Techniques for introscopy of condense matter in terahertz spectral region

Feasibility study of the introscopy of solids and biological objects using high-power terahertz-free-electron laser radiation was performed. A complete set of quasi-optical elements (beam-splitters, windows, mirrors, zone plates and kinoform lens), detectors (bolometers, piroelectric detectors) and imagers (thermograph, luminescence quenching thermal image plate and thermosensitive visible-light interferometer) for the terahertz spectral region have been developed. Detection of hidden amino acids by means of the terahertz shadowgraphy was demonstrated. Because of strong effect of diffraction, we suggest employment of Toepler and holography schemes for the introscopy of objects in the terahertz spectral region.