Patent ID: 7152963

Claim:
A liquid jet head comprising: a passage-forming substrate including at least two rows of pressure generating chambers, each communicating with a nozzle orifice; piezoelectric elements for causing pressure change in the pressure generating chambers, the piezoelectric elements being provided on one side of the passage-forming substrate with a vibration plate interposed therebetween; a joint plate joined to the piezoelectric element side of the passage-forming substrate; and driving ICs for driving the piezoelectric elements, the driving ICs being provided in regions on the joint plate, the regions facing the respective rows of the pressure generating chambers, wherein in the joint plate, at least one penetrated hole, in which lead electrodes led from the piezoelectric elements are exposed, is provided for each row of the pressure generating chambers in a region corresponding to a region between the rows of the pressure generating chambers, and a beam portion is formed between the adjacent penetrated holes.