Defective nozzle estimation device, defective nozzle estimation method, defective nozzle estimation program, printing device, and method for manufacturing printed matter

A defective nozzle estimation method of estimating a defective nozzle of an ink jet head, in which a plurality of nozzles are disposed in a nozzle direction, of a single-pass type printing device which includes the ink jet head, a scanner in which a plurality of reading pixels are disposed in the nozzle direction, and a relative movement mechanism for moving the ink jet head and the scanner, and a print medium relative to each other in a relative movement direction intersecting the nozzle direction, and which prints a printed matter on the print medium relatively moved in the relative movement direction by jetting an ink from the nozzle of the ink jet head onto the print medium on the basis of print source data and reads the printed matter with the reading pixels of the scanner, the defective nozzle estimation method comprising:

• an imaging data acquisition step of acquiring imaging data based on a captured image in which the printed matter is imaged by the scanner;
• a reference data acquisition step of acquiring, as reference data, the print source data or reference imaging data based on a reference captured image in which a reference printed matter is imaged by the scanner;
• an image defect position acquisition step of acquiring a position in the nozzle direction of an image defect of the printed matter caused by the defective nozzle in the imaging data by comparing the imaging data with the reference data;
• a nozzle mapping information acquisition step of acquiring a nozzle mapping table that records indicating a correspondence relationship between positions of the plurality of nozzles and pixel positions of the imaging data in the nozzle direction, wherein the nozzle mapping table is stored in advance in the at least one memory;
• a nozzle mapping correction information acquisition step of acquiring nozzle mapping correction information for correcting a positional relationship between at least two of the print medium, the ink jet head, and the scanner in the nozzle direction;
• a nozzle mapping information correction step of correcting the nozzle mapping table using the nozzle mapping correction information;
• and
• a defective nozzle candidate estimation step of estimating at least one defective nozzle candidate which is a cause of the image defect of the printed matter using the corrected nozzle mapping table.