Industrial Quality Control with Fast Terahertz Systems
Non-contact inspection even on fast conveyor belts
- Plastics, paper, ceramics, … are transparent in the THz range
- Terahertz techniques enable 100% inspection in production lines
- Ultrafast methods achieve data rates up to 100 MHz
- Recommended systems: TeraFlash pro, TeraFlash smart
Properties and applications of terahertz waves
Terahertz waves feature unique properties. They pass through many non-conducting materials, including paper, cardboard, plastics, wood, ceramics and composite structures. This opens up a wide field of applications in quality and process control, taking advantage of novel measurement techniques that are inherently safe, fast and contact-free. Inspection systems work either in transmission or reflection, depending on the measurement task.
A promising application is quality control of folded cardboard boxes that are used for pharmaceuticals. European legislation dictates that pharmaceuticals may only be sold with patient information leaflets enclosed. In proof-of-principle measurements, TOPTICA’s researchers have shown that the presence, or absence, of a package insert could be detected unambiguously even for samples moving at more than 20 meters per second.
Fast terahertz systems also lend themselves to the observation of dynamic processes, such as drying or curing of materials. The temporal resolution can even be shorter than 1 µs.
See more in our product videos:
- Review paper: Naftaly, M., et al., Industrial applications of terahertz sensing: State of play, Sensors (2019)
- Publication: M. Yahyapour et al., Fastest thickness measurements with a terahertz time-domain system based on electronically controlled optical sampling; Appl. Sciences (2019)
- Conference Abstract: M. Yahyapour et al., Non-Contact Thickness Measurements with Terahertz Pulses, WCNDT 2016
- Scientific Paper: F. Rettich et al., Field intensity detection of individual terahertz pulses at 80 MHz repetition rate; J Infrared Milli. Terahz. Waves 36:7 (2015)
- Scientific Paper: N. Vieweg et al., Terahertz-time domain spectrometer with 90 dB peak dynamic range; J Infrared Milli. Terahz. Waves 35:10 (2014)
- Scientific Paper: S. Brinkmann et al., Towards Quality Control in Pharmaceutical Packaging: Screening Folded Boxes for Package Inserts, J Infrared Milli. Terahz. Waves (2017)