Modelling nematic liquid crystal alignment on asymmetric surface grating structures

Static nematic liquid crystal director configurations have been calculated numerically for alignment over rin asymmetric grooved surface profile. The results demonstrate the existence of a low pretilt regime, where the director field follows the contours of the grating, and a high pretilt regime, where the director field shows a characteristic defect structure. The relative energies of the distorted director field have been calculated for the two regimes. The profile of a real surface has been implemented in the model and the predicted values of the pretilt are commensurate with those measured experimentally.