Electrostatic actuator and method of driving the same

A camera module for photographing a picture image, comprising:

• an image pick-up element;
• and
• an electrostatic actuator mechanism mounted to the image pick-up element, the electrostatic actuator mechanism including:
• a first stator provided with an electrode group including at least three electrodes successively arranged in a predetermined direction, voltage being applied to the electrodes respectively;
• a second stator arranged to face the first stator and provided with an electrode extending in the predetermined direction;
• a movable member arranged between the first stator and the second stator, and provided with a first electrode section facing the electrode group, a second electrode section facing the electrode extending in the predetermined direction, and an optical element configured to form an optical image on the image pick-up element;
• and
• a switching circuit configured to apply voltage alternately to at least one of the electrodes forming the electrode group and the electrode extending in the predetermined direction, the potential of at least one of the electrodes forming the electrode group being rendered higher than the potential of the first electrode section, or the potential of the electrode extending in the predetermined direction being rendered higher than the potential of the second electrode section, and to switch the order of applying voltage successively to at least one of the electrodes of the electrode group.