Stationary Noise of the Light Scattered By A Polymer-dispersed Liquid-crystal

Room temperature measurements of the stationary noise of the monochromatic light scattered by a polymer-dispersed liquid crystal (PDLC) have been performed in order to get information about the parameters affecting the fluctuation modes within the LC droplets, such as the effective viscosity constant of the anisotropic medium. The power spectra of the scattered light appear to be described in terms of lorentzian functions, whose intensity and cut-off frequency are strongly dependent on both the scattering angle and the electric field across the sample. Hints about the optical-axis configuration within the LC droplets are provided by a thorough analysis of the measured noise. The main discrepancies between the experimental results and the predictions for an infinite nematic LC are pointed out and discussed in terms of the finite size of the LC droplets.