Penetration Depth of Surface Forces Into Nematic Layers

The minima in the curves U th(d) and p/d(d)/U the is the threshold votage. p is the period of the domains, d is the thickness of the cells of the flexoelectric domains in asymmetric anchored MBBA layers permit the determination of the penetration depth of the surface forces generated from the galss plates treated with SiO under vacum evaporation. The value obtained, about 150 μm is in agreement with the results of other authors. The attenuation of these domains near the spacers on the spacers on the other hand allows the determination of the penetration depth of the surface forces generated by the utilized polymer spacers which is about 350 μm. This simple method can be used for all nematics with positive or negative dielectric anisotropy displaying flexoelectirc domains in asymmetric anchored layers.