Patent ID: 9340009
Filing Date: 2016-05-17
CPC Classification: B41J

Claim Text:
1. A printing apparatus that includes a plurality of nozzle arrays each of which has a plurality of nozzles each discharging ink and being arrayed in a predetermined direction, and that prints on a printing medium by discharging ink from the respective nozzles of the plurality of nozzle arrays while moving the plurality of nozzle arrays and the printing medium relatively in an intersecting direction which intersects the predetermined direction, the apparatus comprising: a control unit configured to control forming, on the printing medium by the plurality of nozzle arrays, of a plurality of patterns corresponding to the plurality of nozzle arrays respectively while moving the plurality of nozzle arrays and the printing medium relatively in the intersecting direction, such that the plurality of patterns formed on the printing medium are arrayed in the predetermined direction; and a determination unit configured to determine a shift amount of a relative printing position between the plurality of nozzle arrays in the intersecting direction, based on a reading result obtained by causing a reading unit to read the plurality of patterns while conveying the printing medium in the intersecting direction, the reading unit including a sensor which has a plurality of reading elements arranged in the predetermined direction such that a reading region that is read by the plurality of reading elements includes a forming region of the plurality of patterns in the predetermined direction, wherein the control unit controls forming of the plurality of patterns such that a first pattern and a second pattern among the plurality of patterns is formed by a first nozzle array among the plurality of nozzle arrays, and the determination unit determines the shift amount using a distance, in an image obtained from the reading result, between a pattern formed by a nozzle array which is different from the first nozzle array and a straight line which passes through the first pattern and the second pattern.