A dielectric liquid layer is sandwiched between a pixel substrate and a counter substrate, at least one of which is a transparent. The dielectric liquid layer is made from a liquid that is macroscopically isotropic and transparent, but has clusters microscopically, the clusters being agglomerations in each of which liquid crystal molecules are aligned in short distance order. Because of the presence of the cluster even at a temperature equal to or higher than the liquid crystal-isotropic phase transition temperature of a liquid crystal compound, reduction of the Kerr effect is suppressed even if the temperature rises. For example, clusters containing, for example, (a) a liquid crystal compound having an ability of forming an intermolecular hydrogen bond, (b) a liquid crystal compound having a smectic phase, (c) a particulate, (d) or the like, has a large cluster size and thus have a long life even if the temperature rises.