Approximate Description of the Three Dimensional Director and Electric Field in a Liquid Crystal Display at a High Voltage01/15/2000
An approximate analytical approach for describing properties of a liquid crystal display associated with a homeotropic to multidomainlike transition for a liquid crystal with a positive dielectricanisotropy was developed. The electrode and surface coating of the display are prepared in such a way that in the absence of an electric field (dark state) the liquid crystal alignment is homeotropic. The bright state corresponds to a situation when a high voltage is applied to the interdigitated electrodes located on both substrates, which causes a director deformation of a multidomain type. Approximate solutions for the three dimensional electric field and director configuration in the case of strong homeotropic anchoring were obtained to describe the bright state. It was found that two different defect structures are possible for the director configuration: one corresponds to a wall defect and the other to two disclination lines. A first order phase transition between the two structures is predicted at a particular value of the voltage. An estimate of this critical voltage is obtained.