Abstract: A method of investigating an object, comprising the steps of: (a) irradiating the object with an optically-generated pulse of electromagnetic radiation, said pulse having a plurality of frequencies in the range from 100 GHz to 100 THz; (b) detecting radiation transmitted and/or reflected from the object to obtain a time domain waveform; (c) repeating steps (a) and (b) for a plurality of points on the object and (d) combining data from step (c) to produce a time domain waveform for the object which has been averaged over the plurality of points.

Abstract: Apparatus and method for detecting an explosive material, involving irradiating an object with a continuous wave (CW) or pulsed beam of Terahertz radiation, preferably in the frequency range of 100 GHz to 100 THz and detecting radiation transmitted and/or reflected from the object. A spectrum is constructed from the detected radiation, which is indicative of a fundamental property of the explosive material. This constructed spectrum is compared with one or more known spectra of explosive materials to determine whether a likeness exists.

Abstract: A method of quantitatively analysing a sample, the method comprising: irradiating the sample with radiation having a plurality of frequencies in the range from 25 GHz to 100 THz; detecting radiation reflected from and/or transmitted by said sample to obtain a frequency domain waveform of said sample; identifying at least one section of interest of said frequency domain wave-form containing spectral features due to intermolecular or other non-intramolecular excitations; and obtaining a value related to the concentration of a component of the sample from the said section.

Abstract: Imaging techniques of pharmaceutical preparations such as tablets are disclosed. The techniques combine the measurement of reflected/transmitted terahertz radiation originating from within the tablet and data analysis localised in frequency and time in order to enable a three dimensional image indicating composition to be obtained.

Abstract: A method for investigating the macromolecular structure of a molecular sample, the method composing irradiating the sample with radiation having a plurality of frequencies in the range of 25 GHz to 20 THz; detecting radiation reflected from and/or transmitted by said sample to obtain a spectra of the sample; and identifying structure in the resultant spectra which arises from intermolecular interactions.