Terahertz (THz) Radiation
Definition
Electromagnetic radiation in the frequency range approximately 0.1 to 10 THz (wavelengths 30 micrometres to 3 mm), situated between microwave and mid-infrared; penetrates non-polar, non-conducting materials while being reflected by metals and absorbed by water.
- Frequency range
- About 0.1 to 10 THz
- Wavelength range
- 30 micrometres to 3 mm
- Spectrum position
- Between microwave and mid-infrared
- Blocked by
- Metals and water
- Passes through
- Non-polar, non-conducting materials
Common questions
Why does terahertz imaging fail on wet materials?+
Water molecules absorb strongly across the terahertz band, so damp fabric, tissue or packaging attenuates the signal quickly, which limits how deep the radiation can probe through moisture-bearing evidence.
Is terahertz screening safer than X-ray?+
Yes, because terahertz photons carry far less energy than X-rays, they are non-ionising and do not damage the biological molecules that X-ray exposure can, which is part of why it is explored for body and package screening.
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