Patent ID: 8083319

Claim:
An inkjet printer comprising: a recording head formed with a plurality of ejection holes including a plurality of first ejection holes and a plurality of second ejection holes arranged in a first direction to eject ink droplets onto a recording medium having a plurality of invisible columns extending in the first direction and a plurality of invisible rows extending in a second direction orthogonal to the first direction, each of the plurality of invisible columns being equally spaced in the second direction, each of the plurality of invisible rows being equally spaced in the first direction, the plurality of invisible columns having a plurality of first invisible columns and a plurality of second invisible columns alternately arranged in the second direction, ink droplets being ejectable from the plurality of ejection holes onto intersecting points of the plurality of invisible columns with the plurality of invisible rows; a scanning unit configured to perform a first scan to move the recording head in the second direction, and configured to perform, after the first scan, a second scan to move the recording head in the second direction, the plurality of ejection holes moving, in the second scan, along the plurality of invisible rows different from the plurality of invisible rows along which the plurality of ejection holes moves respectively in the first scan; and a controller configured to prevent the recording head in the first scan from ejecting ink droplets from the plurality of first ejection holes onto the plurality of first invisible columns and from the plurality of second ejection holes onto the plurality of second invisible columns, and configured to prevent the recording head in the second scan from ejecting ink droplets from the plurality of first ejection holes onto the plurality of second invisible columns and from the plurality of second ejection holes at the plurality of first invisible columns.