  We characterize the director structures in electroconvection patterns of
nematic liquid crystals by means of polarising microscopy. This study was
stimulated by a theory put forward by Rossberg et al. (patt-sol/9701005) who
propose a mechanism for chevron texture formation. We characterize the relation
between the wave vector modulation and in-plane twist modulations of the
director field. In addition to the standard optical setup, a circular analyzer
is used. The results provide new insight into the interplay of director and
wave vector field leading to the chevron texture and fluctuating conductive
rolls. Our experimental results confirm the theoretical predictions.
