Terahertz Imaging

Many plastic compounds and synthetics are transparent for terahertz light. This has been used for non-contact analysis and imaging of hidden objects. Researchers at Braunschweig University have used TOPTICA’s DFB lasers to examine the safety covers of airbags [1], demonstrating that terahertz imaging provides an alternative to conventional - destructive - testing methods. In a feasibility study that aimed at security-related applications, researchers at TeraView Ltd. (Cambridge, UK) employed terahertz radiation to depict a ceramic knife blade hidden behind black denim. Other imaging applications include the examination of the water content of foodstuffs inside their air-tight packaging, or the structure of pharmaceuticals.

Compared to X-rays, a distinct advantage of terahertz radiation is its non-ionizing nature. X-rays, due to their high photon energy, are ionizing and therefore pose significant health risks for humans and animals. With terahertz radiation, by contrast, there is no danger of chemical bonds being broken up or the examined material being modified in any way. Terahertz radiation is generally considered biologically innocuous.