4
0.6
0.1 0.3 0.5 0.2
0.2 0.0 0. tolerance range)
– Most frequent colour temperature at
Zumtobel: 3000 4000 K
– readjustment the course the LED’s
service life
– Temperature-based readjustment keep
the colour temperature constant
– Constant colour temperature during
dimming
Technology used Zumtobel’s LED modules
700
0. This means that different colour
coordinates can have the same CCT.1 0.76
The Lighting Handbook
Colour temperature and CCT
Colour temperature (CT)
– Colour temperature, well light colour,
in warm, neutral and daylight white
– Corresponds colour tines white,
quoted the Correlated Colour
Temperature (CCT) Kelvin (K)
– Colour coordinates the Planckian radiator
(Planckian curve)
– Real light sources often deviate from this:
correlated colour temperature (CCT)
– Judd straight lines: all points these lines
have the same correlated colour tempera-
ture.8
∞
10000
6000
4000 3000 2500
2000 1500
TC(°K)
520
540
560
580
600
620
500
490
480
460
470
380
700
0.0
y
x
0.2 0.6 0.
stableWhite
Invariable colour temperature
– Specific initial colour temperature
(incl.2
0.4 0.0 0.8
∞
10000
6000
4000 3000 2500
2000 1500
TC(°K)
520
540
560
580
600
620
500
490
480
460
470
380
LED technology
.5
0.5
0.9
0.4 0.3 0.1
0.0
y
x
0.7 0.9
0.1
0.8
0.7
0.6 0.6
0.3
0.7 0.3
0.8
0.5 0.4
0.7
0
