Imaging with terahertz waves.

@article{Hu1995ImagingWT,
  title={Imaging with terahertz waves.},
  author={B. B. Hu and Martin C. Nuss},
  journal={Optics letters},
  year={1995},
  volume={20 16},
  pages={
          1716
        }
}
We present what is to our knowledge the first imaging system based on optoelectronic terahertz time-domain spectroscopy. Terahertz time-domain waveforms are downconverted from the terahertz to the kilohertz frequency range, and the waveform for each pixel is frequency analyzed in real time with a digital signal processor to extract compositional information at that point. We demonstrate applications to package inspection and chemical content mapping in biological objects. 

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