, and z respectively satisfy 0.1≦

x≦

0.4, 0.25≦

y≦

0.6, and 0.05≦

z≦

0.5).

73. The light-emitting device according to claim 67, wherein the phosphor includes a phosphor having an individual emission spectrum, when photoexcited at room temperature, with a peak wavelength of 590 nm or longer and shorter than 780 nm and a full-width at half-maximum of 2 nm to 130 nm.

74. The light-emitting device according to claim 73, wherein the phosphor includes one or more types of phosphors selected from the group consisting of a phosphor represented by general formula (7) below, a phosphor represented by general formula (7)′

below, (Sr,Ca,Ba)₂Al_xSi<sub>5−

x</sub>O_xN<sub>8−

x</sub>;

Eu (where 0≦

x≦

2), Eu_y (Sr,Ca,Ba)<sub>1−

y</sub>;

Al_1+XSi<sub>4−

x</sub>O_xN<sub>7−

x</sub> (where 0≦

x<

4, 0≦

y<

0.2), K₂SiF₆;

Mn⁴⁺, A_2+xM_yMn_zF_n (where A is Na and/or K;

M is Si and Al;

−

1≦

x≦

1 and 0.9≦

y+z≦

1.1 and 0.001≦

z≦

0.4 and 5≦

n×

7), (Ca,Sr,Ba,Mg)AlSiN₃;

Eu and/or (Ca,Sr,Ba)AlSiN₃;

Eu, and (CaAlSiN₃)<sub>1−

x</sub>(Si₂N₂O)_x;

Eu (where x satisfies 0<

x<

0.5)

(La<sub>1−

x−

y</sub>,Eu_x,Ln_y)₂O₂S 

 

(7)

(in the general formula (7), x and y denote numbers respectively satisfying 0.02≦

x≦

0.50 and 0≦

y≦

0.50, and Ln denotes at least one trivalent rare-earth element among Y, Gd, Lu, Sc, Sm, and Er)

(k−

x)MgO.xAF₂.GeO₂;

yMn⁴⁺ 

 

(7)′

(in the general formula (7)′

, k, x, and y denote numbers respectively satisfying 2.8≦

k≦

5, 0.1≦

x≦

0.7, and 0.005≦

y≦

0.015, and A is calcium (Ca), strontium (Sr), barium (Ba), zinc (Zn), or a mixture consisting of these elements).

75. The light-emitting device according to claim 57 comprising a phosphor as a light-emitting element, wherein a peak wavelength of an emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm, and the phosphor includes SBCA, β

-SiAlON, and CASON.

76. The light-emitting device according to claim 57 comprising a phosphor as a light-emitting element, wherein a peak wavelength of an emission spectrum of the semiconductor light-emitting element is 395 nm or longer and shorter than 420 nm, and the phosphor includes SCA, β

-SiAlON, and CASON.

77. The light-emitting device according to claim 44, which is selected from the group consisting of a packaged LED, an LED module, an LED lighting fixture, and an LED lighting system.

78. The light-emitting device according to claim 44, which is used as a residential uses'"'"' device.

79. The light-emitting device according to claim 44, which is used as a exhibition illumination device.

80. The light-emitting device according to claim 44, which is used as a presentation illumination device.

81. The light-emitting device according to claim 44, which is used as a medical illumination device.

82. The light-emitting device according to claim 44, which is used as a work illumination device.

83. The light-emitting device according to claim 44, which is used as an illumination device incorporated in industrial equipment.

84. The light-emitting device according to claim 44, which is used as an illumination device for interior of transportation.

85. The light-emitting device according to claim 44, which is used as an illumination device for works of art.

86. The light-emitting device according to claim 44, which is used as an illumination device for aged persons.

45. A light-emitting device incorporating a light-emitting element, wherein

light emitted from the light-emitting device includes, in a main radiant direction thereof, light whose distance D_uvSSL from a black-body radiation locus as defined by ANSI C78.377 satisfies −

0.0325≦

D_uvSSL≦

−

0.0075, and

if a spectral power distribution of light emitted from the light-emitting device in the radiant direction is denoted by φ

_SSL (λ

), a spectral power distribution of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction is denoted by φ

_ref (λ

), tristimulus values of the light emitted from the light-emitting device in the radiant direction are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction are denoted by (X_ref, Y_ref, Z_ref), and

if a normalized spectral power distribution S_SSL (λ

) of light emitted from the light-emitting device in the radiant direction, a normalized spectral power distribution S_ref (λ

) of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction, and a difference Δ

S (λ

) between these normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

), and

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range of 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 does not exist on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (2) below satisfies −

280≦

A_cg≦

−

26

[Expression 7]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+∫

₅₉₀⁷⁸⁰Δ

S(λ

)dλ

 

 

(2).

87. A design method of a light-emitting device incorporating a light-emitting element, wherein

light emitted from the light-emitting device is configured so as to include, in a main radiant direction thereof, light whose distance D_uvSSL from a black-body radiation locus as defined by ANSI C78.377 satisfies −

0.0325≦

D_uvSSL≦

−

0.0075, and

if a spectral power distribution of light emitted from the light-emitting device in the radiant direction is denoted by φ

_SSL (λ

), a spectral power distribution of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction is denoted by φ

_ref (λ

), tristimulus values of the light emitted from the light-emitting device in the radiant direction are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction are denoted by (X_ref, Y_ref, Z_ref), and

if a normalized spectral power distribution S_SSL (λ

) of light emitted from the light-emitting device in the radiant direction, a normalized spectral power distribution S_ref (λ

) of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction, and a difference Δ

S (λ

) between these normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

) and

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range from 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 exists on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (1) below satisfies −

280≦

A_cg≦

−

26

[Expression 11]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+S(λ

)dλ

 

 

(1).

88. A design method of a light-emitting device incorporating a light-emitting element, wherein

light emitted from the light-emitting device is configured so as to include, in a main radiant direction thereof, light whose distance D_uvSSL from a black-body radiation locus as defined by ANSI C78.377 satisfies −

0.0325≦

D_uvSSL≦

−

0.0075, and

if a spectral power distribution of light emitted from the light-emitting device in the radiant direction is denoted by φ

_SSL (λ

), a spectral power distribution of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction is denoted by φ

_ref (λ

), tristimulus values of the light emitted from the light-emitting device in the radiant direction are denoted by (X_SSL, Y_SSL, Z_SSL), and tristimulus values of the reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction are denoted by (X_ref, Y_ref, Z_ref), and

if a normalized spectral power distribution S_SSL (λ

) of light emitted from the light-emitting device in the radiant direction, a normalized spectral power distribution S_ref (λ

) of a reference light that is selected according to T_SSL (K) of the light emitted from the light-emitting device in the radiant direction, and a difference Δ

S (λ

) between these normalized spectral power distributions are respectively defined as

S_SSL(λ

)=φ

_SSL(λ

)/Y_SSL,

S_ref(λ

)=φ

_ref(λ

)/Y_ref and

Δ

S(λ

)=S_ref(λ

)−

S_SSL(λ

) and

a wavelength that produces a longest wavelength local maximum value of S_SSL (λ

) in a wavelength range from 380 nm to 780 nm is denoted by λ

_R (nm), then a wavelength Λ

4 that assumes S_SSL (λ

_R)/2 does not exist on a longer wavelength-side of λ

_R, and

an index A_cg represented by formula (2) below satisfies −

280≦

A_cg≦

−

26

[Expression 12]

A_cg=∫

₃₈₀⁴⁹⁵Δ

S(λ

)dλ

+∫

₄₉₅⁵⁹⁰(−

Δ

S(λ

))dλ

+∫

₅₉₀⁷⁸⁰Δ

S(λ

)dλ

 

 

(2).