Electrophoretic particles and dielectrophoretic particles are included together in a unit pixel. Each of the electrophoretic particles and the dielectrophoretic particles includes two kinds of particles having different electric properties. The electrophoretic particles include positively charged particles and negatively charged particles. The dielectrophoretic particles include particles having low dielectric constant and particles having high dielectric constant. A first electric field for moving the electrophoretic particles and a second electric field for moving the dielectrophoretic particles are applied to the unit pixel. The second electric field has an asymmetric gradient in the direction where the dielectrophoretic particles move to determine movement directions of the dielectrophoretic particles having different dielectric constants.