18.2.1
Finding the emissivity of a sample
18.2.1.1
Step 1: Determining reflected apparent temperature
Use one of the following two methods to determine reflected apparent temperature:
18.2.1.1.1
Method 1: Direct method
Look for possible reflection sources, considering that the incident angle = reflection angle (a
= b).
10588903;a1
Figure 18.1 1 = Reflection source
1
If the reflection source is a spot source, modify the source by obstructing it using a piece if
cardboard.
10589103;a2
Figure 18.2 1 = Reflection source
2
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Publ. No. T559733_en-US Rev. a571 – ENGLISH (EN) – November 4, 2011
18 – Thermographic measurement techniques