New optical methods to study director orientation in liquid crystals

Summary We report new optical methods useful to investigate the orientational order of nematic liquid crystals. The first one uses a linear optical technique and a variable-thickness cell to get a precise measurement of the anchoring energies at the boundaries. The second one exploits the nonlinear self-phase modulation to evaluate the elastic anisotropy of a nematic liquid crystal. Examples are reported of measurements performed on hybrid aligned liquid crystals. Also with GNSM and CISM, Unità di Cosenza.