Liquid discharge apparatus, image processing method, and image processing program

Abstract

A liquid ejecting apparatus, an image processing method, and an image processing program are disclosed. The liquid ejecting apparatus includes a printing section that prints a check image, a reading section that reads the check image printed by the printing section, and an analysis section that performs analysis based on a reading result read by the reading section, the check image having a first position detection mark printed in a first color, a second position detection mark printed in the first color, and a check pattern of a plurality of colors including a second color check pattern printed in a second color different from the first color, the printing section printing the second color check pattern at a position adjacent to the first position detection mark, and the analysis section determining a first position of the first position detection mark in a first area and determining a second position of the second position detection mark in a second area narrower than the first area.

Description

Technical Field

[0001] This disclosure relates to a liquid ejection device, an image processing method, and an image processing program. Background Technology

[0002] There are known image processing methods that use recorded test patterns to determine recording defects. Patent Document 1 describes an inkjet recording apparatus that prints a non-spray detection pattern including detection marks. The detection marks are marks used for position detection. The inkjet recording apparatus reads the non-spray detection pattern and performs non-spray detection processing based on the reading result. The inkjet recording apparatus determines that a defective nozzle has been ejected by performing non-spray detection processing.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2015-3515

[0004] The detection accuracy of the detection markers can be reduced due to the positional relationship between the markers and the images adjacent to them, or due to the influence of the colors of the images adjacent to the markers. Summary of the Invention

[0005] The liquid ejection device disclosed herein includes: a printing unit for printing an inspection image; a reading unit for reading the inspection image printed by the printing unit; and an analysis unit for analyzing the reading result read by the reading unit. The inspection image has a first position detection mark printed with a first color, a second position detection mark printed with the first color, and an inspection pattern comprising multiple colors including a second color inspection pattern printed with a second color different from the first color. The printing unit prints the second color inspection pattern at a position adjacent to the first position detection mark. The analysis unit determines a first position of the first position detection mark in a first region and a second position of the second position detection mark in a second region smaller than the first region.

[0006] According to the image processing method of this disclosure, an inspection image is printed having a first position detection mark formed with a first color, a second position detection mark formed with the first color, and an inspection pattern containing multiple colors including a second color inspection pattern formed with a second color different from the first color, in such a way that a second color inspection pattern is arranged at a position adjacent to a first position detection mark. The inspection image is read and a reading result is obtained. A first position of the first position detection mark is determined in a first region, and a second position of the second position detection mark is determined in a second region that is smaller than the first region.

[0007] According to the image processing program executed by the processor of the liquid ejection device for printing inspection images disclosed herein, the following processing is performed: printing an inspection image having the first position detection mark formed with the first color, the second position detection mark formed with the first color, and an inspection pattern comprising multiple colors including the second color inspection pattern formed with a second color different from the first color, in such a manner that the second color inspection pattern is arranged at a position adjacent to the first position detection mark; reading the inspection image and obtaining a reading result; determining a first position of the first position detection mark in a first region; and determining a second position of the second position detection mark in a second region smaller than the first region. Attached Figure Description

[0008] Figure 1 It is a diagram showing the general structure of a printing apparatus.

[0009] Figure 2 It is a diagram showing the general structure of a printing apparatus.

[0010] Figure 3 It is a diagram showing the relationship between the printing medium and the print head.

[0011] Figure 4 It is a diagram showing the functional block diagram of a printing apparatus.

[0012] Figure 5 It is a diagram that represents an overview of the test pattern image.

[0013] Figure 6 It is an enlarged view of the test pattern image containing the first mark.

[0014] Figure 7 This is a graph showing the concentration distribution in the first measurement area.

[0015] Figure 8 It is an enlarged view of the test pattern image containing the second mark.

[0016] Figure 9 This is a graph showing the concentration distribution in the second measurement area.

[0017] Figure 10 This is a flowchart illustrating the image processing performed in a printing apparatus.

[0018] Figure 11 It is an enlarged view of the test pattern image containing the third mark.

[0019] Explanation of reference numerals in the attached figures

[0020] 10…Printing apparatus; 11…Feed shaft; 13…Feed roller pair; 13A…First feed roller; 13B…Second feed roller; 15…Reading sensor; 16…Printing mechanism; 17…Carriage; 18…Print head; 19…Carriage support shaft; 20…Ink nozzle; 20C…Cyan ink nozzle array; 20LC…Bright cyan ink nozzle array; 20M…Magenta ink nozzle array; 20LM…Bright magenta ink nozzle array; 20Y…Yellow ink nozzle array; 20K…Black ink nozzle array; 25…Conveyor roller pair; 25A…First conveyor roller; 25B…Second conveyor roller; 27…Take-up shaft; 30 …Control unit; 31…Printing control unit; 33…Reading control unit; 35…Data processing unit; 37…Storage unit; 40…Display unit; 50…Communication interface; 60…Conveying mechanism; 70…Printing drive mechanism; 80…Print head drive mechanism; 90…Detection mechanism; 95…First side plate; 97…Second side plate; 100…Test pattern image; 110…Mark image; 110A…First mark; 110B…Second mark; 110C…Third mark; 110D…Fourth mark; 110E…Fifth mark; 110F…Sixth mark; 110G…Seventh mark; 110H…Eighth mark; 120…Pattern image; 120A…First pattern; 120B…Second pattern; 120C…Third pattern; 120D…Fourth pattern; 120E…Fifth pattern; 120F…Sixth pattern; 122…Line image; 130…Measurement area; 130A…First measurement area; 130AL…Length of first measurement area; 130AW…Width of first measurement area; 130B…Second measurement area; 130BL…Length of second measurement area; 130BW…Width of second measurement area; 130C…Third measurement area; 130CL… Length of the third measurement area; 130CW… Width of the third measurement area; 160A… First mark concentration distribution; 160B… Second mark concentration distribution; 170A… First pattern concentration distribution; 170F… Sixth pattern concentration distribution; 170AK… Imaginary first pattern concentration distribution; M… Printing medium; MD… Direction of movement; P1… First mark center of gravity position; P1A… Imaginary center of gravity position; P2… Second mark center of gravity position; PD… Nozzle arrangement direction; R1… Medium roll; R2… Take-up roll; TD… Transport direction; VL1… First imaginary line; VL2… Second imaginary line. Detailed Implementation

[0021] Figure 1 and Figure 2 This shows the general structure of the printing apparatus 10. Figure 1 This is a diagram of the printing apparatus 10 viewed from the +X direction. Figure 2This is a view of the printing apparatus 10 from the +Z direction. The printing apparatus 10 performs printing on a printing medium M fed from a media roll R1. The printing apparatus 10 is an inkjet type that ejects ink into the printing medium M. The printing apparatus 10 corresponds to an example of a liquid ejection apparatus. The printing medium M corresponds to an example of a medium.

[0022] include Figure 1 Part of the accompanying drawings illustrates the XYZ coordinate system. The X, Y, and Z axes are orthogonal to each other. The X-axis is parallel to the mounting surface of the printing apparatus 10. The X-axis is an axis parallel to the rotation axis of the media roll R1 loaded in the printing apparatus 10. The rotation axis of the media roll R1 refers to the imaginary center axis of rotation when the media roll R1 rotates. From Figure 1 The direction of the depth side towards the near-anterior side is the +X direction. From Figure 1 The direction from the front side towards the depth side is the -X direction. The Y-axis is parallel to the mounting surface of the printing device 10. The Y-axis is an axis orthogonal to the rotation axis of the media roll R1. Figure 1 The direction shown from the right side of the printing device 10 to the left is the +Y direction. Figure 1 The direction from left to right of the printing apparatus 10 is the -Y direction. The Z-axis is the axis perpendicular to the mounting surface of the printing apparatus 10. The direction upward from the mounting surface is the +Z direction. The direction upward from above is the -Z direction.

[0023] Figure 1 and Figure 2 The various portions arranged along the printing medium M are shown. Figure 1 and Figure 2 The printing apparatus 10 shown includes a feed shaft 11, a feed roller pair 13, a reading sensor 15, a printing mechanism 16, a transport roller pair 25, and a take-up shaft 27.

[0024] The feed shaft 11 supports a media roll R1 that winds the printing medium M into a roll. The feed shaft 11 is supported to be rotatable. The feed shaft 11 can also be connected to a rotary drive mechanism (not shown). The rotary drive mechanism rotates the feed shaft 11. The rotating feed shaft 11 feeds the printing medium M wound into the media roll R1.

[0025] The feed roller pair 13 feeds the printing medium M toward the printing mechanism 16. Hereinafter, the direction in which the printing medium M is conveyed in the position opposite to the printing mechanism 16 is denoted as the conveying direction TD. The feed roller pair 13 holds the printing medium M. The feed roller pair 13 has a first feed roller 13A and a second feed roller 13B. The first feed roller 13A is positioned in the +Z direction of the second feed roller 13B. The first feed roller 13A is in contact with the surface of the printing medium M in the +Z direction. The second feed roller 13B is in contact with the surface of the printing medium M in the -Z direction. The printing medium M is held by the first feed roller 13A and the second feed roller 13B. One of the first feed roller 13A and the second feed roller 13B is connected to a drive mechanism (not shown). One of the first feed roller 13A and the second feed roller 13B rotates by the driving force of the drive mechanism. The other of the first feed roller 13A and the second feed roller 13B rotates passively. The feed roller pair 13, driven by the drive mechanism, feeds the printing medium M toward the printing mechanism 16. Furthermore, the feed roller pair 13 conveys the printing medium M in the opposite direction to the conveying direction TD.

[0026] The reading sensor 15 reads the surface of the printed medium M. The reading sensor 15 is composed of image sensors such as CIS (Contact Image Sensor) and CCD (Charge Coupled Device). Figure 1 The reading sensor 15 shown reads the overall width of the printed medium M, parallel to the X-axis. Figure 1 and Figure 2 In the printing apparatus 10 shown, the reading sensor 15 reads the printing medium M located between the feed roller pair 13 and the printing mechanism 16. Figure 1 and Figure 2 The printing apparatus 10 shown conveys the printing medium M in the direction opposite to the transport direction TD. A reading sensor 15 reads the printing medium M conveyed in the direction opposite to the transport direction TD. The reading sensor 15 also reads images such as a test pattern image 100 printed on the printing medium M by the printing mechanism 16. The test pattern image 100 will be described later. The position of the reading sensor 15 is not limited to the position between the feed roller pair 13 and the printing mechanism 16. The reading sensor 15 can also be configured between the printing mechanism 16 and the transport roller pair 25 on the transport path of the printing medium M. The reading sensor 15 corresponds to one example of a reading unit.

[0027] The readout sensor 15 has a light-emitting portion and a light-receiving portion (not shown). The light-emitting portion emits light by sequentially switching between red, green, and blue light. The light-receiving portion receives reflected light from the printing medium M when the light-emitting portion emits various colors of light. The light-receiving data when the light-emitting portion emits red light is represented as the red channel. The red channel is image data from which the red component is extracted. The light-receiving data when the light-emitting portion emits green light is represented as the green channel. The green channel is image data from which the green component is extracted. The light-receiving data when the light-emitting portion emits blue light is represented as the blue channel. The blue channel is image data from which the blue component is extracted. The readout data generated by the readout sensor 15 is image data containing the red, green, and blue channels. Each of the red, green, and blue channels corresponds to an example of the first and second channels.

[0028] The printing mechanism 16 prints an image on the printing medium M. The printing mechanism 16 ejects ink from the printing medium M to form an image. The printing mechanism 16, as... Figure 1 The device shown includes a carriage 17 and a print head 18. The print head 18 has multiple ink nozzles 20. The printing mechanism 16 consists of... Figure 2 The carriage support shaft 19 is shown. Figure 1 and Figure 2 The printing mechanism 16 shown moves the carriage 17, but is not limited to this. The printing mechanism 16 can also be a line head type that fixes the print head 18 relative to the printing medium M during printing. The printing mechanism 16 corresponds to one example of a printing section. Ink corresponds to one example of a liquid.

[0029] The carriage 17 supports the printing head 18. The carriage 17 moves along... Figure 2 The carriage support shaft 19 shown moves in the moving direction MD or in the opposite direction to the moving direction MD. The printing mechanism 16 moves relative to the printing medium M by moving the carriage 17. Figure 2 The carriage support shaft 19 shown is parallel to, or approximately parallel to, the X-axis. The carriage 17 moves relative to the printing medium M along the +X and -X directions. By moving the carriage 17, the printing mechanism 16 causes the ink nozzles 20 to scan relative to the printing medium M. Figure 2 As shown, the +X direction is the movement direction MD, corresponding to one example of the first direction. The movement direction MD can also be the -X direction. The carriage 17 moves by the driving force of a carriage drive mechanism (not shown). The carriage 17 corresponds to one example of an ejection section drive mechanism. Figure 1 and Figure 2 In the printing apparatus 10 shown, the printing mechanism 16 moves relative to the printing medium M, but is not limited thereto. The printing mechanism 16 moves relative to the printing medium M.

[0030] The print head 18 is supported by a carriage 17. The print head 18 has multiple ink nozzles 20 on its printing surface opposite the printing medium M. The ink nozzles 20 are capable of ejecting ink onto the printing medium M. Each ink nozzle 20 corresponds to an example of a nozzle. The structure of the ink nozzles 20 will be described later. The print head 18 is supplied with ink of various colors from an ink canister or cartridge not shown in the figure.

[0031] The carriage support shaft 19 supports the carriage 17 so that it can move. The carriage support shaft 19 is as follows... Figure 2 The carriage is supported by a first side plate 95 and a second side plate 97. The first side plate 95 is positioned in the -X direction of the conveyed printing medium M. The second side plate 97 is positioned in the +X direction of the conveyed printing medium M. The carriage support shaft 19 is supported along an axis intersecting the Y-axis. Figure 2 The carriage support shaft 19 shown is supported parallel or approximately parallel to the X-axis. The first side plate 95 and the second side plate 97 can also support the delivery roller pair 13, the reading sensor 15, and the conveyor roller pair 25.

[0032] The conveyor roller pair 25 conveys the printing medium M printed by the printing mechanism 16. The conveyor roller pair 25 holds the printing medium M. The conveyor roller pair 25 has a first conveyor roller 25A and a second conveyor roller 25B. The first conveyor roller 25A is positioned in the +Z direction relative to the second conveyor roller 25B. The first conveyor roller 25A is in contact with the surface of the printing medium M in the +Z direction. The second conveyor roller 25B is in contact with the surface of the printing medium M in the -Z direction. The printing medium M is held by the first conveyor roller 25A and the second conveyor roller 25B. One of the first conveyor roller 25A and the second conveyor roller 25B can also be connected to a drive mechanism (not shown). When connected to the drive mechanism, one of the first conveyor roller 25A and the second conveyor roller 25B rotates by the driving force of the drive mechanism. The other of the first conveyor roller 25A and the second conveyor roller 25B rotates passively. The conveyor roller pair 25 guides the printing medium M toward the take-up roll R2. Furthermore, the conveyor roller pair 25 can also convey the printing medium M in the direction opposite to the conveying direction TD.

[0033] The take-up spool 27 winds the printed medium M, printed by the printing mechanism 16, into a take-up roll R2. The take-up spool 27 supports the take-up roll R2. The take-up spool 27 is rotatably supported. The take-up spool 27 can also be connected to a rotary drive mechanism (not shown). The rotary drive mechanism rotates the take-up spool 27. The rotating take-up spool 27 winds the printed medium M into the take-up roll R2. The take-up spool 27 can also wind the printed medium M via a core (not shown).

[0034] Figure 1 and Figure 2The printing apparatus 10 shown uses a printing medium M wound into a media roll R1, but is not limited to this. The printing apparatus 10 may also use cut paper cut to a specified size. When the printing apparatus 10 uses cut paper, the feed shaft 11 and the take-up shaft 27 are replaced with a paper feed tray and a paper discharge tray, respectively.

[0035] Figure 3 This indicates the relationship between the printing medium M and the print head 18. Figure 3 The carriage 17 and carriage support shaft 19 are omitted. Figure 3 The reading sensor 15 is shown. Figure 3 The print head 18 shown moves along the moving direction MD to print an image on the printing medium M. Figure 3 The indicated direction of movement MD corresponds to the +X direction. Multiple ink nozzles 20 are arranged on the printing surface of the print head 18 opposite the printing medium M. The multiple ink nozzles 20 form multiple nozzle rows. Figure 3 The ink nozzles 20 shown form a magenta ink nozzle array 20M, a bright magenta ink nozzle array 20LM, a cyan ink nozzle array 20C, a bright cyan ink nozzle array 20LC, a yellow ink nozzle array 20Y, and a black ink nozzle array 20K.

[0036] The magenta ink nozzle array 20M has multiple ink nozzles 20 arranged along the nozzle arrangement direction PD. Figure 3 The nozzle arrangement direction PD shown is the same as the transport direction TD, but is not limited to it. The nozzle arrangement direction PD is a different direction from the movement direction MD. The ink nozzles 20 contained in the magenta ink nozzle array 20M are capable of ejecting magenta ink. Magenta ink refers to ink of the color magenta. Magenta ink is supplied to the print head 18 by an ink can or cartridge not shown. The magenta ink supplied to the print head 18 is ejected by the ink nozzles 20 contained in the magenta ink nozzle array 20M.

[0037] The bright magenta ink nozzle array 20LM has multiple ink nozzles 20 arranged along the nozzle arrangement direction PD. The ink nozzles 20 in the bright magenta ink nozzle array 20LM are capable of ejecting bright magenta ink. Bright magenta ink refers to ink of the bright magenta color. Bright magenta ink is supplied to the print head 18 from an ink can or cartridge not shown. The bright magenta ink supplied to the print head 18 is ejected from the ink nozzles 20 in the bright magenta ink nozzle array 20LM.

[0038] Cyan ink nozzle array 20C has along Figure 3 The nozzle arrangement shown is a plurality of ink nozzles 20 arranged in the direction PD. The ink nozzles 20 contained in the cyan ink nozzle array 20C are capable of ejecting cyan ink. Cyan ink refers to ink of the color cyan. Cyan ink is supplied to the print head 18 by an ink can or cartridge not shown. The cyan ink supplied to the print head 18 is ejected by the ink nozzles 20 contained in the cyan ink nozzle array 20C.

[0039] The cyan ink nozzle array 20LC has multiple ink nozzles 20 arranged along the nozzle arrangement direction PD. The ink nozzles 20 in the cyan ink nozzle array 20LC are capable of ejecting cyan ink. Cyan ink refers to ink of a bright cyan color. Cyan ink, as shown in the diagram, is supplied to the print head 18 from an ink can or cartridge. The cyan ink supplied to the print head 18 is ejected from the ink nozzles 20 in the cyan ink nozzle array 20LC.

[0040] The yellow ink nozzle array 20Y has multiple ink nozzles 20 arranged along the nozzle arrangement direction PD. The ink nozzles 20 in the yellow ink nozzle array 20Y are capable of ejecting yellow ink. Yellow ink refers to ink that is yellow in color. Yellow ink is supplied to the print head 18 by an ink can or cartridge not shown. The yellow ink supplied to the print head 18 is ejected by the ink nozzles 20 in the yellow ink nozzle array 20Y.

[0041] The black ink nozzle array 20K has multiple ink nozzles 20 arranged along the nozzle arrangement direction PD. The ink nozzles 20 in the black ink nozzle array 20K are capable of ejecting black ink. Black ink refers to black ink. Black ink is supplied to the print head 18 by an ink can or cartridge not shown. The black ink supplied to the print head 18 is ejected by the ink nozzles 20 in the black ink nozzle array 20K.

[0042] Figure 3 The printhead 18 shown can eject six types of ink, but is not limited to this. The printhead 18 can also be configured to eject five or fewer types of ink, or it can be configured to eject seven or more types of ink. The printhead 18 only needs to be able to eject two or more types of ink. Figure 3 The number of ink nozzles 20 in each nozzle row shown is 14, but not limited to this. The number of ink nozzles 20 in each nozzle row can be less than 14 or more than 14. The number of ink nozzles 20 in each nozzle row can be appropriately set. Figure 3 The printhead 18 shown is configured relative to the movement direction MD in the following order: magenta ink nozzle row 20M, bright magenta ink nozzle row 20LM, cyan ink nozzle row 20C, bright cyan ink nozzle row 20LC, yellow ink nozzle row 20Y, and black ink nozzle row 20K, but is not limited to this. The configuration order of each nozzle row can be changed appropriately.

[0043] Magenta, bright magenta, cyan, bright cyan, yellow, and black are examples of ink colors, but are not limited to these. Any two of magenta, bright magenta, cyan, bright cyan, yellow, and black correspond to an example of the first and second colors.

[0044] Figure 4This diagram illustrates the block structure of the printing apparatus 10. The printing apparatus 10 includes a control unit 30, a display unit 40, a communication interface 50, a conveying mechanism 60, a printing drive mechanism 70, a print head drive mechanism 80, and a detection mechanism 90. Figure 4 The interface is represented as I / F.

[0045] The control unit 30 is a controller that controls the various parts of the printing apparatus 10. The control unit 30 includes a control processor such as a CPU (Central Processing Unit), RAM (Random Access Memory), and ROM (Read Only Memory). The control unit 30 operates as a functional part by executing programs in the control processor. The RAM and ROM function as working areas. The control unit 30 corresponds to an example of a processor.

[0046] The control unit 30 includes a storage unit 37. The storage unit 37 stores various programs and data, such as printing control programs, that are used in the control unit 30. The storage unit 37 stores test pattern data, calibration data, etc., as described later. RAM and ROM can also function as the storage unit 37, and it can also include magnetic storage devices such as HDDs (Hard Disk Drives) and semiconductor memories.

[0047] The control unit 30 functions as the printing control unit 31, the reading control unit 33, and the data processing unit 35 by executing the printing control program. The printing control unit 31, the reading control unit 33, and the data processing unit 35 are functional units.

[0048] The printing control unit 31 controls the printing drive mechanism 70 and the print head drive mechanism 80. By controlling the printing drive mechanism 70 and the print head drive mechanism 80, the printing control unit 31 can control the printing mechanism 16. The printing control unit 31 prints an image on the printing medium M using the printing mechanism 16. The printing control unit 31 acquires printing data. The printing data is stored in the storage unit 37. Alternatively, printing data can be acquired from an external device via the communication interface 50. The printing control unit 31 controls the printing drive mechanism 70 and the print head drive mechanism 80 based on the printing data, thereby printing an image on the printing medium M.

[0049] The reading control unit 33 controls various sensors, including the reading sensor 15, included in the detection mechanism 90. The reading control unit 33 reads images printed on the printing medium M by controlling the reading sensor 15. The read images are, for example, test pattern images 100. The reading control unit 33 receives read data from the reading sensor 15. The received read data is then sent to the data processing unit 35.

[0050] The data processing unit 35 performs various data analyses based on the data generated in the testing mechanism 90. The data processing unit 35 receives read data from the read sensor 15 and analyzes the read data. When the received read data is read data obtained from reading the test pattern image 100, the data processing unit 35 analyzes the read data to determine the image position within the test pattern image 100, generate correction data, and determine defective nozzles, etc. The data processing unit 35 corresponds to one example of an analysis unit. The read data corresponds to one example of a read result.

[0051] The display unit 40 performs various displays under the control of the control unit 30. The display unit 40 includes a monitor. The monitor is composed of a liquid crystal display (LCD) or an organic EL (electroluminescence) display, etc. The monitor may also have touch input functionality. The display unit 40 displays setting screens for various printing conditions and other settings, as well as printing instruction screens.

[0052] Communication interface 50 establishes a communication connection with an external device (not shown). Communication interface 50 connects to the external device via wired or wireless means according to a defined communication protocol. Communication interface 50 receives printing data, printing settings, programs, etc., from the external device. Communication interface 50 also transmits printing results and maintenance data from the printing apparatus 10 to the external device.

[0053] The conveying mechanism 60 conveys the printing medium M in the conveying direction TD or in the opposite direction to TD. The conveying mechanism 60 includes a feed shaft 11, a feed roller pair 13, a conveying roller pair 25, and a take-up shaft 27. The conveying mechanism 60 conveys the printing medium M under the control of the printing control unit 31 or the reading control unit 33. When the printing apparatus 10 is printing on the printing medium M, the conveying mechanism 60 conveys the printing medium M in the conveying direction TD under the control of the printing control unit 31. When the reading sensor 15 reads the test pattern image 100 printed on the printing medium M, the conveying mechanism 60 conveys the printing medium M in the opposite direction to TD under the control of the reading control unit 33.

[0054] The printing drive mechanism 70 drives the printing mechanism 16. The printing drive mechanism 70 includes a carriage 17, a carriage drive mechanism, and a carriage support shaft 19. The printing drive mechanism 70 moves the carriage 17 along the movement direction MD. As the carriage 17 moves along the movement direction MD, the plurality of ink nozzles 20 contained in the print head 18 scan the printing medium M. The printing mechanism 16 scans the plurality of ink nozzles 20 via the carriage 17. The scanned ink nozzles 20 eject ink, thereby forming an image on the printing medium M. When the printing mechanism 16 is a line head type, the printing drive mechanism 70 can also function as a correction mechanism to correct the serpentine movement of the printing medium M.

[0055] The printhead drive mechanism 80 controls the ink ejection from the ink nozzles 20 according to the control of the printing control unit 31. The printhead drive mechanism 80 includes drive elements such as piezoelectric elements arranged in the printhead 18. Each ink nozzle 20 ejects ink by being driven by the printhead drive mechanism 80. The printhead drive mechanism 80 performs printing on the printing medium M by driving multiple ink nozzles 20. The printhead drive mechanism 80 prints the test pattern image 100 on the printing medium M by driving multiple ink nozzles 20.

[0056] The detection mechanism 90 detects various operations of the printing apparatus 10, the presence or absence of the printing medium M, etc. The detection mechanism 90 includes a reading sensor 15, a paper detection sensor (not shown), an ink level sensor, etc. The detection mechanism 90 is driven according to the control unit 30. The reading sensor 15 reads the image printed on the printing medium M according to the instructions of the reading control unit 33 within the control unit 30. The reading action of the reading sensor 15 corresponds to the detection action. The detection mechanism 90 sends the detection data generated by the various sensors to the control unit 30. The reading sensor 15 sends the read data to the control unit 30.

[0057] Figure 5 This indicates an overview of the test pattern image 100 printed on the printing medium M. Figure 5 The test pattern image 100 shown was printed when checking for poor ink ejection from the ink nozzle 20. Figure 5 The test pattern image 100 shown corresponds to an example of the inspection image. Figure 5 The test pattern image 100 is shown simplified by omitting a portion of the image.

[0058] The test pattern image 100 is printed based on test pattern data stored in the storage unit 37. The test pattern data is printing data pre-stored in the storage unit 37. The test pattern data includes information such as the shape, size, and relative position of each image contained in the printed test pattern image 100. The test pattern data may also include color data for each image. The printing apparatus 10 reads the test pattern data stored in the storage unit 37. Based on the read test pattern data, the printing apparatus 10 prints the test pattern image 100 onto the printing medium M.

[0059] Test pattern image 100 includes marker image 110 and pattern image 120. Figure 5The marked image 110 shown is composed of multiple circular images of a specified size. The marked image 110 is used by the printing apparatus 10 to determine the printing position on the printing medium M. The pattern image 120 is a pattern composed of multiple line images 122. The multiple line images 122 are arranged in a stepped pattern. Each of the multiple line images 122 is printed from an ink nozzle 20. The pattern image 120 is used by the printing apparatus 10 to determine if there is a problem with the ink nozzle 20 ejecting ink. The pattern image 120 corresponds to an example of an inspection pattern.

[0060] Figure 5 The marked image 110 shown is composed of a first mark 110A, a second mark 110B, a third mark 110C, a fourth mark 110D, a fifth mark 110E, a sixth mark 110F, a seventh mark 110G, and an eighth mark 110H. The first mark 110A, the third mark 110C, the fifth mark 110E, and the seventh mark 110G are arranged in the -X direction of the pattern image 120 along a direction parallel to the Y-axis. The second mark 110B, the fourth mark 110D, the sixth mark 110F, and the eighth mark 110H are arranged in the +X direction of the pattern image 120 along a direction parallel to the Y-axis. Figure 5 The multiple circular images of the marker image 110 shown are printed along the X-axis at positions sandwiching the pattern image 120. The position and number of each circular image can be changed appropriately.

[0061] Figure 5 The marked image 110 shown consists of eight marks that form a circular image, but is not limited to this. The number of marks constituting the marked image 110 can be different from eight, as long as there are two or more marks. Figure 5 The marks shown are all of the same circular shape, but are not limited to this. The shapes of the multiple marks can be the same or different, as long as the printing positions of the images printed on the printing medium M can be determined. It is preferred that the multiple marks have the same shape. When the multiple marks have the same shape, the printing positions of the images printed on the printing medium M are easily determined.

[0062] Figure 5 The marked image 110 shown is printed using black ink nozzle column 20K. Figure 5 The color of the marker image 110 shown is black. However, the color of the marker image 110 is not limited to black. The color of the marker image 110 can be set appropriately.

[0063] Figure 5The pattern image 120 shown includes a first pattern 120A, a second pattern 120B, a third pattern 120C, a fourth pattern 120D, a fifth pattern 120E, and a sixth pattern 120F. The first pattern 120A, second pattern 120B, third pattern 120C, fourth pattern 120D, fifth pattern 120E, and sixth pattern 120F are printed sequentially along the +X direction. The first pattern 120A is printed at a position in the +X direction adjacent to the first mark 110A, third mark 110C, fifth mark 110E, and seventh mark 110G. In the test pattern image 100, the first pattern 120A is positioned at a position in the +X direction adjacent to the first mark 110A, third mark 110C, fifth mark 110E, and seventh mark 110G. The sixth pattern 120F is printed at a position in the -X direction adjacent to the second mark 110B, fourth mark 110D, sixth mark 110F, and eighth mark 110H. In the test pattern image 100, the sixth pattern 120F is positioned in the -X direction adjacent to the second mark 110B, the fourth mark 110D, the sixth mark 110F, and the eighth mark 110H.

[0064] The first pattern 120A, the second pattern 120B, the third pattern 120C, the fourth pattern 120D, the fifth pattern 120E, and the sixth pattern 120F are printed by different nozzle arrays. Figure 5 The first pattern 120A shown is printed using a magenta ink nozzle array 20M. The first pattern 120A is a magenta pattern. Figure 5 The second pattern 120B shown is printed using a 20LM bright magenta ink nozzle array. The second pattern 120B is a bright magenta pattern. Figure 5 The third pattern 120C shown is printed using cyan ink nozzle array 20C. The third pattern 120C is a cyan pattern. Figure 5 The fourth pattern 120D shown is printed using a bright cyan ink nozzle array 20LC. The fourth pattern 120D is a bright cyan pattern. Figure 5 The fifth pattern 120E shown is printed using yellow ink nozzles 20Y. The fifth pattern 120E is a yellow pattern. Figure 5 The sixth pattern 120F shown is printed by a black ink nozzle row 20K. The sixth pattern 120F is a black pattern. Pattern image 120 is printed by all nozzle rows. Each pattern is printed by all the ink nozzles 20 contained in each nozzle row.

[0065] Pattern 120A, Pattern 120B, Pattern 120C, Pattern 120D, Pattern 120E, and Pattern 120F can also be printed with colors different from those mentioned above. The colors of each pattern can be set appropriately.

[0066] Figure 6 It is an enlarged view of the test pattern image 100 containing the first mark 110A. Figure 6 This indicates a first mark 110A and a first pattern 120A adjacent to the first mark 110A. The first mark 110A corresponds to an example of a first position detection mark. Furthermore, Figure 6 This refers to the first measurement area 130A. The first measurement area 130A is one of a plurality of measurement areas 130. The measurement area 130 represents the range measured when the data processing unit 35 determines the positions of the plurality of marks contained in the test pattern image 100. Figure 6 The color of the first mark 110A shown is black. Black corresponds to an example of the first color. Figure 6 The first pattern 120A shown is composed of multiple line images 122. Figure 6 The color of the first pattern 120A shown is magenta. Magenta corresponds to an example of the second color. The first pattern 120A corresponds to an example of the second color inspection pattern.

[0067] The data processing unit 35 determines the position of each marker in the read data read by the read sensor 15. The data processing unit 35 uses a range of a predetermined size in the read data as a measurement area 130 and calculates the concentration distribution within the measurement area 130. The printing start position of the test pattern image 100 is controlled by the printing control unit 31. The reading start position based on the read sensor 15 is controlled by the read control unit 33. On the other hand, the printing medium M may not be conveyed to the predetermined position due to meandering, slippage of the feed roller pair 13, etc. The data processing unit 35 calculates, for example, the concentration distribution within the measurement area 130 of a predetermined size, thereby determining the position of each marker.

[0068] Figure 6 The first measurement region 130A shown represents the range used to measure the concentration distribution of the first label 110A. The first measurement region 130A refers to a region with a width of 130AW in the direction parallel to the X-axis and a length of 130AL in the direction parallel to the Y-axis. The first measurement region 130A corresponds to an example of the first region.

[0069] Figure 7 This indicates the concentration distribution in the first measurement region 130A. Figure 7 express Figure 6 The concentration distribution along the first imaginary line VL1 is shown. The first imaginary line VL1 is an imaginary line parallel to the X-axis. The data processing unit 35 measures the concentration distribution within a first measurement region 130A, including the concentration distribution along the first imaginary line VL1. Figure 7 This represents the first marker concentration distribution 160A corresponding to the first marker 110A and the first pattern concentration distribution 170A corresponding to the first pattern 120A.

[0070] As an example, the data processing unit 35 calculates the concentration centroid within the first measurement region 130A, thereby determining the position of the first marker 110A. The position of the first marker 110A corresponds to, for example, the first position of the first position detection marker. Figure 6 As shown, the first pattern 120A is included within the first measurement area 130A. Figure 7 As shown, the first pattern concentration distribution 170A is contained within the width 130AW of the first measurement area.

[0071] Figure 7 This represents the hypothetical first pattern density distribution 170AK. The hypothetical first pattern density distribution 170AK is the output value when printing the first pattern 120A using a black ink nozzle array 20K. The color of the first pattern 120A is black. When the color of the first pattern 120A is black, the density centroid position of the first measurement area 130A is as follows: Figure 7 As shown, this becomes the hypothetical center of gravity position P1A.

[0072] The color of the first pattern 120A is magenta, therefore the concentration distribution of the first pattern 170A is smaller than the hypothetical concentration distribution of the first pattern 170AK. The centroid of the concentration in the first measurement region 130A is as follows: Figure 7 As shown, the first mark centroid position P1 is defined. The first mark centroid position P1 corresponds to the first position of the first position detection mark. The color of the first mark 110A is different from the color of the first pattern 120A adjacent to the first mark 110A. Regarding the first mark centroid position P1, since the influence of the first pattern density distribution 170A is relatively small, the data processing unit 35 can determine the position of the first mark 110A more accurately. Furthermore, regarding the data processing unit 35, since the influence of the first pattern density distribution 170A is relatively small, the first measurement area 130A can be set wider. When the first measurement area 130A widens, the data processing unit 35 can reliably determine the position of the first mark 110A.

[0073] The data processing unit 35 analyzes the concentration distribution of the first mark 110A using the red channel contained in the read data. The red channel is the light-receiving data when the light-emitting part emits red light; therefore, the magenta first pattern 120A reflects more red light, while the black first mark 110A absorbs light. Thus, when the data processing unit 35 estimates the concentration distribution, for example, based on the reflected light printed onto the white printing medium M, the output value of the concentration distribution of the black first mark 110A increases. That is, the reflected light from the white printing medium M, which also reflects red light, mixes with the reflected light from the magenta first pattern A, so the output value of the concentration distribution of the first pattern A decreases. In other words, by using the red channel for analysis by the data processing unit 35, the output value of the first pattern concentration distribution 170A is further reduced. Red corresponds to an example of a color associated with magenta. The data processing unit 35 is able to suppress the influence of the magenta first pattern 120A adjacent to the first mark 110A. The red channel corresponds to an example of a first channel that extracts a color associated with a first color. Furthermore, for ease of understanding, a white printing medium M is shown as an example, but according to the above way of thinking, the reading sensor 15 only needs to read the color channel with a large gap between the reflected light of the first mark 110A and the reflected light of the first pattern 120A, so the color of the printing medium is not limited to white.

[0074] When analyzing the first magenta pattern 120A, the data processing unit 35 uses a green channel to extract the green component. By using the green channel, the data processing unit 35 can suppress the influence of adjacent patterns such as the second pattern 120B, and perform analysis with higher accuracy. Green corresponds to a color different from the color associated with the second color. The green channel corresponds to a second channel that extracts a color different from the color associated with the second color.

[0075] The data reading includes a red channel for extracting red. Preferably, the data processing unit 35 uses the red channel to analyze the first marker 110A. Furthermore, the data reading includes a green channel for extracting green, which is different from red. Preferably, the data processing unit 35 uses the green channel to analyze the first magenta pattern 120A.

[0076] When determining the position of the first mark 110A, the printing apparatus 10 is able to reduce the influence of the color of the first pattern 120A.

[0077] The color of the first mark 110A is not limited to black. The color of the first pattern 120A is not limited to magenta. For example, the first mark 110A can also be printed in magenta. The first pattern 120A can also be printed in cyan. The data processing unit 35 analyzes the first mark 110A using the green channel and analyzes the first pattern 120A using the red channel. Preferably, the data processing unit 35 appropriately selects the red channel, green channel, and blue channel for analysis based on the colors of the mark and pattern being analyzed.

[0078] When the data processing unit 35 performs analysis using the red, green, and blue channels, it is preferable that the colors of each pattern contained in the test pattern image 100 are pre-adjusted. For example, if the first pattern 120A is magenta, it is preferable that the second pattern 120B is cyan. Cyan is an example of a third color. It is preferable that the color of the second pattern 120B adjacent to the first pattern 120A is close to the complementary color of the first pattern 120A. The setter of the test pattern image 100 pre-sets the color of the second pattern 120B adjacent to the first pattern 120A to a color close to its complementary color. When the data processing unit 35 analyzes the first pattern 120A, it uses the green channel, thereby enabling analysis that suppresses the influence of the cyan second pattern 120B.

[0079] Figure 6 , Figure 7 The concentration distribution 160A of the first label is determined in the first measurement region 130A, but is not limited to this. The concentration distribution of any one of the second label 110B, the third label 110C, the fourth label 110D, the fifth label 110E, the sixth label 110F, the seventh label 110G, and the eighth label 110H is measured in the first measurement region 130A.

[0080] Figure 8 It is an enlarged view of the test pattern image 100 containing the second mark 110B. Figure 8 This indicates the second mark 110B and the sixth pattern 120F adjacent to the second mark 110B. The second mark 110B corresponds to an example of the second position detection mark. Furthermore, Figure 8 This indicates the second measurement region 130B. The second measurement region 130B is one of a plurality of measurement regions 130. Figure 8 The second mark 110B shown is black. Figure 8 The sixth pattern 120F shown is composed of multiple line images 122. Figure 8 The sixth pattern 120F shown is black.

[0081] Figure 8The second measurement region 130B shown represents the range for measuring the concentration distribution of the second label 110B. The second measurement region 130B refers to a region with a width of 130BW in the direction parallel to the X-axis and a length of 130BL in the direction parallel to the Y-axis. The second measurement region 130B corresponds to an example of the second region.

[0082] The second measurement region 130B is smaller than the first measurement region 130A. Figure 8 The width of the second measurement area, 130 BW, is shorter than the width of the first measurement area, 130 AW. Figure 8 The length of the second measurement region 130BL shown is shorter than the length of the first measurement region 130AL. The area of ​​the second measurement region 130B is smaller than the area of ​​the first measurement region 130A.

[0083] The storage unit 37 pre-stores test pattern data. The test pattern data includes information about the relative positions of each mark and each pattern. The data processing unit 35, by determining the position of the first mark 110A, can estimate the position of the second mark 110B with high accuracy. The data processing unit 35 can determine the position of the second mark 110B within a second measurement area 130B that is smaller than the first measurement area 130A. The position of the second mark 110B corresponds to an example of the second position of a second position detection mark.

[0084] Figure 9 This indicates the concentration distribution of B in the second measurement region 130B. Figure 9 express Figure 8 The concentration distribution along the second imaginary line VL2 is shown. The second imaginary line VL2 is an imaginary line parallel to the X-axis. The data processing unit 35 measures the concentration distribution within the second measurement region 130B, including the concentration distribution along the second imaginary line VL2. Figure 9 This represents the second marker concentration distribution 160B corresponding to the second marker 110B and the sixth pattern concentration distribution 170F corresponding to the sixth pattern 120F.

[0085] As an example, the data processing unit 35 calculates the concentration centroid within the second measurement region 130B, thereby determining the position of the second marker 110B. For example... Figure 8 As shown, the sixth pattern 120F is not included within the second measurement area 130B. (As indicated...) Figure 9 As shown, the sixth pattern concentration distribution 170F is not included within the second measurement area width 130 BW. The data processing unit 35 is able to determine the second marker centroid position P2 with good accuracy.

[0086] The second measurement area 130B is smaller than the first measurement area 130A, so the data processing unit 35 is less affected by the sixth pattern 120F adjacent to the second mark 110B. Furthermore, the setter of the test pattern image 100 can set the color of the sixth pattern 120F adjacent to the second mark 110B to black.

[0087] Figure 8 , Figure 9 The second label concentration distribution 160B is determined in the second measurement region 130B, but is not limited thereto. When the position of the first label 110A is determined in the first measurement region 130A, the positions of the third label 110C, the fourth label 110D, the fifth label 110E, the sixth label 110F, the seventh label 110G, and the eighth label 110H can also be determined in the measurement region 130, which is the same size as the second measurement region 130B.

[0088] As described above, the printing apparatus 10 includes: a printing mechanism 16 for printing a test pattern image 100; a reading sensor 15 for reading the test pattern image 100 printed by the printing mechanism 16; and a data processing unit 35 for analyzing the reading data read by the reading sensor 15. The test pattern image 100 has a pattern image 120 of multiple colors, including a first mark 110A printed in black, a second mark 110B printed in black, and a first pattern 120A printed in magenta, a color different from black. The printing mechanism 16 prints the first pattern 120A at a position adjacent to the first mark 110A. The data processing unit 35 determines the position of the first mark 110A in a first measurement area 130A. The data processing unit 35 determines the position of the second mark 110B in a second measurement area 130B that is smaller than the first measurement area 130A.

[0089] When determining the position of the first mark 110A, the printing apparatus 10 can reduce the influence of the first pattern 120A. Furthermore, when determining the position of the second mark 110B, the printing apparatus 10 can reduce the influence of the sixth pattern 120F. The printing apparatus 10 can accurately determine the positions of the first mark 110A and the second mark 110B.

[0090] Figure 6 , Figure 8 A circular image of a specified size is shown as a first mark 110A and a second mark 110B. The shapes of the first mark 110A and the second mark 110B are not limited to circular images. The shapes of the first mark 110A and the second mark 110B can also be, for example, marks of a specified shape such as a dragonfly with two intersecting lines. The data processing unit 35 estimates the shape of the mark based on the output value of the read data. The data processing unit 35 can also determine the position of the mark based on the estimated shape of the mark.

[0091] The preferred data processing unit 35 determines the positions of the first mark 110A and the second mark 110B by calculating the density distribution of the marks. The data processing unit 35 can easily determine the positions of the first mark 110A and the second mark 110B. By calculating the mark positions based on the density distribution of the marks using the data processing unit 35, the designer of the test pattern image 100 can use a circular image as the mark image 110. When the mark image 110 is tilted during printing, the data processing unit 35 is less susceptible to the effects of tilt.

[0092] The data processing unit 35 of the printing apparatus 10 determines the position of the first mark 110A based on the black concentration distribution in the first measurement area 130A, and determines the position of the second mark 110B based on the black concentration distribution in the second measurement area 130B.

[0093] The printing apparatus 10 determines the position of the first mark 110A and the position of the second mark 110B based on the concentration distribution, thus enabling accurate position determination.

[0094] Figure 5 The test pattern image 100 shown is printed in the following order in a direction parallel to the X-axis: first mark 110A, first pattern 120A, second pattern 120B, third pattern 120C, fourth pattern 120D, fifth pattern 120E, sixth pattern 120F, and second mark 110B. The first mark 110A and the second mark 110B are sandwiched between the pattern image 120 during printing. By positioning the first mark 110A and the second mark 110B within the sandwiched pattern image 120, the accuracy of determining the position of each image in the pattern image 120 is improved.

[0095] The printing mechanism 16 of the printing apparatus 10 prints a pattern image 120 between the first mark 110A and the second mark 110B in a direction parallel to the X-axis.

[0096] Figure 10 A flowchart illustrating the image processing performed by the printing apparatus 10. Figure 10 The image processing method shown is performed by executing a printing control program by the control unit 30. The printing control program corresponds to an example of the image processing program.

[0097] In step S101, the printing apparatus 10 prints the test pattern image 100. The printing apparatus 10 prints the test pattern image 100 based on the test pattern data stored in the storage unit 37. The test pattern image 100 is as follows: Figure 5As shown, it has a first mark 110A, a second mark 110B, and a pattern image 120. The first mark 110A is printed by a black ink nozzle line 20K. The first mark 110A is black. The second mark 110B is printed by a black ink nozzle line 20K. The second mark 110B is black.

[0098] The test pattern image 100 has a third mark 110C, a fourth mark 110D, a fifth mark 110E, a sixth mark 110F, a seventh mark 110G, and an eighth mark 110H. The third mark 110C, fourth mark 110D, fifth mark 110E, sixth mark 110F, seventh mark 110G, and eighth mark 110H are printed using a black ink nozzle line 20K. The third mark 110C, fourth mark 110D, fifth mark 110E, sixth mark 110F, seventh mark 110G, and eighth mark 110H are black.

[0099] Pattern image 120 includes a first pattern 120A, a second pattern 120B, a third pattern 120C, a fourth pattern 120D, a fifth pattern 120E, and a sixth pattern 120F. The first pattern 120A is printed using a magenta ink nozzle line 20M. The first pattern 120A is a magenta pattern. The second pattern 120B is printed using a bright magenta ink nozzle line 20LM. The second pattern 120B is a bright magenta pattern. The third pattern 120C is printed using a cyan ink nozzle line 20C. The third pattern 120C is a cyan pattern. The fourth pattern 120D is printed using a bright cyan ink nozzle line 20LC. The fourth pattern 120D is a bright cyan pattern. The fifth pattern 120E is printed using a yellow ink nozzle line 20Y. The fifth pattern 120E is a yellow pattern. The sixth pattern 120F is printed using a black ink nozzle line 20K. The sixth pattern 120F is a black pattern.

[0100] The first pattern 120A is positioned adjacent to the first mark 110A, the third mark 110C, the fifth mark 110E, and the seventh mark 110G. The sixth pattern 120F is positioned adjacent to the second mark 110B, the fourth mark 110D, the sixth mark 110F, and the eighth mark 110H.

[0101] After printing the test pattern image 100, the printing apparatus 10 reads the test pattern image 100 via the read sensor 15 in step S103. The read sensor 15 reads the test pattern image 100 and generates read data. The read data includes the red channel, green channel, and blue channel. The data processing unit 35 acquires the read data generated by the read sensor 15.

[0102] After acquiring the read data, the printing apparatus 10 determines the position of the first mark 110A in step S105. The position of the first mark 110A is the printing position on the printing medium M. The data processing unit 35 estimates the position of the first mark 110A based on the printing control data used by the printing control unit 31. The printing control data is control data generated based on test pattern data, which serves as printing data. The data processing unit 35 measures the black concentration distribution within a first measurement area 130A, including the estimated position. The first measurement area 130A is as follows: Figure 6 The area shown has a first measurement region width of 130AW and a first measurement region length of 130AL. The data processing unit 35 calculates the centroid of the black concentration distribution. The data processing unit 35 determines the position of the first mark 110A by calculating the centroid of the concentration.

[0103] After determining the position of the first mark 110A, the printing apparatus 10 determines the position of the second mark 110B in step S107. The position of the second mark 110B is the printing position on the printing medium M. The data processing unit 35 estimates the position of the second mark 110B based on the determined position of the first mark 110A. The data processing unit 35 measures the black concentration distribution within a second measurement area 130B, including the estimated position. The second measurement area 130B is as follows: Figure 8 The area shown has a second measurement region width 130BW and a second measurement region length 130BL. The second measurement region 130B is smaller than the first measurement region 130A. The position of the second mark 110B is estimated based on the determined position of the first mark 110A, so the estimated position of the second mark 110B is estimated with high accuracy. Even when the second measurement region 130B is smaller than the first measurement region 130A, the data processing unit 35 can still determine the position of the second mark 110B. The data processing unit 35 calculates the concentration centroid of the black concentration distribution. The data processing unit 35 determines the position of the second mark 110B by calculating the concentration centroid.

[0104] The position of the first mark 110A is determined based on the concentration distribution of black within the first measurement area 130A, and the position of the second mark 110B is determined based on the concentration distribution of black within the second measurement area 130B.

[0105] The printing apparatus 10 determines the position of the first mark 110A and the position of the second mark 110B based on the concentration distribution, thereby enabling accurate position determination.

[0106] The printing device 10 can also determine the position of the third mark 110C. Figure 11 It is an enlarged view of the test pattern image 100 containing the third mark 110C. Figure 11This indicates a third mark 110C and a first pattern 120A adjacent to the third mark 110C. The first pattern 120A is composed of multiple line images 122. The third mark 110C corresponds to an example of a third position detection mark. The position of the third mark 110C corresponds to an example of a third position of the third position detection mark. The position of the third mark 110C is a printing position on the printing medium M. The data processing unit 35 estimates the position of the third mark 110C based on the determined position of the first mark 110A. The data processing unit 35 measures the black concentration distribution within a third measurement area 130C, including the estimated position. The third measurement area 130C is as follows: Figure 11 The area shown has a third measurement region width 130CW and a third measurement region length 130CL. The third measurement region 130C corresponds to an example of the third region. The third measurement region 130C may also be the same size as the second measurement region 130B. The width 130CW of the third measurement region may also be the same width as the width 130BW of the second measurement region. The length 130CL of the third measurement region may also be the same length as the length 130BL of the second measurement region. The third measurement region 130C is smaller than the first measurement region 130A. The position of the third mark 110C is estimated based on the determined position of the first mark 110A, so the estimated position of the third mark 110C is estimated with high accuracy. Even when the third measurement region 130C is smaller than the first measurement region 130A, the data processing unit 35 can still determine the position of the third mark 110C. The data processing unit 35 calculates the concentration centroid of the black concentration distribution. The data processing unit 35 determines the position of the third mark 110C by calculating the concentration centroid.

[0107] The printing device 10 determines the positions of the fourth mark 110D, the fifth mark 110E, the sixth mark 110F, the seventh mark 110G, and the eighth mark 110H in the same manner as the third mark 110C.

[0108] The printed test pattern image 100 has a third mark 110C that is different from the first mark 110A and the second mark 110B. The printing apparatus 10 determines the position of the third mark 110C in a third measurement area 130C that is smaller than the first measurement area 130A. Preferably, the printing apparatus 10 determines the position of the third mark 110C in a third measurement area 130C that is the same size as the second measurement area 130B.

[0109] The printing apparatus 10 is able to suppress the influence of the first pattern 120A adjacent to the third mark 110C and detect the position of the third mark 110C.

[0110] After determining the position of the second mark 110B, the printing apparatus 10 performs a defective nozzle determination in step S109. The data processing unit 35 determines the position of each line image 122 within the pattern image 120 based on the determined positions of the first mark 110A and the second mark 110B. The data processing unit 35 compares the determined positions of each line image 122 with a pre-estimated reference position for each line image 122. The data processing unit 35 determines a defective nozzle based on the difference between the determined positions of each line image 122 and the pre-estimated reference positions for each line image 122. The data processing unit 35 determines the position of each line image 122 based on the first mark 110A and the second mark 110B. The data processing unit 35 can determine the position of each line image 122 with high accuracy. The printing apparatus 10 can not only determine the non-ejection of ink from the ink nozzle 20, but also determine the flight curvature of the ink ejected from the ink nozzle 20.

[0111] The test pattern image 100 is printed such that the first pattern 120A is arranged at a position adjacent to the first mark 110A. The test pattern image 100 is read and the read data is acquired. The position of the first mark 110A is determined in the first measurement area 130A. The position of the second mark 110B is determined in the second measurement area 130B, which is smaller than the first measurement area 130A. The test pattern image 100 has a first mark 110A formed of black, a second mark 110B formed of black, and a pattern image 120 of multiple colors including the first pattern 120A formed of magenta, which is different from black.

[0112] When determining the position of the first mark 110A, the printing apparatus 10 can reduce the influence of the color of the first pattern 120A. Furthermore, when determining the position of the second mark 110B, the printing apparatus 10 can reduce the influence of the sixth pattern 120F. The printing apparatus 10 can accurately determine the positions of the first mark 110A and the second mark 110B.

[0113] A printing control program executed by the control unit 30 of a printing apparatus 10 for printing a test pattern image 100 causes the printing control program to print the test pattern image 100 in such a way that the first pattern 120A is arranged at a position adjacent to the first mark 110A, read the test pattern image 100 and acquire read data, determine the position of the first mark 110A in a first measurement area 130A, and determine the position of the second mark 110B in a second measurement area 130B that is smaller than the first measurement area 130A. The test pattern image 100 has a first mark 110A formed of black, a second mark 110B formed of black, and a pattern image 120 of multiple colors including the first pattern 120A formed of magenta, which is different from black.

[0114] When determining the position of the first mark 110A, the printing apparatus 10 can reduce the influence of the color of the first pattern 120A. Furthermore, when determining the position of the second mark 110B, the printing apparatus 10 can reduce the influence of the sixth pattern 120F. The printing apparatus 10 can accurately determine the positions of the first mark 110A and the second mark 110B.

[0115] Pattern image 120 is not limited to Figure 5 The pattern shown is a stepped pattern. The form of pattern image 120 can be appropriately modified as long as it is a grayscale image used for evaluating colors or an image used in the evaluation by the printing apparatus 10. In this case, the image adjacent to the marker image 110 only needs to be an image of a different color from the marker image 110.

[0116] The term "adjacent" in this specification does not necessarily mean a position that is directly next to each other. Furthermore, it does not necessarily mean that the marked image 110 and the evaluation image are adjacent in the X direction as shown in the diagram. As long as the marked image 110 and the evaluation image are somewhat close, and their positional relationship or color influence reduces the detection accuracy of the marked image 110, they are considered adjacent.

Claims

1. A liquid ejection device, characterized in that, have: Printing department, printing and inspecting images; The reading unit reads the inspection image printed by the printing unit; and The analysis unit performs analysis based on the reading results obtained by the reading unit. The inspection image has a first position detection mark printed with a first color, a second position detection mark printed with the first color, and an inspection pattern comprising a second color inspection pattern printed with a second color different from the first color. The printing section prints the second color inspection pattern at a position adjacent to the first position detection mark. The analysis unit uses a first channel for extracting a color related to the second color to determine the first position of the first position detection mark in a first region including the first position detection mark and a portion of the inspection pattern. The second position of the second position detection mark is determined in a second region that is smaller than the first region.

2. The liquid ejection device according to claim 1, characterized in that, The printing unit prints the inspection pattern in a manner that places it between the first position detection mark and the second position detection mark in a predetermined direction.

3. The liquid ejection device according to claim 1 or 2, characterized in that, The analysis unit determines the first position based on the concentration distribution of the first color within the first region. The analysis unit determines the second position based on the concentration distribution of the first color within the second region.

4. The liquid ejection device according to claim 1, characterized in that, The inspection image has a third-color inspection pattern printed with a third color different from the second color. The reading result has a second channel that extracts a color that is different from the color associated with the second color. The analysis unit uses the second channel to analyze the second color inspection pattern.

5. An image processing method, characterized in that, An inspection image is printed by means of a first position detection mark formed with a first color, a second position detection mark formed with the first color, and an inspection pattern comprising an inspection pattern of multiple colors, including a second color inspection pattern formed with a second color different from the first color, by arranging a second color inspection pattern at a position adjacent to a first position detection mark. Read the inspected image and obtain the reading result. In a first region including the first location detection mark and a portion of the inspection pattern, a first channel for extracting a color associated with the second color is used to determine the first location of the first location detection mark. The second position of the second position detection mark is determined in a second region that is smaller than the first region.

6. The image processing method according to claim 5, characterized in that, The printed inspection image has a third position detection mark that is different from the first position detection mark and the second position detection mark. A third position corresponding to the third position detection mark is determined in a third region that is smaller than the first region.

7. The image processing method according to claim 6, characterized in that, The second region and the third region are the same size.

8. The image processing method according to any one of claims 5 to 7, characterized in that, The first position is determined based on the concentration distribution of the first color within the first region. The second position is determined based on the concentration distribution of the first color within the second region.

9. An image processing program, characterized in that, The process is executed by the processor of the liquid ejection device for printing and inspecting images. The image processing program performs the following processing: The inspection image is printed by arranging a second color inspection pattern at a position adjacent to the first position detection mark. The second position detection mark is formed with the first color, and the inspection pattern comprises an inspection pattern in multiple colors, including the first position detection mark, the second position detection mark formed with the first color, and the second color inspection pattern formed with a second color different from the first color. Read the inspected image and obtain the reading result. In a first region including the first location detection mark and a portion of the inspection pattern, a first channel for extracting a color associated with the second color is used to determine the first location of the first location detection mark. The second position of the second position detection mark is determined in a second region that is smaller than the first region.

Images