Patent ID: 8095031

Claim:
A charging device comprising: a discharge electrode to which a voltage is applied to electrically charge a surface of a photoreceptor; and a grid electrode provided between the discharge electrode and the photoreceptor in order to control a charged potential of the surface of the photoreceptor, wherein the discharge electrode has a vibrating portion that vibrates itself to make the discharge electrode vibrate, wherein the vibrating portion is a piezoelectric bimorph element in which two piezoelectric elements formed of a piezoelectric material in a plate shape are bonded to each other and an electrode layer is provided between the two piezoelectric elements and which vibrates when voltages mutually reverse in phase are applied to the piezoelectric elements, and wherein the discharge electrode is formed in a plate shape with a plurality of acute protruding portions, and in the vibrating portion, a length of each of the piezoelectric elements in a longitudinal direction is set so as to allow vibration to a top end of the acute protruding portions.