When a voltage is applied between outside electrodes and a common electrode that constitute driving parts of a driving unit provided between a holder holding a lens and a lens barrel, as shown in FIG. 9, respective dielectric elastomers provided in the driving parts are slightly deformed in a direction that is crushed in an X1 X2 direction. Thus, the entire lens can be slightly moved in the direction of an arrow (X2-direction). This enables an optical axis O'--O' of the lens to coincide with or get closer to a reference optical axis.