C. Cramer et al., THE STATIC NEMATIC DIRECTOR FIELD AT ELECTRODE EDGES, Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals, 257, 1994, pp. 99-112
We have investigated planar LC cells with striped electrodes and two t
ypes of surface alignment of the director. Their optical properties ar
e studied by means of polarizing microscopy, and a simple model is pre
sented to determine the twist and tilt deformation of the director fie
ld. The optical patterns are simulated by computing the transmission f
unction of the cell with model director deformations using the 4 x 4 m
atrix formalism. Depending on the director alignment at the surfaces,
different types of inversion walls have been observed. They form struc
tures of a characteristic geometry influencing the optical performance
of LC devices. LC parameters may be calculated from the geometrical p
atterns of the observed defects. Any further attempt to calculate the
exact static two-dimensionally (2D) deformed director fields in struct
ured NLC cells ought to be checked by its consistency with the experim
ental effects reported here.