Registration and spectral identification of THz images in reflected or transmitted light

The paper presents the results of application of terahertz radiation for detection of traces of explosives on surfaces of objects in reflected light. The process of detection and identification of explosives is based on a recording of interferograms of reflected radiation in spectral range of 0.5 -2.5 THz with help of a Michelson interferometer. The reverse Fourier processing lets to obtain reflection or transmittance spectra and images of objects. Spectral ranges for imaging are chosen by an operator. An installation elaborated for this purpose is described. Specific features of reflection spectra of some organic substances are determined.

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