Order parameter of elongated liquid crystal droplets: the method of retrieval by the coherent transmittance data

The inverse light-scattering problem for polymer dispersed liquid crystal film is considered. An optical method to retrieve the tensor order parameter of liquid crystal droplets arranged in a monolayer has been developed. The method is based on the measurement of coherent transmission coefficients of film at normal illumination and comparison with the results of the direct light-scattering problem solution. To find the coherent transmission coefficient, the anomalous diffraction approach, and the approximation of effective refractive indices are used. The dependence of the tensor order parameter on the applied voltage for elongated liquid crystal droplets with the rigidly fixed poles is retrieved by the available experimental data. The obtained results are in correlation with the results of known visual observations of liquid crystal droplet structure and calculations of the director field in droplets with rigidly-fixed poles.