Polymers and terahertz - A perfect match
- Many plastic materials are transparent for terahertz waves
- Pulsed terahertz systems enable non-contact thickness measurements.
- Terahertz imaging reveals hidden defects
- Recommended Systems: TeraFlash, TeraScan
Many polymeric materials appear – to some extent – transparent for terahertz radiation, a property successfully used for contact-free analysis and non-destructive testing. Pulsed terahertz radiation provides information on an object’s thickness, even in multi-layered samples, via time-of-flight techniques: Each layer interface reflects a part of the incident pulse, and the time elapsed between the arrivals of pulse “echoes” from either side is directly proportional to the optical thickness of that layer.
Applications of terahertz radiation for plastic inspection are not limited to just thickness measurements. Scanning a sample, with the help of a terahertz beam, turns a one-dimensional profile into a three-dimensional image that pinpoints sub-surface cracks, voids and delaminations. Spectroscopic techniques determine the absorption coefficient and refractive index of compound materials and reveal their composition and internal structure. The potential of terahertz technologies for quality and process control in the plastic industry seems almost unlimited.
See more in our product videos:
- Brochure: Terahertz Technologies
- Conference Abstract: Yahyapour et al., Non-Contact Thickness Measurements with Terahertz Pulses, WCNDT 2016
- Publication: F. Rettich et al., Field intensity detection of individual terahertz pulses at 80 MHz repetition rate; J Infrared Milli. Terahz. Waves 36:7 (2015)
- Publication: N. Vieweg et al., Terahertz-time domain spectrometer with 90 dB peak dynamic range; J Infrared Milli. Terahz. Waves 35:10 (2014)
- Article: M. Lang, et al., Laser-based terahertz generation & applications, Photonik International (2014)