Spectroscopy solution for counterfeit clothing

The new technique - based on terahertz time-domain spectroscopy - will help customs officers ascertain whether items of clothing are fake, assisting them in the seizure and destruction of fake goods.

This technique, described in Applied Optics, requires the generation of a beam of terahertz radiation, which is a band of electromagnetic radiation that falls between microwaves and infrared light. A sample of fabric is then placed within this beam and the properties of the terahertz waves are detected after passing through the fabric.

The composition and structure of the different types of fabric give rise to different rates of beam scattering and absorption. Different fabrics posses a distinct transmission profile, which gives it a signature that indicates whether or not the fabric in question is counterfeit.

According to a statement, this research examined fabrics made from wool, cotton, linen, silk and mixed fibres, all of which demonstrated distinct terahertz transmission properties.