On the THz Characterization of Dielectric Objects in the Scope of Fire Detection

This scientific paper is an outcome of the MARIE project (for more information, see trrmarie.de) M05. The project M05 focuses on advancing the capabilities of high-resolution terahertz imaging and material characterization in the application area of fire detection, safety and nondestructive testing. In the first phase, the project achieved progress in sub-millimeter imaging and permittivity estimation, focusing on the influence of surface roughness and multilayered artificial objects. Building on these results, the second phase extended the research to include 3D synthetic aperture imaging and characterization of pyrolyzed objects, subsurface analysis of pyrolyzed layers, and passive THz imaging of hidden hotspots. If the project enters its third phase, the focus will shift to developing fine-resolution 3D material maps of complexly shaped surfaces and subsurfaces, with a target resolution of less than 200 µm.