Table of contents
22 Glossary ........................................................................................ 83
23 Thermographic measurement techniques .......................................... 86
23.1 Introduction .......................................................................... 86
23.2 Emissivity.............................................................................. 86
23.2.1 Finding the emissivity of a sample.................................... 86
23.3 Reflected apparent temperature................................................. 89
23.4 Distance ............................................................................... 90
23.5 Relative humidity .................................................................... 90
23.6 Other parameters.................................................................... 90
24 History of infrared technology........................................................... 91
25 Theory of thermography................................................................... 94
25.1 Introduction ........................................................................... 94
25.2 The electromagnetic spectrum................................................... 94
25.3 Blackbody radiation................................................................. 94
25.3.1 Planck’s law ................................................................ 95
25.3.2 Wien’s displacement law................................................ 96
25.3.3 Stefan-Boltzmann's law ................................................. 97
25.3.4 Non-blackbody emitters................................................. 98
25.4 Infrared semi-transparent materials........................................... 100
26 The measurement formula.............................................................. 101
27 Emissivity tables ........................................................................... 105
27.1 References.......................................................................... 105
27.2 Tables ................................................................................ 105
#T559950; r. AD/35720/35720; en-US
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