Coexistence of ferroelectric and antiferroelectric domains in chiral liquid crystals

Field-induced phase transition in an antiferroelectric liquid crystal (MHPOBC) have been investigated by observing optical transmittance hysteresis loops and microscopic textures. Pseudo-triple hysteresis loops due to coexistence of ferroelectric and antiferroelectric domains have been observed in an antiferroelectric temperature region in homogeneously aligned thin cells. The ratio of the coexisting domain area can be controlled by appropriate driving fields; the controllability leads to an application of antiferroelectric liquid crystal displays with gray scale.