Nondestructive testing of wood based on 120GHz FMCW terahertz radar

Terahertz waves are capable of non-destructive detecting the structural information and evaluting structural integrity of wood. In this paper, leveraging the high penetration and nondestructive characteristics of terahertz waves, a 120GHz frequency-modulated continuous terahertz wave imaging system was employed to examine the wood samples. The results revealed that terahertz surface imaging can intuitively depict the light and dark textures on the surface of the wood. Furthermore, terahertz waves can penetrate wood, capturing a two-dimensional terahertz image of the interface between the wood and metal plate, and clearly identifying defects with distinct features within the figures.