US Patent 7374276 Inkjet printing head and printer

An inkjet printing head includes: a flow path unit having a plurality of pressure chambers arranged along a plane and connected to nozzles; and an actuator unit fixed on a surface of the flow path unit and changes volume of each of the pressure chambers, the actuator unit including: a plurality of individual electrodes arranged in positions opposite to the pressure chambers respectively; a common electrode disposed to extend over the plurality of pressure chambers and having openings each formed at least at a part of a region opposite to the individual electrodes; and a piezoelectric sheet sandwiched between the common electrode and the individual electrodes.