Control device, control method, and program

Abstract

Properly adjust the ejection timing in the inkjet recording device. [Solution] A control device for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which a plurality of recording elements for applying ink to a recording medium is arranged in a first direction, is scanned in a first direction, and the recording medium is transported in a second direction intersecting the first direction, comprising: an acquisition means for acquiring a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is small, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the arrangement direction; and a determination means for determining a third adjustment value for correcting the ejection timing for each region based on the first adjustment value and the second adjustment value.

Description

[Technical Field]

[0001] This invention relates to the correction of recording position misalignment in an inkjet recording device. [Background technology]

[0002] In the industrial printing field, recording on colored or transparent recording media is sometimes required in addition to white recording media. While a single-layer color image is recorded on white recording media, two- or three-layer stacked images are recorded on transparent recording media. Therefore, recording devices are equipped with multiple recording modes. For example, in three-layer recording mode, a single recording scan records a color image for the back side, a white image that acts as an intermediate layer to shield the front and back sides, and a color image for the front side, so that different color images can be observed from both sides of the recording media. In this case, the recording device uses different nozzle areas within each nozzle row of the recording head for recording the first layer (back side), the second layer (intermediate layer), and the third layer (front side), respectively. Similarly, in two-layer recording mode, different nozzle areas within each nozzle row are used for recording the first layer and the second layer, respectively.

[0003] When recording is performed using multiple recording modes in this manner, the frequency of nozzle usage becomes uneven depending on the frequency of use of each recording mode. This can result in differences in ink ejection speed even among nozzles in the same nozzle row, potentially leading to shifts in the recording position and resulting in image defects. In relation to this problem, Patent Document 1 discloses selecting frequently used nozzles and adjusting the ejection timing to match the ejection speed from the selected nozzles. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-017974 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, as described in Patent Document 1, even if the ejection timing is adjusted to match the nozzle with the highest ejection frequency, the recording position may not be properly corrected. For example, in three-layer recording, as mentioned above, different nozzle regions of the same nozzle row are used for recording on the front and recording on the back. If the ejection frequency of the region used for recording on the front and the region used for recording on the back differ significantly, adjusting the ejection timing uniformly to match the nozzle region with the highest ejection frequency may not yield appropriate adjustment results.

[0006] This disclosure aims to appropriately adjust the ink ejection timing in an inkjet recording device. [Means for solving the problem]

[0007] This disclosure relates to a control device for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which a plurality of recording elements for applying ink to a recording medium is arranged, is scanned in a first direction, and a transport operation in which the recording medium is transported in a second direction intersecting the first direction, and comprises an acquisition means for acquiring a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is small, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the arrangement direction, and a determination means for determining a third adjustment value for correcting the ejection timing for each region based on the first adjustment value and the second adjustment value. [Effects of the Invention]

[0008] This disclosure makes it possible to appropriately adjust the ink ejection timing in an inkjet recording device. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view of the recording device. [Figure 2] This is a schematic diagram showing a cross-section of the recording section of a recording device. [Figure 3] It is a diagram showing an example of a nozzle array group of a recording head. [Figure 4] It is a diagram showing the configuration of a control system of a recording apparatus. [Figure 5] It is a diagram for explaining density detection of an optical sensor. [Figure 6] (a) It is a diagram for explaining multi-pass recording and (b) laminated recording. [Figure 7] It is a block diagram showing the functional configuration of a recording apparatus. [Figure 8] It is a diagram for explaining landing deviation due to difference in ejection speed. <000A089> [Figure 9] It is a flowchart showing the flow of adjustment value acquisition processing of the first embodiment. [Figure 10] It is a diagram for explaining a registration adjustment pattern. [Figure 11] It is a layout diagram of a registration adjustment pattern. [Figure 12] [[ID=E29]]It is a diagram showing a list of third adjustment values. [Figure 13] It is a diagram showing specific examples of the first, second, and third adjustment values. [Figure 14] It is a flowchart showing the flow of recording processing of the first embodiment. [Figure 15] It is a diagram showing the relationship between the nozzle area used in each recording mode and the third adjustment value. [Figure 16] It is a diagram showing the configuration of a control system of a recording apparatus in the second embodiment. [Figure 17] Explain the configuration and operation of a droplet detection sensor. [Figure 18] It is a flowchart showing the flow of second adjustment value acquisition processing of the second embodiment. [Figure 19] It is a diagram showing specific examples of the measured ejection speed and the second adjustment value. [Figure 20] It is a block diagram showing the functional configuration of a recording apparatus in the second embodiment. [Figure 21] It is a diagram for explaining correction of ejection timing in the second embodiment. [Figure 22]This figure shows an example of the usage ratio in a nozzle row. [Modes for carrying out the invention]

[0010] [First Embodiment] A first embodiment of this disclosure will be described in detail below with reference to the drawings.

[0011] (Configuration of an inkjet recording device) Figure 1 is a schematic perspective view showing the configuration of the inkjet recording apparatus (hereinafter referred to as the recording apparatus 100) according to this embodiment. Figure 2 is a YZ cross-sectional view schematically showing the carriage unit 102 and transport unit of the recording apparatus 100. Note that in Figure 1, the top cover is shown open in order to explain the internal mechanism of the recording apparatus 100.

[0012] As shown in Figures 1 and 2, the recording device 100 includes a carriage unit 102, a guide shaft 108, a recording head 109, a platen 104, an encoder 107, a transport roller 103, an auxiliary roller 115, a spool 106, a winding spool 112, and a heater 110.

[0013] The carriage unit 102 is supported so as to be movable in the X direction in the figure by a guide shaft 108 that extends in the X direction in the figure. The carriage unit 102 is moved back and forth in the X direction by a movement mechanism consisting of a carriage motor, carriage belt, etc. In the following description, the direction of movement of the carriage unit 102 is referred to as the main scanning direction or the X direction, and the forward movement in this X direction is referred to as the positive (X+) direction, and the return movement is referred to as the negative (X-) direction. A recording head 109 is mounted on the carriage unit 102. A flexible wiring board is attached to the recording head 109, and drive pulses for ink ejection and signals for head temperature control are supplied to it. The other end of the flexible wiring board is connected to the control unit 400 (Figure 4) of the recording device 100.

[0014] The recording head 109 moves back and forth in the main scanning direction together with the carriage unit 102, and during this time, it ejects ink according to the recording signal and drive pulse output from the control unit 400 to record onto the recording medium P.

[0015] The recording medium P is transported in a transport direction (Y direction in the figure) that intersects the main scanning direction (X direction). The transport of the recording medium P is performed by a pair of transport rollers 103 and auxiliary rollers 115 operated by a transport motor. In the following description, the transport direction of the recording medium P is referred to as the sub-scanning direction or Y direction, with the area before passing through the carriage unit 102 being the upstream side of the sub-scanning direction and the area after passing through the carriage unit 102 being the downstream side of the sub-scanning direction. Furthermore, the transport of the recording medium P from the upstream side to the downstream side is referred to as the positive (Y+) direction of the sub-scanning direction. During the transport operation of the recording medium P, the recording device 100 transports the recording medium P held on the spool 106 in the +Y direction by rotating the transport rollers 103 while holding the recording medium P with the auxiliary rollers 115. As a result, the recording medium P is guided to the recording position on the platen 104, i.e., into the scanning area of ​​the recording head 109. The platen 104 plays a role in stably supporting the recording medium P.

[0016] The recording device 100 of this embodiment is a so-called serial scanning type recording device. The serial scanning type recording device 100 alternately repeats a recording operation in which ink is ejected from each recording element arranged on the recording head 109 while scanning the recording head 109 in the main scanning direction (X direction), and a transport operation in which the recording medium P is transported in the sub-scanning direction (Y direction) which intersects the main scanning direction (X direction). In the following description, the recording element is referred to as a nozzle.

[0017] When a command to start recording is input from a host device connected to the recording device 100, the control unit 400 controls the feeding of the recording medium P to the recording position. Subsequently, once one scan's worth of recording data, i.e., one band's worth of recording data, is accumulated in the buffer, the carriage unit 102 is scanned and the recording operation is performed.

[0018] During the recording process, ink is ejected from the nozzles of the recording head 109 according to the recording data, based on the ejection timing determined by the position signal obtained from the encoder 107. This records an image in a recording area with a predetermined bandwidth in the direction of the nozzle arrangement. Subsequently, a predetermined amount of recording medium P is transported, and the next recording operation is performed. In this embodiment, as an example, the recording speed is set to 60 inches per second, and the ink ejection operation is performed at a recording resolution of 1200 dpi (1 / 1200 inch interval). However, this is just one example, and this embodiment is not limited to these values.

[0019] Furthermore, the recording device 100 of this embodiment performs so-called multi-path recording, which records an image by scanning the same area on the recording medium P multiple times with the recording head 109. Multi-path recording will be described in detail later.

[0020] An image fixing unit is provided downstream (+Y) in the transport direction relative to the recording head 109. A heater 110 is positioned in the image fixing unit. The heater 110 dries the liquid ink applied to the recording medium P by heating it. For example, a sheathed heater or a halogen heater can be used for the heater 110. The heater cover 111 covers the heater 110 and has the function of efficiently irradiating the recording medium P with the heat of the heater 110 and protecting the heater 110.

[0021] The heating temperature in the image fixing section described above is set considering the film-forming properties and productivity of the water-soluble resin fine particles, and the heat resistance of the recording medium P. Heating means in the image fixing section include hot air blowing from above and contact-type heat conduction heater heating from below the recording medium P. In this embodiment, there is only one heating means in the heating section of the image fixing section, but two or more heating means may be provided as long as the temperature measured by a radiation thermometer (not shown) on the recording medium P does not exceed the set heating temperature.

[0022] Recording is performed by the recording head 109 and the recording medium P is heated by the heater 110, then wound up by the winding spool 112 to form a roll-shaped winding medium 113.

[0023] In the above description, the movement mechanism of the carriage unit 102 was shown as an example consisting of a carriage motor and a carriage belt, but it is not limited to this example. Instead of a carriage belt, other drive methods may be used, such as providing a lead screw that is rotationally driven by a carriage motor and extends in the X direction, and driving it by engaging the groove of the lead screw with an engaging part provided on the carriage unit 102 side.

[0024] Furthermore, the nozzle surface of the recording head 109 is normally capped when the system is in standby mode. Therefore, it is necessary to open the cap before recording and make the carriage unit 102 scannable.

[0025] (Recording head configuration) Figure 3 shows an example of the nozzle surface 34 of the recording head 109. The recording head 109 has a nozzle row 33K for ejecting black ink (K), a nozzle row 33C for ejecting cyan ink (C), a nozzle row 33M for ejecting magenta ink (M), a nozzle row 33Y for ejecting yellow ink (Y), and a nozzle row 33W for ejecting white ink. The recording head 109 may also be further equipped with a nozzle row for ejecting a reactive liquid ink (RCT) that does not contain colorants. The reactive liquid ink does not contain colorants, but contains reactive components that react with the colorants contained in the colorant ink, and reacts by coming into contact with the colorant ink on the recording medium P, thereby suppressing bleeding and smudging of the colorant ink.

[0026] On the recording head 109, nozzle rows 33K, 33C, 33M, 33Y, and 33W are arranged in this order from left to right in the X direction in the diagram. Each of the nozzle rows 33K, 33C, 33M, 33Y, and 33W has 1280 nozzles 30 that eject ink, arranged in the Y direction (arrangement direction) at a density of 1200 dpi. The amount of ink droplets ejected from one nozzle 30 (ejection volume) is approximately 4.5 pl.

[0027] The nozzle rows 33K, 33C, 33M, 33Y, and 33W are each connected to ink tanks that store the corresponding ink, and ink is supplied from each ink tank. The recording head 109 and the ink tanks may be configured as an integrated unit, or they may be configured to be separable.

[0028] Each nozzle 30 of the recording head 109 is equipped with a recording element that generates ejection energy for ejecting ink. In this embodiment, an electrothermal converter is used as the recording element, which locally heats the ink to cause film boiling and ejects the ink by the resulting pressure. However, the method for generating ejection energy is not limited to this, and an electromechanical converter may also be used. Furthermore, the recording head 109 is not limited to the example shown in Figure 3. The density, arrangement, diameter, ink ejection amount, ink type, etc. of the nozzles 30 can be changed as appropriate.

[0029] (Control configuration of the recording device) Figure 4 is a block diagram showing the control configuration of the recording device 100 in this embodiment. The control unit 400 of the recording device 100 includes a CPU 401, ROM 402, RAM 403, input / output ports 404, memory 405, etc.

[0030] The CPU 401 calls and executes various programs stored in memory 405 or ROM 402 in the work area of ​​RAM 403. Based on these programs, the CPU 401 controls the operation of various parts of the recording device and processes input image data. ROM 402 functions as a memory that stores various control and image data processing programs and data executed by the CPU 401. RAM 403 temporarily holds programs loaded from memory 405 or ROM 402 and has a work area used by the CPU 401 to execute processing. RAM 403 also stores various data used to control the recording device 100. Memory 405 is a storage device such as an HDD, SSD, or flash memory. Memory 405 stores various data such as adjustment patterns and mask patterns, which will be described later. Various drivers 406, 407 and drive circuits 408, optical sensors 410, interface circuits 413, and operation panels 105 are connected to input / output ports 404. The control unit 400 controls each part connected via input / output ports 404.

[0031] The motor driver 406 is connected to various motors 409, such as the motor of the transport unit that transports the recording medium P, and the carriage motor that transports the carriage unit 102 equipped with the recording head 109. The head driver 407 is connected to the recording head 109. The drive circuit 408 is connected to the heating unit (heater) 110. In addition, drive circuits are connected to the control unit 400 for actuators in the cutting unit that cuts the recording medium P, and for other drive units (not shown). The motor drivers 406, 407, drive circuit 408, and other drive circuits drive the motors 409, the recording head 109, the heating unit (heater) 110, and actuators, etc., according to control signals from the CPU 401.

[0032] The control panel 105 includes a touch panel display and buttons, and displays information input from the CPU 401. The displayed information includes, for example, the status of the recording device 100 and information about the recording medium P. The control panel 105 also receives operations from the user and inputs operation signals to the CPU 401.

[0033] Furthermore, the control unit 400 is connected to the host device 414 via the interface circuit 413. The user inputs image data to the recording device 100 via the host device 414, and also inputs various information to the recording device 100 via the host device 414 and the operation panel 105. The host device 414 is a computer such as a PC, smartphone, or server, and sends print jobs to the recording device 100. The control unit 400 stores the received print jobs in the memory 405 or RAM 403 and performs recording operations according to the print jobs. The control unit 400 transmits information about the status of the recording device 100 and the recording medium P to the host device 414, which then displays this information on the host device 414's display.

[0034] The control unit 400 controls the drive of the transport motor and carriage motor via the motor driver 406. The control unit 400 also controls the recording head 109 via the head driver 407 to eject ink from each nozzle. The control unit 400 controls the drive of the heating unit via the drive circuit 408. Furthermore, the control unit 400 controls the drive of the optical sensor 410 and detects the optical characteristics of the adjustment pattern based on the output from the optical sensor 410. The adjustment pattern is image data for acquiring the first adjustment value and the second adjustment value, which will be described later. The adjustment pattern, the first adjustment value, and the second adjustment value will be described later.

[0035] The CPU 401 of the control unit 400 converts image data input from the host device 414 into recording data and stores it in the RAM 403. Specifically, when the CPU 401 acquires image data represented by 8-bit 256-value information (0 to 255) for each of RGB, it converts this image data into multi-level data for K, C, M, Y, and W used for recording. Through this color conversion process, multi-level data that defines the gradation of each K, C, M, Y, and W ink in each image group consisting of multiple images is generated as 8-bit 256-value information (0 to 255). Next, the CPU 401 quantizes the multi-level data for each of K, C, M, Y, and W to generate quantized data (binary data) that defines whether each K, C, M, Y, and W ink is ejected or not ejected for each pixel. The quantized data is represented as 1-bit binary information (0,1). Various known quantization methods such as error diffusion, dithering, and indexing can be used for this quantization process. Subsequently, the CPU 401 performs a distribution process to distribute the quantized data across multiple scans of the unit area of ​​the recording head 109. This distribution process generates K, C, M, Y, and W recording data for each pixel in each of the multiple scans of the unit area of ​​the recording medium P. The recording data is represented as 1-bit binary information (0,1) that determines whether each ink is ejected or not. A mask pattern is used in this distribution process to determine whether ink ejection is permitted or not for each pixel, corresponding to multiple scans. The generation of such recording data is not limited to being performed by the control unit 400; the host device 414 may perform some or all of the processing, and the control unit 400 may perform the remaining processing.

[0036] (Optical sensor) The optical sensor 410 will be described with reference to Figure 5. Figure 5(a) is a diagram showing the schematic configuration of the optical sensor 410. In Figure 5(a), the left-right direction is the X direction (carriage movement direction), the direction perpendicular to the paper plane is the Y direction (conveyance direction of the recording medium P), and the up-down direction of the figure is the Z direction (gravity direction). The recording medium P is transported with the front side of the paper plane being the upstream side and the depth side being the downstream side.

[0037] The optical sensor 410 is fixedly mounted on the carriage unit 102 such that its measuring section is located downstream in the Y direction from the multiple rows of nozzles provided on the recording head 109. The lower surface 500 of the optical sensor 410 is positioned so as to coincide with the nozzle surface 34 (Figure 3) in the Z direction, or above the nozzle surface 34 in the Z direction (upper side of the figure).

[0038] The optical sensor 410 has a light-emitting unit 502 realized by a visible LED such as red, green, or blue, and a light-receiving unit 504 realized by a photodiode. The light-emitting unit 502 and the light-receiving unit 504 are provided on the lower surface 500 of the optical sensor 410. The light-emitting unit 502 irradiates light onto the recording medium P, and the light-receiving unit 504 receives the reflected light reflected from the recording medium P. Therefore, in the optical sensor 410, the light 506 irradiated from the light-emitting unit 502 is diffusely reflected by the recording medium P, and this reflected light 508 is received by the light-receiving unit 504.

[0039] Figure 5(b) shows the detection spot of the light-receiving section 504 of the optical sensor 410. The diameter of the detection spot 510 of the light-receiving section 504 is, for example, approximately 3 mm in diameter. In Figure 5(b), the left-right direction is the X direction (main scanning direction), the direction perpendicular to the paper plane is the Z direction (gravity direction), and the up-down direction of the figure is the Y direction (transport direction of the recording medium P). The light-receiving section 504 transmits the detection signal (analog signal) of the received reflected light 508 to the control circuit on the electrical board of the recording device 100 via a flexible cable (not shown) or the like. The A / D converter in the control circuit converts the analog detection signal into a digital signal.

[0040] In the recording of the adjustment pattern and detection of optical characteristics, which will be described later, the transport of the recording medium P in the Y direction and the movement of the carriage unit 102 to which the optical sensor 410 is attached in the X direction are performed alternately. The control unit 400 controls the timing of ink ejection in synchronization with the timing based on the position signal obtained from the encoder 107 to record the adjustment pattern at a predetermined position on the recording medium P. The optical sensor 410 detects the density of the adjustment pattern recorded on the recording medium P as optical reflectance.

[0041] (ink) Next, the K, C, M, Y, and W inks used in this embodiment will be described. These inks contain a solid component for recording images and a volatile liquid component. Examples of solid components include colorants such as pigments and dyes, and examples of liquid components include water and water-soluble organic solvents. Each ink contains water-soluble resin fine particles to ensure close adhesion between the recording medium and the colorant, thereby improving the scratch resistance (fixability) of the recorded image.

[0042] (Recording medium) The recording device 100 of this embodiment records on a low-permeability recording medium that is resistant to moisture penetration. A low-permeability recording medium, as described above, is a medium that has no water absorption or absorbs very little water. Therefore, with water-based inks that do not contain organic solvents, the ink is repelled and images cannot be recorded. On the other hand, it has excellent water resistance and weather resistance and is suitable as a recording medium for recording materials used outdoors. Typically, a recording medium is used in which the water contact angle at 25°C is 45° or more, preferably 60° or more.

[0043] Low-permeability recording media include recording media in which a plastic layer is formed on the outermost surface of the substrate, recording media in which no ink-receiving layer is formed on the substrate, or sheets, films, banners, etc., made of glass, Yupo, plastic, etc. Examples of the coated plastics mentioned above include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene. Because these low-permeability recording media have excellent water resistance, light resistance, and abrasion resistance, they are generally used for recording materials for outdoor displays.

[0044] (Multipath recording method) The recording device 100 of this embodiment records images by so-called multi-pass recording, which uses K, C, M, Y, and W inks and records a predetermined area (1 / n band) on the recording medium P by scanning it multiple times (n times). First, multi-pass recording using the entire nozzle row area will be explained below using W ink and K ink as examples.

[0045] Figure 6(a) illustrates an 18-pass multi-pass recording method that uses the entire nozzle range of the W ink and K ink. Here, W ink and K ink are ejected from each of the nozzle regions A1 to A18, which are 18 sections divided in the Y direction from each nozzle row 33W and 33K, for each of the 18 scans of a predetermined area 60 on the recording medium P. The recording data for the W ink and K ink are distributed to each scan so that the image recording is completed in 18 scans. In reality, the recording medium P is transported downstream in the Y direction (Y(+) direction) between the k-th scan and the (k+1)-th scan of the recording head 109, but for the sake of explanation, Figure 6(a) shows the recording head 109 moving upstream in the Y direction (Y(-) direction) relative to the recording medium P.

[0046] First, in the first scan (1st scan), W ink and K ink are ejected from nozzle area A1 within nozzle rows 33W and 33K to a predetermined area 60 on the recording medium P, according to the W ink and K ink recording data corresponding to the 1st scan. After the completion of this 1st scan, the recording medium P is transported in the Y direction by a distance corresponding to one nozzle area. Then, the second scan (2nd scan) is performed, and ink is ejected to the predetermined area 60 from nozzle area A2. Subsequently, the transport of the recording medium P and the ejection of ink from the recording head 109 alternate, and ink is ejected from nozzle areas A3 to A18 to the predetermined area 60 in the 3rd to 18th scans, respectively. In this way, multi-pass recording to the predetermined area 60 is completed.

[0047] (Multiple recording modes) In this embodiment, the recording device 100 records not only on white recording media but also on colored and transparent recording media. In particular, for transparent recording media, K, C, M, and Y color inks and W ink are layered and recorded. Multiple recording modes with different layering conditions will be explained using Figure 6(b). In this explanation, only K ink will be described as a representative of the color inks.

[0048] Single-layer recording Single-layer recording is a recording mode primarily used when recording on white recording media, and all nozzles 601K and 601W in each nozzle row corresponding to each ink color are used.

[0049] • Dual-layer recording (overflood mode: OF mode) In OF mode of two-layer recording, the recording device 100 first records a color image on a transparent recording medium using color ink. Next, the recording device 100 records W ink on top of the image recorded with color ink. This allows the user to view the color image when observing it from the back of the recording medium. In OF mode recording, the recording device 100 first records a color image using the nozzles of a specific nozzle area 602K within the nozzle row 33K corresponding to the color ink. Then, the recording device 100 stacks the white image on top of the color image using the nozzles of a specific nozzle area 602W within the nozzle row 33W corresponding to the W ink. Nozzle area 602K is one of the regions divided in the direction of arrangement within the nozzle row 33K, and in Figure 6(b), it is the nozzle region shown A1 to A10. Nozzle area 602W is one of the regions divided in the direction of arrangement within the nozzle row 33W, and in Figure 6(b), it is the nozzle region shown A11 to A18.

[0050] • Dual-layer recording (Underflood mode: UF mode) In the two-layer recording UF mode, the recording device 100 first records a background image on a transparent recording medium using W ink. Next, the recording device 100 records a color image on top of the background image recorded with W ink using color ink. This allows the user to see the color image when viewed from the surface of the recording medium. In recording in UF mode, the recording device 100 first records the background image using the nozzles of a specific nozzle area 603W of the nozzle row 33W corresponding to the W ink. Then, the recording device 100 records a color image on top of the background image using the nozzles of a nozzle area 603K of the nozzle row 33K corresponding to the color ink. Nozzle area 603W is one of the regions divided in the direction of arrangement within the nozzle row 33W, and in Figure 6(b), it is the nozzle area shown A1 to A10. Nozzle area 603K is one of the regions divided in the direction of arrangement within the nozzle row 33K, and in Figure 6(b), it is the nozzle area shown A11 to A18.

[0051] • 3-layer recording (Sandwich mode: SW mode) In SW mode of 3-layer recording, the recording device 100 first records a first color image on a transparent recording medium using color ink. Next, the recording device 100 records an intermediate shielding layer on top of the color image recorded with color ink using W ink. Furthermore, the recording device 100 records a second color image on top of the intermediate shielding layer recorded with W ink. This allows the user to see the first color image when viewed from the back of the recording medium and the second color image when viewed from the front. In SW mode recording, the recording device 100 records the first color image using a nozzle in a specific nozzle area 604K1 of the nozzle row 33K corresponding to the color ink. Next, the recording device 100 records a white image of the intermediate shielding layer on top of the first color image using a nozzle in a specific nozzle area 604W of the nozzle row 33W corresponding to the W ink. Subsequently, the recording device 100 records a second color image on top of the white image of the intermediate shielding layer using a nozzle in a specific nozzle area 604K2 of the nozzle row 33K corresponding to the color ink. Nozzle region 604K1 is one of the regions divided in the direction of arrangement within the nozzle row 33K, and in Figure 6(b), it is the nozzle region shown A1 to A6. Nozzle region 604W is one of the regions divided in the direction of arrangement within the nozzle row 33W, and in Figure 6(b), it is the nozzle region shown A7 to A12. Nozzle region 604K2 is one of the regions divided in the direction of arrangement within the nozzle row 33K, and in Figure 6(b), it is the nozzle region shown A13 to A18.

[0052] Thus, in multilayer recording, even within the same nozzle array, there are areas used for recording and areas that are not.

[0053] (Functional Configuration) Next, the functional configuration of the recording device 100 according to this embodiment will be described. Figure 7 is a block diagram showing the functional configuration of the recording device 100. Note that Figure 7 shows the functional configuration related to register adjustment in this embodiment.

[0054] As described above, the recording head 109 used in this embodiment moves in the main scanning direction (X direction) of the carriage unit 102, and has multiple nozzles arranged in the Y direction intersecting the main scanning direction. Multiple such nozzle rows are arranged in the main scanning direction (X direction) of the carriage unit 102 for each ink color. In a recording device 100 using such a recording head 109, it is necessary to perform a process to determine the appropriate ejection timing in order to match the landing positions of the ink droplets ejected from each nozzle row 33K, 33C, 33M, 33Y, and 33W. This process is called register adjustment. In a recording device 100 having multiple recording modes as described above, the frequency of use of each nozzle in the nozzle row will be uneven depending on the frequency of use of each recording mode. In each nozzle, colorants such as pigments may burn and adhere to the inside of the nozzle due to film boiling caused by ink heating during ejection. In nozzles that are used frequently, the ejection speed may change, such as a decrease in ejection speed due to the adhesion of burnt material. As a result, the ejection speed will be slower in the nozzle region that is used relatively frequently within a single nozzle row, creating an ejection speed difference between it and the other nozzle regions. In such cases, even if the ejection timing is adjusted on a per-nozzle row basis, the misalignment of the projectiles due to the ejection speed within the nozzle row may not be corrected, potentially resulting in image defects.

[0055] Therefore, in the first embodiment of this disclosure, the control unit 400 of the recording device 100 first acquires an adjustment value as a first adjustment value for correcting the ink ejection timing in each nozzle row so that the impact misalignment in the main scanning direction (X direction) is reduced. Specifically, it acquires bidirectional register adjustment values ​​for each nozzle row and register adjustment values ​​between nozzle rows. Bidirectional means forward movement and backward movement in the main scanning direction. Also, since each nozzle row corresponds to an ink color, the register adjustment value between nozzle rows is hereinafter referred to as the inter-color register adjustment value. These bidirectional register adjustment values ​​and inter-color register adjustment values ​​are acquired with reference to a predetermined nozzle area of ​​the nozzle row. The nozzle area used to acquire these bidirectional register adjustment values ​​and inter-color register adjustment values ​​is referred to as the reference nozzle area.

[0056] The control unit 400 also acquires a second adjustment value to correct for the misalignment of ink droplets caused by the difference in ink ejection speed between nozzle regions, which are divided in the direction of the arrangement of each nozzle row. Specifically, for each nozzle row, the control unit 400 acquires a second adjustment value based on the difference between the bidirectional misalignment amount of each nozzle region and the bidirectional misalignment amount of the reference nozzle region in the bidirectional registration adjustment of the first adjustment value described above. When calculating the third adjustment value, which will be described later, by adding the second adjustment value to the first adjustment value, an offset is set based on the reference nozzle region of the first adjustment value so that the adjustment value does not shift. In the following explanation, this offset value will also be included in the second adjustment value.

[0057] The control unit 400 determines a third adjustment value for correcting the ejection timing based on the first and second adjustment values. The third adjustment value is determined for each nozzle region of each nozzle row, with adjustment values ​​for the forward and reverse directions. The control unit 400 corrects the impact misalignment of each nozzle region of each nozzle row according to the determined third adjustment value. This correction of impact misalignment is achieved by correcting the ink ejection timing of the corresponding nozzle row and nozzle region in accordance with the third adjustment value. In this embodiment, the first, second, and third adjustment values ​​are described as values ​​that include the amount (distance) of the impact position shift and the direction of the shift (sign + or -). However, if the carriage movement speed is fixed, the amount (time) of the ejection timing shift and the direction of the shift (sign + or -) are uniquely determined from the amount and direction of the impact position shift. Therefore, the first, second, and third adjustment values ​​may be expressed as values ​​that indicate the amount and direction of the ejection timing shift.

[0058] Figure 7 is a block diagram showing the functional configuration for achieving ejection timing correction. As shown in the figure, the control unit 400 of the recording device 100 includes a recording mode acquisition unit 700, a first adjustment value acquisition unit 701, a second adjustment value acquisition unit 702, a third adjustment value determination unit 703, and an ejection timing correction unit 704. In this embodiment, each of these functional units is realized by the CPU 401 calling a program stored in the non-volatile storage area of ​​the ROM 402 or RAM 403 and executing processing according to the program.

[0059] The recording mode acquisition unit 700 acquires the recording mode. The recording mode is acquired from the host device 414 as information included in the print job, or it is specified by the user via the operation panel 105. In this embodiment, the recording mode of the recording device 100 is one of the following, as described above: single-layer recording mode, two-layer recording mode (OF mode, UF mode), or three-layer recording mode (SW mode). However, the recording mode is not limited to these and may include other recording modes.

[0060] The first adjustment value acquisition unit 701 acquires a first adjustment value. The first adjustment value is an adjustment value for correcting the misalignment of the recording position in the main scanning direction (X direction) of the recording head 109. In this embodiment, the first adjustment value acquisition unit 701 acquires a first adjustment value that includes, as adjustment items for the first adjustment value, an adjustment value for bidirectional registration adjustment and an adjustment value for inter-color registration adjustment. Bidirectional registration adjustment is an adjustment for correcting the misalignment of the bullet impact between forward recording and reverse recording. Inter-color registration adjustment is an adjustment for correcting the misalignment of the bullet impact between different nozzle rows. Each of these registration adjustments is performed in a reference nozzle area within a nozzle row.

[0061] Figure 8 is a schematic diagram illustrating the impact misalignment between the reciprocating scans of the recording head 109. The recording head 109 ejects ink from each nozzle while moving back and forth in the X direction. In the following explanation, the right side of Figure 8 is considered the positive X direction, and the movement of the recording head 109 in the positive X direction is called the forward scan. The left side of Figure 8 is considered the negative X direction, and the movement of the recording head 109 in the negative X direction is called the reverse scan. Ra and Rb represent the flight trajectories of the ejected ink at different ejection speeds Va and Vb, respectively. Ra is the flight trajectory at a high ejection speed (Va) (solid arrow), and Rb is the flight trajectory at a slower ejection speed (Vb) (dotted arrow). The ink ejection speed from a nozzle correlates with the frequency of use of that nozzle; when the nozzle is used frequently, the ejection speed tends to be slower compared to when it is used infrequently.

[0062] As shown in Figure 8, at ejection speed Va, we assume that the impact positions in the forward and return directions are approximately the same. At ejection speed Vb, the flight time of the ink droplet until it impacts the recording medium P is relatively longer compared to the case of ejection speed Va. Therefore, the droplets impact at positions ahead of the scanning direction in both the forward and return directions, resulting in an impact misalignment between the impact positions in the forward and return directions. If the impact misalignment amount L is the distance from the impact position in the forward direction to the impact position in the return direction, the impact misalignment amount La is approximately 0 at ejection speed Va. Also, at ejection speed Vb, the impact misalignment amount Lb is a negative value (for example, -2 here), with the forward direction being positive. To eliminate this bidirectional impact misalignment, the impact position in the return direction should be shifted in the positive direction by an amount (distance) that cancels out the impact misalignment amount L. This shift amount (for example, +2) becomes the bidirectional registration adjustment value. Furthermore, the registration adjustment value is converted into a value that adjusts the discharge timing (discharge time) and is used to correct the discharge timing. A positive registration adjustment value corresponds to a correction in the positive X direction, and a negative registration adjustment value corresponds to a correction in the negative X direction. The target impact position is corrected by shifting it by the registration adjustment value relative to the reference impact position. In bidirectional registration, the forward impact position is the reference, and the return impact position is the target of adjustment. Specifically, in the example in Figure 8, the bidirectional registration adjustment value Qa at discharge speed Va is 0, and no correction is made to the return impact position that is the target of adjustment. The bidirectional registration adjustment value Qb at discharge speed Vb is +2, and the discharge timing is corrected so that the return impact position that is the target of adjustment is shifted by a distance equivalent to +2.

[0063] The -2 and +2 values ​​representing the displacement and adjustment values ​​mentioned above are calculated by setting a predetermined unit length to 1. The predetermined unit length is, for example, 5 [μm]. The register adjustment value may also be expressed as a value indicating the displacement distance, or as an adjustment value for the discharge timing (time). When the carriage movement speed is constant, the discharge timing adjustment value can be uniquely derived from the displacement amount (unit: distance).

[0064] Here, we will explain how to obtain the register adjustment value. Figure 9 is a flowchart showing the procedure for obtaining the register adjustment value. In the process shown in this flowchart, a program stored in the ROM 402 of the control unit 400 of the recording device 100 is called by the CPU 401, loaded into the RAM 403, and executed by the CPU 401. When the CPU 401 receives a command to start processing based on user operation from the operation panel 105, it starts this process. In the following explanation, the symbol "S" means step.

[0065] In S901, the CPU 401 first performs light intensity adjustment of the optical sensor 410.

[0066] In S902, the CPU 401 reads recording data for recording the adjustment pattern from the memory 405, drives the recording head 109 and motor 409 to record the read adjustment pattern on the recording medium P.

[0067] Figures 10(a) and 10(b) show examples of adjustment patterns recorded on the recording medium P. Figure 10(a) shows an example of the configuration of the adjustment pattern. The adjustment pattern includes a reference pattern 1001 and a shift pattern 1002. In Figure 10(a), for illustrative purposes, the reference pattern 1001 and the shift pattern 1002 are shown side by side in the vertical direction, but in reality, the reference pattern 1001 and the shift pattern 1002 are recorded superimposed on each other. That is, the reference pattern 1001 is recorded superimposed on the shift pattern 1002 which is shifted by a predetermined number of pixels a in the main scanning direction (X direction in the figure).

[0068] These adjustment patterns are recorded by periodically repeating an i-pixel × n-pixel rectangular pattern in the main scanning direction for every m-pixel blank area. The shift pattern 1002 is recorded at a recording position shifted by a predetermined number of pixels a relative to the reference pattern 1001. The resolution and shift amount of the reference pattern 1001 and the shift pattern 1002 can be determined according to the recording resolution of the recording device 100. In this embodiment, the recording resolution is assumed to be 1200 dpi.

[0069] Figure 10(b) shows a configuration in which multiple adjustment patterns, as shown in Figure 10(a), are arranged in the main scanning direction (X direction). In this case, the adjustment pattern group 1010 shown in Figure 10(b) is recorded while changing the shift amount a of the shift pattern 1002 from -3 pixels to +3 pixels. As can be seen from Figure 10(b), when the shift amount is 0, the reference pattern 1001 and the shift pattern 1002 are recorded overlapping. On the other hand, as the shift amount increases, the difference between the reference pattern 1001 and the shift pattern 1002 increases, so the width of the pattern is recorded wider. Note that in Figure 10(b), for convenience, an example is shown in which the difference between the reference pattern 1001 and the shift pattern 1002 is small when the shift amount is 0. However, when adjustment patterns are actually recorded, the position where the difference between the reference pattern 1001 and the shift pattern 1002 is small will differ depending on various conditions. When the amount of displacement between the recording positions of the reference pattern 1001 and the shifted pattern 1002 changes, the area ratio of ink occupying the recording medium changes, as shown in Figure 10(b).

[0070] In S903, the CPU 401 reads the adjustment pattern recorded on the recording medium P using the optical sensor 410 and detects the optical characteristics. Specifically, it reads the density value from the recorded adjustment pattern.

[0071] In S904, CPU401 determines the register adjustment value based on the optical characteristics detected in S903.

[0072] Figure 10(c) is a graph 1020 showing the relationship between the amount of positional shift of the shift pattern 1002 in the adjustment pattern and the optical reflectance. The horizontal axis represents the amount of positional shift, and the vertical axis represents the optical reflectance. The optical reflectance is inversely proportional to the density of the adjustment pattern recorded by the optical sensor 410 as shown in Figure 10(b). In other words, the smaller the positional shift between the reference pattern 1001 and the shift pattern 1002 actually recorded on the recording medium P, the lower the density. That is, patterns with higher reflectance are patterns with less positional shift. Therefore, the register adjustment value should be determined from the shift amount a with the lowest density of the adjustment pattern.

[0073] In S905, the CPU 401 stores the determined register adjustment value in RAM 403 or memory 405. Subsequently, the CPU 401 feeds the recorded adjustment pattern to the image fixing unit and fixes it, taking care to prevent contamination by the ink used to record the adjustment pattern. This completes the registration adjustment value acquisition process.

[0074] In this way, the registration adjustment value is determined by recording the adjustment pattern and detecting the density by the optical sensor 410. The nozzle rows used to record the reference pattern 1001 and the shift pattern 1002 are determined by the combination of the ink color and scanning direction of the nozzle row to be adjusted. The nozzle row to be adjusted is determined according to the adjustment item. In bidirectional registration adjustment, the reference pattern 1001 is recorded in the forward direction in a predetermined area of ​​the nozzle row of the ink color to be adjusted, and the shift pattern is recorded in the reverse direction in the same nozzle area of ​​the same nozzle row. From the density detection result of the recorded adjustment pattern, a registration adjustment value (bidirectional registration adjustment value) is obtained to correct the impact misalignment of the reverse direction recording relative to the forward direction recording of the ink color to be adjusted. For example, in bidirectional registration adjustment of ink color K, for example, the reference pattern 1001 is recorded in the forward direction in the nozzle area (A1, A2) of nozzle row 33K, the shift pattern 1002 is recorded in the reverse direction in the same nozzle area (A1, A2) of the same nozzle row, and the bidirectional registration adjustment value for ink color K is obtained. Furthermore, in inter-color registration adjustment, a reference pattern is recorded in the forward direction recording of a predetermined nozzle area of ​​nozzle row 33K, and a shift pattern is recorded in the forward direction recording of the same nozzle area of ​​the nozzle row of the ink color to be adjusted. From the density detection results of the recorded adjustment pattern, a registration adjustment value is obtained to correct the impact shift of the forward direction recording of the ink color to be adjusted relative to the forward direction recording of ink color K. In inter-color registration adjustment between ink colors K and W, for example, a reference pattern 1001 is recorded in the forward direction recording of the nozzle area (A17, A18) of nozzle row 33K, a shift pattern 1002 is recorded in the forward direction recording of the same nozzle area (A17, A18) of nozzle row 33W, and an inter-color registration adjustment value for W relative to ink color K is obtained.

[0075] Figure 11(a) shows which adjustment pattern is assigned to each nozzle area of ​​the nozzle row in the process of acquiring the first adjustment value. For example, in bidirectional registration adjustment of ink color K, the control unit 400 records the adjustment pattern (1_Bi_K) using the nozzle areas (A1, A2) of nozzle row 33K. In bidirectional registration adjustment of ink color C, the control unit 400 records the adjustment pattern (1_Bi_C) using the nozzle areas (A3, A4) of nozzle row 33C. In bidirectional registration adjustment of ink color M, the control unit 400 records the adjustment pattern (1_Bi_M) using the nozzle areas (A5, A6) of nozzle row 33M. In bidirectional registration adjustment of ink color Y, the control unit 400 records the adjustment pattern (1_Bi_Y) using the nozzle areas (A7, A8) of nozzle row 33Y. In the bidirectional registration adjustment of ink color W, the control unit 400 records the adjustment pattern (1_Bi_W) using the nozzle area (A9, A10) of the nozzle row 33W.

[0076] Furthermore, for color registration adjustment between ink colors K and C, the control unit 400 records the adjustment pattern (1_K-C) using the nozzle areas (A11, A12) of nozzle rows 33K and 33C. For color registration adjustment between ink colors K and M, the control unit 400 records the adjustment pattern (1_K-M) using the nozzle areas (A13, A14) of nozzle rows 33K and 33M. For color registration adjustment between ink colors K and Y, the control unit 400 records the adjustment pattern (1_K-Y) using the nozzle areas (A15, A16) of nozzle rows 33K and 33Y. For color registration adjustment between ink colors K and W, the control unit 400 records the adjustment pattern (1_K-W) using the nozzle areas (A17, A18) of nozzle rows 33K and 33W.

[0077] Thus, the control unit 400 acquires bidirectional registration adjustment values ​​and inter-color registration adjustment values ​​using the allocated reference nozzle area as shown in Figure 11(a).

[0078] Returning to the explanation of Figure 7, the second adjustment value acquisition unit 702 acquires an adjustment value as the second adjustment value to correct the projectile misalignment caused by the difference in discharge speed for each nozzle region within each nozzle row. Specifically, for each nozzle row, the second adjustment value acquisition unit 702 acquires an adjustment value that correlates with the bidirectional register adjustment value for each nozzle region. Then, it determines the second adjustment value based on the difference between the adjustment value correlated with the acquired bidirectional register adjustment value for each nozzle region and the first adjustment value relative to the reference nozzle in bidirectional register adjustment.

[0079] The method for obtaining the second adjustment value is described below. Figure 11(b) shows the assignment of the register adjustment pattern for obtaining the second adjustment value. In the following explanation, the adjustment of nozzle row 33K that ejects ink of ink color K will be described as an example, but the same applies to other ink colors.

[0080] As described above, each nozzle row is divided into multiple nozzle regions containing multiple nozzles in the direction of its arrangement. A second adjustment value is determined for each nozzle region in each nozzle row. Figure 11(b) shows an example in which a nozzle row is divided into nine nozzle regions. The control unit 400 controls the recording of the adjustment pattern in each nozzle region according to the assignment in Figure 11(b). The adjustment pattern to be recorded in order to obtain the second adjustment value is the same as the adjustment pattern shown in Figures 10(a) and (b).

[0081] Specifically, for the nozzle row 33K, the control unit 400 uses the nozzle areas (A1, A2) of the nozzle row 33K to record the reference pattern 1001 in forward recording and the shift pattern 1002 in reverse recording of the same nozzle area of ​​the same nozzle row. This records the adjustment pattern (2_K1) on the recording medium P. Similarly, the adjustment pattern (2_K2) is recorded using the nozzle areas (A3, A4) of the nozzle row 33K, and the adjustment pattern (2_K3) is recorded using the nozzle areas (A5, A6) of the nozzle row 33K. For other adjustment patterns as well, the control unit 400 uses each nozzle area of ​​each nozzle row to record the reference pattern 1001 shown in Figure 10(a) in forward recording and the shift pattern 1002 in reverse recording of the same nozzle area of ​​the same nozzle row. Note that each adjustment pattern is the same as the adjustment pattern (1_Bi_K) used for bidirectional register adjustment to acquire the first adjustment value, but the method of calculating the adjustment value is different. As mentioned above, the bidirectional registration adjustment value is an adjustment value used to cancel out the amount L of the deviation in the landing position in the return direction relative to the reference landing position in the forward direction. In other words, it is an adjustment value that shifts the landing position in the return direction by -L. In contrast, the second adjustment value is an adjustment value that corrects the landing deviation caused by the difference in discharge speed between nozzle regions within the nozzle row. In other words, it is an adjustment value that corrects the landing deviation between nozzle regions within the same scan (forward or return direction). Therefore, since it is an adjustment value that cancels out half of the landing deviation amount L in each scanning direction, both forward and return, its magnitude is half that of the bidirectional registration adjustment value.

[0082] Furthermore, the second adjustment value may be obtained as a relative adjustment value for other nozzle regions with respect to the adjustment value of the reference nozzle region, using the nozzle region allocated for bidirectional register adjustment in the acquisition of the first adjustment value within each nozzle row as the reference nozzle region. Therefore, the second adjustment value may be managed by offsetting it by the adjustment value acquired in the reference nozzle region. To explain this specifically using the example in Figure 8, if the discharge speed of the reference nozzle region is Vb and the discharge speed of the nozzle region to be adjusted is Va, the second adjustment value of the reference nozzle region is obtained as +1 by dividing the bidirectional register adjustment value +2 by 2. The second adjustment value of the nozzle region to be adjusted is obtained as 0 by dividing the bidirectional register adjustment value 0 by 2. In this case, the second adjustment value of the reference nozzle region is offset by -1 so that it becomes 0, and the second adjustment value of the reference nozzle region is obtained as 0 and the second adjustment value of the nozzle region to be adjusted is obtained as -1.

[0083] The acquisition of the second adjustment value is performed by the CPU 401 controlling each part of the recording device 100 based on the user's start command. The acquisition of the second adjustment value may also be performed together with the acquisition of the first adjustment value. In this case, at S902 in the flowchart of Figure 9, the CPU 401 records the adjustment pattern for acquiring the first adjustment value and the adjustment pattern for acquiring the second adjustment value. Then, at S903, the CPU 401 reads the density value using the optical sensor 410 from the adjustment pattern for acquiring the first adjustment value and the adjustment pattern for acquiring the second adjustment value recorded in S902. At S904, the CPU 401 determines the first and second adjustment values ​​based on the reading result in S903. At S904, the CPU 401 stores the determined first and second adjustment values ​​in the RAM 403 and terminates the process. Thus, when acquiring both the first and second adjustment values ​​together, the user only needs to initiate the process once, making it efficient.

[0084] The third adjustment value determination unit 703 corrects the first adjustment value acquired by the first adjustment value acquisition unit 701 based on the second adjustment value acquired by the second adjustment value acquisition unit 702, and determines the third adjustment value. The determination of the third adjustment value will be explained below.

[0085] Figure 12 is a diagram showing a list of third adjustment values ​​determined by the third adjustment value determination unit 703. As shown in Figure 12, based on the forward direction recording of the nozzle region (A1, A2) of nozzle row 33K, the third adjustment values ​​for the forward and return directions are determined for each of the nine nozzle regions (A1, A2), (A3, A4), (A5, A6), (A7, A8), (A9, A10), (A11, A12), (A13, A14), (A15, A16), and (A17, A18) in each nozzle row 33K, 33C, 33M, 33Y, and 33W.

[0086] As mentioned above, the first adjustment values ​​acquired by the first adjustment value acquisition unit 701 include the bidirectional register adjustment values ​​of the nozzle rows 33K, 33C, 33M, 33Y, and 33W for each ink color, and the inter-color register adjustment values ​​between K and the other ink colors. The nozzle area that records the adjustment pattern for each adjustment item (bidirectional, inter-color) is the reference nozzle area for each adjustment item. In other words, the reference nozzle area for the bidirectional register adjustment value (1_Bi_K) of ink color K is (A1, A2). The reference nozzle area for the bidirectional register adjustment value (1_Bi_C) of ink color C is (A3, A4). The reference nozzle area for the bidirectional register adjustment value (1_Bi_M) of ink color M is (A5, A6). The reference nozzle area for the bidirectional register adjustment value (1_Bi_Y) of ink color Y is (A7, A8). The reference nozzle area for the bidirectional registration adjustment value (1_Bi_W) of ink color W is (A9, A10).

[0087] Furthermore, the reference nozzle area for the inter-color registration adjustment value (1_K_C) between ink colors K and C is (A11, A12). The reference nozzle area for the inter-color registration adjustment value (1_K_M) between ink colors K and M is (A13, A14). The reference nozzle area for the inter-color registration adjustment value (1_K_Y) between ink colors K and Y is (A15, A16). The reference nozzle area for the inter-color registration adjustment value (1_K_W) between ink colors K and W is (A17, A18). These first adjustment values ​​are suitable registration adjustment values ​​when there is no difference in ejection speed within the nozzle row.

[0088] The adjustment value detected by the second adjustment value acquisition unit 702 from the adjustment pattern is an adjustment value for correcting the impact misalignment caused by the difference in ink ejection speed between nozzle areas of each ink color, and is a value correlated with the bidirectional register adjustment value for each nozzle area. Therefore, if there is a difference in the detected value within a nozzle row of the same ink color, the second adjustment value acquisition unit 702 acquires a third adjustment value by reflecting the difference between the detected value in the above-mentioned reference nozzle area and the detected value in the target nozzle area into the first adjustment value acquired in the other nozzle area. The third adjustment value is determined based on the following equations (1) to (4).

[0089] P1=P1 color distance+P1 bidirectional...(1) P2 = Adjustment value within the nozzle row (relative adjustment value based on the bidirectional register adjustment nozzle) ... (2) Forward: P3=P1-P2+P2 offset ...(3) Return direction: P3=P1+P2+P2 offset ...(4)

[0090] Here, P1 is the first adjustment value, P2 is the second adjustment value, and P3 is the third adjustment value. offset This is determined for each nozzle row based on the reference nozzle area used to obtain the first adjustment value and the second adjustment value.

[0091] Figure 13 is a diagram that specifically explains how to obtain the first to third adjustment values. In Figure 13, nozzle rows 33K and 33M are explained as examples.

[0092] Figure 13(a) conceptually shows an example of the impact position for nozzle rows 33K and 33M without registration adjustment. The impact position is shown with the forward direction as +. Figure 13(b) is a table showing the first adjustment value P1 obtained from the adjustment pattern for obtaining the first adjustment value. Note that the recording device does not acquire and manage information on the impact position as shown in Figure 13(a), but acquires and manages relative adjustment values ​​as shown in Figure 13(b). This is described here as an example for the purpose of explaining the acquisition of adjustment values. According to the table shown in Figure 13(a), the bidirectional impact deviation in the reference nozzle area (A1, A2) of nozzle row 33K is (-1)-0=-1. Therefore, the bidirectional adjustment value for nozzle row 33K is "+1", and the nozzle to be corrected is the return direction of 33K. Also, the bidirectional impact deviation in the reference nozzle area (A5, A6) of nozzle row 33M is 2-6=-4. Therefore, the bidirectional registration adjustment value (P bidirectional) for nozzle row 33M is "+4", and the nozzle to be corrected is the return direction of 33M. Also, the impact misalignment between colors in nozzle rows 33K and 33M is obtained in the reference nozzle area (A13, A14) and is 10-2=8. Therefore, the inter-color registration adjustment value (P inter-color) for nozzle rows 33K and 33M is "-8". The nozzle to be corrected is the forward / return direction of 33M.

[0093] Next, we will explain the second adjustment value. Figure 13(c) shows the bidirectional impact deviation values ​​for each nozzle region obtained from the adjustment pattern for acquiring the second adjustment value for nozzle rows 33K and 33M. Figure 13(d) shows the value obtained by canceling out the bidirectional impact deviation shown in Figure 13(c) and dividing by 2. For example, the bidirectional impact deviation for nozzle region (A1, A2) of nozzle row 33K is "-1", so the value obtained by dividing the canceling value by 2 is "0.5". Similarly, the bidirectional impact deviation for nozzle region (A5, A6) of nozzle row 33M is "-4", so the value obtained by dividing the canceling value by 2 is "2".

[0094] The adjustment values ​​for each nozzle region calculated in this way (Figure 13(d)) are managed by offsetting them so that the amount of deviation in the reference nozzle region from which the bidirectional registration adjustment value of the first adjustment value was obtained becomes "0". The reference nozzle region for the bidirectional impact deviation of nozzle row 33K is (A1, A2), and the reference nozzle region for the bidirectional impact deviation of nozzle row 33M is (A5, A6). Therefore, the offset value for nozzle row 33K is "-0.5", and the offset value for nozzle row 33M is "-2". Figure 13(e) shows the adjustment values ​​after offsetting for each nozzle region of nozzle rows 33K and 33M. The values ​​shown in the table in Figure 13(e) are the second adjustment values ​​P2.

[0095] Furthermore, the third adjustment value is determined for all nozzle rows and all nozzle regions based on the impact position in a specific scanning direction of a reference nozzle region in a particular reference row. In this embodiment, the third adjustment value is determined for all nozzle rows and all nozzle regions using the forward recording of the nozzle regions (A1, A2) of nozzle row 33K as the reference condition. In other words, by using the forward direction of the nozzle regions (A1, A2) of nozzle row 33K as the reference condition and as the basis for discharge timing control, the third adjustment value is determined as an adjustment value to correct the discharge timing so that there is no deviation in the impact position of other conditions (conditions with different nozzle rows, nozzle regions, and recording directions) relative to the impact position of the reference condition.

[0096] When calculating the third adjustment value in equations (3) and (4), if there is a difference in the second adjustment value between the nozzle region where the first adjustment value was obtained and the nozzle region under the reference conditions, a deviation from the appropriate adjustment value will occur. To correct this deviation, the offset value P2 of each nozzle row is used. offset This is determined. Specifically, for nozzle row 33K, the reference nozzle area (A1, A2) of the bidirectional registration adjustment value matches the nozzle row and nozzle area of ​​the reference condition, and since it is not subject to adjustment for intercolor adjustment, there is no offset, i.e., P2 of nozzle row 33K offsetIt is 0. For the nozzle row 33M, the deviation correction of K ink between the K-M color gradation adjustment nozzle regions (A13, A14) and the nozzle region (A1, A2) under the reference conditions (0 - 2 = -2), and the deviation correction of M ink between the reference nozzle regions (A5, A6) in the M bidirectional direction and the reference nozzle regions (A13, A14) between the K-M colors (4 - 0 = 4) are added together, and the resulting value is P2 of the nozzle row 33M offset That is, P2 of the nozzle row 33M offset = 4 + (-2) = 2

[0097] From the first adjustment value P1 shown in FIG. 13(b), the second adjustment value P2 shown in FIG. 13(e), and the offset value P2 offset the third adjustment value P3 is determined. FIG. 13(f) is a table showing a list of adjustment values used in the calculation for determining the third adjustment value P3. In the inter-color registration adjustment (P1 inter-color), with the nozzle row 33K as the reference, since the other nozzle rows including the nozzle row 33M are the adjustment targets, it is not added to the third adjustment value of the nozzle row 33K, but added to the adjustment values of the nozzle rows of the other ink colors including the nozzle row 33M. Also, in the bidirectional registration adjustment (P2 bidirectional), with the forward-direction recording as the reference and the reverse-direction recording as the adjustment target, it is added only to the third adjustment value in the reverse direction. Also, the second adjustment value (P2, and, P2 offset ) is the adjustment target in both the forward and reverse directions, so it is added to the third adjustment values in both directions. However, the second adjustment value (P2) in the forward direction is added after reversing the sign. This is because the direction of shifting the adjustment value in the forward direction is managed as +

[0098] FIG. 13(g) is a table showing the determined third adjustment value P3. When determining the third adjustment value in the forward direction of the nozzle row 33K, as shown in the table of FIG. 13(f), reverse the sign of P2 and add P2 offset (= 0) of the nozzle row 33K. The adjustment values of P1 inter-color and P1 bidirectional are excluded from the calculation target because they are not the adjustment targets

[0099] From the above formula (3) (forward direction: P3 = P1 - P2 + P2 offset ), P3(A1, A2) = 0 - 0 + 0 = 0 P3(A3,A4) = 0 - 0 + 0 = 0 P3(A5,A6) = 0 - 0 + 0 = 0 P3(A7,A8) = 0 - 1 + 0 = -1 P3(A9,A10) = 0 - 1 + 0 = -1 P3(A11,A12) = 0 - 1 + 0 = -1 P3(A13,A14) = 0 - 2 + 0 = -2 P3(A15,A16) = 0 - 2 + 0 = -2 P3(A17,A18) = 0 - 2 + 0 = -2.

[0100] When determining the third adjustment value for the nozzle row 33K in the return direction, the adjustment value for both directions of P1 and the P2 of the nozzle row 33K and the P2 of the nozzle row 33K offset (=0) is added. The adjustment value between P1 colors is excluded from the calculation because it is not subject to adjustment.

[0101] The above equation (4) (reverse direction: P3 = P1 + P2 + P2 offset )twist, P3(A1,A2) = 1 + 0 + 0 = 1 P3(A3,A4) = 1 + 0 + 0 = 1 P3(A5,A6) = 1 + 0 + 0 = 1 P3(A7,A8) = 1 + 1 + 0 = 2 P3(A9,A10) = 1 + 1 + 0 = 2 P3(A11,A12) = 1 + 1 + 0 = 2 P3(A13,A14) = 1 + 2 + 0 = 3 P3(A15,A16) = 1 + 2 + 0 = 3 P3(A17,A18) = 1 + 2 + 0 = 3.

[0102] When determining the third adjustment value in the forward direction of the nozzle row 33M, as shown in the table in Figure 13(f), the P1 color interval, the P2 with the sign reversed, and the P2 of the nozzle row 33M offset (=2) is added. The P1 bidirectional adjustment value is excluded from the calculation because it is not subject to adjustment.

[0103] Equation (3) above (Forward direction: P3=P1-P2+P2offset )twist, P3(A1,A2) = -8 - (-2) + 2 = -4 P3(A3,A4) = -8 - (-1) + 2 = -5 P3(A5,A6) = -8 - 0 + 2 = -6 P3(A7,A8) = -8 - 1 + 2 = -7 P3(A9,A10) = -8 - 2 + 2 = -8 P3(A11,A12) = -8 - 3 + 2 = -9 P3(A13,A14) = -8 - 4 + 2 = -10 P3(A15,A16) = -8 - 5 + 2 = -11 P3(A17,A18) = -8 - 6 + 2 = -12.

[0104] When determining the third adjustment value for the reversal direction of nozzle row 33M, P1 is between colors, P1 is bidirectional, and P2 of nozzle row 33M and P2 of nozzle row 33M. offset Add (=4).

[0105] The above equation (4) (reverse direction: P3 = P1 + P2 + P2 offset )twist, P3(A1,A2) = -8 + 4 + (-2) + 2 = -4 P3(A3,A4) = -8 + 4 + (-1) + 2 = -3 P3(A5,A6) = -8 + 4 + (0) + 2 = -2 P3(A7,A8) = -8 + 4 + 1 + 2 = -1 P3(A9,A10) = -8 + 4 + 2 + 2 = 0 P3(A11,A12) = -8 + 4 + 3 + 2 = 1 P3(A13,A14) = -8 + 4 + 4 + 2 = 2 P3(A15,A16) = -8 + 4 + 5 + 2 = 3 P3(A17,A18) = -8 + 4 + 6 + 2 = 4.

[0106] Although Figure 13 shows specific examples for nozzle rows 33K and 33M, the same procedure and calculation formula can be used for other nozzle rows to obtain the third adjustment value for each nozzle region in the forward and reverse directions, using the forward recording of the nozzle region (A1, A2) of nozzle row 33K as the reference condition.

[0107] The ejection timing correction unit 704 corrects the ink ejection timing of each nozzle area based on a third adjustment value corresponding to the nozzle area, according to the recording mode acquired by the recording mode acquisition unit 700. Specifically, the ejection timing correction unit 704 identifies the nozzle area used in the acquired recording mode and corrects the ink ejection timing of the identified nozzle area based on a third adjustment value corresponding to that nozzle area. The ejection timing correction unit 704 corrects the ejection timing by correcting each nozzle area and predetermined ejection timing specified values ​​(ejection timing specified values ​​when no register adjustment is performed) that are set in advance based on the third adjustment values ​​stored in advance in the memory 405. In the image recording process, the CPU 401 controls the timing of ink ejection according to the recorded data. The correction of the ejection timing according to the recording mode will be described later. The nozzle areas used in the recording mode are predetermined, as shown in Figure 6(b).

[0108] Next, the recording process flow with the third adjustment value applied will be explained. Figure 14 is a flowchart of the recording process flow in this embodiment. Unless otherwise specified, each step of this flowchart is executed by the CPU 401 of the control unit 400 of the recording device 100. When image data is transmitted from the host device 414 and the control unit 400 of the recording device 100 receives the image data via the interface circuit 413, the CPU 401 starts this flowchart. Furthermore, it is assumed that the adjustment value acquisition process shown in Figure 9 is executed before the start of this flowchart, and that the first adjustment value and the second adjustment value are stored in the RAM 403. However, it is assumed that the carriage movement speed when acquiring the adjustment value and the carriage movement speed when executing the recording process are the same.

[0109] In S1401, the CPU 401 acquires image data from the host device 414. At this time, it receives recording mode specification information along with the image data.

[0110] In S1402, CPU401 obtains the first adjustment value P1 (P bidirectional, P between colors) from RAM403. Also in S1403, CPU401 obtains the second adjustment value (P2, P2 offset ) obtain.

[0111] In S1404, the CPU 401 determines a third adjustment value P3 to adjust the ejection timing for each nozzle area of ​​each ink color, based on the acquired first and second adjustment values. The method for determining the third adjustment value is the same as that described in Figures 12 and 13 above. The CPU 401 stores the determined third adjustment value in the RAM 403.

[0112] In S1405, the CPU 401 converts the image data received in S1401 into recording data and outputs it to the recording head 109. At this time, the CPU 401 corrects the ink ejection timing of the nozzle area used in the specified recording mode based on the third adjustment value corresponding to that nozzle area.

[0113] In S1406, the CPU 401 causes the carriage unit 102 to reciprocate in the main scanning direction while ejecting ink from each nozzle of the recording head 109 according to the recorded data with corrected ejection timing. The CPU 401 also controls the transport of the recording medium P and the scanning of the carriage unit 102 to occur alternately. As a result, an image is recorded on the recording medium P. The recorded image is dried and fixed in the image fixing unit, completing the recording process shown in this flowchart.

[0114] Figure 15 shows the relationship between the nozzle area of ​​each nozzle row used for recording in each recording mode and a third adjustment value applied to correct the ejection timing. Figure 15(a) shows the OF mode of the two-layer recording mode, Figure 15(b) shows the UF mode of the two-layer recording mode, and Figure 15(a) shows the SW mode, which is the three-layer recording mode.

[0115] As shown in Figure 15(a), in OF mode, nozzle areas 1501 from A1 to A10 of nozzle rows 33K, 33C, 33M, and 33Y are used for recording, while A11 to A18 are not. In nozzle row 33W, A1 to A10 are not used for recording, and nozzle area 1502 from A11 to A18 is used for recording. Hereinafter, the nozzle areas used for recording will be referred to as the used nozzle areas. In Figure 15(a), the used nozzle areas 1501 and 1502 are shown in gray, and the unused nozzle areas are shown in white.

[0116] The CPU 401 (discharge timing correction unit 704) corrects the discharge timing for forward recording and reverse recording for each nozzle area 1501 and 1502 based on the corresponding third adjustment value. Specifically, for example, for nozzle row 33K, the discharge timing for reverse recording in the nozzle area (A1, A2) is corrected based on the third adjustment value (3_K1_B), using the discharge timing for forward recording in the same area (A1, A2) as a reference. Also, the discharge timing for forward recording in nozzle area (A3, A4) is corrected based on the third adjustment value (3_K2_F), and the discharge timing for reverse recording is corrected based on the third adjustment value (3_K2_B). Furthermore, the discharge timing for forward recording in nozzle area (A5, A6) is corrected based on the third adjustment value (3_K3_F), and the discharge timing for reverse recording is corrected based on the third adjustment value (3_K3_B). Furthermore, the ejection timing for forward recording in nozzle regions (A7, A8) is corrected based on the third adjustment value (3_K4_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_K4_B). Also, the ejection timing for forward recording in nozzle regions (A9, A10) is corrected based on the third adjustment value (3_K5_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_K5_B).

[0117] For C, M, and Y inks, the ejection timing for forward recording and return recording in the nozzle area 1501 is corrected based on a third adjustment value corresponding to each nozzle area.

[0118] For W ink (nozzle row 33W), the ejection timing for forward recording in nozzle area (A11, A12) is corrected based on the third adjustment value (3_W6_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_W6_B). In addition, the ejection timing for forward recording in nozzle area (A13, A14) is corrected based on the third adjustment value (3_W7_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_W7_B). The ejection timing for forward recording in nozzle area (A15, A16) is corrected based on the third adjustment value (3_W8_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_W8_B). The ejection timing for forward recording in the nozzle region (A17, A18) is corrected based on the third adjustment value (3_W9_F), and the ejection timing for return recording is corrected based on the third adjustment value (3_W9_B).

[0119] The relationship between the nozzle regions used in UF mode and the third adjustment values ​​applied to correct the discharge timing is shown in Figure 15(b). As shown in Figure 15(b), the CPU 401 (discharge timing correction unit 704) acquires the third adjustment values ​​for the nozzle regions 1503 and 1504 used, which are determined in recording mode. The nozzle regions used are the nozzle regions 2201 from A11 to A18 of nozzle rows 33K, 33C, 33M, and 33Y, and A1 to A10 of nozzle row 33W. In forward recording of nozzle row 33K, the third adjustment values ​​(3_K6_F) to (3_K9_F) are applied to the corresponding nozzle regions, and in reverse recording, the third adjustment values ​​(3_K6_B) to (3_K9_B) are applied to correct the discharge timing.

[0120] For C, M, and Y inks, the ejection timing for forward recording and return recording in the nozzle area 1503 is corrected based on a third adjustment value corresponding to each nozzle area.

[0121] For nozzle row 33W, the third adjustment values ​​(3_W1_F) to (3_W5_F) are applied to the corresponding nozzle area during forward recording, and the third adjustment values ​​(3_W1_B) to (3_W5_B) are applied during return recording, thereby correcting the discharge timing.

[0122] The relationship between the nozzle regions used in SW mode and the third adjustment value applied to correct the discharge timing is shown in Figure 15(c). As shown in Figure 15(c), the CPU 401 (discharge timing correction unit 704) acquires the third adjustment values ​​for the nozzle regions 1505, 1506, and 1507 used, which are determined in recording mode. Nozzle regions 1505 and 1507 of nozzle rows 33K, 33C, 33M, and 33Y (A1-A6 and A13-A18) and nozzle row 33W (A7-A12) constitute nozzle region 1506. In the forward recording of nozzle row 33K, the third adjustment values ​​(3_K2_F)~(3_K3_F) and (3_K7_F)~(3_K9_F) are applied to the corresponding nozzle regions, and in the return recording, the third adjustment values ​​(3_K2_B)~(3_K3_B) and (3_K7_B)~(3_K9_B) are applied to the corresponding nozzle regions to correct the discharge timing.

[0123] For C, M, and Y inks, the ejection timing for forward recording and return recording in the nozzle areas 1505 and 1507, respectively, are corrected based on a third adjustment value corresponding to each nozzle area.

[0124] For nozzle row 33W, the third adjustment values ​​(3_W4_F) to (3_W6_F) are applied to the corresponding nozzle area during forward recording, and the third adjustment values ​​(3_W4_B) to (3_W6_B) are applied during return recording, thereby correcting the discharge timing.

[0125] As described above, according to the recording device 100 of this embodiment, the bidirectional registration adjustment value and the inter-color registration adjustment value acquired based on a predetermined nozzle area of ​​a predetermined nozzle row are appropriately corrected even when there is a large difference in the ejection speed of each nozzle in the nozzle row. Therefore, it becomes possible to record images with reduced impact misalignment. In particular, even in a recording device 100 that has multiple recording modes and where the usage frequency of each nozzle area differs greatly depending on the usage frequency of the recording modes, it becomes possible to appropriately perform bidirectional and inter-color registration adjustments, thereby reducing impact misalignment.

[0126] In this embodiment, bidirectional recording is performed during the recording process, and the control unit 400 calculates a third adjustment value for both the forward and return directions. However, this embodiment is not limited to this example and can also be applied to unidirectional recording in the forward direction only. In this case, each adjustment value only needs to be acquired and determined for one direction.

[0127] [Modified version of the first embodiment] In the first embodiment, when acquiring the second adjustment value, the adjustment pattern was recorded on the recording medium P, and the amount of impact deviation was detected based on the density of the recorded pattern. At that time, the control unit 400 acquired the density using the optical sensor 410. In the second embodiment, an example is described in which the adjustment value is acquired by directly detecting the ejection speed of the ink droplets ejected from each nozzle, without recording the adjustment pattern.

[0128] (Control configuration of the recording device) Figure 16 is a block diagram showing the control configuration of a modified recording device 100 according to the first embodiment. The difference from the recording device 100 in the first embodiment is the presence of a droplet detection sensor 1601. The configuration of other parts is the same as in the first embodiment. The functional configuration is also the same as shown in Figure 7. However, the second adjustment value acquisition unit 702 determines the second adjustment value using the droplet detection sensor 1601. The first adjustment value acquisition unit 701 acquires the first adjustment value in the same way as in the first embodiment. That is, the first adjustment value acquisition unit 701 records the adjustment pattern and reads it using the optical sensor 410 to acquire the bidirectional impact misalignment of the nozzle row and the impact misalignment between nozzle rows (between colors), and determines the first adjustment value.

[0129] (Droplet detection sensor) The configuration and operation of the droplet detection sensor 1601 will be described with reference to Figure 17. Figure 17(a) is a diagram showing the schematic configuration of the droplet detection sensor 1601 and an overview of the discharge speed detection. Figure 17(b) is a timing chart showing the discharge timing and droplet detection timing based on recorded data. In Figure 17(a), the left-right direction is the Y direction (transport direction of the recording medium P), the up-down direction of the figure is the Z direction (gravity direction), and the direction perpendicular to the plane of the paper is the X direction (carriage movement direction). The droplet detection sensor 1601 is positioned between the platen 104 and a recovery unit (not shown). The droplet detection sensor 1601 is installed so that the optical axis of the light 1740 is in the same position in the Z direction as the surface of the platen 104 that supports the recording medium P.

[0130] The droplet detection sensor 1601 has a light-emitting unit 1710, which is made of a light-emitting element such as an LED, and a light-receiving unit 1720, which is made of a light-receiving element such as a photodiode, and the light-emitting unit 1710 and the light-receiving unit 1720 are arranged to face each other. An ink droplet ejected from the nozzle passes between the light-emitting unit 1710 and the light-receiving unit 1720.

[0131] The CPU 401 ejects ink droplets from each nozzle of the recording head 109 according to the ejection signal based on the recorded data. When the ejected ink droplet passes through the light 1740 emitted from the light-emitting unit 1710, the amount of light received by the light-receiving unit 1720 decreases. If the amount of light received is less than a predetermined threshold, a detection signal is output from the droplet detection sensor 1601 and input to the CPU 401. As shown in Figure 17(b), the time from when the CPU 401 emits the ejection signal until it detects the detection signal is defined as the detection time T1. The CPU 401 determines the ejection speed from the distance H1 from the nozzle to the detection position and the detection time T1. The distance H1 is a known value.

[0132] Next, the acquisition of the second adjustment value using the droplet detection sensor 1601 will be explained in detail. Figure 18 is a flowchart showing the flow of the second adjustment value acquisition process in this modified example. In the process shown in this flowchart, a program stored in the ROM 402 of the control unit 400 of the recording device 100 is called by the CPU 401, loaded into the RAM 403, and executed by the CPU 401. When the CPU 401 receives a processing start instruction based on user operation from the operation panel 105, it starts this process.

[0133] In S1801, the CPU 401 obtains the ejection speed of each nozzle area from the droplet detection sensor 1601. As described above, the ejection speed of the ink droplet is calculated from the detection time T1 from when the CPU 401 outputs the ejection signal until the detection signal output from the droplet detection sensor 1601 is obtained, and the distance H1 from the nozzle to the detection position.

[0134] Figure 19 shows the measured ejection speed and an example of calculating a specific second adjustment value for nozzle row 33W. The CPU 401 calculates the ejection speed V by dividing the detection time T1 detected by the droplet detection sensor 1601 by the distance H1 from the nozzle to the detection position. For example, if the detection time T1 for the nozzle area (A9, A10) is 0.150 [msec], and the distance H1 is 2 [mm], the ink ejection speed V in the nozzle area (A9, A10) is approximately 13.33 [m / s].

[0135] In S1802, CPU401 determines the impact time for each nozzle area. Impact time is the time from when the ink is ejected until it hits the recording medium P. Assuming that the distance H2 between the nozzle and the recording medium P is 1.5 [mm], the impact time in the nozzle areas (A9, A10) is calculated to be 0.1125 [msec].

[0136] In S1803, the CPU 401 uses the nozzle region where the bidirectional impact deviation of the first adjustment value was detected as the reference nozzle region, and determines the second adjustment value of the target nozzle region from the impact time difference between the reference nozzle region and the target nozzle region. In the example in Figure 19, the reference nozzle region is (A9, A10). The impact deviation is determined from the following equations (5) to (7).

[0137] Impact deviation = Impact time difference × Carriage movement speed ... (5) Impact time difference = Impact time of target nozzle - Impact time of reference nozzle ... (6) Impact time = Distance between nozzle and recording medium H2 / Discharge rate V...(7)

[0138] The difference in impact time between the nozzle regions (A1, A2) is -0.015 [msec], and the impact deviation is calculated to be -22.9 [μm].

[0139] The difference in impact time between the nozzle regions (A3, A4) is -0.0075 [msec], and the impact deviation is calculated to be -11.4 [μm].

[0140] The point of impact deviation in nozzle regions (A5, A6) and (A7, A8) is 0.

[0141] The difference in impact time between nozzle regions (A11, A12) and (A13, A14) is 0.0075 [msec], and the impact deviation is +11.4 [μm].

[0142] The difference in impact time between nozzle regions (A15, A16) and (A17, A18) is 0.015 [msec], and the impact deviation is +22.9 [μm].

[0143] If we consider the time equivalent to a 5 [μm] correction as one unit, the second adjustment value will be "5" in the nozzle region (A1, A2), "2" in the nozzle region (A2, A3), "0" in the nozzle region (A5, A6) to (A9, A10), "-2" in the nozzle region (A11, A12) to (A13, A14), and "-5" in the nozzle region (A15, A16) to (A17, A18).

[0144] Thus, the second adjustment value can also be determined by measuring the ink droplet ejection speed using the droplet detection sensor 1601. The third adjustment value can be determined based on the first and second adjustment values, similar to the first embodiment.

[0145] [Modification 2 of the First Embodiment] In the first embodiment, the explanation was based on the assumption that the carriage movement speed is the same in all recording modes. However, the carriage movement speed may differ depending on the recording mode. For example, the carriage movement speed in single-layer recording mode is predetermined as V1, the carriage movement speed in two-layer recording mode as V2, and the carriage movement speed in three-layer recording mode as V3. When the carriage movement speed differs, the amount of deviation in the recording position also changes. In the modified example 2, the CPU 401 determines a first adjustment value, a second adjustment value, and a third adjustment value for each recording mode, i.e., for each carriage movement speed, and corrects the discharge timing of the nozzle area used with the third adjustment value corresponding to the recording mode.

[0146] The first adjustment value acquisition unit 701 identifies the carriage movement speed set for each recording mode, records the adjustment pattern at the identified carriage movement speed, and acquires the first adjustment value. Similarly, the second adjustment value acquisition unit 702 acquires the second adjustment value at the identified carriage movement speed. The second adjustment value may be acquired from the adjustment pattern, or, as shown in Modification 1, may be acquired based on the ink ejection speed measured by the droplet detection sensor 1601. The third adjustment value determination unit 703 acquires the first and second adjustment values ​​according to the recording mode, and determines the third adjustment value based on the acquired first and second adjustment values. The determined third adjustment value is stored in the RAM 403 in association with the recording mode or carriage movement speed.

[0147] During the recording process, the CPU 401 converts the image data received from the host device 414 into recording data and outputs it to the recording head 109. At this time, the CPU 401 obtains a third adjustment value associated with the specified recording mode from the RAM 403. The CPU 401 also obtains the nozzle area used in the recording mode (Figure 15). The CPU 401 corrects the ink ejection timing of each nozzle area used in the recording mode based on the obtained third adjustment value.

[0148] The CPU 401 causes the carriage unit 102 to reciprocate in the main scanning direction at a recording speed corresponding to the recording mode, while simultaneously ejecting ink from each nozzle of the recording head 109 according to the recording data with corrected ejection timing. The CPU 401 also controls the alternating transport of the recording medium and the scanning of the carriage. As a result, an image is recorded on the recording medium P.

[0149] As explained above, even when different carriage movement speeds are set depending on the recording mode, the method of this modified example 2 makes it possible to appropriately correct the discharge timing for each nozzle region.

[0150] In the above explanation, an example was shown in which the CPU 401 acquires a first adjustment value and a second adjustment value for each recording mode and stores the first and second adjustment values ​​in the RAM 403 in association with the recording mode or the carriage movement speed used in the recording mode, but the CPU 401 is not limited to this. The CPU 401 may also store the first adjustment values ​​(P1_V1), (P1_V2), (P1_V3), ... and the second adjustment values ​​(P2_V1), (P2_V2), (P2_V3), ... acquired at multiple different carriage movement speeds V1, V2, V3, ... in the RAM 403 in association with the carriage movement speeds V1, V2, V3, ... respectively. In that case, the CPU 401 may, at the stage when the recording mode is specified in the recording process, acquire the first and second adjustment values ​​from the RAM 403 that are associated with the carriage movement speed corresponding to the recording mode and determine the third adjustment value.

[0151] Alternatively, the CPU 401 may pre-determine third adjustment values ​​(P3_V1), (P3_V2), (P3_V3), ... for multiple different carriage movement speeds V1, V2, V3, ... as a pre-processing step, and store them in RAM 403 in association with the carriage movement speeds. In this case, when the recording mode is specified during the recording process, the CPU 401 only needs to retrieve the third adjustment value corresponding to the carriage movement speed according to the recording mode from RAM 403. Furthermore, if the RAM 403 does not store the first, second, or third adjustment values ​​corresponding to the carriage movement speed used in the recording mode, the CPU 401 may retrieve the first, second, or third adjustment value from RAM 403 that is associated with the carriage movement speed closest to the carriage movement speed used in the recording mode. Even with these methods, it is possible to appropriately correct the discharge timing for each nozzle region, even when different carriage movement speeds are set depending on the recording mode.

[0152] [Second Embodiment] In the first embodiment, an example was shown in which a third adjustment value was determined for each nozzle region of each nozzle row, and the discharge timing was adjusted for each nozzle region of each nozzle row based on the determined third adjustment value. In the second embodiment, as a simpler configuration, an example is described in which the discharge timing is corrected on a nozzle row basis based on the third adjustment value of the nozzle region used in recording mode. Note that the hardware configuration and control configuration of the recording device 100 in the second embodiment are the same as in the first embodiment, so the description is omitted, and the same parts as in the first embodiment are denoted by the same reference numerals. The following description will focus on the differences from the first embodiment.

[0153] (Functional Configuration) Figure 20 is a block diagram showing the functional configuration of the recording device 100 in the second embodiment. As shown in Figure 20, in the second embodiment, the control unit 400A includes a recording mode acquisition unit 700, a first adjustment value acquisition unit 701, a second adjustment value acquisition unit 702, a third adjustment value determination unit 703, a correction value determination unit 2001, and an ejection timing correction unit 2002. The differences from the functional configuration of the first embodiment are the addition of the correction value determination unit 2001 and the fact that the ejection timing correction unit 2002 corrects the ejection timing on a nozzle row basis. In the second embodiment, each of these functional units is realized by the CPU 401A calling a program stored in the non-volatile storage area of ​​the ROM 402 or RAM 403 and executing processing according to the program.

[0154] The correction value determination unit 2001 determines an ejection timing correction value (hereinafter referred to as the correction value) to be applied to the entire nozzle row from the third adjustment value of each nozzle area used in the recording mode. Figure 21 is a diagram illustrating the ejection timing correction in the second embodiment. Figure 21(a) is a diagram showing the nozzle areas used in the recording mode and the assignment of the third adjustment value. As an example, the case of OF mode is shown. In OF mode, nozzle areas 2101 from A1 to A10 of nozzle rows 33K, 33C, 33M, and 33Y are used for recording, and A11 to A18 are not used for recording. In nozzle row 33W, A1 to A10 are not used for recording, and nozzle area 2102 from A11 to A18 is used for recording. In Figure 21(a), the used nozzle areas 2101 and 2102 are shown in gray, and the unused nozzle areas are shown in white. In this way, in stacked recording, the used nozzle areas of the entire nozzle row are limited to a portion of the total nozzle area. In this case, while using the same recording mode continuously, the difference in ejection speed between each nozzle within the nozzle area is smaller compared to when switching to a different recording mode and the nozzle area changes, and the impact deviation is also relatively small.

[0155] Therefore, the correction value determination unit 2001 determines an ejection timing correction value (hereinafter referred to as the correction value) to be applied to the entire nozzle row from the third adjustment value of each nozzle region used in the recording mode. For example, as shown in Figure 21(a), the nozzle regions 2102 (A11~A18) used in the nozzle row 33W are assigned (3_W6_F), (3_W7_F), (3_W8_F), (3_W9_F) as third adjustment values ​​for forward scanning, and (3_W6_B), (3_W7_B), (3_W8_B), (3_W9_B) as third adjustment values ​​for reverse scanning. As described above, in this recording mode, it is assumed that the impact deviation between nozzle regions is relatively small within the nozzle regions A11~A18 used.

[0156] Therefore, the correction value determination unit 2001 calculates a correction value from the third adjustment values ​​(3_W6_F), (3_W7_F), (3_W8_F), and (3_W9_F) in the forward direction of the nozzle area being used, and sets the calculated correction value as the third adjustment value (3_W_F) for forward scanning of the entire nozzle row 33W. Similarly for the return direction, the correction value determination unit 2001 calculates a correction value from the third adjustment values ​​(3_W6_B), (3_W7_B), (3_W8_B), and (3_W9_B) in the return direction of the nozzle area being used, and sets the calculated correction value as the third adjustment value (3_W_B) for return scanning of the entire nozzle row 33W. The correction value is the average value of each third adjustment value in the nozzle area being used. Note that the correction value is not limited to the average value, but may also be a value that can be determined from the third adjustment values ​​in the forward and return directions in the nozzle area being used, such as the maximum or minimum value.

[0157] Figure 21(b) shows the correction values ​​determined in the third embodiment. As described above, the correction value determination unit 2001 acquires the third adjustment value for the nozzle area used, which is determined in the recording mode, and determines the correction value for the discharge timing on a nozzle row basis. The correction value determination unit 2001 determines the correction value for both forward and reverse scanning of all nozzle rows. The third adjustment value is determined in the same manner as in the first embodiment. Alternatively, the third adjustment value may be determined only for the nozzle area used corresponding to the recording mode. Furthermore, a predetermined third adjustment value may be acquired from the RAM 403 based on the recording mode.

[0158] In the example shown in Figure 21(b), the correction value for each nozzle row is based on the discharge timing of the forward scanning of nozzle row 33K. However, in the forward scanning of nozzle row 33K, the average value of the third adjustment value (reference: equivalent to 0), (3_K2_F), (3_K3_F), (3_K4_F), and (3_K5_F) within the nozzle area 2101 used (P4 offset ) minutes. The center of the impact point shifts from the impact point in the reference nozzle area (A1, A2). Therefore, for other adjustment values, P4 offset It is preferable to offset the adjustment value by only that amount.

[0159] Correction values ​​for the discharge timing in the forward and reverse directions of each nozzle row are determined with respect to the forward scanning of the reference nozzle row 33K. Specifically, the correction value (3_K_B) in the reverse scanning of the nozzle row 33K is calculated by taking, for example, the average value of the third adjustment values ​​(3_K1_B), (3_K2_B), (3_K3_B), (3_K4_B), and (3_K5_B) within the nozzle area 2101 used, and applying P4 offset It will be the value offset by that amount.

[0160] The correction value (3_C_F) for forward scanning of nozzle row 33C is, for example, the average of the third adjustment values ​​(3_C1_F), (3_C2_F), (3_C3_F), (3_C4_F), and (3_C5_F) within the nozzle area 2101 used. Furthermore, the correction value (3_C_B) for reverse scanning of nozzle row 33C is, for example, the average of the third adjustment values ​​(3_C1_B), (3_C2_B), (3_C3_B), (3_C4_B), and (3_C5_B) within the nozzle area 2101 used, with respect to P4 offset It will be the value offset by that amount.

[0161] The correction value (3_M_F) for forward scanning of nozzle row 33M is, for example, the average of the third adjustment values ​​(3_M1_F), (3_M2_F), (3_M3_F), (3_M4_F), and (3_M5_F) within the nozzle area 2101 used. Furthermore, the correction value (3_M_B) for reverse scanning of nozzle row 33C is, for example, the average of the third adjustment values ​​(3_M1_B), (3_M2_B), (3_M3_B), (3_M4_B), and (3_M5_B) within the nozzle area 2101 used, with respect to P4 offset It will be the value offset by that amount.

[0162] The correction value (3_Y_F) for forward scanning of nozzle row 33Y is, for example, the average of the third adjustment values ​​(3_Y1_F), (3_Y2_F), (3_Y3_F), (3_Y4_F), and (3_Y5_F) within the nozzle area 2101 used. Similarly, the correction value (3_M_B) for reverse scanning of nozzle row 33C is, for example, the average of the third adjustment values ​​(3_Y1_B), (3_Y2_B), (3_Y3_B9), (3_Y4_B), and (3_Y5_B) within the nozzle area 2101 used.

[0163] The correction value (3_W_F) for forward scanning of nozzle row 33W is, as described above, the average of the third adjustment values ​​(3_W6_F), (3_W7_F), (3_W8_F), and (3_W9_F) within the nozzle area 2102 used. Furthermore, the correction value (3_W_B) for reverse scanning of nozzle row 33W is, for example, the average of the third adjustment values ​​(3_W6_B), (3_W7_B), (3_W8_B), and (3_W9_B) within the nozzle area 2102 used, with respect to P4 offset It will be the value offset by that amount.

[0164] The same applies to recording modes other than OF mode. The correction value determination unit 2001 determines the discharge timing correction value in the forward direction based on the third adjustment value in the forward direction determined for the nozzle area used in the recording mode. The correction value determination unit 2001 also determines the discharge timing correction value in the return direction based on the third adjustment value in the return direction determined for the nozzle area used in the recording mode. The nozzle area used and the third adjustment value for each recording mode are the same as in Figure 15.

[0165] The ejection timing correction unit 2002 corrects the ink ejection timing for each nozzle row based on the correction value determined by the correction value determination unit 2001.

[0166] As described above, in the second embodiment, the control unit 400 of the recording device 100 determines the ejection timing correction values ​​for the forward and reverse directions for each nozzle row based on a third adjustment value of the nozzle area used in the recording mode. In this way, even when the ejection timing is corrected on a row-by-row basis, the ejection timing is corrected based on a third adjustment value obtained by correcting a first adjustment value, which includes bidirectional registration adjustment of the nozzle row and registration adjustment between nozzle rows, with a second adjustment value that adjusts the difference in ejection speed within the nozzle row. Therefore, image recording with reduced impact misalignment can be performed. In particular, the ejection timing is preferably corrected when the same recording mode is continued and the nozzle area used is limited. Furthermore, compared to the first embodiment, it becomes possible to more easily correct the ejection timing to reduce the misalignment of the recording position.

[0167] [Modified version of the second embodiment] In the second embodiment, the correction value determination unit 2001 determined the discharge timing correction values ​​for the forward and reverse directions for each nozzle row based on the average value of the third adjustment value assigned to the nozzle area used in recording mode. However, the method for determining the discharge timing correction values ​​is not limited to this, and may be determined based on the usage ratio of the nozzle area used in recording mode.

[0168] Figure 22 shows an example of usage ratios in a nozzle row. The usage ratio of each nozzle area in a nozzle row is determined by the mask pattern used to generate the recorded data. In the mask pattern 2200 shown in Figure 22, the nozzle areas used are set to A1 to A10, and A11 to A18 are set not to be used. The mask pattern 2200 is a so-called gradient mask, where the usage ratio is low at the ends of the nozzle areas used and high in the center of the nozzle areas used. In multi-pass recording, the impact of misalignment of the projectiles in nozzle areas with high usage ratios becomes significant. Therefore, in this modified example, the correction value determination unit 2001 determines the discharge timing correction values ​​for the forward and reverse directions for each nozzle row by weighting based on the nozzle usage ratio, i.e., the frequency of use. The nozzle usage ratio is determined based on the mask pattern 2200 applied to the recording mode, as described above.

[0169] For example, in OF mode, as shown in Figure 21(a) above, nozzle regions 2101 A1 to A10 of nozzle rows 33K, 33C, 33M, and 33Y are used for recording, while A11 to A18 are not used for recording. The mask pattern shown in Figure 22 is applied to these nozzle rows 33K, 33C, 33M, and 33Y.

[0170] As shown in Figure 21(b), correction values ​​for the discharge timing in the forward and reverse directions of each nozzle row are determined based on the discharge timing of the forward scanning of the nozzle row 33K. Specifically, the correction value (3_K_B) for the reverse scanning of the nozzle row 33K is determined based on the third adjustment values ​​(3_K1_B), (3_K2_B), (3_K3_B), (3_K4_B), and (3_K5_B) within the nozzle area 2101 used. In this modified example, the third adjustment values ​​assigned to the nozzle area 2102 are added with weights corresponding to their respective usage ratios. In addition, an offset value P4 corrects the deviation from the impact position of the reference nozzle area. offsetSimilarly, these are calculated by adding them with weights. Specifically, the correction value (3_K_B) in the bidirectional scanning of nozzle row 33K is determined by the following equations (8) and (9). α1 to α5 are weights corresponding to the usage ratio of nozzle regions (A1, A2) to (A9, A10), respectively. Note that in mask pattern 2200, the values ​​of weights α6 to α9 corresponding to (A11, A12) to (A17, A18) are 0.

[0171] (3_K_B)=α1×(3_K1_B)+α2×(3_K2_B)+α3×(3_K3_B)+α4×(3_K4_B)+α5×(3_K5_B)-P4 offset ...(8) P4 offset =α1×0+α2×(3_K2_F)+α3×(3_K3_F)+α4×(3_K4_F)+α5×(3_K5_F)...(9)

[0172] Similarly, for the other rows, the discharge timing correction values ​​for the forward and reverse directions are determined for each nozzle row by assigning weights corresponding to the usage ratio of each nozzle area.

[0173] The ejection timing correction unit 2002 corrects the ink ejection timing for each nozzle row based on the correction value determined by the correction value determination unit 2001.

[0174] As described above, as a modification of the second embodiment, the control unit 400 of the recording device 100 determines the discharge timing correction values ​​for the forward and reverse directions for each nozzle row based on the third adjustment value of the nozzle area used in recording mode and the usage ratio of each nozzle area. This makes it possible to appropriately correct the discharge timing, taking into account the usage frequency of each nozzle, in addition to the effects of the second embodiment.

[0175] Preferred embodiments of the present disclosure have been described above with reference to the attached drawings, but the present disclosure is not limited to such examples. For example, in the embodiments described above, the nozzle region is divided into 18 regions, but the number of divisions of the nozzle region is not limited thereto. It will be obvious to those skilled in the art that various modifications or alterations can be conceived within the scope of the disclosed technical idea, and these will naturally also fall within the technical scope of the present disclosure.

[0176] [Other embodiments] This disclosure can also be implemented by supplying a program that implements one or more of the functions of the embodiments described above to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be implemented by a circuit (e.g., an ASIC) that implements one or more functions.

[0177] The above-described embodiments include the following configurations. (Composition 1) A control device for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which multiple recording elements for applying ink to a recording medium are arranged, is scanned in a first direction, and a transport operation in which the recording medium is transported in a second direction intersecting the first direction, An acquisition means for acquiring a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is reduced, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the array direction, A determination means for determining a third adjustment value for correcting the discharge timing for each region based on the first adjustment value and the second adjustment value, A control device characterized by comprising:

[0178] (Configuration 2) If the recording operation includes forward movement and return movement in the first direction, The control device according to configuration 1, characterized in that the first adjustment value includes an adjustment value for correcting the discrepancy in the recording position in the forward and return directions of the recording operation.

[0179] (Composition 3) The control device according to configuration 1 or configuration 2, characterized in that the first adjustment value includes an adjustment value for correcting the discrepancy between the recording position by a reference recording element array and the recording position by the target recording element array.

[0180] (Composition 4) The control device according to any one of configurations 1 to 3, characterized in that the second adjustment value is an adjustment value obtained for each recording element array based on the difference in recording position between the forward and reverse directions of the recording operation for each region.

[0181] (Composition 5) If the recording operation includes forward movement and return movement in the first direction, The control device according to any one of configurations 1 to 4, characterized in that the determination means determines the third adjustment value for the forward and return directions of the first direction, respectively.

[0182] (Composition 6) The acquisition means further acquires information specifying one of several modes in which the areas used for recording are each different, The control device according to any one of configurations 1 to 5, further comprising a correction means for correcting the ink ejection timing of the region used in the mode specified by the specified information based on the third adjustment value corresponding to the region.

[0183] (Composition 7) The acquisition means further acquires information specifying one of several modes in which the areas used for recording are each different, The control device according to any one of configurations 1 to 5, characterized in that the determination means determines a correction value for the ink ejection timing of each recording element row based on the third adjustment value corresponding to the region used in the mode specified by the designated information.

[0184] (Composition 8) The control device according to configuration 7, further comprising a correction means for correcting the ink ejection timing of the region used in the mode specified by the specified information, based on a correction value for the ink ejection timing determined for each row of recording elements.

[0185] (Composition 9) The control device according to configuration 7, characterized in that the correction value is determined based on the average value of the third adjustment value corresponding to the region used in the mode specified by the specified information.

[0186] (Composition 10) The control device according to configuration 7, characterized in that the correction value is determined based on the usage ratio of the region used in the mode specified by the specified information and the third adjustment value.

[0187] (Composition 11) The control device according to any one of configurations 1 to 10, characterized in that the acquisition means acquires the first adjustment value and the second adjustment value based on optical characteristics read from the adjustment pattern recorded by the forward recording operation and the return recording operation.

[0188] (Composition 12) The control device according to any one of configurations 1 to 10, characterized in that the acquisition means acquires the first adjustment value based on optical characteristics read from an adjustment pattern recorded on a recording medium, and acquires the second adjustment value based on the measurement result of the ink ejection speed ejected from each recording element in each recording element array.

[0189] (Composition 13) A control method for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which multiple recording elements for applying ink to a recording medium are arranged, is scanned in a first direction, and a transport operation in which the recording medium is transported in a second direction intersecting the first direction, The steps include obtaining a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is reduced, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the array direction, A step of determining a third adjustment value for correcting the discharge timing for each region based on the first adjustment value and the second adjustment value, A control method characterized by including

[0190] (Composition 14) A program to cause the computer to function as the control device described in Configuration 1.

Claims

1. A control device for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which a plurality of recording elements for applying ink to a recording medium is arranged, is scanned in a first direction, and a transport operation in which the recording medium is transported in a second direction intersecting the first direction, An acquisition means for acquiring a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is reduced, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the array direction, A determination means for determining a third adjustment value for correcting the discharge timing for each region based on the first adjustment value and the second adjustment value, A control device characterized by comprising:

2. If the recording operation includes forward movement and return movement in the first direction, The control device according to claim 1, characterized in that the first adjustment value includes an adjustment value for correcting the discrepancy in the recording position in the forward and return directions of the recording operation.

3. The control device according to claim 1 or 2, characterized in that the first adjustment value includes an adjustment value for correcting the discrepancy between the recording position by a reference recording element array and the recording position by the target recording element array.

4. The control device according to claim 1, characterized in that the second adjustment value is an adjustment value obtained for each recording element array based on the difference in recording position between the forward and reverse directions of the recording operation for each region.

5. If the recording operation includes forward movement and return movement in the first direction, The control device according to claim 1, characterized in that the determination means determines the third adjustment value for the forward and return directions of the first direction, respectively.

6. The acquisition means further acquires information specifying one of several modes in which the areas used for recording are each different, The control device according to claim 1, further comprising a correction means for correcting the ink ejection timing of the region used in the mode specified by the specified information based on the third adjustment value corresponding to the region.

7. The acquisition means further acquires information specifying one of several modes in which the areas used for recording are each different, The control device according to claim 1, characterized in that the determination means determines a correction value for the ink ejection timing of each recording element row based on the third adjustment value corresponding to the region used in the mode specified by the designated information.

8. The control device according to claim 7, further comprising a correction means for correcting the ink ejection timing of the region used in the mode specified by the specified information based on a correction value for the ink ejection timing determined for each row of recording elements.

9. The control device according to claim 7, characterized in that the correction value is determined based on the average value of the third adjustment value corresponding to the region used in the mode specified by the specified information.

10. The control device according to claim 7, characterized in that the correction value is determined based on the usage ratio of the area used in the mode specified by the specified information and the third adjustment value.

11. The control device according to claim 1, characterized in that the acquisition means acquires the first adjustment value and the second adjustment value based on optical characteristics read from the adjustment pattern recorded by the forward recording operation and the return recording operation.

12. The control device according to claim 1, characterized in that the acquisition means acquires the first adjustment value based on optical characteristics read from an adjustment pattern recorded on a recording medium, and acquires the second adjustment value based on the measurement result of the ink ejection speed ejected from each recording element in each recording element array.

13. A control method for inkjet recording that repeatedly performs a recording operation in which a recording element array, in which multiple recording elements for applying ink to a recording medium are arranged, is scanned in a first direction, and a transport operation in which the recording medium is transported in a second direction intersecting the first direction, The steps include obtaining a first adjustment value for correcting the ink ejection timing in each recording element array so that the deviation of the recording position in the first direction is reduced, and a second adjustment value for correcting the difference in ink ejection speed between regions obtained by dividing each recording element array in the array direction, A step of determining a third adjustment value for correcting the discharge timing for each region based on the first adjustment value and the second adjustment value, A control method characterized by including

14. A program for causing a computer to function as the control device described in claim 1.

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