Terahertz Systems for Security Applications

• Plastics, paper and cardboard are transparent in the THz range.
• Imaging with terahertz waves reveals hidden objects.
• Many explosives and illicit drugs show spectroscopic “fingerprints”.
• Recommended systems: TeraFlash pro, Imaging Extension, TeraFlash smart, TeraScan

Terahertz systems offer a unique combination of imaging and spectroscopic methods. Terahertz waves penetrate materials like plastics, paper and – to some extent – textiles. They can thus reveal the presence of objects e.g. concealed in parcels, and identify the material in question by spectroscopic techniques. Prospective applications include the detection of drugs or explosives in mail envelopes, or the identification of liquids in suspicious bottles.  

Generally, both time-domain and frequency-domain systems have proven suitable for terahertz imaging. Continuous-wave systems – in particular in conjunction with a broadband Schottky receivers – offer inexpensive, yet flexible solutions for researchers who wish to explore the potential of “spectroscopic imaging”. On the other hand, pulsed systems additionally gain depth information and provide 3D-images of the internal structure of an object.