Patent ID: 8491094

Claim:
A fluid ejection device that ejects ink from nozzles forming a nozzle line extending in a nozzle line direction perpendicular to a conveyance direction while conveying a recording medium by a paper feed roller in the conveyance direction, forming dots on the recording medium, the fluid ejection device comprising: a first recording head unit having nozzle lines disposed with a gap therebetween in the conveyance direction, and a second recording head unit that has nozzle lines configured in the same way as the nozzle lines of the first recording head unit and is disposed separated from the first recording head unit in the conveyance direction, the first recording head unit and second recording head unit disposed overlapping in a specific range in the nozzle line direction, and the separation distance between a first nozzle line in the first recording head unit and a second nozzle line disposed to the second recording head unit at a position corresponding to the first nozzle line being a distance corresponding to the distance offset the conveyance distance of the recording medium in a half revolution of the paper feed roller from the conveyance distance of the recording medium in an integer number of revolutions of the paper feed roller.