| abstract |
A liquid crystal cell having memory is provided by disposing a liquid crystal material having nematic directors between two substrates which are fabricated to contain an array of singular points. The cell may further include means for detaching singularities such as appropriate electrode arrangements. n These substrate configurations provide multistable configurations of the director alignments because disclinations must be moved, either through the bulk of the liquid crystal material or on the substrate surfaces to switch between the stable configurations. n The switching of the device between stable configurations may be accomplished by the application of electrical fields to the liquid crystal material. n The stable configurations may be optically differentiated by the incorporation of pleochroic dyes into the liquid crystal material or by crossed polarizers. |