Piezoelectric actuator, liquid-drop ejecting head, and liquid-drop ejecting apparatus

A liquid drop ejecting head, comprising:

• a plurality of piezoelectric actuators including a deformable diaphragm of a substantially rectangular shape, a first electrode formed on a face of the diaphragm, a piezoelectric layer formed on a first face of the first electrode opposite a second face of the first electrode contacting the diaphragm, and a second electrode formed on a first face of the piezoelectric layer opposite a second face of the piezoelectric layer contacting the first electrode and divided into three portions in a cross section in a short-side direction of the diaphragm,
• a first common potential supplied to the first electrode of the plurality of piezoelectric actuators,
• a control potential supplied to a portion located between the other two portions of the three portions of the second electrode,
• a second common potential supplied to the other two portions.

A liquid drop ejecting apparatus comprising a liquid drop ejecting head with a plurality of piezoelectric actuators,

• the plurality of piezoelectric actuators including a deformable diaphragm of a substantially rectangular shape, a first electrode formed on a face of the diaphragm, a piezoelectric layer formed on a first face of the first electrode opposite a first face of the first electrode contacting the diaphragm, and a second electrode formed on a first face of the piezoelectric layer opposite a second face of the piezoelectric layer contacting the first electrode and divided into three portions in a cross section in a short-side direction of the diaphragm,
• a first common potential supplied to the first electrode of the plurality of piezoelectric actuators,
• a control potential supplied to a portion located between the other two portions of the three portions of the second electrode,
• a second common potential supplied to the other two portions.