In a liquid crystal display using a liquid crystal exhibiting a smectic phase, a display of good quality is accomplished by alleviating the burn-in phenomenon caused by its layer structure or by an internal electric field induced by spontaneous polarization. To achieve this, the liquid crystal display is equipped with a display data conversion circuit which forcibly sets an arbitrary pixel into a prescribed display state for a prescribed period regardless of the display data to be written to the pixel, thereby correcting the change of its layer structure and preventing the internal electric field due to the spontaneous polarization occurring in the same direction from lasting for too long a period.