Terahertz time-gated spectral imaging for content extraction through layered structures

  title={Terahertz time-gated spectral imaging for content extraction through layered structures},
  author={Albert Redo-Sanchez and Barmak Heshmat and Alireza Aghasi and Salman Naqvi and Mingjie Zhang and Justin K. Romberg and Ramesh Raskar},
  journal={Nature Communications},
Spatial resolution, spectral contrast and occlusion are three major bottlenecks for non-invasive inspection of complex samples with current imaging technologies. We exploit the sub-picosecond time resolution along with spectral resolution provided by terahertz time-domain spectroscopy to computationally extract occluding content from layers whose thicknesses are wavelength comparable. The method uses the statistics of the reflected terahertz electric field at subwavelength gaps to lock into… 
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