Many THz systems have very limited portability and mobility due to their large size and sensitivity to vibrations, pressures, and torque loadings. Further, much of the demand for THz technology comes from research, industrial, and military applications where the operator is not expected to have experience in advanced optical systems. For most field applications, especially for defense applications, a mobile, robust, turnkey, miniature, or handheld THz time-domain spectrometer is essential.
Since terahertz (THz) wave spectroscopy has been utilized to detect a number of chemical and explosive materials and related compounds by providing their spectral signatures in the THz frequency range, there is an interest in THz wve spectroscopy as a technique to sense improvised explosive devices. However, due to the severe water vapor attenuation of THz waves in the atmosphere, the reliable sensing range of THz wave spectroscopy has been limited to relatively short distances.