FLIR T420 User Manual page 12

Table of contents
30.2 Sharing our knowledge .......................................................... 120
30.3 Supporting our customers....................................................... 120
30.4 A few images from our facilities ................................................ 121
31 Glossary ...................................................................................... 122
32 Thermographic measurement techniques ........................................ 125
32.1 Introduction ........................................................................ 125
32.2 Emissivity............................................................................ 125
32.2.1 Finding the emissivity of a sample .................................. 125
32.3 Reflected apparent temperature............................................... 128
32.4 Distance ............................................................................. 128
32.5 Relative humidity .................................................................. 128
32.6 Other parameters.................................................................. 128
33 History of infrared technology......................................................... 130
34 Theory of thermography................................................................. 133
34.1 Introduction ......................................................................... 133
34.2 The electromagnetic spectrum................................................. 133
34.3 Blackbody radiation............................................................... 133
34.3.1 Planck's law .............................................................. 134
34.3.2 Wien's displacement law.............................................. 135
34.3.3 Stefan-Boltzmann's law ............................................... 136
34.3.4 Non-blackbody emitters............................................... 137
34.4 Infrared semi-transparent materials........................................... 139
35 The measurement formula.............................................................. 140
36 Emissivity tables ........................................................................... 144
36.1 References.......................................................................... 144
36.2 Tables ................................................................................ 144
#T559879; r.18035/18166; en-US
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