Industrial radome inspection with terahertz waves

We report on the realization of a 3D terahertz imaging system for industrial radome inspection. The system has been designed to be operated within a machining center for radome manufacturing. In order to provide the required flexibility in respect to image resolution and penetration depth, we developed a system, which combines two frequency-modulated continuous-wave terahertz sensing units, operating in adjacent frequency ranges, from 70 to 110 GHz and from 110 to 170 GHz, respectively. The collinear arrangement of the measurement paths does not only allow to simultaneously gather terahertz images in two different frequency ranges, but also to perform data fusion for additional images with increased depth resolution.