Sequentially performed are (1) an entire liquid crystal layer is initialized into a focal conic state, (2) an image is written onto the liquid crystal device by scanning with selecting exposure or non-exposure while applying a voltage that does not exceed a threshold value for a state change from the focal conic state to a homeotropic state during the non-exposure but exceeds the threshold value during the exposure and that causes the focal conic state and the homeotropic state to be bi-stable after the exposure, and (3) the application of the voltage is stopped to change a state of a portion, of which the state has changed to the homeotropic state, to the planer state. In (2), an electric field energy applied to an exposure portion of the liquid crystal layer is controlled to gradually increase from a start to an end of the series of scanning actions.