Patent ID: 8366247

Claim:
A liquid ejection head comprising: an orifice plate including a plurality of ejection ports for ejecting liquid to a printing medium, a substrate including a plurality of heat generating elements for generating energy used to eject liquid, a plurality of liquid supply ports, which are through holes, for supplying liquid to the heat generating elements, and a beam formed between the liquid supply ports, and a plurality of nozzle groups, each of which is formed as one unit by combining a plurality of liquid chambers that communicate with the liquid supply ports and that are formed between the orifice plate and the substrate, and pressure chambers that are formed in the liquid chambers, each of which has a communication port communicating with a liquid supply port, each nozzle group including heat generating elements, liquid supply ports, and ejection ports, wherein a nozzle group includes the pressure chambers arranged therein in a row, wherein the plurality of nozzle groups are arranged in the substrate along the direction along which the pressure chambers are arranged to thereby form a plurality of nozzle group arrays, and wherein in the nozzle group arrays adjacent to one another, the plurality of nozzle groups forming the nozzle group arrays are formed to be offset from one another in the direction along which the pressure chambers are arranged.