1. A heat source gives the inspected material a thermal excitation.
2. The flow of thermal energy through the material has a direct influence on the temperature development on the object’s surface.
3. If the temperature development on the surface is recorded over a certain period of time with an infrared camera and a mathematical analysis is applied to the acquired data. Then, if the processed data is displayed as an image, this image will provide us with information about the internal structure of the material or about possible defects in it.