Field-induced orientational transitions in a nematic with chiral dopant

In the nematic cell with chiral dopant and homeotropic anchoring can exist the next one-dimensional distributions of the director: 1) homeotropic, wit h the director normal to the plates: 2) twisted with tilted orientation of the director; 3) twisted with the director parallel to the surfaces. Stabil ity analysis shows that the transitions might occur between these distribut ions. The dimensionless parameters controlling the director field are the r atio of the pitch of the twisted nematic structure to the cell thickness an d ratio of the cell thickness to thr;extrapolation length of the nematic ma terial.