| Regularly spaced singular lines appear when a cholesteric liquid crystal flows between glass plates inclined at a small wedge angle and remain after the flow ceases. The glass plates are treated to give homeotropic pinning at the surfaces, but the flow effectively creates a region of soft homogeneous pinning slightly away from the surfaces, thus simulating the conditions for development of Grandjean lines in a Cano wedge. Relaxation to the periodic cholesteric configuration produces alternating regions distinguished by parallel and antiparallel connectivity of the director fields between the two surfaces. Computations for a one constant elasticity model give qualitative agreement with experiment on a 3 % solution of cholesteryl oleate in methoxybenzylidene-butylaniline. |
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