1) William Thompson Kelvin invented the Kelvin temperature scale which has absolute zero as its low endpoint and uses degrees Celsius to measure temperature above absolute zero. 2) Kelvin observed that as a carbon block was heated, its color changed, progressing through the colors of the visible light spectrum from red to higher temperatures. 3) A blackbody is an idealized object that absorbs all electromagnetic radiation regardless of frequency or angle of incidence.

1. ‫رنگ‬ ‫حرارت‬ ‫درجه‬
Color Temperature
9/12/2019 Knowledge isn’t power until it is applied, we learn you to apply. 1
BY: M.KEHTARI
ASNT NDT Level III

2. KELVIN COLOR TEMPERATURE
William Thompson Kelvin was a
19th century physicist and
mathematician who invented a
temperature scale that had
absolute zero as its low endpoint.
In physics, absolute zero is a very
cold temperature, the coldest
possible, at which no heat exists
and kinetic energy (movement)
ceases.
Absolute zero is = 273° C,
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3. KELVIN Observation
By heating a block of carbon Kelvin
observed that as the temperature
increased, the color is change too.
So,
The color temperatures started at
the red end of the spectrum and as
his carbon block got hotter, more
colors were observed.
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4. Blackbody
A black body or blackbody is an
idealized physical body that absorbs
all incident electromagnetic
radiation, regardless of frequency or
angle of incidence.
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5. Color Temperature
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6. The right light colour
Usually a neutral white with about 5000–6000 K is chosen, as this is
most similar to sunlight (neutral white). Our eyes perceive this light
colour as accustomed and the human being reacts neutrally.
If the light colour is too warm, this can lead to premature signs of
fatigue in the inspector.
A light colour that is too cold also appears to be unfamiliar or annoying.
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7. ‫سوال‬ ‫یک‬
‫باید‬ ‫ویوور‬ ‫برای‬ ‫که‬ ‫نوری‬ ‫رنگ‬ ‫کلوین‬ ‫درجه‬
‫باشه؟‬ ‫باید‬ ‫چند‬ ‫بشه‬ ‫استفاده‬
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8. ‫فراوان‬ ‫امتنان‬ ‫و‬ ‫سپاس‬ ‫با‬
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