Patent ID: 7387374

Claim:
A droplet ejection head, comprising: a nozzle through which a droplet of liquid is ejected; a pressure chamber which is connected to the nozzle and filled with the liquid to be ejected through the nozzle; a diaphragm which defines a part of the pressure chamber; an electromechanical transducer which is deformed to drive the diaphragm to apply pressure to the liquid inside the pressure chamber so as to cause the droplet to be ejected through the nozzle; and a mechanoelectrical transducer which determines oscillation state in the pressure chamber, wherein the electromechanical transducer and the mechanoelectrical transducer are arranged on the diaphragm to form a layered structure, wherein in the layered structure, the electromechanical transducer is arranged between an electromechanical transducer electrode and a common electrode and the mechanoelectrical transducer is arranged between a mechanoelectrical transducer electrode and the common electrode.