However, the equidistant
lines, that were clearly visible by AFM in the pure CB7CB
material (Figure 5b), could not be detected in the images of
the mixtures. Instead, focal conics are covered by irregular
defect lines (Figure 5c) similarly as observed for focal conics
in a chiral smectic phase with a long pitch, when the pitch is
partially unwound due to the interactions with the surface