Abstract

<b>In this study, the resolution of a time-domain terahertz spectrometer for tablet porosity measurements was estimated using two sets of pharmaceutical tablets. One set consisted of tablets with constant thickness and with porosity as a variable. The other set consisted of tablets with variable thickness and only a relatively small change in porosity. The set with constant thickness was used for the calibration of the terahertz (THz) spectrometer for the porosity measurements, and the resolution of the terahertz spectrometer was estimated using the set with different thicknesses and slightly different porosities. It was shown that a time-domain THz spectrometer is a sensitive device that allows monitoring of minute changes in the porosity of pharmaceutical tablets by detecting the time delay of the THz pulse, which is attributable to different refractive indices within the tablet.</b>

Kramers–Kronig analysis on the real refractive index of porous media in the terahertz spectral range

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Comprehensive study of solid pharmaceutical tablets in visible, near infrared (NIR), and longwave infrared (LWIR) spectral regions using a rapid simultaneous ultraviolet/visible/NIR (UVN) + LWIR laser-induced breakdown spectroscopy linear arrays detection system and a fast acousto-optic tunable filter NIR spectrometer

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In-situ evaluation of porosity in thermal barrier coatings based on the broadening of terahertz time-domain pulses: simulation and experimental investigations

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Density-dependent determination of scattering properties of pharmaceutical tablets using coherent backscattering spectroscopy

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Authentication of gold nanoparticle encoded pharmaceutical tablets using polarimetric signatures

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