FLIR ThermaCAM PM575 - Page 8

[Table of contents]
ThermaCAM™ PM575/595 Operator’s Manual
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7.2.5 Power supply (optional) 48
7.3 Lens data 48
8 Thermographic measurement techniques 49
8.1 Introduction 49
8.2 Emissivity 49
8.2.1 Finding the emissivity of an object 50
8.2.1.1 Using a thermocouple 50
8.2.1.2 Using reference emissivity 50
8.3 Ambient temperature 50
8.4 Distance 50
8.5 Relative humidity 50
9 Theory of thermography 51
9.1 Introduction 51
9.2 The electromagnetic spectrum 51
9.3 Blackbody radiation 52
9.3.1 Planck’s law 52
9.3.2 Wien’s displacement law 54
9.3.3 The Stefan-Boltzmann law 55
9.3.4 Non-blackbody emitters 55
9.4 Infrared semi-transparent materials 57