Recording device and recording method

Abstract

To provide an improvement for suppressing two-dimensional color unevenness caused by a plurality of inter-color distances.SOLUTION: A recording device includes a recording head including a first nozzle group that ejects a first ink and a second nozzle group that ejects a second ink having a color different from that of the first ink, a moving unit that relatively moves the recording head and a medium in a moving direction intersecting with a nozzle alignment direction, and a control unit. The recording head includes a first nozzle range in which a distance between the first nozzle group and the second nozzle group in the moving direction is a first distance and a second nozzle range in which the distance is a second distance greater than the first distance. When a secondary color is recorded by discharging the first and second inks in recording on the media using the nozzles belonging to the second nozzle range, the control unit records the secondary color by discharging the first and second inks with an ink volume corrected by a first correction value and a second correction value based on an offset value.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a recording apparatus and a recording method. [Background technology]

[0002] The recording head of an inkjet printer has nozzle groups for each ink, such as cyan (C), magenta (M), yellow (Y), and black (K), with nozzles aligned in the nozzle alignment direction. In the recording head, the nozzle groups for each ink are spaced apart in the direction of relative movement between the recording head and a medium, such as paper. In such a recording head, there may be multiple distances between nozzle groups of different colors in the direction of movement. The distance between nozzle groups of different colors in the direction of movement is referred to below as the "color distance."

[0003] Because there are multiple inter-color distances between the nozzle group of the first ink and the nozzle group of the second ink, unevenness in color may occur in the secondary color that is printed by overlapping the first ink and the second ink on the medium. As a technology for suppressing such color unevenness, a printing device has been disclosed that selects a color conversion lookup table (LUT) used in the color conversion process to lower the upper limit of the amount of ink that can be ejected per unit area for color combinations with multiple inter-color distances compared to color combinations with a constant inter-color distance (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-153953 Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional systems for selecting a color conversion LUT, if the input data format is a format after color conversion processing, that is, data in a format in which each pixel has a gradation value that represents the ink amount for each ink, it is difficult to suppress color unevenness in secondary colors caused by multiple inter-color distances. Therefore, there is room for improvement in suppressing color unevenness caused by multiple inter-color distances. [Means for solving the problem]

[0006] The recording device includes a recording head having a first nozzle group in which a plurality of nozzles that eject a first ink are aligned in a nozzle alignment direction, and a second nozzle group in which a plurality of nozzles that eject a second ink of a different color from the first ink are aligned in the nozzle alignment direction, a movement unit that moves the recording head and a medium relatively in a movement direction that intersects the nozzle alignment direction, and a control unit that controls the recording head and the movement unit, and the recording head has a first nozzle range that is a part of the first nozzle group and the second nozzle group, and a first distance between the first nozzle group and the second nozzle group in the movement direction, and a second nozzle range that is a part of the first nozzle group and the second nozzle group, and a first distance between the first nozzle group and the second nozzle group in the movement direction. and a second nozzle range, wherein the distance between the first nozzle group and the second nozzle group is a second distance longer than the first distance, and when recording on the medium using nozzles belonging to the second nozzle range, if a primary color is recorded on the medium by ejecting either the first ink or the second ink, the control unit records the primary color on the medium by ejecting either the first ink or the second ink with the ink amount corrected by a first correction value, and when a secondary color is recorded on the medium by ejecting the first ink and the second ink, the control unit records the secondary color on the medium by ejecting the first ink and the second ink with the ink amount corrected by a second correction value based on the first correction value and an offset value.

[0007] a moving unit that moves the print head and a medium relatively in a movement direction that intersects with the nozzle alignment direction; and a moving unit that moves the print head and a medium relatively in a movement direction that intersects with the nozzle alignment direction, wherein the print head has a first nozzle range that is a part of the first nozzle group and the second nozzle group, and a first distance between the first nozzle group and the second nozzle group in the movement direction; and a second nozzle range that is a longer second distance, and a recording process that controls the recording head and the moving unit to perform recording, wherein in the recording process, when recording on the medium using nozzles that belong to the second nozzle range, if a primary color is recorded on the medium by ejecting either the first ink or the second ink, the primary color is recorded on the medium by ejecting either the first ink or the second ink with the ink amount corrected by a first correction value, and when a secondary color is recorded on the medium by ejecting the first ink and the second ink, the secondary color is recorded on the medium by ejecting the first ink and the second ink with the ink amount corrected by a second correction value that is based on the first correction value and an offset value. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a simplified configuration of an apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a simplified diagram showing the relationship between the medium and the recording head from an overhead perspective. [Figure 3] FIG. 2 is an enlarged view illustrating a part of a recording head. [Figure 4] 10 is a flowchart showing an offset value setting process. [Figure 5] FIG. 10 is a diagram illustrating some of a plurality of secondary color test patterns recorded on a medium. [Figure 6] 10 is a flowchart showing a recording control process. [Figure 7] FIG. 10 is an enlarged view of a portion of a recording head according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the drawings are merely examples for explaining the present embodiment. Because the drawings are examples, the proportions, shapes, and shading may not be accurate, may not match each other, and some parts may be omitted.

[0010] 1. Brief description of the device configuration: 1 shows a simplified configuration of a recording device 10 according to this embodiment. The recording method of this embodiment is executed by the recording device 10. The recording device 10 includes a control unit 11, a display unit 13, an operation reception unit 14, a memory unit 15, a communication IF 16, a transport unit 17, a carriage 18, a recording head 19, etc. However, as will be described later, the carriage 18 is not necessary. IF stands for interface. The control unit 11 includes one or more ICs having a CPU 11a as a processor, a ROM 11b, a RAM 11c, etc., and other non-volatile memories, etc.

[0011] In the control unit 11, a processor, i.e., CPU 11a, executes calculations in accordance with a program 12 stored in ROM 11b or other memory, using RAM 11c as a work area, thereby realizing various functions such as an ink amount correction unit 12a, a print data generation unit 12b, and a print control unit 12c. The processor is not limited to a single CPU, and may be configured to perform processing using multiple CPUs or hardware circuits such as ASICs, or may be configured to perform processing in cooperation with a CPU and hardware circuits.

[0012] The display unit 13 is a means for displaying visual information and is configured, for example, by a liquid crystal display, an organic EL display, or the like. The display unit 13 may be configured to include a display and a drive circuit for driving the display. The operation reception unit 14 is a means for receiving input from a user and is realized, for example, by physical buttons, a touch panel, a mouse, a keyboard, or the like. Of course, the touch panel may be realized as one function of the display unit 13. The display unit 13 and the operation reception unit 14 may be collectively referred to as the operation panel of the recording device 10. The display unit 13 and the operation reception unit 14 may be part of the configuration of the recording device 10, or may be peripheral devices external to the recording device 10.

[0013] The storage unit 15 is, for example, a hard disk drive, a solid state drive, or other memory storage means. Part of the memory of the control unit 11 may be regarded as the storage unit 15. The storage unit 15 may be regarded as part of the control unit 11. The storage unit 15 stores various correction values ​​required in this embodiment.

[0014] The communication IF 16 is a collective term for one or more IFs that allow the recording device 10 to communicate with external devices via wired or wireless communication in accordance with a predetermined communication protocol, including a known communication standard. Examples of external devices include communication devices such as personal computers, servers, smartphones, and tablet terminals. As shown in FIG. 1, the recording device 10 may be connected to an external scanner 40 via the communication IF 16. The scanner 40 is a reading device that can optically read a document as a recording result.

[0015] The transport unit 17 is a means for transporting the medium 30 in a predetermined transport direction under the control of the control unit 11. The transport unit 17 includes, for example, rollers that rotate to transport the medium 30, and a motor as a power source for the rotation. The transport unit 17 may also be a mechanism that transports the medium 30 by placing the medium 30 on a belt or pallet that is driven by a motor. The medium 30 is, for example, paper, but may also be any medium that can be subjected to liquid recording, and may be made of materials other than paper, such as film or fabric.

[0016] The carriage 18 is a means for moving back and forth in a predetermined direction by the power of a carriage motor (not shown) under the control of the control unit 11. The carriage 18 carries a recording head 19. Therefore, in a configuration in which the recording device 10 has a carriage 18, the recording head 19 moves together with the carriage 18. On the other hand, in a configuration in which the recording device 10 does not have a carriage 18, the recording head 19 does not move. The recording head 19 is a means for performing recording by ejecting a liquid onto a medium 30 using an inkjet method under the control of the control unit 11. The liquid is mainly ink, but the recording head 19 can also eject liquids other than ink.

[0017] Recording device 10 may be realized by a single printer, or may be realized by a system having multiple devices connected to each other so that they can communicate with each other. For example, recording device 10 may be a system including an information processing device that functions as control unit 11, and a printer that performs recording under the control of the information processing device, including transport unit 17, carriage 18, and recording head 19. In this case, the information processing device can be understood as a recording control device, image processing device, etc.

[0018] 2. Recording head description: FIG. 2 shows a simplified top view of the relationship between the medium 30 and the recording head 19. In FIG. 2 and FIG. 3 described below, the carriage 18 is not present, and the recording head 19 is a line-type head that ejects ink while stationary on the transport path of the medium 30. The recording head 19 has multiple nozzles 20 for ejecting liquid such as ink. In FIG. 2, the multiple nozzles 20 of the recording head 19 are simply indicated by black dots. The recording head 19 can eject ink of multiple colors, such as C, M, Y, and K. The recording head 19 may also be called a liquid ejection head, a print head, a printing head, an inkjet head, or the like.

[0019] The direction D1 indicated by the arrow indicates the transport direction D1 of the medium 30 by the transport unit 17. Hereinafter, the upstream and downstream of the transport direction D1 will simply be referred to as upstream and downstream. The transport unit 17 is a means for realizing relative movement between the recording head 19 and the medium 30 in the transport direction D1, and therefore corresponds to the "moving unit," and the transport direction D1 corresponds to the "moving direction." The direction D2 perpendicular or nearly perpendicular to the transport direction D1 is the longitudinal direction D2 of the recording head 19. The length of the medium 30 in the longitudinal direction D2 is called the medium width. The line-type recording head 19 has a length sufficient to cover the medium width. The longitudinal direction D2 may also be called the width direction D2.

[0020] The control unit 11 controls the transport unit 17 to transport the medium 30 at a predetermined speed and the recording head 19 to eject ink onto the transported medium 30 based on the recording data representing the image. The ink droplets ejected by the nozzles 20 are called dots. As is known, the recording head 19 is provided with a drive element for each nozzle 20, and by controlling the application of a drive signal to the drive element of each nozzle 20 according to the recording data, each nozzle 20 ejects or does not eject a dot, thereby recording the image represented by the recording data on the medium 30. The ejection of a dot is also called dot-on, and the non-ejection of a dot is also called dot-off. Figure 2 shows a state in which an image 31 has been recorded on the area of ​​the medium 30 that has passed through the recording head 19.

[0021] FIG. 3 illustrates an enlarged portion of the recording head 19 shown in FIG. 2. In FIG. 3, each of the multiple white circles represents a nozzle 20. The recording head 19 is generally formed by arranging multiple nozzle chips 23. Each nozzle chip 23 has a common configuration. The nozzle chip 23 has nozzle rows 21C, 21M, 21Y, and 21K for each ink color. The nozzle row 21C is formed by arranging multiple nozzles 20 capable of ejecting C ink at predetermined intervals along the nozzle arrangement direction D3. Similarly, the nozzle row 21M is formed by arranging multiple nozzles 20 capable of ejecting M ink at predetermined intervals along the nozzle arrangement direction D3. The nozzle row 21Y is formed by arranging multiple nozzles 20 capable of ejecting Y ink at predetermined intervals along the nozzle arrangement direction D3. The nozzle row 21K is formed by arranging multiple nozzles 20 capable of ejecting K ink at predetermined intervals along the nozzle arrangement direction D3.

[0022] In the example of FIG. 3, the nozzle arrangement direction D3 diagonally intersects both the transport direction D1 and the width direction D2. The nozzle arrangement direction D3 can be considered the longitudinal direction of the nozzle chip 23. Furthermore, within the nozzle chip 23, nozzle rows 21K and 21Y are located on the left side, and nozzle rows 21M and 21C are located on the right side. In the explanation of FIGS. 2 and 3, left and right refer to left and right as viewed from downstream to upstream. Also, in the example of FIG. 3, within the nozzle chip 23, nozzle row 21K is located upstream of nozzle row 21Y, and nozzle row 21M is located upstream of nozzle row 21C. Furthermore, within the nozzle chip 23, a distance equivalent to several nozzles, i.e., a no-nozzle section 26 without nozzles 20, is secured between the pair of nozzle rows 21K and 21Y on the left side and the pair of nozzle rows 21M and 21C on the right side. The no-nozzle section 26 may not only be an area where no nozzles 20 exist as shown in FIG. 3, but also an area where unused nozzles 20 exist and where it can be considered that no nozzles 20 exist.

[0023] Focusing on each nozzle row 21K in this configuration in which multiple nozzle chips 23 are arranged, it can be said that within the print head 19, multiple nozzles 20 capable of ejecting K ink are arranged at regular or approximately regular intervals across the width direction D2. Therefore, these multiple nozzle rows 21K form a nozzle group 22K corresponding to the K ink. Similarly, focusing on each nozzle row 21Y in each nozzle chip 23, multiple nozzles 20 capable of ejecting Y ink are arranged across the width direction D2, and these multiple nozzle rows 21Y form a nozzle group 22Y corresponding to the Y ink. Focusing on each nozzle row 21M in each nozzle chip 23, multiple nozzles 20 capable of ejecting M ink are arranged across the width direction D2, and these multiple nozzle rows 21M form a nozzle group 22M corresponding to the M ink. Focusing on each nozzle row 21C of each nozzle chip 23, a plurality of nozzles 20 capable of ejecting C ink are aligned in the width direction D2, and these plurality of nozzle rows 21C form a nozzle group 22C corresponding to C ink.

[0024] For ease of explanation, the terms nozzle position and raster line will be used. A nozzle position is the position of each nozzle 20 in the width direction D2 and can be identified by integer numbers from #1 to #N along the width direction D2. In FIG. 2, the leftmost nozzle position in the width direction D2 is nozzle position #1, and the rightmost nozzle position is nozzle position #N. As can be seen from FIG. 3, in the recording head 19, nozzles 20 for K, Y, M, and C inks are located along the transport direction D1, corresponding to each nozzle position. A raster line is a row of pixels along the direction D1 and is also called a pixel row. The result of recording a pixel row on the medium 30 can also be called a raster line. One nozzle position corresponds to one raster line.

[0025] One of the multiple colors of ink ejected by the recording head 19 may be referred to as the “first ink” and the other as the “second ink.” Furthermore, among the nozzle groups 22C, 22M, 22Y, and 22K, the nozzle group corresponding to the first ink is referred to as the “first nozzle group,” and the nozzle group corresponding to the second ink is referred to as the “second nozzle group.” In this embodiment, the recording head 19 has a “first nozzle range” that is a portion of the first and second nozzle groups, where the distance between the first and second nozzle groups in the movement direction is a first distance, and a “second nozzle range” that is a portion of the first and second nozzle groups, where the distance between the first and second nozzle groups in the movement direction is a second distance that is longer than the first distance. In FIG. 3, the first nozzle range is indicated by reference numeral 24, and the second nozzle range is indicated by reference numeral 25.

[0026] As an example, focusing on three consecutive nozzle tips 231, 232, and 233 among the multiple nozzle tips 23 aligned along the width direction D2, the relationship between the distance between the first nozzle group and the second nozzle group in the movement direction (i.e., the inter-color distance) and the first nozzle range 24 and the second nozzle range 25 will be described. Adjacent nozzle tips 231 and 232 partially overlap in the width direction D2. Similarly, adjacent nozzle tips 232 and 233 partially overlap in the width direction D2. Furthermore, the right end of nozzle tip 231 and the left end of nozzle tip 233, which sandwich nozzle tip 232 between them, partially overlap in the width direction D2. The overlapping range of the right end of nozzle tip 231 and the left end of nozzle tip 233 in the width direction D2 is the second nozzle range 25, which corresponds to the no-nozzle section 26 of nozzle tip 232.

[0027] Here, assume that the first ink is Y ink and the second ink is C ink. Focusing on the color separation distance between the nozzle group 22Y and the nozzle group 22C in the conveyance direction D1, in the first nozzle range 24 where the nozzle row 21Y of the nozzle chip 232 and the nozzle row 21C of the nozzle chip 231 overlap in the width direction D2, the color separation distance = L1. On the other hand, in the second nozzle range 25 corresponding to the nozzleless portion 26 of the nozzle chip 232, where the nozzle row 21Y of the nozzle chip 233 and the nozzle row 21C of the nozzle chip 231 overlap in the width direction D2, the color separation distance = L2. As is clear from FIG. 3, L1 < L2. The color separation distance L1 corresponds to an example of the "first distance", and the color separation distance L2 corresponds to an example of the "second distance". Such a relationship between the first nozzle range 24, the second nozzle range 25, and the color separation distances L1, L2 is similarly repeated in the relationship between the plurality of nozzle chips 23 constituting the recording head 19.

[0028] According to the example of FIG. 3, in addition to the combination of Y ink and C ink, the combinations of Y ink and M ink, K ink and C ink, and K ink and M ink each correspond to a combination of a first ink and a second ink having a plurality of color separation distances. On the other hand, the combination of K ink and Y ink does not correspond to a combination of a first ink and a second ink having a plurality of color separation distances because the color separation distance between the nozzle group 22K and the nozzle group 22Y in the conveyance direction D1 is the same at any position in the width direction D2. For the same reason, the combination of M ink and C ink also does not correspond to a combination of a first ink and a second ink having a plurality of color separation distances.

[0029] According to the example in Figure 3, dots are ejected in the order of K, Y, M, and C inks by the recording head 19 at each nozzle position onto the medium 30 being transported from upstream to downstream. In other words, at each nozzle position, dots are ejected in the order of K, Y, M, and C inks to record a raster line. As can be seen from Figure 3, the first nozzle range 24 and the second nozzle range 25 are divisions along the width direction D2. Therefore, whether a given nozzle 20 belongs to the first nozzle range 24 or the second nozzle range 25 is predetermined by the nozzle position of that nozzle 20.

[0030] The arrangement of nozzle rows 21C, 21M, 21Y, and 21K within the nozzle chip 23 need only be common to each nozzle chip 23 and does not have to be as shown in FIG. 3. For example, the positions of nozzle row 21Y and nozzle row 21C may be interchanged within each nozzle chip 23. Therefore, depending on the arrangement of nozzle rows 21C, 21M, 21Y, and 21K within the nozzle chip 23, a combination of K ink and Y ink or a combination of M ink and C ink may correspond to a combination of a first ink and a second ink with a plurality of inter-color distances. Furthermore, the nozzle arrangement direction D3 does not have to be diagonal as shown in FIG. 3, but may be parallel to the width direction D2, i.e., perpendicular to the transport direction D1.

[0031] In the example of FIG. 3, when Y ink is ejected from nozzle group 22Y and C ink is ejected from nozzle group 22C to print a secondary color formed by overlapping Y ink and C ink on medium 30, color unevenness may occur. The secondary color formed by Y ink and C ink is a greenish color. In other words, due to differences in inter-color distances L1 and L2, the time difference between when a dot of Y ink is ejected onto medium 30 and when a dot of C ink is ejected differs between when nozzles 20 belonging to the first nozzle range 24 are used and when nozzles 20 belonging to the second nozzle range 25 are used. This difference in time difference affects ink drying and bleeding, resulting in differences in color density on medium 30.

[0032] 2 is an example of the result of printing a secondary color using such Y ink and C ink. Image 31 clearly shows the state in which a density difference occurs between the secondary color printed by each nozzle 20 belonging to the first nozzle range 24 and the secondary color printed by each nozzle 20 belonging to the second nozzle range 25. In this embodiment, the following processing is performed to suppress the density difference, or color unevenness, that occurs when printing such secondary colors.

[0033] 3. Explanation of correction values: When recording on the medium 30 using the nozzles 20 belonging to the second nozzle range 25, if the control unit 11 records a primary color on the medium 30 by ejecting either the first ink or the second ink, the control unit 11 records the primary color on the medium 30 by ejecting either the first ink or the second ink with the ink amount corrected by the "first correction value." On the other hand, when recording on the medium 30 using the nozzles 20 belonging to the second nozzle range 25, if the control unit 11 records a secondary color on the medium 30 by ejecting the first ink and the second ink, the control unit 11 records the secondary color on the medium 30 by ejecting the first ink and the second ink with the ink amount corrected by the "second correction value" which is determined by the first correction value and the "offset value."

[0034] First, the first correction value and the offset value will be described. As is well known, the first correction value is a correction value for correcting variations in the ejection characteristics of each nozzle 20, and is set in advance for each nozzle 20 of the recording head 19. Even when the exact same data is provided to each nozzle 20 corresponding to the same ink to cause ink to be ejected, the color value of the recording result on the medium 30 will be slightly different for each nozzle 20. The color value is, for example, brightness. Therefore, the first correction value is necessary to prevent variations between nozzles 20 from being visible in the recording result. The first correction value is basically set for all nozzles 20, regardless of the first nozzle range 24 or the second nozzle range 25.

[0035] For example, to set a first correction value for each nozzle 20 of nozzle group 22K, a predetermined test pattern using K ink is recorded on medium 30 by ejecting K ink from each nozzle 20 of nozzle group 22K and then measured using a scanner 40 or the like. Then, the first correction value for each nozzle 20 of nozzle group 22K is set according to the color value for each nozzle position measured from the test pattern. Generally speaking, according to the difference between the ideal reference value as the color value of the test pattern and the actual color value of the test pattern recorded by a certain nozzle 20, the correction value to be applied to the ink amount of K ink to cancel out the difference is set as the first correction value for that nozzle 20.

[0036] For example, for a nozzle 20 whose color value in the recorded result is a color darker than the reference value, the ink amount is greater than necessary, so a negative correction value is set to reduce the ink amount. Conversely, for a nozzle 20 whose color value in the recorded result is a color lighter than the reference value, the ink amount is less than necessary, so a positive correction value is set to increase the ink amount. In this embodiment, the first correction values ​​set for each nozzle 20 in each of the nozzle groups 22C, 22M, 22Y, and 22K are stored in the storage unit 15 or in a memory inside or outside the recording device 10 that is accessible by the control unit 11, and the control unit 11 can correct the ink amount using the first correction values.

[0037] The offset value is a value for correcting the first correction value to obtain the second correction value, and in this embodiment, the offset value is set only for each nozzle 20 that belongs to the second nozzle range 25. The set offset value is also used when recording a secondary color using the first ink and the second ink.

[0038] 4 is a flowchart showing the offset value setting process executed by the control unit 11 in accordance with the program 12. Also with reference to FIG. 4, it is assumed that the first ink is Y ink and the second ink is C ink, and a scene will be described in which offset values ​​related to secondary colors using Y ink and C ink are set.

[0039] In step S100, the control unit 11 controls the transport unit 17 and the recording head 19 to eject the first ink from each nozzle 20 of the first nozzle group and the second ink from each nozzle 20 of the second nozzle group, thereby recording multiple secondary color test patterns on the medium 30. Each of the multiple secondary color test patterns is recorded by applying ink amount correction using a first correction value to secondary color test pattern image data representing the secondary color test pattern, and further applying a different offset value to each secondary color test pattern for the ink amount to be recorded by the nozzles 20 belonging to the second nozzle range 25. The secondary color test pattern image data is stored in advance in the storage unit 15, for example.

[0040] FIG. 5 shows a simplified representation of a portion of each of the multiple secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 recorded on the medium 30 in step S100. These multiple secondary color test patterns are aligned along the transport direction D1. In FIG. 5, the ink amounts Yx and Cx, the first correction value H1, and the offset value used for recording each of the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 are clearly indicated on the medium 30. The ink amount Yx is the amount of Y ink specified for each pixel by the secondary color test pattern image data, and the ink amount Cx is the amount of C ink specified for each pixel by the secondary color test pattern image data. The ink amount is expressed using 256 gradations, for example, from 0 to 255. Furthermore, when the ink amount is normalized to 0 to 100%, it can also be considered as the ink recording rate per certain area.

[0041] The ink amounts Yx and Cx are common values ​​for each pixel of the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9, respectively, and represent a solid green image as the secondary color test pattern. As described above, the first correction value H1 is a value set for each nozzle 20, and varies from positive to negative for each nozzle 20. Therefore, Yx + H1 means that the ink amount Yx of the Y ink for each pixel constituting the secondary color test pattern is corrected using the first correction value H1 for each nozzle 20 of the nozzle group 22Y to which each pixel corresponds. The correspondence between pixels and the nozzles 20 used to print the pixels is known. Similarly, Cx + H1 means that the ink amount Cx of the C ink for each pixel constituting the secondary color test pattern is corrected using the first correction value H1 for each nozzle 20 of the nozzle group 22C to which each pixel corresponds.

[0042] In the example of FIG. 5, three offset values ​​are used: −1, 0, and +1. That is, the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 are printed on the medium 30 corresponding to all nine combinations: Yx+H1 plus any one of the offset values ​​−1, 0, or +1, and Cx+H1 plus any one of the offset values ​​−1, 0, or +1. For example, in the case of the secondary color test pattern TP7, the pixels printed by the nozzles 20 in the second nozzle range 25 among the pixels constituting the secondary color test pattern are printed on the medium 30 with the Y ink amount Yx corrected by the first correction value H1 as described above and an offset value of “+1” added, and the C ink amount Cx corrected by the first correction value H1 as described above and an offset value of “−1” added. Here, both the first correction value H1 and the offset value are correction values ​​that increase or decrease the gradation value as ink amount.

[0043] Of course, for each of the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9, the first correction value H1 is applied to pixels printed by the nozzles 20 in the first nozzle range 24, but no offset value is applied. Furthermore, the secondary color test pattern image data is converted into print data by correcting the Y and C ink amounts Yx and Cx for each pixel using the first correction value H1 and an offset value according to the pixel position, and then converting the data into dot-on or dot-off information for each Y and C ink through halftone processing. The halftone processing is performed using, for example, dithering or error diffusion. The print head 19 then ejects dots from each nozzle 20 in the nozzle groups 22Y and 22C in accordance with the print data, thereby printing the secondary color test pattern on the medium 30.

[0044] In step S110, the control unit 11 acquires the selection result of the secondary color test pattern. The user visually evaluates the multiple secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 recorded on the medium 30 in step S100. Then, the user selects the secondary color test pattern with the least color unevenness and inputs the selection result through an operation of the operation reception unit 14. The input selection result is acquired by the control unit 11.

[0045] Because the ink amounts Yx and Cx of the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 are all printed after being corrected using the first correction value H1, irregularities between nozzle positions resulting from variations in the ejection characteristics of each nozzle 20 are eliminated. However, color irregularities due to differences in the inter-color distance between the first nozzle range 24 and the second nozzle range 25, as described above, may occur in the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9. In the example of Figure 5, color irregularities due to differences in the inter-color distance occur in the secondary color test patterns TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9, but not in the secondary color test pattern TP1.

[0046] Therefore, the user can select the secondary color test pattern TP1 and input it to the control unit 11. In other words, in the example of Fig. 5, the offset value "-1" for the Y ink and the offset value "-1" for the C ink are ultimately appropriate offset values ​​for eliminating color unevenness of secondary colors according to differences in inter-color distance.

[0047] The control unit 11 may obtain the selection result of the secondary color test pattern in response to input from the scanner 40, rather than input from the user. That is, the user causes the scanner 40 to read the medium 30 on which multiple secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9 are recorded in step S100. Then, the control unit 11 inputs read image data from the scanner 40 as the reading results of the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9. The control unit 11 may analyze this read image data and select the secondary color test pattern with the least color unevenness from among the secondary color test patterns TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, and TP9.

[0048] In step 120, the control unit 11 stores the offset value applied in step S100 when recording the secondary color test pattern related to the selection obtained in step S110 in the memory unit 15 or the like in association with the ink color and secondary color to be applied, and ends the flowchart in Fig. 4. Although details are omitted, the first correction value for each nozzle 20 may naturally be a value that is finely set for each gradation value of the ink amount to be corrected.

[0049] 4 for each of the ink combinations having a plurality of inter-color distances in the print head 19, in addition to the secondary color formed by Y ink and C ink, and can store appropriate offset values ​​for printing the secondary color using the nozzles 20 in the second nozzle range 25. Furthermore, the offset values ​​used when printing the plurality of secondary color test patterns in step S100 do not have to be limited to the above-mentioned numerical values ​​of -1, 0, and +1. For example, the plurality of secondary color test patterns may be printed using offset values ​​that vary within a numerical range from -3 to +3.

[0050] 4. Recording control process: 6 is a flowchart showing the recording control process executed by the control unit 11 in accordance with the program 12. This flowchart includes a "recording step" for controlling the recording head 19 and the moving unit to perform recording. In step S200, the print data generation unit 12b of the control unit 11 acquires "ink volume image data" that represents the image to be printed. The ink volume image data is image data in which each pixel has the amount of ink for each ink that can be ejected by the print head 19. For example, the print data generation unit 12b acquires the ink volume image data specified through a user operation on the operation reception unit 14 from an image data storage location such as the storage unit 15 or a memory inside or outside the printing device 10. Alternatively, the print data generation unit 12b receives and acquires the ink volume image data sent from an external device via the communication IF 16.

[0051] If the format of the image data at the time of acquisition is not ink volume image data, the record data generation unit 12b simply converts the image data into ink volume image data. For example, if the acquired image data is RGB image data having red (R), green (G), and blue (B) gradation values ​​for each pixel, the record data generation unit 12b converts each RGB gradation value for each pixel of the image data into each CMYK gradation value by referencing a color conversion LUT that predefines the conversion relationship between RGB and CMYK. In this way, in either case, in step S200, the record data generation unit 12b acquires ink volume image data.

[0052] In steps S210 to S260, the ink amount correction unit 12a corrects the ink amount image data acquired in step S200. Steps S210 to S260 may be called the ink amount correction process. In step S210, the ink amount correction unit 12a selects one of the pixels that make up the ink amount image data as the correction target. The pixel selected in step S210 is called the "target pixel."

[0053] In step S220, the ink amount correction unit 12a determines whether the target pixel is a pixel that corresponds to the second nozzle range 25. Pixels that correspond to the second nozzle range 25 are pixels at positions that are printed by nozzles 20 that belong to the second nozzle range 25. Pixels that do not correspond to the second nozzle range 25 are pixels at positions that are printed by nozzles 20 that belong to the first nozzle range 24. If the target pixel is a pixel that corresponds to the second nozzle range 25, the ink amount correction unit 12a proceeds from "Yes" in step S220 to step S230; on the other hand, if the target pixel is a pixel that does not correspond to the second nozzle range 25, the ink amount correction unit 12a proceeds from "No" in step S220 to step S250.

[0054] In step S230, the ink amount correction unit 12a determines whether the target pixel has a secondary color made up of a first ink and a second ink. Here, the first ink and the second ink refer to combinations of inks that are related by a plurality of inter-color distances in the recording head 19. Referring to the example in Figure 3, as described above, the Y and C ink combination, the Y and M ink combination, the K and C ink combination, and the K and M ink combination each correspond to combinations of a first ink and a second ink, while the K and Y ink combination and the C and M ink combination do not correspond to combinations of a first ink and a second ink.

[0055] "Having a secondary color made up of the first ink and the second ink" means that the first ink and the second ink each have a gradation value greater than 0. For example, a target pixel with ink amounts (C,M,Y,K)=(50,0,50,0) can be said to have a secondary color made up of the first ink and the second ink in that neither the C nor the Y gradation value is 0. Also, a target pixel with ink amounts (C,M,Y,K)=(100,40,120,0) can be said to have a secondary color made up of the first ink and the second ink in that neither the C nor the Y gradation value is 0, and can also be said to have a secondary color made up of the first ink and the second ink in that neither the M nor the Y gradation value is 0.

[0056] If the target pixel has a gradation value of 0 for all CMYK colors, or if only one of the CMYK colors has a gradation value greater than 0, then it cannot be said to have a secondary color made up of the first and second inks. Also, if the target pixel has neither C nor M gradation values ​​of 0, such as (C,M,Y,K)=(50,20,0,0), then according to the example in Figure 3, the C and M inks do not fall under the combination of the first and second inks, and therefore it cannot be said to have a secondary color made up of the first and second inks.

[0057] If the target pixel has a secondary color formed by the first ink and the second ink, the ink amount correction unit 12a determines "Yes" in step S230 and proceeds to step S240. On the other hand, if the target pixel does not have a secondary color formed by the first ink and the second ink, the ink amount correction unit 12a determines "No" in step S230 and proceeds to step S250. The case in which the target pixel has a gradation value greater than 0 for only one of the CMYK colors and therefore determines "No" in step S230 and proceeds to step S250 corresponds to a case in which the primary color is recorded by ejecting either the first ink or the second ink when recording on the medium 30 using the nozzles 20 belonging to the second nozzle range 25. In this case, as described below, the primary color is recorded on the medium 30 by ejecting either the first ink or the second ink, the ink amount of which has been corrected using the first correction value. The case where the judgment in step S230 is "Yes" and the process proceeds to step S240 corresponds to the case where a secondary color is recorded by ejecting the first ink and the second ink when recording on the medium 30 using the nozzles 20 belonging to the second nozzle range 25.

[0058] In step S240, the ink amount correction unit 12a corrects the ink amount of the target pixel using a second correction value. The second correction value is a correction value obtained by applying an offset value to the first correction value. Correction using the second correction value is synonymous with correction using the first correction value and an offset value. In other words, the CMYK tone values ​​of the target pixel, excluding 0, are corrected using the first correction value set for the CMYK nozzles 20 at the positions used to print the target pixel and the offset values ​​already set in the offset value setting process described above.

[0059] As a specific example, assume that the ink amount for the target pixel is (C,M,Y,K)=(50,0,50,0). Also assume that the first correction value for the nozzle 20 for C ink corresponding to the position of the target pixel is -2, the first correction value for the nozzle 20 for Y ink corresponding to the position of the target pixel is +3, the offset value for C ink among the offset values ​​for the secondary color formed by C ink and Y ink is -1, and the offset value for Y ink among the offset values ​​for the secondary color formed by C ink and Y ink is -1. In this case, the ink amount correction unit 12a adds the first correction value of -2 and the offset value of -1 to C=50 for the target pixel. Furthermore, it adds the first correction value of +3 and the offset value of -1 to Y=50 for the target pixel. As a result, the ink amount for the target pixel is corrected to (C,M,Y,K)=(47,0,52,0).

[0060] Depending on the ink amount of the target pixel, multiple offset values ​​may be applicable to the ink amount of one color. As a specific example, assume that the ink amounts of the target pixel are (C, M, Y, K) = (50, 80, 50, 0). As described above, assume that the first correction value of the nozzle 20 for C ink corresponding to the position of the target pixel is -2, the first correction value of the nozzle 20 for Y ink corresponding to the position of the target pixel is +3, the offset value of C ink among the offset values ​​for the secondary color formed by C ink and Y ink is -1, and the offset value of Y ink among the offset values ​​for the secondary color formed by C ink and Y ink is -1. Furthermore, assume that the first correction value of the nozzle 20 for M ink corresponding to the position of the target pixel is -3, the offset value of M ink among the offset values ​​for the secondary color formed by M ink and Y ink is +1, and the offset value of Y ink among the offset values ​​for the secondary color formed by M ink and Y ink is -1. In this case, the ink amount correction unit 12a adds the first correction value of -2 and the offset value of -1 to C = 50 for the target pixel, correcting it to C = 47. Furthermore, the first correction value of −3 and the offset value of +1 are added to M=80 of the target pixel to correct it to M=78.

[0061] As described above, when the ink amounts of the target pixel are (C, M, Y, K) = (50, 80, 50, 0), there are multiple applicable offset values ​​for Y ink, such as an offset value of -1 for the secondary color with C ink and an offset value of -1 for the secondary color with M ink. The ink amount correction unit 12a may simply add these applicable offset values, correcting Y=51 by adding the first correction value of +3 and the offset value of -2 to Y=50 of the target pixel. Alternatively, in consideration of the possibility that applying multiple offset values ​​simultaneously may result in excessive correction, the ink amount correction unit 12a may add these applicable offset values ​​with a predetermined weighting and add them to the first correction value. For example, Y=50 of the target pixel may be corrected to Y=52 by adding the first correction value of +3 and the average value of the multiple offset values ​​of -1.

[0062] Meanwhile, in step S250, the ink amount correction unit 12a corrects the ink amount of the target pixel using the first correction value. That is, the gradation values ​​of each of the CMYK colors of the target pixel, excluding 0, are corrected using the first correction value set for the nozzles 20 of each of the CMYK colors at the positions used to print the target pixel.

[0063] After step S240 or step S250, in step S260, the ink amount correction unit 12a determines whether all pixels that make up the ink amount image data have been selected as target pixels. If there are any pixels that have not been selected as target pixels, the process returns to step S210 from "No" in step S260, and a new pixel is selected as the target pixel. On the other hand, if all pixels that make up the ink amount image data have been selected as target pixels, the process proceeds to step S270 from "Yes" in step S260.

[0064] In step S270, the print data generation unit 12b performs halftone processing on the corrected ink amount image data, and generates print data having dot-on or dot-off information for each pixel and each ink.

[0065] In step S280, the recording control unit 12c executes a process for outputting the recording data. That is, the recording control unit 12c controls the transport unit 17 to start transporting the medium 30 and transfers the recording data to the recording head 19. As a result, dots of each ink are ejected from each nozzle 20 onto the medium 30 in accordance with the recording data, and an image represented by the recording data is recorded on the medium 30. In this recording result, the first correction value has suppressed color unevenness caused by variations in the ejection characteristics of each nozzle 20. In addition, the offset value has suppressed color unevenness caused by multiple inter-color distances between the nozzle group for the first ink and the nozzle group for the second ink related to secondary color recording, as in the secondary color test pattern TP1 in FIG. 5, for example.

[0066] The offset value may be a value used by adding it to the first correction value, such as "+1" or "-1" as explained above, or it may be a coefficient that represents a ratio, such as 1.5 or 0.75. In other words, the offset value as a ratio may be multiplied by the first correction value to obtain a second correction value, and the ink amount may be corrected using the second correction value.

[0067] 5. Summary: As described above, according to this embodiment, the recording device 10 includes a recording head 19 having a first nozzle group in which a plurality of nozzles 20 that eject a first ink are aligned in the nozzle alignment direction D3, and a second nozzle group in which a plurality of nozzles 20 that eject a second ink of a different color from the first ink are aligned in the nozzle alignment direction D3, a movement unit that moves the recording head 19 and a medium 30 relatively in a movement direction that intersects the nozzle alignment direction D3, and a control unit 11 that controls the recording head 19 and the movement unit. The recording head 19 has a first nozzle range 24 that is part of the first nozzle group and the second nozzle group, and in which the distance between the first nozzle group and the second nozzle group in the movement direction is a first distance, and a second nozzle range 25 that is part of the first nozzle group and the second nozzle group, and in which the distance between the first nozzle group and the second nozzle group in the movement direction is a second distance that is longer than the first distance. Then, when recording on the medium 30 using the nozzles 20 belonging to the second nozzle range 25, if the control unit 11 records a primary color on the medium 30 by ejecting either the first ink or the second ink, the control unit 11 records the primary color on the medium 30 by ejecting either the first ink or the second ink with the ink amount corrected by the first correction value, and if the control unit 11 records a secondary color on the medium 30 by ejecting the first ink and the second ink, the control unit 11 records the secondary color on the medium 30 by ejecting the first ink and the second ink with the ink amount corrected by the second correction value based on the first correction value and the offset value.

[0068] According to the above configuration, when recording a secondary color using the first ink and the second ink on the medium 30 using the nozzles 20 belonging to the second nozzle range 25, the control unit 11 corrects the ink amount using the second correction value based on the first correction value and the offset value. This makes it possible to suppress color unevenness in the secondary color, such as that shown in image 31 in FIG. 2, which occurs in the recording result due to the difference between the first distance and the second distance, and to provide good image quality. Furthermore, according to this embodiment, because the ink amount is corrected using the second correction value, color unevenness in the secondary color caused by multiple inter-color distances can be suppressed even if the input data format is ink amount image data.

[0069] This embodiment discloses inventions in various categories, such as not only devices and systems, but also methods executed by devices and systems, and programs 12 that cause a processor to execute the methods. For example, a recording method using a recording device 10 including a recording head 19 having a first nozzle group in which a plurality of nozzles 20 that eject a first ink are aligned in the nozzle alignment direction D3, and a second nozzle group in which a plurality of nozzles 20 that eject a second ink of a different color from the first ink are aligned in the nozzle alignment direction D3, and a movement unit that relatively moves the recording head 19 and a medium 30 in a movement direction intersecting the nozzle alignment direction D3, includes a recording step of controlling the recording head 19 and the movement unit to perform recording. In the recording step, when recording on the medium 30 using nozzles 20 belonging to a second nozzle range, if a primary color is recorded on the medium 30 by ejecting either the first ink or the second ink, the primary color is recorded on the medium 30 by ejecting either the first ink or the second ink with the ink amount corrected by a first correction value, and if a secondary color is recorded on the medium 30 by ejecting both the first ink and the second ink, the secondary color is recorded on the medium 30 by ejecting the first ink and the second ink with the ink amount corrected by a second correction value determined by the first correction value and an offset value.

[0070] 6. Variations: Several modifications included in this embodiment will be described. Combinations of the modifications are also included in the scope of disclosure of this embodiment. Regarding the modifications, descriptions common to the previous embodiments will be omitted as appropriate.

[0071] First variant: FIG. 7 shows an enlarged portion of a recording head 19 according to a first modified example. The viewing angle of FIG. 7 is the same as that of FIG. 3. In the first modified example, the multiple nozzle chips 23 aligned along the width direction D2 are collectively referred to as a "nozzle group unit." The recording head 19 has multiple nozzle group units. FIG. 7 shows a nozzle group unit 19A as a "first nozzle group unit" and a nozzle group unit 19B as a "second nozzle group unit." The multiple nozzle group units, including the nozzle group units 19A and 19B, are arranged along the transport direction D1 and share a common configuration. Each of the multiple nozzle group units can be considered to have substantially the same configuration as the recording head 19 described in FIG. 3. Therefore, the division of the first nozzle range 24 and the second nozzle range 25 in the width direction D2 is also common to the multiple nozzle group units.

[0072] 3, the print head 19 in Fig. 7 has the nozzle row 21Y and the nozzle row 21C swapped in position within each nozzle chip 23. That is, within the nozzle chip 23, the nozzle row 21C is located on the left side and downstream of the nozzle row 21K, and the nozzle row 21Y is located on the right side and downstream of the nozzle row 21M. Therefore, in the first modified example, the combination of K ink and M ink, the combination of K ink and Y ink, the combination of C ink and M ink, and the combination of C ink and Y ink each correspond to the first ink and the second ink having a plurality of inter-color distances.

[0073] It is possible to complete recording using the four colors CMYK on the medium 30 using only one nozzle group unit, or it is also possible to use multiple nozzle group units to complete recording using the four colors CMYK on the medium 30. Therefore, assuming a case where a secondary color is recorded using C ink and Y ink, for example, recording can be performed using nozzle group 22C and nozzle group 22Y in nozzle group unit 19A, or recording can be performed using nozzle group 22C of nozzle group unit 19A and nozzle group 22Y of nozzle group unit 19B.

[0074] A mode in which a secondary color is recorded using each nozzle group in one nozzle group unit is referred to as a first recording mode, and a mode in which a secondary color is recorded using each nozzle group belonging to a different nozzle group unit is referred to as a second recording mode. The control unit 11 can execute either the first recording mode or the second recording mode, for example, in response to an instruction from a user. The first recording mode is the process described above with reference to FIG. 6. That is, in the first recording mode, when recording a secondary color on the medium 30 by ejecting the first ink and the second ink using the nozzles 20 belonging to the second nozzle range 25 of the first nozzle group and the second nozzle group in the nozzle group unit 19A, the control unit 11 records the secondary color on the medium 30 by ejecting the first ink and the second ink with the ink amounts corrected by the second correction value, as described with reference to FIG. 6.

[0075] On the other hand, in the second recording mode, the second correction value is not used, but the first correction value is used. Because the second correction value is not used, steps S220, S230, and S240 in FIG. 6 are unnecessary in the second recording mode, and step S250 is executed after step S210. In other words, in the second recording mode, when a secondary color is recorded onto the medium 30 by ejecting the first ink and the second ink using the nozzles 20 belonging to the second nozzle range 25 of the first nozzle group of the nozzle group unit 19A and the second nozzle group of the nozzle group unit 19B, the control unit 11 records the secondary color onto the medium 30 by ejecting the first ink and the second ink with the ink amounts corrected by the first correction value.

[0076] The reason why the second correction value is not used in the second recording mode is because the ratio of the first distance to the second distance, which is the distance between the multiple colors between the first nozzle group and the second nozzle group, is smaller than in the first recording mode. As shown in Fig. 7, in the second recording mode, the ratio (L4 / L3) of the inter-color distance L4 between the first nozzle group and the second nozzle group in the second nozzle range 25 to the inter-color distance L3 between the first nozzle group and the second nozzle group in the first nozzle range 24 is smaller than the ratio (L2 / L1) of the inter-color distance L2 between the first nozzle group and the second nozzle group in the second nozzle range 25 to the inter-color distance L1 between the first nozzle group and the second nozzle group in the first nozzle range 24.

[0077] The inter-color distances L1 and L2 are as described in FIG. 3. The inter-color distance L3 is the inter-color distance between the nozzle group 22C of the nozzle group unit 19A and the nozzle group 22Y of the nozzle group unit 19B in the first nozzle range 24. The inter-color distance L4 is the inter-color distance between the nozzle group 22C of the nozzle group unit 19A and the nozzle group 22Y of the nozzle group unit 19B in the second nozzle range 25. In the second printing mode, when printing secondary colors using C ink and Y ink, the inter-color distance L3 is the first distance, and the inter-color distance L4 is the second distance. Naturally, there is a difference between the inter-color distances L3 and L4, but the difference is not that large in terms of the ratio between the two distances. Therefore, color unevenness in secondary colors caused by differences in the inter-color distances L3 and L4 is barely noticeable, and there is little need to use the second correction value, which is obtained by applying an offset to the first correction value.

[0078] As described above, in the first modified example, in the second print mode, which prints secondary colors using nozzle groups belonging to different nozzle group units, the difference in the ratio between the first distance and the second distance is smaller than in the first print mode, so the second correction value is not used to correct the ink amount. This makes it possible to avoid applying more correction than necessary to the ink amount and to simplify the ink amount correction process.

[0079] Second variant: The second modified example will be described based on the first modified example. In the second modified example, attention will be focused on the first recording mode. When recording a secondary color on the medium 30 by ejecting the first ink and the second ink using the nozzles 20 belonging to the second nozzle range 25 of the first nozzle group and the second nozzle group in the first nozzle group unit, if the combination of the first ink and the second ink corresponds to a specific combination, the control unit 11 records the secondary color on the medium 30 by ejecting the first ink and the second ink with the ink amount corrected by the first correction value.

[0080] A "specific combination" refers to a combination of two colors that is used relatively infrequently to print secondary colors among the combinations of two colors that can be achieved by the print head 19. As described above, in the example of Figure 7, the combination of K ink and M ink, the combination of K ink and Y ink, the combination of C ink and M ink, and the combination of C ink and Y ink each correspond to first inks and second inks having multiple inter-color distances. Among these, the specific combination is set in advance, and in this case, it is the combination of K ink and Y ink. This is because there are relatively few cases in which the same pixel has a gradation value greater than 0 for both K and Y.

[0081] That is, in the second modified example, even if the process proceeds from "Yes" in step S230 to step S240 in Fig. 6, the control unit 11 corrects the gradation values ​​of K ink and Y ink that are a specific combination among the CMYK gradation values ​​of the target pixel that are greater than 0, without using the offset value related to the secondary color of K ink and Y ink. According to this second modified example, for specific combinations that are used relatively infrequently in recording secondary colors, the ink amount correction process can be simplified by correcting the ink amount using the first correction value.

[0082] Other variations: As described above, the recording head 19 may be mounted on the carriage 18 and move together with the carriage 18. The movement of the recording head 19 by the carriage 18 is also simply referred to as movement of the recording head 19. For example, in FIGS. 2, 3, and 7, the recording head 19 may be capable of reciprocating movement parallel to the transport direction D1. In other words, the carriage 18 may perform at least a portion of the relative movement between the recording head 19 and the medium 30 in the movement direction. Therefore, not only the transport unit 17 but also the carriage 18 may correspond to the moving unit.

[0083] 2, 3, and 7, the direction in which the medium 30 is transported by the transport unit 17 may be direction D2 instead of direction D1, and the recording head 19 may move back and forth parallel to direction D1. In other words, a two-dimensional image may be recorded on the medium 30 by combining the transport of the medium 30 along direction D2, i.e., paper feed, with the reciprocating movement of the serial recording head 19 along direction D1. In this case, direction D1 is the movement direction and the width direction of the medium 30, and the carriage 18 corresponds to a moving unit that moves the recording head 19 and the medium 30 relative to each other. Furthermore, in a configuration in which direction D2 is the direction in which the medium 30 is transported by the transport unit 17, the recording head 19 may be able to move back and forth parallel to direction D2 in addition to the reciprocating movement parallel to direction D1. [Explanation of symbols]

[0084] 10... Recording device, 11... Control unit, 12... Program, 12a... Ink amount correction unit, 12b... Recording data generation unit, 12c... Recording control unit, 13... Display unit, 14... Operation reception unit, 15... Memory unit, 16... Communication IF, 17... Transport unit, 18... Carriage, 19... Recording head, 19A, 19B... Nozzle group unit, 20... Nozzle, 21C, 21M, 21Y, 21K... Nozzle row, 22C, 22M, 22Y, 22K... Nozzle group, 23... Nozzle tip, 24... First nozzle range, 25... Second nozzle range, 26... Nozzle-free section, 30... Medium, 31... Image, 40... Scanner

Claims

1. a recording head having a first nozzle group in which a plurality of nozzles for ejecting a first ink are aligned in a nozzle alignment direction, and a second nozzle group in which a plurality of nozzles for ejecting a second ink of a different color from the first ink are aligned in the nozzle alignment direction; a moving unit that moves the recording head and the medium relative to each other in a moving direction that intersects with the nozzle arrangement direction; a control unit that controls the recording head and the moving unit, The recording head includes: a first nozzle range that is a part of the first nozzle group and the second nozzle group, and in which a distance between the first nozzle group and the second nozzle group in the movement direction is a first distance; a second nozzle range that is a part of the first nozzle group and the second nozzle group, and in which the distance between the first nozzle group and the second nozzle group in the movement direction is a second distance that is longer than the first distance; The control unit, in recording on the medium using the nozzles belonging to the second nozzle range, When a primary color is recorded on the medium by ejecting either the first ink or the second ink, the primary color is recorded on the medium by ejecting either the first ink or the second ink, the ink amount of which has been corrected by a first correction value; A recording device characterized in that, when a secondary color is recorded on the medium by ejecting the first ink and the second ink, the secondary color is recorded on the medium by ejecting the first ink and the second ink with the ink amount corrected by a second correction value based on the first correction value and an offset value.

2. the recording head includes a plurality of nozzle group units each having the first nozzle group and the second nozzle group; the plurality of nozzle group units are arranged along the movement direction, The control unit when a secondary color is recorded on the medium by ejecting the first ink and the second ink using nozzles belonging to the second nozzle range of the first nozzle group and the second nozzle group in a first nozzle group unit, the secondary color is recorded on the medium by ejecting the first ink and the second ink whose ink amounts have been corrected by the second correction value; 2. The recording device according to claim 1, wherein when a secondary color is recorded on the medium by ejecting the first ink and the second ink using nozzles belonging to the second nozzle range of the first nozzle group of the first nozzle group unit and the second nozzle group of the second nozzle group unit, the secondary color is recorded on the medium by ejecting the first ink and the second ink with the ink amount corrected by the first correction value.

3. 3. The recording device according to claim 2, wherein, when recording a secondary color on the medium by ejecting the first ink and the second ink using nozzles belonging to the second nozzle range of the first nozzle group and the second nozzle group in the first nozzle group unit, if the combination of the first ink and the second ink corresponds to a specific combination that is relatively infrequently used to record a secondary color among combinations of two colors that can be realized by the recording head, the control unit records the secondary color on the medium by ejecting the first ink and the second ink with the ink amount corrected by the first correction value.

4. a recording head having a first nozzle group in which a plurality of nozzles for ejecting a first ink are aligned in a nozzle alignment direction, and a second nozzle group in which a plurality of nozzles for ejecting a second ink of a different color from the first ink are aligned in the nozzle alignment direction; a moving unit that moves the recording head and a medium relatively in a movement direction that intersects with the nozzle arrangement direction, The recording head includes: a first nozzle range that is a part of the first nozzle group and the second nozzle group, and in which a distance between the first nozzle group and the second nozzle group in the movement direction is a first distance; a second nozzle range that is a part of the first nozzle group and the second nozzle group, and in which the distance between the first nozzle group and the second nozzle group in the movement direction is a second distance that is longer than the first distance; a recording step of controlling the recording head and the moving unit to perform recording, In the recording step, when recording on the medium using nozzles belonging to the second nozzle range, When a primary color is recorded on the medium by ejecting either the first ink or the second ink, the primary color is recorded on the medium by ejecting either the first ink or the second ink, the ink amount of which has been corrected by a first correction value; A recording method characterized in that, when a secondary color is recorded on the medium by ejecting the first ink and the second ink, the secondary color is recorded on the medium by ejecting the first ink and the second ink with the ink amount corrected by a second correction value based on the first correction value and an offset value.

Images