| Infrared thermal wave nondestructive detection method is based on the thermal wave theory. Using different heat source to heat the detected material actively, different medium of the material's surface, subsurface physical property and boundary conditions will change the thermal wave's conduction, and then the change will be shown on the surface's temperature field. Through the constantly record of the surface temperature field by infrared detector, and the thermograph series processing, the information about the material and the subsurface structure are attained. While, using infrared thermal wave nondestructive detection method with pulse light heating source, for some detected samples with low emissivity or polluted by soil, glue during manufacturing, or corrupted, all of those complicated surface conditions will effect the light absorption and infrared radiance. In some degrees, it will effect the correct detection of subsurface conditions and interior defects.In this work, through some simulated artifactitious surface conditions and the experiment data analyse to make some initial arithmetic and programs of thermal images processing, some methods of elimination and reduction surface influences are discussed.The main work includes: given the different thickness of paint on the surface of metal and nonmetal flat bottom holes samples, seek the rule of different thickness to the signal reconstruction fit coefficients, and give the arithmetic in theory to reduce the surface paint influence. For the samples' surface heating nonuniformity, the materials' complicated surface conditions and environmental effects to the detection results during the experiment, this paper brings forward the differential thermograph, ratio signals thermograph, pulse phase thermograph and other image processing methods. In addition, the arithmetic and processes are realized in Matlab or VC++ in self developed software.
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