Patent ID: 7484830

Claim:
An ink-jet head, comprising: a nozzle unit including a first nozzle array having a plurality of nozzles of different sizes and at least one second nozzle array having another plurality of nozzles of different sizes, wherein the nozzles of different sizes of the first nozzle array includes a plurality of first nozzles having a first size and a plurality of second nozzles having a second size other than the first size, and the first and second nozzles are alternately arranged, the another plurality of nozzles of different sizes of the second nozzle array includes a plurality of third nozzles having a third size and a plurality of fourth nozzles having a fourth size other than the third size, and the third and fourth nozzles are alternately arranged, adjacent pairs of nozzles of the first nozzle array and the nozzles of the second nozzle array are disposed parallel to a feeding direction of a printing medium, and adjacent pairs of nozzles of the first nozzle array and the second nozzle array in the parallel direction have different sizes from each other.