General Time Domain Analysis of T.D.S. Data: Application to Liquid Crystals

In this paper, an automatic two-channel Time-Domain Spectroscopy (T.D.S.) system is reported. The data analysis is achieved in "real time" by using a numerical method without prior assumptions as to the form of the incident voltage pulse form or to the physical relaxation mechanisms. Two cases are treated: the lumped capacitance and the coaxial line. The method is applied to investigate the dielectric behavior of liquid crystals with the help of original cells requiring very small sample volume. With great reductions in time and efforts, the results deduced with this T.D.R. system are in very good agreement with those previously obtained by classical frequency-domain measurements.