1. Introduction to the radiancy Technical Advisory Service
and the colour
2008
Technical Advisory Service
Introduction to radiancy and colour

2. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

3. The radiancy Solar radiancy Radiators Close IR Radio waves Long IR
Visible
Long IR

4. The radiancy Type of radiancy Wavelength Gamma rays from 0 to 0,01 nm
X rays
from 0,01 nm to 10 nm
Ultraviolet (UV)
      -   UV C
      -   UV B
      -   UV A
from 10 nm to 380 nm
from 2 nm to 280 m
from 280 nm to 315 nm
from 315 nm to 380 nm
Light
from 380 nm to 780 nm
Infrared (IR)
     - close IR A
IR B
    - long IR C
from 780 nm to 106 nm
from 780 nm to 1400 nm
from 1400 nm to 2500 nm
from 2500 nm to 106 nm
Radio waves
from106 nm to several km
Solar
spectrum

5. The radiancy Radiography Type of radiancy Application - Effect
Gamma rays
X rays
Radiography
Ultraviolet (UV)
Energy
Tanning
Cancer of the skin
Blanching of objects
Light
Infrared (IR)
     - close IR A
IR B
    - long IR C
Energy of the solar radiancy
Energy emitted by objects (radiators)
Radio waves
Radios

6. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

7. UV Light Short infra red
The solar spectrum
Intensity (W/m²)
Energy
1.5
UV Light Short infra red
1.0
0.5
780
2500
Wavelength
(nm)
Introduction to radiancy and colour

8. The solar spectrum UV : 280 to 380 nm  5% energy
Light : 380 to 780 nm  50% energy
Short I.R. : 78O to 2500 nm  45% energy
Introduction to radiancy and colour

9. The solar spectrum Solar constant : 1353 W/m² direct reflective
absorbed
dispersed
direct

10. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

11. The solar spectrum Intensity (W/m²) Wavelength (nm) 1.5 1.0 0.5
Light
Intensity (W/m²)
1.0
0.5
780
2500
Wavelength
(nm)
Introduction to radiancy and colour

12. The ligth

13. The ligth l(nm) 380 400 500 600 700 800 Violet 380 to 462 nm Blue
Green
500 to 577 nm
Yellow
577 to 600 nm
Orange
600 to 625 nm
Red
625 to 780 nm

14. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

15. Light transmission and reflexion (380–780 nm)
tv = LT = transmitted light
incident light
Light LT tv LR rv
Introduction to radiancy and colour

16. Light transmission and reflexion (380–780 nm)
the light transmission depends on :
the transmission’s curve of the product
the reference illuminant
the eye sensibilty

17. Light transmission and reflexion (380–780 nm)
Transmission curve of the product
Single glazing 6 mm 90 80
CLAIR 70
BRONZE 60
GRIS
Transmission (%) 50
AZUR
VERT 40 30
PRIVA BLUE 20 10
280
380
780
1000
2000
2480
Longueur d’onde (nm)

18. Light transmission and reflexion (380–780 nm)
Reference illuminant

19. Light transmission and reflexion (380–780 nm)
Reference lighting up :
A: filament light bulb (automotive)
C65: natural light
D65: natural light (EN 410)

20. Light transmission and reflexion (380–780 nm)
Eye sensitivity

21. Light transmission and reflexion (380–780 nm)
With t(l) = transmission curve of the product S(l) = eye sensitivity E(l) = reference illuminant

22. Light transmission and reflexion (380–780 nm)
Light reflexion
With r(l) = transmission curve of the product S(l) = eye sensitivity
E(l) = reference lighting up

23. Light transmission and reflexion (380–780 nm)
Index of reproduction of colours RD65
This index gives a quantitative evaluation of the difference in color between 8 samples of color-test lit directly by illuminating D65,
and the light coming from same illuminating, transmitted by the glazing

24. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

25. }SF qe qi SF = g = transmitted heat incident heat
Energetic transmission and reflexion (300–2500 nm)
SF = g = transmitted heat
incident heat
Heat
AEae
DET te
}SF ER re qi qe
Introduction to radiancy and colour

26. Energetic equation : DET + EA + ER = 100 %
Energetic transmission and reflexion (300–2500 nm)
re = ER = energetic reflexion
te = DET = direct energetic transmission
ae = EA = energetic absorption
SF = g = solar factor = total energetic transmission
Energetic equation : DET + EA + ER = 100 %
Introduction to radiancy and colour

27. Energetic transmission and reflexion (300–2500 nm)
Clear glazing
100 50
Stopray Safir
Transmission (%)
Wavelength (nm)

28. Energetic transmission and reflexion (300–2500 nm)
Direct energetic transmission
With t(l) = transmission curve of the product E(l) = solar spectrum of reference

29. Energetic transmission and reflexion (300–2500 nm)
Solar factor (monolithic glazing)
For clear glazing, we have hi = 8 W/(m²K) and he = 23 W/(m²K)

30. Energetic transmission and reflexion (300–2500 nm)
he = coefficient of surface heat exchange between the wall and the external environment absorption
hi = coefficient of surface heat exchange between the wall and the interior environment

31. Transmission et réflexion énergétique (300–2500 nm)

32. Energetic transmission and reflexion (300–2500 nm)
Remarks : indexes of the USA standards
SHGC (solar heat gain coefficient) = SFS
SC (shading coefficient) = sS/87
SC sw = DET/87
SC lw = SC – SC sw
Relative Heat Gain: RHG (W/m²) = 630 SC + 7,8 U

33. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

34. Protection of the glass against radiancy
Protection against X rays
Glass with high lead content

35. Protection of the glass against radiancy
Protection against the UV
Laminated glass
TrUV, SPF, Krochman KDF
The less the UV transmission, the less UV penetrate int he building
Caution: no UV transmission is not synonymous with absence of discolouration (blanching)

36. Protection of the glass against radiancy
Protection against the light and lighting of the buildings
Coloured glazings, coated glass TL
The highest the LT, the more light comes into the building. The lighting level of the buildings depends on the LT
 See training «Glass and solar control»

37. Protection of the glass against radiancy
Protection against vision
Opaque, mat, painted, printed glazings …

38. Protection of the glass against radiancy
Protection against short IR and the heat
Ccoloured glass, coated glass
SF, (TrIR)
The lowest the SF, the lowest heat comes into the building. The system of air conditioning of a building depends on the level of SF
 See training «Glass and solar control»

39. Protection of the glass against radiancy
Protection against long IR
Low emissivity glass (Top N, Top NT, Stopray, Planibel G, Sunergy)
Emissivity e, Ug
The heating system depends on the level of insulation of the building
 See training «Glass and thermal insulation»

40. Protection of the glass against radiancy
Protection against radio waves
Electrified coated glass

41. Protection of the glass against radiancy

42. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

43. The colour

44. The colour

45. The colour

46. The colour
The colour of an object depends on :
the illuminant which lights the object
the object itself which modifies by transmission or reflexion the received light
the eye of the observer and the transfer of the image towards the brain

47. The colour

48. The colour
To quantify a colour, it is thus necessary to know :
the spectrum of energy emitted by the source of light
the spectrum of transmission or reflexion of the object
the response of the human eye

49. The colour
Guild & Wright experiment

50. The colour

51. The colour
R, B, V graphic

52. The colour
CIE 1931 colorimetric graphic

53. The colour
Tristimuli X, Y, Z:

54. The colour

55. The colour
Tristimuli X, Y, Z:
Rem: Y = TL
Inconvenience : Are not sufficient to differentiate all the colours.

56. The colour
Trichromaticity coordinates x, y, z:

57. The colour
Trichromaticity coordinates x, y, z:
Only 2 independent coordinates
So we use : x, y, Y = TL

59. The colour
Diagram of trichromaticity CIE 1931:
contains 2 axis x and y
sources A, B, C, D, … according to the used illuminant
graduated wavelengths on the border = dominant wavelength
the pureness of the tint P = m/n

60. (0,2; 0,5) n m

61. The colour
Diagram of trichromaticity CIE 1931:
Example: A point of coordinates (x, y) = (0,2; 0,5) corresponds to :
a green colour
a l dominant wavelength = 512 nm
a pureness of tint P = 4/10 = 0,4

62. The colour
Diagram of trichromaticity CIE 1931:
Inconveniences :
The inferior side of the graphe corresponds to multichromatics colours  we specify a negative dominant wavelength
This system is not proportional to what the eye can see.

63. The colour

64. The colour
Hunter Lab System :

66. The colour
CIE L*a*b* System:

67. The colour
Système CIE L*a*b*:

68. The colour

69. The colour
Difference of coulour between 2 products :

70. The colour

71. The colour

72. The colour
CIE 1931 and CIE 1964 colorimetric graphic

73. The colour

74. The colour
Summary : Different systems exist :
X, Y, Z
x, y, z
Lab
L*a*b*
CIELCH (L*, C*, h); UCS (Y, u’, v’), …

75. The colour
Summary : In order to characterize a colour at the best, we must specify 5 values :
3 coordinates of colour
1 illuminant
1 angle of observation
Example: Lab, D65, 2°

76. Introduction to the radiancy and the colour
The solar spectrum
The light
Light transmission and reflexion
Energetic transmission and reflexion
Protection of the glass against radiancy
The colour
Conclusion
Introduction to radiancy and colour

77. Conclusion

78. Conclusions

80. Stopray Neutral 50/40 (LR = 15)

81. Conclusion
The perception (colour, level of transmission and reflexion, …) that we have from an object, depends on :
the object
the illuminant
the level on luminosity
its environment (contrast)
A same objet (thus a same glazing) will have a different aspect depending on its location, the time of the day, the surrounding objects, …