Examination of errors in the measurement of polyethylene pellets in the THz band

A powder mixture of polyethylene and azurite (copper-based natural mineral) was formed into pellets, which were then analyzed using both terahertz time-domain spectroscopy (1 to 3 THz) and Fourier transform infrared spectroscopy (3 to 5 THz). It was found that the spectral variations depended on both the azurite grain size and the kind of equipment used.