Printing apparatus and method of correcting step shift thereof

摘要

A printing apparatus performing printing to a print medium includes a printer having at least two line heads with a plurality of recording modules; a scanner configured to scan an image printed with the printer to obtain a scanned image; a correcting-chart printing unit configured to print first and second correcting charts in first and second line head printing areas , respectively; a scanned image collecting unit configured to collect first and second scanned images; a correction-data calculating device configured to calculate correction data by determining a reference head difference from the first scanned image, determining an individual head difference from the second scanned image, summing up the reference head difference and the individual head difference to obtain a total, the reference head difference and the total being regarded as the correction data for the first and second line heads, respectively; and an adjusting device configured to adjust a timing.