Towards 3-D THz volume inspection for process control

We report on the development of a stepped frequency continuous wave THz imaging system for process control in industrial environments. The system is based on a sparse line array consisting of 12 emitters and 12 heterodyne receivers operating in a frequency range between 75 GHz and 110 GHz. The applied multiple-input and multiple-output technique allows the reconstruction of THz images with 144 virtual pixels per line, while a band-conveyer below the line array provides the required feed motion of the sample for 3-D data acquisition.