Friedrich-Alexander-Universität Erlangen-Nürnberg

Non-destructive testing in the THz regime

Non-destructive Testing in The THz Regime

In the THz regime between 0.1 and 10 THz a lot of materials that are opaque in the infrared or visible range are transparent for THz radiation. Therefore a lot of non-destructive testing applications are possible.

To get a broadband access to this frequency range we use a so called THz short pulse system. It uses a femtosecond fibre laser which activates a semiconductor material (LT InGaAs/InAlAs). This material emits a THz pulse which is spectrally broad (0.1 – 2.5 THz). In the receiver the same material is used to detect the electric field emitted by the source. To get a time resolved signal the laser pulse hitting the receiver must be delayed. This is done by an increase of the optical path.

Materials of interest are glass fibre reinforced plastics (GFRP) and carbon fibre reinforced plastics (CFRP) as well as all kinds of ceramics. These materials are used in more and more industrial applications in the aviation, automotive or renewable energies industry.

THz Short Pulse System
Mensa Card in visible and THz regime


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