Recording device, recording method, and program

Abstract

To appropriately adjust a recording position even when a test chart recorded on a recording medium is read in parts.SOLUTION: A print controller converts a representative position of a patch corresponding to each of recording element substrates for a first read image and a second read image into differential position information from an original point positioned in an overlapping region of each read image. The print controller converts differential position information of the second read image so that a degree K of shrinkage becomes 1 on the basis of the differential position information and the degree of shrinkage of the second read image. Conversion such that the degree of shrinkage becomes 1 means such conversion that a distance between specific patterns in the second read image becomes equal to a distance between corresponding same specific patterns in the first read image. The print controller calculates an inclination of a reference line for calculating a deviation amount between the recording element substrates with respect to the first read image.SELECTED DRAWING: Figure 18

Description

Technical Field

[0001] The present invention relates to a control technique for adjusting a recording position in a recording apparatus.

Background Art

[0002] There is known a recording apparatus that uses a so-called full-line type recording head having a recording width corresponding to the width of a recording medium. One such recording apparatus is an inkjet recording apparatus. In a full-line type inkjet recording apparatus, a plurality of recording element substrates each including a plurality of nozzle rows are arranged, and an image can be recorded on substantially the entire surface of the recording medium by relatively moving the recording medium once. In a recording apparatus provided with a full-line type recording head, an error may occur in the mounting position of the recording head or the relative mounting positions between a plurality of recording heads. This error causes a shift in the adhesion position of the recording material (ink landing position in the case of an inkjet recording apparatus) on the recording medium, which is a factor in reducing the recording quality. Hereinafter, the process of correcting such a shift in the adhesion position of the recording material is referred to as "recording position adjustment".

[0003] In recording position adjustment, a test chart recorded on a recording medium is read using a scanner device equipped with an image sensor, and first, the positions of patches corresponding to the nozzle rows and the recording element substrates included in the test chart are detected from the read image. Then, the relative positions between those patterns are obtained, and the recording position is adjusted based on this relative position. As a method for improving the position detection accuracy of the patches, Patent Document 1 discloses a method of performing recording position adjustment based on the amount of deviation between the recording element substrates obtained from the distances between each recording element substrate and a reference line connecting the estimated positions of two recording element substrates close to both ends of the recording head.

[0004] When performing large-format printing with an inkjet recording apparatus using a full-line type recording head, the recording head needs to be enlarged according to the recording medium. When the recording head becomes larger, the test chart for recording position adjustment also becomes larger, so the scanner device requires a reading size corresponding to the size of the test chart. There are also scanner devices with a large reading size that combine multiple image sensors.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when using a scanner device that combines multiple image sensors in the technology described in Patent Document 1, the positions of two recording element substrates close to both ends of the recording head for obtaining a reference line are estimated based on two read images with different reading conditions. As a result, the estimation accuracy of the relative positions of the two recording element substrates for obtaining the reference line decreases, and the accuracy of the reference line also decreases, so that the recording position adjustment cannot be properly performed.

[0007] Therefore, an object of the present invention is to properly perform recording position adjustment even when a test chart recorded on a recording medium is read in a divided manner.

Means for Solving the Problems

[0008] The present invention relates to a recording apparatus having one or more recording means including a plurality of recording element substrates to which a recording material is applied, the recording means including reading control means for causing a reading device to read by dividing a test chart including a plurality of patches corresponding to each of the recording element substrates printed on a recording medium with a plurality of optical sensors, calculating means for calculating a stretching ratio of patches corresponding to a recording element substrate included in the same recording means for a pair of reading images composed of two of the plurality of reading images based on the plurality of reading images obtained by causing the reading device to read the test chart printed on the recording medium, and adjusting means for adjusting an adhesion position of the recording material applied from the recording means based on the stretching ratio calculated by the calculating means and position information of the patches in the plurality of reading images.

Effects of the Invention

[0009] According to the present invention, even when a test chart recorded on a recording medium is read after being divided, it is possible to appropriately adjust the recording position.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] This embodiment will be described with reference to the drawings. Note that the components described in this embodiment show a form as an example of the present invention, and the scope of the present invention is not limited only to them.

[0012] FIG. 1 is a front view schematically showing an inkjet recording apparatus 100 according to the present embodiment. The inkjet recording apparatus 100 is an apparatus for printing on a continuous paper (hereinafter referred to as a roll paper) 110 that enables continuous printing used in the present embodiment. In the present embodiment, the inkjet recording apparatus 100 includes a paper feeding device 103 for transporting the roll paper 110, a main unit 111 for performing printing, a paper discharging device 104 for winding up the roll paper 110, and an operation panel 101.

[0013] The paper feeding device 103 is a device for supplying the roll paper 110 to the main unit 111. The paper feeding device 103 rotates the paper tube of the roll paper 110 around the rotating shaft 112, and transports the roll paper 110 wound around the paper tube to the inkjet recording apparatus 100 at a constant speed via a plurality of rollers (such as a conveying roller and a paper feeding roller).

[0014] The paper discharging device 104 is a device for winding up the roll paper 110 conveyed from the main unit 111 in a roll shape around the paper tube. The paper discharging device 104, for example, as shown in the figure, holds the roll paper 110 wound around the paper tube of the rotating shaft 113 in a roll shape. The paper discharging device 104 rotates around the rotating shaft 113 and winds up the roll paper 110 conveyed to the paper tube at a constant speed via a plurality of rollers (for example, a conveying roller and a paper discharging roller) as a result of the roll paper. Before the start of printing, the roll paper 110 is passed from the paper feeding device 103 to the paper discharging device 104. The roll paper 110 is set in the paper feeding device 103, and the leading end of the roll paper 110 is passed over the skew correction device 109. Next, it passes under the recording head 102 of the inkjet recording method of the main unit 111, under the drying device 105, over the cooling devices 107 and 108, through the scanner device 106, and is wound up by the paper discharging device 104.

[0015] In the scanner device 106, an optical sensor is used to optically read a printed pattern or the like printed on a roll paper. After passing the roll paper 110 through the inkjet recording device 100, a print job is input to the control PC 114 of the inkjet recording device 100. After inputting the print job, the print start button is pressed on the operation panel 101 to start printing.

[0016] FIG. 2 is a top view from above the scanner device when the scanner device 106 reads a test chart. The recording medium P, which is the roll paper 110, is conveyed in the conveyance direction 201, the conveyance speed is adjusted in the vicinity of the scanner device 106, and imaging of the imaging area 203 is performed using the sensors 202A and 202B, which are optical sensors. The sensors 202A and 202B are arranged in a staggered configuration such that a part of the imaging area overlaps the side surface of the scanner device 106 facing the recording medium P. Due to such a staggered arrangement, the sensors 202A and 202B are arranged at intervals from each other along the conveyance direction 201. Further, the sensors 202A and 202B include imaging elements (not shown) such as a CCD sensor or a CMOS sensor. The read image of the imaging area 203 obtained by the scanner device 106 is used for calculating various correction values. The method for calculating the correction values will be described later. Note that the scanner device 106 may be configured to be installed in advance in the main unit 111 or may be configured to be attachable as an option.

[0017] FIG. 3 is a block diagram showing the hardware configuration for controlling the inkjet recording device 100. The control configuration is mainly composed of a print engine unit 400 that generalizes the print engine and a controller unit 300 that generalizes the entire inkjet recording device. The print controller 402 controls various mechanisms of the print engine unit 400 according to the instructions of the main controller 301 of the controller unit 300. The details of the control configuration will be described below.

[0018] In the controller unit 300, the main controller 301 composed of a CPU controls the entire inkjet recording apparatus 100 while using the RAM 305 as a work area according to the programs and various parameters stored in the ROM 306. For example, when a print job is input from the host device 500 via the host I / F 302, the image processing unit 307 performs predetermined image processing on the received image data according to the instructions of the main controller 301. Then, the main controller 301 transmits the image data subjected to the image processing to the print engine unit 400 via the print engine I / F 304.

[0019] Incidentally, the inkjet recording apparatus 100 may acquire the image data to be transmitted to the print engine unit 400 from an external storage device (such as a USB memory) connected to the inkjet recording apparatus 100. The operation panel 303 is a mechanism for the user to perform input / output operations on the recording apparatus. The user can instruct operations such as printing and paper feeding, set the print mode, and recognize information on the recording apparatus via the operation panel 303. The operation panel 303 is a touch panel, and it is also possible to connect a mouse or a keyboard for input.

[0020] In the print engine unit 400, a print controller 402 composed of a CPU controls various mechanisms provided in the inkjet recording apparatus 100 according to programs and various parameters stored in a ROM 403. At this time, the print controller 402 uses a RAM 404 as a work area. When various commands and image data are received via a controller I / F 401, the print controller 402 temporarily stores them in the RAM 404. So that the recording head 102 can be used for the recording operation, the print controller 402 causes an image processing controller 405 to convert the image data stored in the RAM 404 into recording data. When the recording data is generated, the print controller 402 causes the recording head 102 to execute a recording operation based on the recording data via a head I / F 406. At this time, the print controller 402 drives a paper feeding device 103 and a paper discharging device 104 shown in FIG. 1 via a conveyance control unit 407 to convey a roll paper 110 which is a recording medium. Also, the print controller 402 drives a heater and a fan of a drying device 105 and cooling devices 107 and 108 via the conveyance control unit 407 to dry and cool the conveyed paper. Further, the conveyance control unit 407 can detect a conveyance amount from an encoder provided in a conveyance roller. In accordance with an instruction of the print controller 402, a recording operation by the recording head 102 is executed in conjunction with the conveyance operation of the roll paper, and printing processing is performed.

[0021] The recording head 102 is configured to be able to move up and down (in a direction perpendicular to the recording surface of the roll paper 110). When printing, it descends, but it rises upward during maintenance or the like. A head carriage control unit 408 changes the vertical position of the recording head 102 according to an operation state such as a maintenance state or a recording state of the inkjet recording apparatus 100. An ink supply control unit 409 controls an ink supply unit so that the pressure of the ink supplied to the recording head 102 is within an appropriate range. When performing a maintenance operation on the recording head 102, a maintenance control unit 410 moves a maintenance unit under the head that has been raised, and controls maintenance operations of the head such as capping and wiping.

[0022] The scanner control unit 411 controls the scanner device 106. When the image data for which the recording operation is to be executed is a test chart that is a pattern for calculating various correction values, the print controller 402 instructs the conveyance control unit 407 to adjust the conveyance speed. Further, the scanner control unit 411, which is instructed by the print controller 402 about the reading timing of the test chart recorded on the roll paper, causes the scanner device 106 to capture an image and saves the captured image in the RAM 404. The various correction value calculation processes using the saved captured image are executed by the print controller 402. The obtained correction values are reflected in the recording operation by being passed from the print controller 402 to the image processing controller 405. Incidentally, the saved captured image may be transferred to the host device 500 via the controller unit 300, various correction value calculation processes may be performed, and the obtained correction values may be output to the print controller 402.

[0023] Hereinafter, details of a method for correcting the positional deviation of the recording head, which is one of the various correction values, will be described.

[0024] (Method for correcting the positional deviation of the recording head) FIG. 4 is a diagram showing the correspondence between patches 1007 and 1016 corresponding to one of the recording element substrates 1002 constituting the recording head 102 and the nozzles. The recording head 102 is composed of a plurality of recording element substrates 1002. The recording element substrate 1002 is composed of a plurality of nozzles, and each nozzle is configured to be able to eject ink by driving a recording element. The recording element for ejecting ink may be a heater or a piezo element. In the present embodiment, an example is shown in which a plurality of nozzle rows are arranged in the shape of a parallelogram on the recording element substrate. The nozzle arrangement direction 1001, which is the direction in which a plurality of nozzles are arranged, intersects the conveyance direction 201 and corresponds to the width direction of the recording medium. In 1006, which is an enlarged view of the recording element substrate 1002, the recording element substrate 1002 includes a plurality of nozzle rows 1005, and one nozzle row 1005 is composed of a plurality of nozzles. A test chart for one recording element substrate 1002 is recorded using the nozzles within the range sandwiched by the broken lines 1003 and 1004 of each nozzle row 1005 included in the recording element substrate 1002. This range may vary depending on the configuration of the recording element substrate 1002.

[0025] In the present embodiment, an example is shown in which the recording head is composed of 17 recording element substrates 1002, and each recording element substrate 1002 is composed of 16 rows of nozzle rows 1005. Also, each nozzle row is composed of 512 nozzles. Note that the number of recording element substrates 1002 constituting the recording head, the number of nozzle rows 1005 constituting the recording element substrate 1002, and the number of nozzles constituting each nozzle row 1005 are not limited to this.

[0026] For the sake of simplicity, the n-th (n ≧ 0) recording element substrate 1002 counted from the left in the nozzle array direction 1001 is called Cn, and the n-th (n ≧ 0) nozzle row 1005 counted from the downstream side in the conveyance direction 201 is called Rn. For example, since the recording element substrate 1031 is located at the left end in the nozzle array direction 1001, it is C0, and since the recording element substrate 1032 is located at the right end, it is C16. Also, since the nozzle row 1005 is located at the most upstream side in the conveyance direction 201, it is R15, and the nozzle row 1033 located at the most downstream side is R0. The nozzle row 1033 is composed of 512 nozzles (not shown) with the nozzle 1034 as the left end nozzle and the nozzle 1035 as the right end nozzle. Other nozzle rows are also composed of 512 nozzles in the same way.

[0027] The patch 1007 is one of the patches corresponding to one recording element substrate 1002. It is configured to include the detection mark 1019, the alignment mark 1020, and the pattern 1008 for pattern matching.

[0028] The pattern 1008 for pattern matching included in the patch 1007 is provided corresponding to each of a plurality of nozzle arrays. Here, the pattern 1008 for pattern matching is recorded using a different nozzle array 1005 respectively. That is, for 16 nozzle arrays 1005, the patterns 1008 for pattern matching from 0 to 15 are provided. The layout 1012 shows the arrangement of each pattern 1008 for pattern matching for each nozzle array 1005. In the rectangle 1010 corresponding to each pattern 1008 for pattern matching, a numerical value indicating the nozzle array 1005 that records the pattern 1008 for pattern matching at that position is described. For example, in the rectangle 1010 corresponding to the pattern 1008 for pattern matching recorded by the nozzle array 1005 of R0, "0" is described. In this way, the number described in the rectangle is the numerical value n of Rn indicating the nozzle array 1005 that records the pattern 1008 for pattern matching corresponding to that rectangle. Based on the pattern 1008 for pattern matching recorded by the nozzle array 1005 of R0, the positional deviation is calculated from the relative position with each pattern 1008 for pattern matching recorded by other nozzle arrays 1005. As an exception, a pattern 1008 for pattern matching corresponding to the rectangle 1011 is provided. This is the pattern 1008 for pattern matching recorded by the nozzle array 1005 of R12 among the nozzles included in the recording element substrate 1002 that is Cn + 1, which is the right adjacent recording element substrate 1002 when the recording element substrate 1002 is Cn. Note that the nozzle array 1005 of the adjacent recording element substrate 1002 that records the pattern 1008 for pattern matching corresponding to the rectangle 1011 is not limited to R12. The nozzle array 1005 that records the pattern 1008 for pattern matching corresponding to the rectangle 1011 may vary depending on the number of nozzle arrays 1005 constituting the recording element substrate 1002, the shape of the recording element substrate 1002, and the like.

[0029] Also, the area represented in black is the area recorded with the corresponding ink. Also, the area represented in white is the base color of the recording medium and is the area not recorded with ink.

[0030] From the pattern 1008 for pattern matching for each nozzle row 1005 in each patch 1007, the displacement of the nozzle row 1005 due to manufacturing errors in the recording element substrate 1002 on which the patch 1007 is recorded is calculated. Details will be described later with reference to FIG. 8. Note that the pattern for pattern matching corresponding to the rectangle 1011 is recorded on a recording element substrate 1002 different from the other patterns 1008 for pattern matching, and is not used for calculating the displacement of the nozzle row 1005 for each recording element substrate 1002.

[0031] The displacement between the recording element substrates 1002 and the inclination of the recording head 102 are also calculated using the patch 1007. The displacement between a plurality of recording element substrates 1002 within the same recording head 102 and the inclination of the recording head 102 are calculated based on a line segment connecting the representative position of the patch 1007 one inside from the left end and the representative position of the patch 1007 one inside from the right end. Details will be described later with reference to FIGS. 9 and 10.

[0032] Note that in the apparatus according to the present embodiment, the size of the recording medium 1201 is variable. Therefore, at the left end or the right end of the recording medium 1201, a part of the patch 1007 may be recorded in a missing state. When such a part of the patch 1007 is missing and the patch 1007 is recorded with a length equal to or greater than the detection mark 1019, the left end selects the pattern 1008 for pattern matching corresponding to the rectangle 1010 as the pattern for calculation. The right end selects the pattern 1008 for pattern matching corresponding to the rectangle 1011 as the pattern for calculation.

[0033] Depending on the recording head 102, in addition to the patch 1007, a patch 1016 may be recorded as a patch for each recording element substrate 1002. The patch 1016 is configured to include a detection mark 1023, an alignment mark 1024, and a pattern 1017 for pattern matching. Each pattern 1017 for pattern matching is recorded by a plurality of nozzle rows 1005. The P in the layout 1018 indicates that it is recorded by a plurality of nozzle rows 1005. Using this patch 1016, the inclination of the recording head 102 that recorded the patch 1016 is calculated.

[0034] The patches 1007 and 1016 for each recording element substrate 1002 are recorded so as to shift the recording timing to the recording medium by an amount that takes into account the intersection of the manufacturing error of the nozzle row 1005 and the manufacturing error of the recording element substrate 1002, so that there is no overlap of the test charts due to errors.

[0035] The detection marks 1019 and 1023 are used to detect the patches 1007 and 1016 corresponding to the recording element substrate 1002 in the read image by image analysis processing. Each detection mark 1019 and 1023 is a pattern recorded in the shape of a rectangular area.

[0036] In the present embodiment, each detection mark 1019 and 1023 is recorded by droplet ejection using a plurality of nozzle rows 1005. By recording using a plurality of nozzle rows 1005, even if there is a non-ejecting nozzle in a specific nozzle row 1005, droplets are ejected by the nozzles of other nozzle rows 1005, so that it is difficult for a detection pattern to be missing due to the non-ejecting nozzle. As a result, the detection marks 1019 and 1023 can be stably detected in the image analysis processing.

[0037] Alignment marks 1020 and 1024 are used to calculate the reference positions of the analysis regions of the patterns 1008 and 1017 for pattern matching by image analysis processing. Each alignment mark 1020 and 1024 is recorded in the shape of a rectangular region. Each alignment mark 1020 and 1024 is recorded by droplet ejection of a plurality of nozzle rows 1005 for each pattern 1008 and 1017 for pattern matching corresponding to each nozzle row 1005.

[0038] The patterns 1008 and 1017 for pattern matching are also used to detect the misalignment of the recording head 102 by image analysis processing. However, depending on the ink color of the recording head 102 and the type of misalignment amount to be calculated, the patches 1007 and 1016 are used appropriately.

[0039] FIG. 5(a) is a diagram showing the detailed layout of the pattern 1008 for pattern matching, and FIG. 5(b) is a diagram showing the detailed layout of the pattern 1017 for pattern matching. The distance 1101 corresponds to the number of pixels in the vertical direction of the pattern 1008 for pattern matching, and the distance 1102 corresponds to the number of pixels in the horizontal direction of the pattern 1008 for pattern matching. The distance 1103 corresponds to the number of pixels in the vertical direction of the pattern 1017 for pattern matching, and the distance 1104 corresponds to the number of pixels in the horizontal direction of the pattern 1017 for pattern matching.

[0040] In the present embodiment, the direction of the distance 1101 in the pattern 1008 for pattern matching is parallel to the conveyance direction 201, and the direction of the distance 1102 is parallel to the nozzle array direction 1001, and both correspond to 82 pixels in units of 1200 DPI. Also, the direction of the distance 1103 in the pattern 1017 for pattern matching is parallel to the conveyance direction 201, and the direction of the distance 1104 is parallel to the nozzle array direction 1001, and both correspond to 210 pixels in units of 1200 DPI. Note that the number of pixels constituting each pattern for pattern matching is not limited to the above, and other numbers of pixels may be used.

[0041] FIG. 6 is a diagram for explaining a test chart for calculating the displacement amounts between nozzle arrays, between recording element substrates, and between recording heads according to the present embodiment. In this figure, a test chart 1202 is recorded on a recording medium 1201 using roll paper by a recording head 102. Among the test charts 1202, test charts 1206 to 1213 are test charts for calculating the displacement amounts between nozzle arrays 1005, between recording element substrates 1002, and the inclination amount of the recording head 102. A test chart 1214 is a test chart for calculating the displacement amount between the recording heads 102. As shown in FIG. 4, the nozzle arrangement direction 1001 indicates the nozzle arrangement direction of the recording head 102.

[0042] As shown in FIG. 1, the inkjet recording apparatus 100 is provided with a plurality of recording heads 102. Each recording head 102 is assumed to correspond to eight colors of Pr (primer liquid), K (black), C (cyan), M (magenta), Y (yellow), O (orange), V (violet), and G (green) from the upstream side in the conveyance direction of the recording medium 1201. The color order of the recording head 102 may change, or the number of recording heads corresponding to other colors may increase or be replaced.

[0043] The scanner device 106 is arranged on the downstream side in the conveyance direction of the recording medium 1201 with respect to the recording head 102. The scanner device 106 reads the test chart 1202 recorded on the recording medium 1201 in order to detect the amount of misalignment of the recording head 102.

[0044] The types of head misalignment will be described. All of them are caused by, for example, the shaping error of the recording element substrate 1002 or the nozzles of the recording head 102, or the installation error of the recording head 102. The types of misalignment include the inter-column misalignment between nozzle rows 1005 for each recording element substrate 1002, the positional misalignment between recording element substrates 1002 for each recording head 102, the color misalignment between recording heads 102, etc. When there is such misalignment, the ink droplet ejection position deviates from the ideal position, resulting in a decrease in the quality of the recorded image. The head misalignment correction is a function that corrects the ink droplet ejection position by changing the ink ejection timing of the recording element substrate 1002 or the nozzles for ejection.

[0045] In this embodiment, for the misalignment in the direction orthogonal to the nozzle array direction 1001 (transport direction 201), the misalignment is corrected by changing the ejection timing of each recording element substrate 1002 constituting the recording head 102. For the misalignment in the nozzle array direction 1001, the misalignment is corrected by changing the ejection data. For the inclination of the recording head 102, the misalignment is corrected by combining both the change in ejection timing and the change in ejection data.

[0046] The test chart 1202 shown in FIG. 6 is a test chart for correcting the head position deviation of the recording head 102. The test charts 1206 to 1214 are test charts for eight heads, and each test chart is used to detect the amount of position deviation of each corresponding recording head 102. Using these test charts 1206 to 1214, the deviation amount between each nozzle row 1005 for each recording element substrate 1002, the deviation amount between the recording element substrates 1002 for each recording head 102, and the tilt amount of the recording head 102 are calculated. In the present embodiment, the test charts 1206 to 1213 are test charts corresponding to one of the recording heads 102 of O, G, V, K, C, M, Y, and Pr, respectively. The test chart of the recording head 102 included in the test chart 1202 may increase or decrease from the eight heads, or the order of the test charts may change. Therefore, the number of test charts may vary according to the number of recording heads 102 to be tested. Further, the test chart 1214 is a test chart for calculating the color deviation amount between the recording heads 102, and is recorded using all the recording heads 102. The test chart 1214 will be described later with reference to FIG. 7.

[0047] In the present embodiment, the test chart 1215 is an enlarged view of a part of the test chart 1209 corresponding to the ink color K. In the test chart 1215, the area represented in black is the area recorded with the corresponding ink. Further, the area represented in white is the base color of the recording medium 1201 and is an area not recorded with ink. Further, for each recording element substrate 1002 constituting the recording head 102, patches 1007 corresponding to the recording element substrate 1002 are linearly recorded so as to be arranged in parallel with the nozzle array direction 1001.

[0048] In the present embodiment, the test charts 1206 to 1208 and 1210 to 1212 corresponding to the ink colors O, G, V, C, M, and Y also have the same configuration as the test chart 1209.

[0049] In this embodiment, the test chart 1216 is an enlarged view of a part of the test chart 1211 corresponding to the primer liquid. The test chart 1216 is configured to be linearly recorded for each recording element substrate 1002 such that the patches 1016 shown in FIG. 4 are arranged in parallel with the nozzle array direction 1001.

[0050] Note that the correspondence between each test chart and the ink color may be changed depending on the type of the recording head 102, and the present invention is not limited to the example shown in FIG. 6.

[0051] FIG. 7 is a diagram showing the correspondence between the test chart 1214 for performing color misregistration correction calculation between the recording heads 102 and the recording element substrate 1002. A part of each color test chart is omitted. The test chart 1301 is a test chart 1214 for calculating the positional error between the recording heads 102. In the test chart 1301, the pattern matching patterns 1008 and 1017 are recorded by the recording heads 102 of each ink color shown in the layout 1302. In each recording head 102, one recording element substrate 1002 used for recording the test chart 1301 is selected. Here, the recording element substrate 1002 used for recording the test chart 1301 by each recording head 102 is the recording element substrate 1002 having the same position as the recording element substrate 1303 in the nozzle array direction 1001. That is, in any case of using any recording head 102, the pattern matching pattern 1008 is recorded using the recording element substrate 1002 having the same position as the recording element substrate 1303 in the nozzle array direction 1001. In the test chart 1301, the portions represented in black are the portions recorded in the corresponding ink color, and the portions represented in white indicate the paper white (substrate) portions of the recording medium 1201.

[0052] In this embodiment, for the colored inks of K, C, M, Y, O, G, and V, the pattern 1008 for pattern matching is used. As shown in layout 1302, with the recording head 102 corresponding to the ink color K as the reference head, the pattern 1008 for pattern matching is recorded at both ends, and the positional deviation of the recording head 102 corresponding to each ink other than the ink color K is calculated. In layout 1310, the amount of positional deviation of the recording head 102 corresponding to each of the inks C, M, and Y with the recording head 102 corresponding to the ink color K as the reference head can be calculated. In layout 1311, the amount of positional deviation of the recording head 102 corresponding to each of the inks O, G, and V with the recording head 102 corresponding to the ink color K as the reference can be calculated. By recording layouts 1310 and 1311 a plurality of times respectively, it becomes possible to calculate the positional deviation of the recording head 102 corresponding to each ink a plurality of times. By taking the average value of the results of calculating the positional deviation a plurality of times as the positional deviation of each recording head 102, the influence of the error of the positional deviation due to the recording timing is reduced, and a more accurate positional deviation can be obtained. The number of times of repeated recording of layouts 1310 and 1311 may be determined according to the required accuracy of calculating the positional deviation, and it may be once. The repetition of layouts 1310 and 1311 is omitted in the figure.

[0053] In this embodiment, for the positional deviation of the recording head 102 corresponding to the primer liquid, it is calculated using the pattern 1017 for pattern matching. As shown in layout 1302, with the recording head 102 corresponding to the ink color K as the reference head, it is recorded, and the positional deviation of the recording head 102 corresponding to the primer liquid is calculated. By recording layout 1312 a plurality of times, it becomes possible to calculate the positional deviation of the recording head 102 corresponding to the primer liquid a plurality of times in the same manner as the colored ink. The number of times of repeated recording of layout 1312 may be determined according to the required accuracy of calculating the positional deviation, and it may be once. The repetition of layout 1312 is omitted in the figure.

[0054] The pattern for pattern matching of the reference head uses the same pattern as the pattern for pattern matching of the recording head 102 for which deviation is to be calculated. Also, the pattern for pattern matching corresponding to a color is not limited to those shown in FIG. 5 and FIG. 7, and different patterns may be used.

[0055] The test chart 1301 used to calculate the color deviation between the recording heads 102 is recorded such that the recording timing on the recording medium 1201 exceeds the maximum deviation amount of the color deviation of the recording head 102. By shifting the recording timing of each recording head 102 in this way, the test charts do not overlap.

[0056] (Calculation of deviation amount between nozzle rows) FIG. 8 is a diagram showing a method for calculating the deviation amount between nozzle rows. As described above, in the present embodiment, 16 nozzle rows 1005 are arranged in one recording element substrate 1002. Here, the first nozzle row 1005 counted from the downstream side in the conveyance direction 201 is designated as R0, and the last nozzle row 1005 is designated as R15.

[0057] A method for calculating the deviation amount between the nozzle rows 1005 using the read image of the patch 1007 recorded according to the layout 1012 will be described. In the layout 1012, a rectangle enclosing a numerical value n (n ≧ 0) indicates the nozzle row 1005 on which the pattern for pattern matching 1008 recorded at that position is recorded. For example, the pattern for pattern matching 1008 corresponding to the rectangle 1405 indicates that it is recorded using the nozzle row 1005 of R0. Hereinafter, the pattern for pattern matching using the nozzle row 1005 of Rn and the rectangle indicating the recording position of the pattern are referred to as "Rn pattern".

[0058] As shown in FIG. 8(a), the layout 1012 is divided into four regions 1401 to 1404. In region 1401, the R0 patterns 1405 and 1406 are used as references. Similarly, in each of regions 1402 to 1404, the R0 patterns 1407 and 1408, the R0 patterns 1409 and 1410, and the R0 patterns 1411 and 1412 are used as references, respectively. In each of regions 1401 to 1404, based on two R0 patterns, the deviation amount from the patterns for pattern matching (R1 pattern to R15 pattern) using other nozzle arrays 1005 is calculated.

[0059] Using FIG. 8(b), as an example, a method for calculating the deviation amount between the nozzle array 1005 of R0 and the nozzle array 1005 of R9 will be described. The R0 pattern 1414 corresponds to the R0 pattern 1405 in region 1401, and the R0 pattern 1415 corresponds to the R0 pattern 1406 in region 1401, and each is a reference pattern for pattern matching. The R9 pattern 1416 is the R9 pattern recorded in region 1401. When each pattern for pattern matching is recorded by the nozzle array 1005 of R0 and the nozzle array 1005 of R9, if there is no deviation in the landing position of the ejected ink, the R9 pattern is recorded on the straight line connecting the R0 pattern 1414 and the R0 pattern 1415. The R9 pattern recorded at the ideal position without deviation in the landing position is indicated by the R9 pattern 1418. On the other hand, the actual recording position of the R9 pattern is indicated by the R9 pattern 1416.

[0060] The deviation amount between the R9 pattern 1416 and the R9 pattern 1418 becomes the position deviation amount of the nozzle array 1005 of R9 with respect to the nozzle array 1005 of R0. The horizontal component of the deviation amount is defined as the deviation amount 1417, and the vertical component is defined as the deviation amount 1419. The deviation amount 1419 is the length of the perpendicular line drawn from the R9 pattern 1416 with respect to the straight line connecting the R0 pattern 1414 and the R0 pattern 1415. Therefore, the deviation amount 1419 can be calculated from the positions of the R0 pattern 1414, the R0 pattern 1415, and the R9 pattern 1416. Similarly, the deviation amount 1417 can also be obtained from these positions.

[0061] By applying the method described above, the deviation amount of the R1 pattern to the R15 pattern can be calculated based on the R0 pattern, and the positional deviation amount of the nozzle arrays 1005 of R1 to R15 with respect to the nozzle array 1005 of R0 can be obtained.

[0062] (Calculation of deviation amount between recording element substrates) FIG. 9 is a diagram for explaining a method of calculating the deviation amount between the recording element substrates 1002. In the present embodiment, the first recording element substrate 1002 counted from the left side on the paper surface of FIG. 9 in the nozzle array direction 1001 is C0, and the last recording element substrate 1002 is C16. A method of calculating the deviation amount between the recording element substrates 1002 using the read image of the recorded patch 1007 according to the layout 1012 of the patch 1007 will be described with reference to the drawings.

[0063] The patches 1501 to 1503 shown in FIG. 9(a) schematically show the patches 1007 recorded according to the layout 1012 shown in FIG. 4 using three different recording element substrates 1002 in the same recording head 102. Depending on the size and conveyance error of the recording medium 1201, there may also be a recording element substrate 1002 on which no recording is performed on the recording medium 1201. Hereinafter, the patches for each recording element substrate 1002 recorded on the recording medium 1201 are referred to as "Cn patches" using Cn (n ≧ 0) indicating which of the plurality of recording element substrates 1002 for each recording head 102 it is.

[0064] Patch 1501 is the patch 1007 recorded by the recording element substrate 1002 of C1, which is one to the right from the leftmost among the plurality of patches 1007 recorded by one recording head 102. Depending on the size of the recording medium 1201 and the like, the recording element substrate 1002 for recording patch 1501 changes. In this embodiment, patch 1501 is taken as the C1 patch. Patch 1502 is the patch 1007 recorded by the recording element substrate 1002 of C15, which is one to the left from the rightmost among the patches 1007 recorded by the recording head 102 that recorded the C1 patch. In this embodiment, patch 1502 is taken as the C15 patch. Patch 1503 is the patch 1007 recorded by the recording element substrate 1002 that is the target for calculating the displacement amount between the recording element substrates 1002 among the patches 1007 recorded by the recording head 102 that recorded the C1 patch and the C15 patch. Here, as an example, the recording element substrate 1002 of C8 located in the center of the recording head 102 will be described.

[0065] The coordinate point 1507 shown in Fig. 9(b) is the midpoint of the line segment connecting two R0 patterns in the pattern matching pattern 1008 columns arranged in the nozzle array direction 1001 direction of patch 1501 (C1 patch), and is taken as the representative position of the C1 patch. Coordinate point 1508 is the midpoint of the line segment connecting two R0 patterns in the pattern matching pattern 1008 columns arranged in the nozzle array direction 1001 direction of patch 1502 (C15 patch), and this becomes the representative position of the C15 patch. The recording element substrates 1002 that recorded these C1 patch and C15 patch are the reference for calculating the displacement amount between the recording element substrates 1002. Coordinate point 1511 is the midpoint of the line segment connecting two R0 patterns in the pattern matching pattern 1008 columns arranged in the nozzle array direction 1001 direction of patch 1503 (C8 patch), and this becomes the representative position of the C8 patch. Here, the recording element substrate 1002 of C8 is the target for calculating the displacement amount between the recording element substrates 1002.

[0066] To calculate the displacement amount between the recording element substrates 1002, first consider the case where there is no landing position displacement when each patch 1007 is recorded at the representative positions of the C1, C8, and C15 patches respectively. In this case, on the straight line connecting the coordinate points 1507 and 1508, the representative position of the C8 patch when the landing position of the ejected ink can be recorded at the ideal position without displacement, that is, the midpoint of the line segment connecting the coordinate points 1507 and 1508 is indicated by the coordinate point 1512. On the other hand, the actual representative position calculated from the C8 patch on the read image is indicated by the coordinate point 1511. The displacement amount between the coordinate points 1511 and 1512 can be divided into a component parallel to the reference line connecting the coordinate points 1507 and 1508 and a component perpendicular to it. The component parallel to the reference line is the distance between the reference line and the actual representative position of the C8 patch, which is taken as the displacement amount 1514. The displacement amount 1514 is the length of the perpendicular line drawn from the coordinate point 1511 to the reference line. Therefore, the displacement amount 1514 can be obtained from the coordinate points 1507, 1508, and 1511. Also, the component perpendicular to the reference line is the distance between the line passing through the coordinate point 1511 and perpendicular to the reference line and the line passing through the coordinate point 1512 and perpendicular to the reference line, which is taken as the displacement amount 1513. Therefore, the displacement amount 1513 can be obtained from the coordinate points 1507, 1508, 1511, and 1512.

[0067] By applying the method shown above, with two recording element substrates 1002 as the reference, the displacement amounts of the other recording element substrates 1002 sandwiched between the reference recording element substrates 1002 can be obtained respectively. However, the calculation methods for the displacement amounts of the recording element substrates 1002 at the leftmost C0 and the rightmost C16, which are further on the end side than the two references (C1 and C15 in the example shown), are different.

[0068] For example, since the left end side of the two recording element substrates 1002 serving as a reference is C1 and the right end side is C15, the representative position of the C0 patch at the left end becomes the coordinate point 1511 to be adjusted, and the representative position of the C16 patch at the right end becomes the coordinate point 1511 to be adjusted. Similar to the others, the representative position of the C16 patch at the right end uses the midpoint of the line segment connecting two R0 patterns in the pattern matching pattern 1008 columns arranged in the nozzle array direction 1001. On the other hand, the representative position of the C0 patch at the left end uses the position of the pattern matching pattern corresponding to the rectangle 1011 recorded by the adjacent C1 recording element substrate 1002 on the right. This is because there is a possibility that the end recording element substrate 1002 can record only partially on the recording medium 1201 in the layout 1012.

[0069] Depending on the length of the recording medium 1201 in the nozzle row arrangement direction 1001, there may be recording element substrates 1002 of C0 or C16 outside the recording element substrate 1002 at the left end or the recording element substrate 1002 at the right end in the range where recording is performed. In such a case, since the recording element substrates 1002 of C0 or C16 cannot record on the recording medium 1201, it is impossible to detect the C0 patch or the C16 patch in its complete form. Therefore, the recording element substrate 1002 outside the left end side uses the deviation amount of one adjacent patch on the right as a correction value. Similarly, the recording element substrate 1002 outside the right end side uses the deviation amount of one adjacent patch on the left as a correction value.

[0070] (Calculation of the tilt amount of the recording head) Using FIG. 10, a method for calculating the tilt amount of the recording head 102 using the read image of the patch 1007 recorded according to the layout 1012 will be described. The calculation of the tilt amount of the recording head 102 uses the same patch 1007 as the patch for calculating the deviation amount between the recording element substrates 1002. Also, the tilt correction amount of the recording head 102 is the deviation amount from the average tilt of all the recording heads, and the tilt correction amount is calculated for each of all the recording heads.

[0071] The patches 1501 and 1502 shown in FIG. 10(a) are C1 patches and C15 patches recorded by the same recording head 102. The patches 1504 and 1505 shown in FIG. 10(b) are C1 patches and C15 patches recorded by the same recording head 102, although they are recorded by a recording head different from the recording head 102 that recorded the patches 1501 and 1502. From the patches 1504 and 1505 as well, coordinate points 1509 that are representative positions of the C1 patch and coordinate points 1510 that are representative positions of the C15 patch can be obtained, similar to the patches 1501 and 1502.

[0072] FIG. 10(c) is a diagram for explaining a method of calculating the tilt amount of the recording head 102. First, the tilt amount of each recording head 102 is calculated. The coordinate points 1507 and 1508 are representative positions of the C1 patch and the C15 patch recorded by the recording element substrate 1002 serving as a reference inside one of the left and right ends in the recording head 102A that recorded the patches 1501 and 1502. The angle 1516 indicates an angle (minor angle) formed by the line segment connecting the coordinate points 1507 and 1508 and an ideal line with no landing position deviation due to the tilt of the recording head 102A, and indicates the tilt amount of the recording head 102A.

[0073] Similarly, the tilt amount of the recording head 102B is calculated. The coordinate points 1509 and 1510 are representative positions of the C1 patch and the C15 patch recorded by the recording element substrate 1002 serving as the reference on the left and right end sides described above for the recording head 102B. The angle 1517 indicates an angle (minor angle) formed by the line segment connecting the coordinate points 1509 and 1510 and an ideal line with no landing position deviation due to the tilt of the recording head B, and indicates the tilt amount of the recording head 102B. Although not shown, the tilt amounts can be obtained in the same way for all the other recording heads 102.

[0074] Finally, the calculation amount of the tilt correction for each recording head 102 is calculated. The tilt correction amount based on the relative tilt amount of each recording head 102 can be calculated by the following formula. Here, the tilt amount of the recording head 102 is assumed to be indicated in terms of an angle.

[0075] (Tilt correction amount of each recording head 102) =(Average of the inclination of the full recording head 102) - (Inclination of each recording head 102) Assuming that the angle 1518 shown in Fig. 10(b) is the average of the inclination of the full recording head 102, for example, the inclination correction amount of the recording head 102A is the value obtained by subtracting the angle 1516 from the angle 1518.

[0076] By applying the method shown above, the inclination correction amount of each recording head 102 can be obtained with respect to the average of the inclination of the full recording head 102.

[0077] (Calculation of the deviation amount between recording heads) Fig. 11 is a diagram for explaining a method of calculating the deviation amount between the recording heads 102. In the present embodiment, the first recording head 102 counted from the upstream side in the conveyance direction 201 is defined as the recording head Pr using the primer liquid. The subsequent recording heads 102 are respectively referred to as the recording head K, the recording head C, the recording head M, the recording head Y, the recording head O, the recording head V, and the recording head G according to the color of the colored ink used. A method of calculating the deviation amount (hereinafter referred to as "color deviation") between the recording heads 102 using the read image of the test chart 1301 recorded using the recording heads 102 corresponding to a plurality of ink colors according to the layout 1302 will be described.

[0078] The test chart 1301 shown in Fig. 11(a) is a test chart 1214 used to calculate the color misregistration amount. The test chart 1301 is recorded using the recording element substrate 1303 at a predetermined position of the recording head 102 corresponding to a predetermined color shown in the layout 1302. In this embodiment, C8 is used as the recording element substrate 1303 at the predetermined position here. In this embodiment, the patterns 1601 to 1606 for pattern matching are patterns recorded on the recording element substrate 1303 of C8 of the recording head K which is the reference head (hereinafter referred to as the K pattern). The patterns with characters indicating other ink colors are each patterns recorded by the recording head 102 which is the object of calculation of the positional deviation between the recording heads 102. In this embodiment, these patterns are the patterns of C, M, Y, O, V, G, Pr (hereinafter referred to as the C pattern, etc.), but the number of ink colors may increase or decrease. In this embodiment, C, M, Y, O, V, G are recorded using the configuration of the pattern for pattern matching 1008 shown in Fig. 5. These reference K patterns 1601 to 1604 are also recorded using the configuration of the pattern for pattern matching 1008. On the other hand, the Pr pattern (hereinafter referred to as the Pr pattern) is recorded using the configuration of the pattern for pattern matching 1017 shown in Fig. 5 in this embodiment. These reference K patterns 1605 and 1606 are also recorded using the configuration of the pattern for pattern matching 1017.

[0079] In this embodiment, when calculating the deviation amount between the recording head K (reference head) and the recording heads 102 of other ink colors other than K, the same method is used for each recording head 102. Here, as an example, a method for calculating the deviation amount between the recording head K and the recording head V will be described. The K pattern 1620 shown in FIG. 11(b) corresponds to the K pattern 1603, and the K pattern 1621 corresponds to the pattern 1604. These are the patterns for pattern matching recorded at C8 of the reference recording head K. The V pattern 1622 corresponds to the V pattern 1617, and is the pattern for pattern matching recorded on the recording element substrate 1002 of C8 of the recording head V, and is the pattern for pattern matching recorded by the recording head 102 for which the deviation amount is to be calculated.

[0080] When there is no deviation in the landing position of the ejected ink, the V pattern recorded by the recording head V is recorded on the reference line connecting the K pattern 1620 and the K pattern 1621. The position of the V pattern in the ideal position where recording can be performed without deviation in the landing position of the ejected ink is indicated by the V pattern 1624. On the other hand, the position of the actual V pattern is indicated by the V pattern 1622.

[0081] In this embodiment, the deviation amount between the V pattern 1622 in the read image and the ideal V pattern 1624 is divided into a component perpendicular to the reference line and a component parallel to the reference line. Among the deviation amounts from the V patterns 1622 and 1624, the component perpendicular to the reference line is defined as the deviation amount 1625. This deviation amount 1625 is the length of the perpendicular line drawn from the V pattern 1622 to the reference line. Therefore, the deviation amount 1625 can be obtained from the positions of the K patterns 1620, K pattern 1621, and V pattern 1622. Among the deviation amounts from the V patterns 1622 and 1624, the component parallel to the reference line is defined as the deviation amount 1626. This deviation amount 1626 is the distance between the line passing through the V pattern 1622 and perpendicular to the reference line and the line passing through the V pattern 1624 and perpendicular to the reference line. Therefore, the deviation amount 1626 can be obtained from the positions of the K patterns 1620, K pattern 1621, V pattern 1622, and V pattern 1624. In the head position deviation correction in this embodiment, the correction amounts are calculated for both directions of the deviation amount 1625 and the deviation amount 1626.

[0082] By applying the method described above, the color deviation amounts between the recording head K as the reference head and the recording heads 102 of other ink colors than K can be obtained respectively.

[0083] (Mark detection process) FIG. 12 is a diagram for explaining the mark detection process corresponding to the recording element substrate 1002. In this embodiment, a process of detecting the detected marks for each patch 1007 corresponding to each recording element substrate 1002 from the read image of the test chart 1202 for calculating the deviation amount will be described. FIG. 12 shows the patches corresponding to each recording element substrate 1002, which correspond to the patch 1007 shown in FIG. 4. In this embodiment, there are two types of patches corresponding to each recording element substrate 1002, namely the patches 1007 and 1016 in FIG. 4, but the detection processes are all performed in the same manner. Also, the detection process for the test chart 1301 shown in FIG. 7 for calculating the positional error between the recording heads 102 is the same. Here, as an example, the patch 1007 shown in FIG. 4 will be used for explanation.

[0084] The mark detection process generally consists of three major steps. In the first step, the detection mark 1019 is detected. Based on the detected position of the detection mark 1019, the position of one patch 1007 on the recording element substrate 1002 is estimated. In the second step, based on the estimated position of the patch 1007 obtained in the first step, an alignment mark 1703 for estimating the position of the pattern 1008 for pattern matching is detected. The alignment mark 1703 is the same as the alignment mark 1020 in the patch 1007 shown in FIG. 4. Since this alignment mark 1703 is recorded near each pattern 1008 for pattern matching, the position of the corresponding pattern 1008 for pattern matching is estimated from the detected position of the alignment mark 1703. In the third step, based on the estimated position of the pattern 1008 for pattern matching in the second step, pattern position detection using pattern matching is performed.

[0085] The process of detecting the detection mark 1019 in the first step will be described. This process uses the luminance value of the channel with the highest density in the ink color of the recording head 102 of the pattern to be detected among the three RGB channels of the read image that can be read by the scanner device 106. For example, if the channel with the highest density is C (cyan), it is the R channel; if it is M (magenta), it is the G channel; if it is Y (yellow), it is the B channel. In the case of an ink color with a high density in all channels, such as K (black), any arbitrary channel can be specified and used.

[0086] 1705 is an enlarged view of a part of the detection mark 1019. The detection mark 1019 is detected based on the average density of a predetermined area of the read image. The detection mark detection area 1706 is the area where the average density is obtained. When the average density obtained in the detection mark detection area 1706 is equal to or higher than a predetermined density, that area is specified as the detection mark area, and its center position is set as the detection mark detection position 1707. The range of the detection mark detection area 1706 and the predetermined density used as the threshold value may be changed.

[0087] Subsequently, the left upper end position and the right upper end position of the detection mark 1019 are detected. 1708 is an enlarged view of the periphery of the left upper end of the detection mark 1019, and 1710 is an enlarged view of the periphery of the right upper end. The area with a predetermined concentration or higher is scanned from the detection mark detection position 1707, and the left upper end of the area with a predetermined concentration or higher is set as the detection mark left upper end position 1709. Similarly, the right upper end of the area with a predetermined concentration or higher is set as the detection mark right upper end position 1711. The detection range of the alignment mark 1703 is estimated by calculating the concentration center of gravity of a predetermined area starting from the position determined based on the detection mark left upper end position 1709. By detecting the detection mark 1019, the detection range of the alignment mark 1703 can be estimated. Regarding the detection process of the alignment mark 1703, it is the same as the detection process of the detection mark 1019. The area with a predetermined concentration or higher is scanned, and the position of the alignment mark 1703 is detected by calculating the concentration center of gravity for the area.

[0088] Subsequently, the position of the pattern 1008 for pattern matching is estimated. The area 1704 is an area indicating the left upper end position of the pattern 1008 for pattern matching. Also, the detection result of the detection mark 1019 is used to determine which recording head 102 and which recording element substrate 1002 this pattern 1008 for pattern matching corresponds to. After roughly estimating the position of the pattern 1008 for pattern matching by the above process, the position on the final read image is detected by performing a position detection process including pattern matching processing. The position of the pattern 1008 for pattern matching on the read image is the position for calculating the distances used in the calculation of various displacement amounts in the head position displacement correction. The various displacement amounts here include the manufacturing error between the nozzle rows 1005, the manufacturing error between the recording element substrates 1002, the inclination of the recording head 102, and the position displacement between the recording heads 102.

[0089] (Read images read by multiple sensors) FIG. 13 is an example of a read image of test chart 1202 obtained by two sensors 202A and 202B of scanner device 106 while transporting recording medium 1201 along transport direction 201. Read image 2001 and read image 2002 are simplified representations of what the test chart was read by sensor 202A, which is a CCD line sensor, and sensor 202B, respectively. When the width of recording medium 1201 extends over both the imaging regions of sensor 202A and sensor 202B, the read image of test chart 1202 consists of a read image obtained from sensor 202A and a read image obtained from sensor 202B.

[0090] Here, a method of obtaining a read image using scanner device 106 will be described. Light is incident on the recording surface of recording medium 1201 by a lamp (not shown) of scanner device 106 and is reflected, and this reflected light converges on sensor 202A or 202B through a lens. Each sensor 202 that has received this reflected light outputs an analog signal having an intensity corresponding to the amount of light, and the signal output from each sensor 202 is converted into a digital signal by scanner control unit 411. In this way, recording medium 1201 is first read line by line in the sensor column direction (the direction of arrow X shown in FIG. 13) by the CCD line sensor. This line-by-line reading is repeated while moving in the transport direction 201 of the recording medium that intersects (ideally, is perpendicular to) the sensor column direction X to read the entire test chart 1202. The digital signals obtained by reading are integrated to obtain a read image of the entire recorded test chart 1202. The read images of test chart 1202 obtained in such a manner are read images 2001 and 2002, and in the present embodiment, the amount of deviation from the ideal position of the ink landing position is calculated based on these multiple read images.

[0091] In FIG. 13, in each read image, each patch 1007 or 1016 for each recording element substrate 1002 that constitutes test charts 1206, 1207, and 1213 is represented by a rectangle enclosing a number n. That is, the rectangle enclosing the number n indicates that it is a patch recorded on the recording element substrate 1002 of Cn. For example, patch 2003 is the C8 patch of the recording head 102 for colored ink O. In the figure, the test chart 1202 of some recording heads 102 is omitted, and the overall image of the test chart 1202 varies depending on the number and color combination of the recording heads 102. Also, in each read image, there is a test chart 1214 for calculating the color misregistration amount between the recording heads 102 below the C8 patch.

[0092] In addition, since the sensors 202A and 202B are staggeredly arranged, they are installed at intervals along the conveyance direction 201. During scanning, due to sudden events such as paper flutter, peripheral airflow disturbance, and device vibration, the conveyance speed of the recording medium 1201 may temporarily vary. In such a case, the expansion and contraction of scan data occur along the conveyance direction 201. At this time, since the sensors 202A and 202B are separated in the conveyance direction, the ranges on the scan data where expansion and contraction occur are different between the scan data of the sensor 202A and the scan data of the sensor 202B. Therefore, even if the same test chart is scanned, the areas where the influence of expansion and contraction is different appear on the test chart 1202 in the read image obtained from the sensor 202A and the test chart 1202 in the read image obtained from the sensor 202B. In the example shown in FIG. 13, in the read image obtained from the sensor 202A, the influence of the conveyance speed variation that extends along the conveyance direction 201 appears on the test chart 1207. On the other hand, in the read image obtained from the sensor 202B, the influence of the conveyance speed variation that extends along the conveyance direction 201 appears on the test chart 1206. Here, to see the magnitude of the influence of the conveyance speed variation, for example, consider the case where the conveyance speed of the recording medium is 20 m / min, that is, 333.33 mm / sec, the reading resolution is 600×600 dpi, and the length of the patch 1007 in the conveyance direction is 10.50 mm. In this case, if the conveyance speed temporarily decreases by 5% to 316.66 mm / sec, the length of the patch 1007 read during this conveyance speed variation in the conveyance direction is 11.025 mm. The amount of change in the length of the patch 1007 before and after the conveyance speed variation is 11.025 - 10.50 = +0.525 (mm), which is +12 pixels / 600 dpi.

[0093] Since the sensors 202A and 202B are arranged in a staggered pattern, there are areas in the read images 2001 and 2002 that are read by both sensors. Hereinafter, this area will be referred to as the overlapping area, and the area other than this area will be referred to as the non-overlapping area. In the read image 2001, the area 2004 is the overlapping area, and in the read image 2002, the area 2005 is the overlapping area. The width of the overlapping area varies depending on the degree of overlap between the sensors, but in this embodiment, it needs to be a width that can include a pattern for calculating the expansion / contraction rate between the read images. The pattern for calculating the expansion / contraction rate between the read images is a patch recorded by one recording element substrate 1002 of one recording head 102, such as the pattern 2003 for example. The calculation of the expansion / contraction rate between the read images using the patches located in the overlapping area and the details of its utilization will be described later.

[0094] (Calculation of deviation amount based on test chart divided into multiple read images) Hereinafter, a method for calculating the deviation amounts between the nozzle rows 1005, between the recording element substrates 1002, and between the recording heads 102, and the tilt amount of the recording head 102 from the read images in this embodiment will be described.

[0095] The method for correcting the misalignment of the recording head 102 is as described above. However, when the test chart 1202 is obtained by being divided into a plurality of read images by being read separately by a plurality of sensors 202 as shown in FIG. 13, it is necessary to consider this point. In particular, when calculating the amount of misalignment between the recording element substrates 1002, for the reference line connecting the recording element substrates 1002 serving as references, the amount of misalignment with other recording element substrates 1002 sandwiched between these recording element substrates 1002 serving as references is obtained respectively. Since the recording element substrates 1002 one inside from both ends serve as references, in the test chart 1202 shown in FIG. 13, C1 and C15 serve as references. However, as shown in FIG. 13, when the test chart 1202 is divided into a plurality of read images, C1 is included only in the read image 2001, and C15 is included only in the read image 2002. That is, since each read image has only one patch corresponding to the recording element substrate 1002 serving as a reference, it is impossible to obtain the reference line connecting the recording element substrates 1002 serving as references with only one of the read images, and the amount of each misalignment and the amount of inclination cannot be calculated. For example, it is also possible to obtain the reference line connecting the recording element substrates 1002 serving as references by using the overlapping region and combining the two read images 2001 and 2002 into one image. However, the larger the read image, the larger the data amount of the read image itself, the higher the CPU processing load, and there is also a possibility that the processing speed other than the read image analysis decreases. In addition, in order to combine the two read images 2001 and 2002, processing for matching the inclination and color difference between the sensors 202A and 202B is also required. Therefore, it is more desirable to be able to calculate the amount of each misalignment and the amount of inclination without combining the read images 2001 and 2002. Therefore, in the present embodiment, the combination of the plurality of read images 2001 and 2002 obtained from the plurality of sensors 202A and 202B is not performed. The distance between the corresponding same patterns is corrected to be equal by multiplying the position information of the recording element substrate 1002 serving as a reference in the test chart 1202 on one read image by the corresponding expansion / contraction ratio. Then, a reference line is obtained based on the corrected position information and the position information of the uncorrected recording element substrate 1002 serving as a reference on the other read image corresponding thereto.Using the reference line obtained in this way, the displacement amounts between the nozzle arrays 1005, between the recording element substrates 1002, and between the recording heads 102, and the tilt amount of the recording head 102 are calculated.

[0096] FIG. 14 is a flowchart for calculating the displacement amount in this embodiment. Each step will be described.

[0097] In S3001, the scanner device 106 reads the test chart 1202 recorded on the recording medium 1201. The timing at which the scanner device 106 starts reading the test chart 1202 may be the timing when a predetermined time has elapsed since the start of recording the test chart 1202. Also, it may be the time when a predetermined amount of the recording medium has been conveyed after the end of recording the test chart 1202. The timing at which the reading ends is set to the timing when a predetermined number of lines have been read since the start of reading.

[0098] In S3002, the print controller 402 performs displacement amount calculation process 1 on the first read image 2001, which is the read image 2001 read by the sensor 202A in S3001. The displacement amount calculation process 1 is a process for calculating the displacement amount between the nozzle arrays 1005, the displacement amount between the recording heads 102, and the expansion / contraction ratio between the read images. Details of the process will be described later with reference to FIG. 15.

[0099] In S3003, the print controller 402 performs displacement amount calculation process 1 on the second read image 2002, which is the read image 2002 read by the sensor 202B in S3001. The displacement amount calculation process 1 is the same process as in S3002.

[0100] In S3004, the print controller 402 performs displacement amount calculation process 2 on the first read image 2001 and the second read image 2002. The displacement amount calculation process 2 is a process for calculating the displacement amount between the recording element substrates 1002 based on the reference line corrected based on the expansion / contraction ratio between the read images 2001 and 2002 and the tilt amount of the recording head 102. Details of the process will be described later with reference to FIG. 17.

[0101] As yet another embodiment, each step of the deviation amount calculation flow may be performed by the host device 500.

[0102] FIG. 15 is a diagram showing a processing flow of the deviation amount calculation process 1. Each step of the deviation amount calculation process 1 will be described with reference to this FIG. 15.

[0103] In S3101, the print controller 402 detects patches corresponding to each recording element substrate 1002 from the first and second read images of the test chart 1201 read in S3001. The process of detecting patches corresponding to each recording element substrate 1002 can be performed by the method described with reference to FIG. 12.

[0104] In S3102, the print controller 402 determines whether there is a test chart corresponding to the recording head 102 for which analysis of the deviation amount between the recording element substrates 1002 and the deviation amount between the nozzle rows 1005 has not been performed. The test charts corresponding to the recording head 102 are the test charts 1206 to 1213 shown in FIGS. 6 and 13. If there is a test chart corresponding to the recording head 102 for which analysis has not been performed, the process proceeds to S3103. If there is no patch corresponding to the recording head 102 for which analysis has not been performed, the process proceeds to S3108.

[0105] In S3103, the print controller 402 sequentially selects one test chart corresponding to the recording head 102 for which analysis of various deviation amounts has not been performed, for example, from the test chart 1206.

[0106] In S3104, the print controller 402 determines whether there is a patch 1007 or 1016 corresponding to the recording element substrate 1002 for which the deviation amount between nozzle rows 1005 has not been analyzed in the selected test chart. If there is a patch 1007 or 1016 corresponding to the recording element substrate 1002 for which the analysis has not been performed, the process proceeds to S3105; if there is no patch 1007 or 1016 corresponding to the recording element substrate 1002 for which the analysis has not been performed, the process proceeds to S3107. The patch corresponding to the recording element substrate 1002 to be analyzed is a patch 1007 or 1016 for each recording element substrate 1002 existing in the read images 2001 and 2002 read in S3101, and is bounded by a patch existing near the center of the overlapping region. If the patch serving as the boundary is a C8 patch, then for the read image 2001, the patches from C0 to C8, and for the read image 2002, the patches from C8 to C16 are the objects of analysis. The boundary patch 1007 or 1016 only needs to exist in the overlapping region, and for the read image 2001 and the read image 2002, the boundary can also be a C7 patch or a C9 patch.

[0107] In S3105, the print controller 402 selects one patch in order from C0, for example, if the read image is 2001, corresponding to the recording element substrate 1002 to be analyzed.

[0108] In S3106, the print controller 402 calculates the deviation amount between nozzle rows 1005 in the target recording element substrate 1002 using the read image including the patch 1007 or 1016 corresponding to the selected recording element substrate 1002 to be analyzed. The method for calculating the deviation amount between nozzle rows 1005 in this embodiment is performed by the method described with reference to FIG. 8. If the selected patch to be analyzed is patch 1007, the analysis is performed; if the selected patch to be analyzed is patch 1016, the analysis is skipped. Regarding the deviation amount between the C8 nozzle rows analyzed by both the read image 2001 and the read image 2002, the calculation result by either one of the read images is used.

[0109] In S3107, the print controller 402 estimates the position of the recording element substrate 1002 to be analyzed. The coordinates of the recording element substrate 1002 are the midpoint of the line segment connecting two pattern matching patterns 1008 recorded using R0 of each recording element substrate 1002, such as the coordinate point 1507 described with reference to FIGS. 9 and 10. For the position of the recording element substrate 1002 of C8 that is analyzed in both the read image 2001 and the read image 2002, the position in the coordinate system of the read image 2001 and the position in the coordinate system of the read image 2002 are estimated separately. The next step after S3107 is to return to S3103, and with the unanalyzed recording element substrate 1002 as the recording element substrate 1002 to be analyzed, the processes of S3106 and S3107 are performed on the patches corresponding to all the recording element substrates 1002 in the target recording head 102.

[0110] In S3108, the print controller 402 calculates the deviation amount between the recording heads 102 using a test chart 1214 for measuring the deviation amount between the recording heads 102 in the read images 2001 and 2002. The method for calculating the deviation amount between the recording heads 102 in the present embodiment is as described with reference to FIG. 11. Since the test chart 1214 is included in both the read image 2001 and the read image 2002, for the deviation amount between the recording heads 102, the calculation result using either one of the read images is utilized.

[0111] In S3109, the print controller 402 calculates the expansion / contraction rate of the patches 1007 and 1016 corresponding to the recording element substrate 1002 for each text chart 1202 between the read images. The method for calculating the expansion / contraction rate of the patches 1007 and 1016 corresponding to the recording element substrate 1002 between the read images will be described with reference to FIG. 16.

[0112] FIG. 16 is a diagram for explaining a procedure for calculating the expansion and contraction rates of patches 1007 and 1016 corresponding to the recording element substrate 1002 for each text chart 1202 among the read images. FIG. 16(a) is a detailed view of patch 2003 of the read image 2001 shown in FIG. 13, and FIG. 16(b) is a detailed view of patch 2003 of the read image 2002 shown in FIG. 13. Between patch 2003 of the read image 2001 and patch 2003 of the read image 2002, there is a difference in the expansion and contraction along the conveyance direction 201 because the affected areas of the conveyance speed variation are different. The difference is obtained as follows.

[0113] Patch 2003 is a patch configured with the layout 1012 shown in FIG. 4 used to calculate the deviation amount between the nozzle rows 1005, and is a patch existing in the overlapping region of the read images 2001 and 2002. In the read images 2001 and 2002, the distances 4001 and 4002 from the upper end of the R0 pattern 1405 recorded by the nozzle row 1005 of R0, which is the reference for calculating the deviation amount between the nozzle rows 1005, to the upper end of the R0 pattern 1411 are obtained. The distances 4001 and 4002 are respectively referred to as SR and ER. Then, the distance SR of the read image 2001 is divided by the distance ER in the read image 2002. As a result, as shown in FIG. 16(c), the expansion and contraction rate 4003 of the corresponding same text chart 1202 of the read image 2001 with respect to one of the text charts 1202 of the read image 2002 can be calculated. This expansion and contraction rate 4003 is referred to as K. The calculation formula for K is shown below.

[0114]

Equation

[0115] In the example shown in FIG. 16, SR < ER is assumed, but the reverse magnitude relationship may also occur. Also, in order to obtain the length along the conveyance direction 201 of the patch 2003 of the read images 2001 and 2002 obtained from the sensors 202A and 202B, two other points in the patch 2003 may be used. Here, a procedure for obtaining the expansion / contraction rate corresponding to one of the text charts 1202 between the read images obtained from each sensor using the patch 2003, which is the C8 patch of the recording head 102 for the colored ink O, is shown. However, patches recorded by the recording heads 102 of other ink colors may be used as long as they are included in the overlapping region of both read images 2001 and 2002 and the distance along the conveyance direction 201 can be calculated. Also, as long as the patches are included in the overlapping region of both read images 2001 and 2002 and correspond to the recording element substrate 1002 included in the same recording head 102, patches corresponding to different recording element substrates 1002 in the read images 2001 and 2002 may be used. Further, when the scanner device includes three or more sensors and three or more read images are obtained, the expansion / contraction rate is obtained for each pair of two read images by the method described above. At this time, the two read images to be used as a pair of read images are the read images obtained from two adjacent sensors in the scanner device 106.

[0116] FIG. 17 is a diagram showing the processing flow of the deviation amount calculation process 2. Each step of the deviation amount calculation process 2 will be described with reference to this FIG. 17.

[0117] In S3201, the print controller 402 determines whether there is a test chart corresponding to the recording head 102 for which the inclination amount calculation of the recording head 102 has not been performed in the first read image 2001 obtained from the sensor 202A. If there is a test chart corresponding to the recording head 102 for which the inclination amount calculation of the recording head 102 has not been performed, the process proceeds to S3202. If there is no test chart corresponding to the recording head 102 for which the inclination amount calculation of the recording head 102 has not been performed, the process proceeds to S3206. The processes from S3202 to S3205 are performed with the recording head 102 for which the inclination calculation of the recording head 102 has not been performed as the analysis target.

[0118] In S3202, the print controller 402 acquires the position information of each recording element substrate 1002 in the test chart corresponding to the recording head 102 for which the inclination amount calculation has not been performed. This position information of the recording element substrate 1002 is what was estimated in S3107 for the first read image 2001 obtained from the sensor 202A and the second read image 2002 obtained from the sensor 202B.

[0119] In S3203, the print controller 402 converts the representative positions of the patches 1007 corresponding to each recording element substrate 1002 in the first read image 2001 and the second read image 2002 into differential position information from the origin located in the overlapping region of each read image. Details of S3203 will be described later with reference to Fig. 18(a).

[0120] In S3204, the print controller 402 converts the differential position information of the second read image 2002 based on the differential position information of the second read image 2002 and the scaling factor K so that the scaling factor becomes 1. Here, converting so that the scaling factor becomes 1 means converting the distance between specific patterns in the second read image 2002 to be equal to the distance between the corresponding same specific patterns in the first read image 2001. Details of S3204 will be described later with reference to Fig. 18(b).

[0121] In S3205, the print controller 402 calculates the inclination of the reference line for calculating the deviation amount between the recording element substrates 1002 for the first read image 2001 and returns to S3201. Details of S3205 will be described later with reference to Fig. 19.

[0122] In S3206, the print controller 402 determines whether there is a test chart corresponding to the recording head 102 for which the amount of deviation between the recording element substrates 1002 has not been calculated. If there is a test chart corresponding to the recording head 102 for which the amount of deviation between the recording element substrates 1002 has not been calculated, the process proceeds to S3207. If there is no other test chart 1202 for the recording head 102 for which the amount of deviation between the recording element substrates 1002 has not been calculated, the series of processes ends.

[0123] In S3207, the print controller 402 selects one of the test charts corresponding to the recording head 102 for which the amount of deviation between the recording element substrates 1002 has not been calculated.

[0124] In S3208, the print controller 402 corrects the reference line so that the slope of the reference line corresponding to the test chart 1202 selected in S3207 is the same as the average of the slopes of all the recording heads 102. Details will be described later with reference to FIG. 20(a).

[0125] In S3209, the print controller 402 calculates the coordinates of each recording element substrate 1002 of the second read image 2002 in the coordinate system of the first read image 2001. Details will be described later with reference to FIG. 20(b).

[0126] In S3210, using the reference line and the coordinate information of each recording element substrate 1002 in the coordinate system of the first read image 2001 obtained in each step so far, the amount of deviation between all the recording element substrates 1002 is calculated in the coordinate system of the first read image.

[0127] Figures 18, 19, and 20 are diagrams for explaining each step of FIG. 17. In the figures, the horizontal axis of the image is the X-axis, and the vertical axis is the Y-axis. Here, only regions 1206A and 1206B, which are regions of the test chart 1206 in the first read image 2001 and the second read image 2002, are extracted. Hereinafter, the test chart 1206 will be described as an example, but it is also applicable to test charts 1207 to 1213. In the figures, in each read image, the patch 1007 for each recording element substrate 1002 constituting the test chart 1206 is represented by a rectangle enclosing the number n, indicating that it is a patch recorded on the recording element substrate Cn. Also, the positions of the patches 1007 of each recording element substrate 1002 represent the state where actual misalignment has occurred.

[0128] FIG. 18(a) is a diagram for explaining the procedure of calculating the differential position information of each recording element substrate 1002 in each read image in S3203. In the calculation of the differential position information, the representative position of one recording element substrate 1002 existing in the overlapping region of each read image is determined as the origin. Then, the distances from the origin to the representative positions of each recording element substrate 1002 are obtained for the X-axis and the Y-axis. In the first read image 2001, when the coordinate point 5001, which is the representative position of the C1 patch, is set as the origin, for example, since the representative position of the C8 patch is the coordinate point 5002, the differential position information of the C8 patch is such that the X-axis has a difference of 5003 and the Y-axis has a difference of 5004. In the second read image, when the coordinate point 5011, which is the representative position of the C8 patch, is set as the origin, for example, since the representative position of the C15 patch is the coordinate point 5012, the differential position information of the C15 patch is such that the X-axis has a difference of 5013 and the Y-axis has a difference of 5014. In the first read image 2001, the differential position information of C0 to C8 is saved, and in the second read image, the differential position information of C8 to C16 is saved. Here, the origin for calculating the differential position information is set as the representative position of the C0 patch in the first read image 2001 and the representative position of the C8 patch in the second read image. Since the origin when correcting the inclination of the reference line in S3208 is the representative position of the C0 patch, it is advisable to set the representative position of the C0 patch as the origin in the first read image 2001. In S3209, the representative positions of the patches 1007 corresponding to each recording element substrate 1002 of the second read image 2002 are calculated in the coordinate system on the first read image 2001. At that time, since the differential position information from the C8 patch is used with the C8 patch existing in the overlapping region as the boundary, the representative position of the C8 patch is set as the origin in the second read image 2002. In the present embodiment, the origin of each read image is set as the representative position of the C0 patch and the representative position of the C8 patch, but the origin can be set anywhere as long as the same calculation can be performed. Also, the patches 1007 corresponding to the recording element substrates 1002 for which the differential position information is saved in each read image are saved in each read image for the recording element substrates 1002 that exist only in each read image. For the patches 1007 corresponding to the recording element substrates 1002 existing in the overlapping region, only the patches 1007 serving as the boundary are saved in both read images, and the others may be saved in either one of the read images.Here, the boundary corresponds to the C8 patch in the above example.

[0129] FIG. 18(b) is a diagram for explaining a procedure of converting the differential position information of the second read image 2002 such that the magnification ratio becomes 1 based on the differential position information of the second read image 2002 and the corresponding magnification ratio K in S3204. Since the magnification ratio K corresponding to each of the text charts 1202 between the first read image 2001 and the second read image 2002 has been calculated in S3109, that value becomes the correction value of the second read image 2002. The distance between specific patterns in the second read image 2002 is converted to be equal to the distance between the corresponding same specific patterns in the first read image 2001. That is, the differential position information is corrected by multiplying by the magnification ratio K corresponding to the difference 5014. That is, correction is performed so that the distance SR between the R0 patterns in the C8 patch of the first read image 2001 shown in FIG. 16 is equal to the distance ER between the R0 patterns in the C8 patch of the second read image 2002. The differential position information of each recording element substrate 1002 of the second read image 2002 after correction can be calculated by multiplying them if there is a corresponding magnification ratio K with the differential position information before correction obtained in S3203.

[0130] The differential position information with the representative position of the C8 patch as the origin is corrected so that the distance between specific patterns in the second read image 2002 is equal to the distance between the corresponding same specific patterns in the first read image 2001. For example, in the case of the C15 patch, the representative position after correction becomes the coordinate point 5022. That is, the differential position information of the C15 patch after correction is converted such that the X-axis is the difference 5023 and the Y-axis is the difference 5024.

[0131] FIG. 19(a) and FIG. 19(b) are diagrams for explaining the procedure for obtaining a reference line in S3205. Here, the procedure for obtaining the reference line will be described in the coordinate system of the first read image 2001. First, it is necessary to calculate the coordinate points of the C15 patch required for obtaining the reference line in the coordinate system of the first read image 2001. In S3204, the distance between specific patterns in the first read image 2001 is made equal to the distance between the corresponding same specific patterns in the second read image 2002. Therefore, the coordinate points of the C15 patch can be calculated by adding the differential position information of the C15 patch in the second read image 2002 to the differential position information of the C8 patch in the first read image 2001. Specifically, the X coordinate of the C15 patch in the coordinate system of the first read image 2001 is the sum of the differential 5003 and the differential 5023. The Y coordinate of the C15 patch in the coordinate system of the first read image 2001 is the sum of the differential 5004 and the differential 5024. The coordinate point 5025 in FIG. 19(a) is the differential position information of the C15 patch in the coordinate system of the first read image 2001. As shown in FIG. 19(b), the line connecting the coordinate point 5001 of the C1 patch, which is the origin of the first read image 2001, and the obtained coordinate point 5025 of the C15 patch becomes the reference line of the corresponding recording head 102. Here, the procedure for obtaining the reference line in the coordinate system of the first read image 2001 has been described, but the reference line can be obtained in the same way in the coordinate system of the second read image 2002. In the coordinate system of the second read image 2002, it is necessary to obtain the coordinate points of the C0 patch for obtaining the reference line, which can be obtained using the differentials 5003 and 5004. Note that the reference line may be obtained in a third coordinate system that is neither the coordinate system of the first read image 2001 nor the coordinate system of the second read image, as long as the position information can be obtained in a common coordinate system.

[0132] FIG. 20(a) is a diagram for explaining the correction of the inclination of the reference line in S3208. In the present embodiment, during the process of calculating the displacement amount between the recording element substrates 1002, the inclination correction of each recording head 102 is performed. The inclination correction amount of each recording head 102 is obtained from the difference between the average of the inclinations of all the recording heads 102 and the inclination of each recording head 102 as described above. The inclination of each recording head 102 is obtained in S3205, and from this, the average of the inclinations of all the recording heads 102 is also obtained. The coordinate point 5027 shown in FIG. 20 is a coordinate point obtained by rotating the coordinate point 5001 by an angle 5026 which is the inclination correction amount of the corresponding recording head 102 with the coordinate point 5001 as the origin. Therefore, the line connecting the coordinate point 5001 and the coordinate point 5027 becomes the final reference line used for calculating the displacement amount between the recording element substrates 1002.

[0133] FIG. 20(b) is a diagram for explaining the procedure of calculating the coordinates of each recording element substrate 1002 of the second read image 2002 on the first read image 2001 in S3209. In order to calculate the displacement amount between the recording element substrates 1002 with respect to the obtained reference line, it is necessary to calculate the coordinate points of all the recording element substrates 1002 of the second read image 2002 in the coordinate system of the first read image 2001. For this purpose, the differential position information of each recording element substrate 1002 of the second read image 2002 recalculated in S3203 is used. This procedure is the same as the procedure of calculating the coordinate point of C15 in the coordinate system of the first read image 2001 in S3205. Using the reference line obtained in this way and the coordinate points which are the differential position information of each recording element substrate 1002, it becomes possible to calculate the displacement amount between all the recording element substrates 1002 in S3210.

[0134] As described above, according to the inkjet recording apparatus of the present invention, even when a test chart is divided into a plurality of read images by being read by a scanner device having a plurality of sensors, the displacement amount of the recording head can be accurately calculated.

[0135] In this embodiment, the number of sensors of the scanner device is two, but even when there are three or more sensors, if there is an overlapping area containing the test chart in the read images obtained by adjacent sensors, it is applicable.

[0136] Also, in this embodiment, processing necessary for calculating the displacement amount between the recording element substrates was performed, but if a reference line for obtaining a correction amount exists across a plurality of read images, it is also applicable to the calculation of other correction amounts. Also, although an inkjet recording device has been described as an example of the recording device so far, the method of applying the recording material is not limited to the inkjet method of discharging ink, and the technology of the present disclosure is applicable to a recording device using another method of applying the recording material.

[0137] <Other Embodiments> In the above embodiment, the inkjet recording device 100 has a plurality of recording heads 102, but it may have one recording head 102. The recording head 102 does not have to be a full-line head, and it may be a serial method in which ink is discharged from the recording head 102 while moving a carriage on which the recording head 102 is detachably mounted in the Y direction to form an ink image. The recording medium P may be a single-sheet paper, and in that case, it has a conveyance mechanism suitable for single-sheet paper.

[0138] (Other Examples) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiment to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

[0139] The present disclosure includes the following configurations and methods. [Configuration 1] An inkjet recording device having one or more recording means including a plurality of recording element substrates for applying a recording material, Reading control means for causing a reading device to read by dividing a test chart including a plurality of patches corresponding to each of the recording element substrates printed on a recording medium by the recording means; Calculating means for calculating a stretching ratio of patches corresponding to a recording element substrate included in the same recording means for a pair of reading images composed of two of the plurality of reading images based on the plurality of reading images obtained by causing the reading device to read the test chart printed on the recording medium; Adjusting means for adjusting the adhesion position of the recording material applied from the recording means based on the stretching ratio calculated by the calculating means and the position information of the patches in the plurality of reading images; A recording apparatus comprising the same. [Configuration 2] The patches corresponding to the recording element substrates included in the same recording means are included in an overlapping area where the same part of the test chart is read overlappingly in the pair of reading images. The recording apparatus according to Configuration 1, characterized in that. [Configuration 3] The patches corresponding to the recording element substrates included in the same recording means are patches corresponding to the same recording element substrate included in the same recording means. The recording apparatus according to Configuration 2, characterized in that. [Configuration 4] The adjusting means converts the position information of the patch in one of the pair of reading images so that the stretching ratio becomes 1, and combines the position information of the patches in the pair of reading images based on the position information of the patches in the overlapping area. The recording apparatus according to Configuration 2 or 3, characterized in that. [Configuration 5] The adjusting means calculates a deviation amount of the adhesion position of the recording material based on the combined position information of the patches, and adjusts the adhesion position of the recording material applied from the recording means based on the deviation amount. The recording apparatus according to Configuration 4, characterized in that. [Configuration 6] The deviation amount includes a deviation amount calculated based on a reference line connecting the positions of patches corresponding to two predetermined recording element substrates in the position information of the bonded patches. The recording apparatus according to Configuration 5, characterized in that. [Configuration 7] The reference line is a line connecting the positions of patches corresponding to two different recording element substrates included in the same recording means. The recording apparatus according to Configuration 6, characterized in that. [Configuration 8] The positions of the two patches constituting the reference line are represented by coordinate points in a common coordinate system. The recording apparatus according to Configuration 6 or 7, characterized in that. [Configuration 9] The positions of the two patches constituting the reference line are represented as differences indicating distances from the position of a predetermined patch in the overlapping region. The recording apparatus according to any one of Configurations 6 to 8, characterized in that. [Configuration 10] When the adjusting means has a plurality of the recording means, the adjusting means corrects the reference line so that the inclination of the reference line is the same as the average of the inclinations of the plurality of recording means. The recording apparatus according to any one of Configurations 6 to 9, characterized in that. [Configuration 11] The recording element substrate is a recording element substrate on which nozzles for discharging ink are arranged. The recording apparatus according to any one of Configurations 1 to 10, characterized in that. [Configuration 12] The pair of read images consists of two read images obtained by two adjacent optical sensors in the reading apparatus. The recording apparatus according to any one of Configurations 1 to 11, characterized in that. [Configuration 13] A recording method having one or a plurality of recording means including a plurality of recording element substrates for applying a recording material, A step of causing a reading device to read by dividing, with a plurality of optical sensors, a test chart including a plurality of patches corresponding to each of the recording element substrates printed on a recording medium by the recording means; Based on a plurality of read images obtained by causing the reading device to read the test chart printed on the recording medium, for a pair of read images consisting of two of the plurality of read images, a step of calculating a rate of expansion and contraction of a patch corresponding to a recording element substrate included in the same recording means; A step of adjusting an adhesion position of a recording material applied from the recording means based on the rate of expansion and contraction calculated in the calculating step and position information of the patch in the plurality of read images; A recording method, characterized by comprising the above steps. [Configuration 14] A program for causing a computer to execute each step of the recording method according to Configuration 13.

Claims

1. A recording apparatus having one or more recording means including a plurality of recording element substrates for applying a recording material, reading control means for causing a reading device to read by dividing, with a plurality of optical sensors, a test chart including a plurality of patches corresponding to each of the recording element substrates printed on a recording medium by the recording means; calculating means for calculating a stretching ratio of patches corresponding to recording element substrates included in the same recording means for a pair of reading images composed of two of the plurality of reading images based on the plurality of reading images obtained by causing the reading device to read the test chart printed on the recording medium; adjusting means for adjusting an adhesion position of the recording material applied from the recording means based on the stretching ratio calculated by the calculating means and the position information of the patches in the plurality of reading images. The recording apparatus characterized by comprising the above.

2. The patches corresponding to the recording element substrates included in the same recording means are included in an overlapping area where the same part of the test chart is read overlappingly in the pair of reading images. The recording apparatus according to claim 1, characterized by the above.

3. The patches corresponding to the recording element substrates included in the same recording means are patches corresponding to the same recording element substrate included in the same recording means. The recording apparatus according to claim 2, characterized by the above.

4. The adjusting means converts the position information of the patch in one of the pair of reading images so that the stretching ratio becomes 1, and combines the position information of the patches in the pair of reading images based on the position information of the patches in the overlapping area. The recording apparatus according to claim 2, characterized by the above.

5. The adjustment means calculates the deviation amount of the adhesion position of the recording material based on the position information of the combined patch, and adjusts the adhesion position of the recording material applied from the recording means based on the deviation amount. The recording apparatus according to claim 4, characterized in that.

6. The deviation amount includes a deviation amount calculated based on a reference line connecting the positions of the patches corresponding to two predetermined recording element substrates in the position information of the combined patch. The recording apparatus according to claim 5, characterized in that.

7. The reference line is a line connecting the positions of the patches corresponding to two different recording element substrates included in the same recording means. The recording apparatus according to claim 6, characterized in that.

8. The positions of the two patches constituting the reference line are represented by the coordinate points of a common coordinate system. The recording apparatus according to claim 6, characterized in that.

9. The positions of the two patches constituting the reference line are represented as differences indicating the distances from the position of a predetermined patch in the overlapping region. The recording apparatus according to claim 6, characterized in that.

10. When the adjustment means has a plurality of the recording means, the adjustment means corrects the reference line so that the inclination of the reference line becomes the same as the average of the inclinations of the plurality of recording means. The recording apparatus according to claim 6, characterized in that.

11. The recording element substrate is a recording element substrate on which nozzles for discharging ink are arranged. The recording apparatus according to claim 1, characterized in that.

12. The pair of read images consists of two read images obtained by two adjacent optical sensors in the reading device. The recording apparatus according to any one of claims 1 to 11, characterized in that.

13. A recording method having one or more recording means including a plurality of recording element substrates for applying a recording material, a step of dividing a test chart including a plurality of patches corresponding to each of the recording element substrates printed on a recording medium by the recording means with a plurality of optical sensors and causing a reading device to read the divided test chart; a step of calculating a rate of expansion and contraction of patches corresponding to recording element substrates included in the same recording means for a pair of reading images composed of two of the plurality of reading images based on the plurality of reading images obtained by causing the reading device to read the test chart printed on the recording medium; a step of adjusting an adhesion position of the recording material applied from the recording means based on the rate of expansion and contraction calculated in the calculating step and position information of the patches in the plurality of reading images; A recording method, characterized by comprising the above steps.

14. A program for causing a computer to execute each step of the recording method according to Claim 13.

Images