Surface pinning of disclinations and the stability of bistable nematic storage displays

Abstract

The attraction of bulk singularities in nematic liquid crystals (NLC) to substrate surfaces depends on the existence of discontinuities in surface topography or alignment. The pinning of disclinations governs the stability of certain bistable configuration displays (BCD’s) by providing an energy barrier against their spontaneous detachment. We will discuss the conditions required for attraction or pinning, using model calculations for strength 1/2 disclinations at tilt‐reversal surface junctions. These results are applied to study the stability of (BCD’s) and to devise a scheme for achieving a discrete array of isolated display picture elements (PEL’s) with completely stable boundaries.