Patent ID: 7607765

Claim:
A liquid-droplet jetting apparatus which jets droplets of liquids onto an object, the apparatus comprising: a cavity unit having a plurality of nozzles, and a plurality of pressure chambers which correspond to the nozzles respectively and which are elongated in a first direction; and a piezoelectric actuator stacked on the cavity unit to cover the pressure chambers, and having a plurality of active portions which are arranged corresponding to the pressure chambers respectively, which change volume of the pressure chambers respectively by being applied with a predetermined drive voltage, and which are elongated in the first direction; wherein the active portions, the nozzles and the pressure chambers are grouped into a first jetting group and a second jetting group; an active portion, among the active portions, included in the first jetting group has a length in the first direction which is greater than that of another active portion included in the second jetting group, and has a length in a second direction, orthogonal to the first direction, which is greater than that of the another active portion included in the second jetting group; and a drive voltage applied to the active portion included in the first jetting group is same as a drive voltage applied to the another active portion included in the second jetting group.