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

1 . A defective nozzle estimation device that estimates 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 device comprising:

at least one processor; and

at least one memory that stores a command to be executed by the at least one processor,

wherein the at least one processor

acquires imaging data based on a captured image in which the printed matter is imaged by the scanner,

acquires, 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,

acquires 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,

acquires a nozzle mapping table that records 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,

acquires 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,

corrects the nozzle mapping table using the nozzle mapping correction information, and

estimates at least one defective nozzle candidate which is a cause of the image defect of the printed matter using the corrected nozzle mapping table.

2 . The defective nozzle estimation device according to claim 1 ,

wherein the nozzle mapping correction information includes information on an edge position of the print medium in the nozzle direction in the imaging data.

3 . The defective nozzle estimation device according to claim 1 ,

wherein the nozzle mapping correction information includes information on a position of an ink jetted from a specific nozzle of the ink jet head on the print medium in the nozzle direction in the imaging data.

4 . The defective nozzle estimation device according to claim 1 ,

wherein the nozzle mapping correction information includes information on a thickness of the print medium.

5 . The defective nozzle estimation device according to claim 1 ,

wherein the at least one processor

acquires first corrected imaging data based on a first corrected captured image in which a first corrected printed matter, which is printed by being subjected to a first correction process of, in a case in which a plurality of the estimated defective nozzle candidates are present, suppressing an image defect caused by a first defective nozzle candidate that is at least one of the plurality of defective nozzle candidates, is imaged by the scanner, and

determines whether or not the first defective nozzle candidate is a defective nozzle based on the first corrected imaging data.

6 . The defective nozzle estimation device according to claim 5 ,

wherein the at least one processor

acquires second corrected imaging data based on a second corrected captured image in which a second corrected printed matter, which is printed by being subjected to a second correction process of, in a case in which it is determined that the first defective nozzle candidate is not a defective nozzle, suppressing an image defect caused by a second defective nozzle candidate that is at least one of the plurality of defective nozzle candidates and is different from the first defective nozzle candidate, is imaged by the scanner, and

determines whether or not the second defective nozzle candidate is a defective nozzle based on the second corrected imaging data.

7 . The defective nozzle estimation device according to claim 1 ,

wherein, in a case in which a plurality of the estimated defective nozzle candidates are present, the at least one processor

performs a correction process of suppressing an image defect caused by a defective nozzle candidate selected from the plurality of defective nozzle candidates a plurality of times such that each of the plurality of defective nozzle candidates is selected at least once,

acquires a plurality of pieces of corrected imaging data based on a plurality of corrected captured images in which a plurality of corrected printed matters printed using a plurality of pieces of corrected print data obtained by the plurality of times of correction process are imaged by the scanner, and

determines whether or not each of the plurality of defective nozzle candidates is a defective nozzle based on the plurality of pieces of corrected imaging data.

8 . The defective nozzle estimation device according to claim 1 ,

wherein the printing device includes a plurality of the ink jet heads, and

the at least one processor acquires a nozzle mapping table for each of the plurality of ink jet heads.

9 . A printing device comprising:

the defective nozzle estimation device according to claim 1 ;

the ink jet head in which the plurality of nozzles are disposed in the nozzle direction;

the scanner in which the plurality of reading pixels are disposed in the nozzle direction; and

the relative movement mechanism for moving the ink jet head and the scanner, and the print medium relative to each other in the relative movement direction,

wherein the printing device prints the 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 the print source data, and reads the printed matter with the reading pixels of the scanner.

10 . The defective nozzle estimation device according to claim 1 ,

wherein the at least one processor is further configured to calculate a difference between an edge position of the print medium detected from the image data and an edge position of the print medium acquired from the nozzle mapping table to generate the nozzle mapping correction information.

11 . 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.

12 . A method for manufacturing a printed matter, the method comprising:

a printing step of, via a single-pass type printing device which includes an ink jet head in which a plurality of nozzles are disposed in a nozzle direction, 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, printing 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;

an image defect detection step of detecting an image defect of the printed matter by comparing imaging data with reference data;

the defective nozzle estimation method according to claim 11 ; and

a correction process step of performing a correction process of suppressing the image defect caused by the at least one defective nozzle candidate with respect to the print source data.

13 . A non-transitory, computer-readable tangible recording medium on which a program for causing, when read by a computer, the computer to execute the defective nozzle estimation method according to claim 11 is recorded.