Patent ID: 9452603
Filing Date: 2016-09-27
CPC Classification: B41J

Claim Text:
1. A printing apparatus for performing printing onto a print medium, the printing apparatus comprising: a transporting device; a plurality of printing heads; a photographing unit; a shift detecting chart forming device; and a correcting device, the transporting device transporting a print medium, the printing heads being spaced away from one another in a transportation direction of the print medium and printing an image onto the print medium, the photographing unit photographing the print medium onto which the printing is performed with the printing heads, the shift detecting chart forming device forming a shift detecting chart having a first line segment group and a second line segment group, the first line segment group consisting of first line segments printed onto the print medium at given intervals in an orthogonal direction with respect to the transportation direction with a reference printing head of the printing heads for a reference printing position in the transportation direction, the second line segment group being formed along the first line segment group, and consisting of second line segments printed with a subsequent printing head of the printing heads spaced away from the reference printing head in the transportation direction in such a way that distances to the first line segments become small sequentially and then distances becomes large sequentially in a direction from one of the first line segments to another one of the first line segments, or in such a way that distances to the first line segments become large sequentially and then distances becomes small sequentially in a direction from one of the first line segments to another one of the first line segments, and the correcting device correcting a printing timing with the subsequent printing head relative to the reference printing head in accordance with a density variation of the shift detecting chart photographed with the photographing unit.