Laser 2015: Terahertz technologies - a growing market

An imaging forum in Munich reviewed the remarkable progress of terahertz systems, fast developing a new marketplace.

http://optics.org/news/6/6/44

Applications of terahertz-based photonic systems are growing – whether in non-destructive industrial inspection of polymers or in security applications such as testing for hidden drugs or explosives. An optical metrology forum held yesterday at LASER 2015 reviewed a selection of recent developments, which are emerging from the laboratory and making waves in the marketplace. Dr. Joachim Jonuscheit. In a presentation entitled” Terahertz systems for industrial applications”, Dr Joachim Jonuscheit, of the Fraunhofer Institute for Physical Measurement Techniques (IPM), described the two principle sources of terahertz radiation; femtosecond lasers, based on either Ti:Sa of frequency-doubled fiber lasers; and CW diode lasers, with their associated benefits and disadvantages. “For industrial systems you really need fiber-couple d systems,” he said. “Due to their relatively higher stability and flexibility compared with terahertz generators based on free space optics.” Dr Jonuscheit He also acknowledged some examples of the growing range of commercially available and in-research terahertz sources including the GaAs-based TPS Spectra 3000 from Teraview and other recent developments from Advanced Photonix, Hübner, Toptica Photonics, Bakman Technologies, and from his own lab at the Fraunhofer IPM. He concluded, “Terahertz sources are now available from a range of different suppliers applications. Those based on femtosecond lasers generally offer a broader spectrum and are faster, meaning more spectra per second. Whereas those based on CW laser diodes have the advantage of offering higher spectral resolution and are also cheaper.” Applications of terahertz Subsequent presentations reviewed different applications of terahertz technologies, including: Arno Neumeister. Terahaertz Systems for Plastic Pipes by Arno Neumeister, of Inoex, which develops production and operations inspection systems for applications such as pipe-making. He commented, “Ultrasonic systems cannot measure foamcore pipes, for example, but for our terahertz system, the extra layer of air is actually an advantage”; Terehaertz Imaging and Spectroscopy for Security applications by Dr Niklas Waasem, Sales Engineer Hübner. He described the security benefits of a terahertz approach as: “detecting anomalies in postal items [letter bombs/drugs]; and terahertz spectroscopy with our embedded evaluation software allows automatic identification of substances.” The use of terahertz sensors – out of the lab and into the factory, was presented by Phil Taday, head of applications at Teraview, who stated, “Many common materials and living tissues are semi-transparent and have what you could call terahertz fingerprints, permitting them to be imaged, identified, and analyzed. Moreover, the non-ionizing properties of terahertz radiation and the relatively low power levels used, mean that it is safe.”

About the Author

Matthew Peach is a contributing editor to optics.org.