JP2019034441A - Recording device, recording method, and program - Google Patents

Abstract

To suppress generation of density unevenness on a recording image, when adopting a time-division driving system.SOLUTION: At scanning time in a first direction, a plurality of recording elements are time-division driven following a first order. First recording data for recording an image at the scanning time in the first direction is generated so that a non-formation part where a dot is not formed is included in a first column area and in a second column area. The first order is set so that an average of deviation amounts of a formation position of the dot in the first direction in the first column area becomes approximately equal to an average of deviation amounts of the formation position of the dot in the first direction in the second column area.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a recording apparatus, a recording method, and a program for driving a plurality of recording elements in a recording head in a time-sharing manner.

  Patent Document 1 describes an image processing method in which an output pattern (dot arrangement pattern) corresponding to one multilevel data is made different in order to realize high-resolution output of input image data. On the other hand, the time-division driving method in which a plurality of recording elements in the recording head are time-division driven can reduce the power supply capacity.

JP 7-46522 A

  When the image processing method described in Patent Document 1 is employed for a time-division drive type recording apparatus, the dot arrangement pattern and the order of time-division drive of the recording elements are synchronized, and the recorded image May cause uneven density.

  An object of the present invention is to provide a recording apparatus, a recording method, and a program that can suppress the occurrence of density unevenness in a recorded image when a time-division driving method is employed.

  The recording apparatus of the present invention includes a recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction, and a unit area on the recording medium that scans the recording head in a first direction intersecting the predetermined direction. Scanning means for generating the first recording data corresponding to the image to be recorded when scanning in the first direction, and forming the dots in the unit area in the first direction. And a drive unit that drives the plurality of printing elements in a time-sharing manner in a first order during scanning, wherein the generation unit extends in the predetermined direction and has a different position in the first direction. The first recording data is so formed that non-formed portions where the dots are not formed are formed in different positions in the predetermined direction with respect to the first column region and the second column region on the recording medium positioned at And an average deviation amount of the dot formation positions in the first direction in the first column region and an average deviation amount of the dot formation positions in the first direction in the second column region. And the first order is set so as to be substantially equal to each other.

  According to the present invention, it is possible to suppress the occurrence of density unevenness in a recorded image by optimally setting the driving order of the recording elements in consideration of the positional deviation of the dots related to the driving timing of the recording elements.

It is explanatory drawing of the basic composition of the recording device in the 1st Embodiment of this invention. It is explanatory drawing of the recording head in FIG. FIG. 6 is an explanatory diagram of a relationship among a nozzle row of a recording head, a drive signal, and ink droplets. It is a flowchart for demonstrating the process of the image data in the 1st Embodiment of this invention. It is explanatory drawing of the image data converted by the resolution conversion process in the 1st Embodiment of this invention. It is explanatory drawing of the multipass recording system in the 1st Embodiment of this invention. It is explanatory drawing of the drive timing of the drive block in the 1st Embodiment of this invention, and the formation position of a dot. It is the one part enlarged view of FIG.7 (c). It is a flowchart for demonstrating the process of the image data in the 2nd Embodiment of this invention. It is explanatory drawing of the multipass recording system in the 2nd Embodiment of this invention. It is explanatory drawing of the production | generation process of the recording data in the 2nd Embodiment of this invention. It is explanatory drawing of the drive timing of the drive block in the 2nd Embodiment of this invention, and the formation position of a dot. FIG. 13 is an enlarged view of a part of FIG. It is explanatory drawing of the drive timing of the drive block in a comparative example, and the formation position of a dot. It is a one part enlarged view of FIG.14 (c).

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  In this specification, “recording” (sometimes referred to as “printing”) is not limited to the case of forming significant information such as characters and figures, but is not significant. In addition, “recording” means that images, patterns, patterns, etc. are widely formed on recording media, regardless of whether they are manifested so that humans can perceive them visually, or processing of media It also represents the case where “Recording media” is not only paper used in general recording equipment, but also a wide range of materials that can accept ink, such as vinyl, cloth, plastic film, metal plate, glass, ceramics, wood, leather, etc. Is also expressed. Furthermore, “ink” (sometimes referred to as “liquid”) is to be interpreted widely, and is applied on a recording medium to form an image, a pattern, a pattern, etc., and process the recording medium. Or a liquid that can be subjected to ink processing. Further, “recording element” (sometimes referred to as “nozzle”), unless otherwise specified, is a discharge energy generating element that generates energy used for discharging a discharge port, a liquid path communicating therewith, and ink. Will be summarized.

(First embodiment)
1 to 8 are diagrams for explaining the first embodiment of the present invention. First, the basic configuration of the recording apparatus will be described with reference to FIGS. 1 to 5. FIG.

(Basic configuration of recording device)
FIG. 1A is a perspective view for explaining a configuration example of an ink jet recording apparatus (recording apparatus), FIG. 1B is a perspective view of FIG. 1B, and FIG. FIG. 1C is a block diagram of a control system in the recording apparatus.

  The four ink cartridges 101 store cyan (C), magenta (M), yellow (Y), and black (K) ink, respectively, and the recording head 102 ejects these inks toward the recording medium P. Thus, dots can be formed. The conveyance roller 103 and the auxiliary roller 104 convey the white recording medium P in the + Y direction (sub-scanning direction) by rotating in the direction of the arrow in the figure while suppressing the recording medium P. The paper feed roller 105 feeds the recording medium P and plays the role of suppressing the recording paper P, like the transport roller 103 and the auxiliary roller 104. The carriage 106 includes the ink cartridge 101 and the recording head 102 and moves in the ± X direction (main scanning direction) during an image recording operation. The carriage 106 stands by at the position (home position) h of the dotted line in FIG. 1A during a non-recording operation and a recovery operation of the recording head 102. The platen 107 stably supports the recording medium P at the recording position. The carriage belt 108 transmits a moving force that moves the carriage 106 in the ± X directions, and the carriage shaft 109 supports the carriage 106 so as to be movable in the arrows ± X directions.

  In FIG. 1C, the CPU 100 executes control processing of the operation of the recording apparatus, data processing, and the like. The ROM 111 stores programs for executing these processes, and the RAM 112 is used as a work area for executing these processes. When the CPU 100 supplies heater drive data (image data) and a drive control signal (heat pulse signal) to the head driver 102 </ b> A, ink is ejected from the recording head 102. The CPU 100 controls a carriage motor 113 for moving the carriage 106 in the main scanning direction via the motor driver 113A, and a conveyance motor 114 for conveying the recording medium P to + Y via the motor driver 114A. Control.

  In the recording apparatus of this example, the recording head 102 moves in the ± X direction together with the carriage 106 while ejecting ink, and the conveyance of the recording medium P in the + Y direction are alternately repeated to thereby apply the recording medium P to the recording medium P. Record an image.

  FIG. 2A is a plan view of the recording head 102 as viewed from the Z direction, and FIG. 2B is an enlarged view of a discharge port portion of the recording head 102. In the recording head 102, an ejection port array L (Lk, Lc, Lm, Ly) is formed. Black ink is ejected from the ejection port array Lk, cyan ink is ejected from the ejection port array Lc, magenta ink is ejected from the ejection port array Lm, and yellow ink is ejected from the ejection port array Ly. In the discharge port array L, a plurality of discharge ports 201 are arranged as shown in FIG.

  In the ejection port 201 of this example, the amount of ink droplets to be ejected is 2 pl, and 256 are arranged in the Y direction (predetermined direction) at 600 dpi intervals. A discharge energy generating element such as an electrothermal conversion element (heater) or a piezo element is disposed directly below the discharge port 201 (+ Z direction). In the case of this example, a heater is used as the ejection energy generating element, and the ink is foamed by the heat generation, and the ink is ejected from the ejection port 201 using the foaming energy.

  In a recording apparatus using the recording head 102 in which a large number of discharge ports 201 are arranged in this way, as a method for reducing the capacity of the power source, a plurality of heaters corresponding to each of the discharge ports 201 are divided into a plurality of sections (groups). There is a method of time-division driving divided into three). For example, 256 heaters corresponding to each of the discharge ports 201 are divided into 16 groups, and the drive timing is slightly shifted for each group. By such time-division driving, the number of heaters driven simultaneously can be reduced and the capacity of the power supply in the printing apparatus can be kept small.

  FIG. 3 is an explanatory diagram of the relationship between the ejection port array L, the drive signal applied to the heater, and the ink droplets ejected from the ejection port 201. The nozzle includes a discharge port 201, a liquid path communicating with the discharge port 201, and a heater (discharge energy generating element). The number of nozzles in one discharge port array (also referred to as “nozzle array” or “printing element array”) L is 256 corresponding to the discharge ports 201. As will be described later, nozzle numbers 1 to 256 are assigned to the respective nozzles. Is attached. These 256 nozzles are divided into 16 sections of 16 nozzles (from the first section to the 16th section). The 16 nozzles in each section belong to one of 16 drive blocks (from the first block B1 to the 16th block B16), and are time-division driven in units of blocks during the recording operation. Of the 256 nozzles, those belonging to the same drive block are driven simultaneously. More specifically, each nozzle is driven in a time-sharing manner by applying a pulse-like drive signal 301 to each heater in each nozzle. Thereby, the ink droplet 302 is discharged from the discharge port 201 in each nozzle.

  In this example, for 256 nozzles, nozzle number 1 is assigned to the downstream side in the Y direction, and nozzle numbers 2, 3,..., 256 are assigned toward the upstream side in the Y direction. It was attached. Sixteen nozzles with nozzle numbers 1, 2, 3,..., 16 in the first section belong to the first block B1, the second block B2, the third block B3,. Further, the 16 nozzles of nozzle numbers 17, 18, 19,..., 32 in the second section belong to the first block B1, the second block B2, the third block B3,. . The same applies to the nozzles in the other sections, and the 16 nozzles of nozzle numbers 241, 242, 243,..., 256 in the 16th section are the first block B1, the second block B2, the third block B3, respectively. ... belonging to the 16th block B16. When the integer (0 to 15) of the number (16) corresponding to the first to sixteenth sections is “a”, the nozzle with the nozzle number (16 × a + 1) belongs to the first block B1, and the nozzle number is ( 16 × a + 2) nozzles belong to the second block B2. The same applies to nozzles with other nozzle numbers. That is, the nozzle with the nozzle number (16 × a + b) belongs to the b-th block Bb. As described above, the nozzles in each section periodically correspond to the first block B1 to the sixteenth block B16.

  In the example of FIG. 3, the nozzles in each section are in the order of belonging to the blocks B1, B5, B9, B13, B2, B6, B10, B14, B3, B7, B11, B15, B4, B8, B12, B16. Driven. The driving order of the blocks B1 to B16 is stored in the ROM 111 (FIG. 1C) in the recording apparatus, and the heater outputs a block selection signal output at a predetermined interval according to the driving order, and recording. It is driven based on a drive signal corresponding to the logical product of data and data.

(Characteristic configuration)
Next, a characteristic configuration of the first embodiment of the present invention will be described with reference to FIGS.

  FIG. 4 is a flowchart for explaining the process of processing the image data.

  First, RGB original image signals of 256 gradations (0 to 255) are input at a resolution of 600 dpi from an image input device such as a digital camera or a scanner, or a computer (step S1). The RGB original image signal is converted into an R′G′B ′ signal by color conversion processing A (step S2), and the R′G′B ′ signal is a signal value corresponding to each color ink by color conversion processing B. (Step S3). In this example, the data is converted into data C1, M1, Y1, and K1 corresponding to inks of four colors of C (cyan), M (magenta), Y (yellow), and K (black). Each of the data C1, M1, Y1, and K1 has a gradation number of 256 (0 to 255) and a resolution of 300 dpi. Specifically, in the color processing B, a three-dimensional lookup table (not shown) that associates R, G, and B input values with C, M, and Y output values is used. For input values that deviate from the values of the grid points in the table, the output values are obtained by interpolating the output values of the grid points in the surrounding table. Hereinafter, the data C1 among the data C1, M1, Y1, and K1 will be described as a representative.

  The data C1 is subjected to gradation correction using the gradation correction table (step S4). Data C1 after gradation correction is referred to as data C2. By performing quantization processing on the data C2 by the error diffusion method, data C3 (also referred to as “gradation data”) having two gradations (gradation levels 0 and 1) and a resolution of 300 dpi × 300 dpi is obtained. Obtain (step S5). In addition to the error diffusion method, a dither method may be used for the quantization process. The gradation data C3 is subjected to resolution conversion using the resolution conversion processing table (step S6). The data after resolution conversion is assumed to be image data C4. The image data C4 is developed in two gradations “0” and “1” based on a dot arrangement pattern that defines the number of dots arranged and the arrangement position. Specifically, the image data C4 is composed of 1-bit information of “0” and “1” at a resolution of 600 dpi × 600 dpi. The resolution (600 dpi × 600 dpi) of the image data C4 is higher than the resolution (300 dpi × 300 dpi) of the data C3.

  The recording data C5, M5, Y5, and K5 are transmitted to the recording head 102 (step S7), and cyan, magenta, yellow, and black ink are ejected from the recording head 102 in accordance with the recording data. (Step S9).

  FIG. 5 is an explanatory diagram of the image data converted by the resolution conversion process (step S6) in the present embodiment. The gradation data (300 dpi) having the gradation value “0” on the left side in FIG. 5A is converted into the image data (600 dpi) on the right side in FIG. 5, and “0” is entered in each pixel area in the image data. . The gradation data (300 dpi) having the gradation value “1” on the left side in FIG. 5B is converted into the image data (600 dpi) on the right side in FIG. 5 and “1” is entered in each pixel area in the image data. Dots are formed.

  FIG. 6 is an explanatory diagram of the relationship between the recording medium and the used nozzles during the recording operation. In FIG. 6, the discharge port array Lk for black ink will be representatively described. The same applies to the other ejection port arrays Lc, Lm, and Ly. First, in the first scan, an image is recorded in the area A1 using all the nozzles having nozzle numbers 1 to 256 while moving the recording head 102 together with the carriage 106 in the + X direction (outward direction) (outward recording). . After this first scan, the recording medium P is conveyed in the + Y direction for all nozzles (256 nozzles). In FIG. 5, for convenience of explanation, the recording head 102 is shown to move in the −Y direction. After the recording head 102 is returned to the −X direction together with the carriage 106, the second scan is performed. In the second scan, the image is recorded in the area A2 using all the nozzles having nozzle numbers 1 to 256 while moving the recording head 102 in the + X direction together with the carriage 106 again. After the second scan, the recording medium P is conveyed in the + Y direction for all nozzles (256 nozzles). Thereafter, the recording medium P is discharged in the + Y direction, and the recording operation is finished.

  As described above, the recording method in this example is a one-pass one-way recording method in which an image of a predetermined area (A1, A2) on the recording medium is completed by one-time scanning of the recording head 102 in one direction.

  FIG. 7A is an explanatory diagram of the drive order of the drive blocks (block B1 to block B16) in one nozzle row (for example, a nozzle row for black ink). FIG. 7B is an explanatory diagram of driving timing of the driving block for each column (column region) extending in the arrow Y direction, FIG. 7C is an explanatory diagram of ink dot formation positions, and FIG. FIG. 8 is an enlarged view of a part of FIG. The first column, the second column, the third column, and so on are located along the + X direction. In FIG. 8, for the convenience of explanation, the dot D1 formed during forward scanning will be described as a column reference.

  In even columns (first column, third column,...), Odd dots D1, D3, D5,... D15 are formed by nozzles in odd blocks (B1, B3, B5,..., B15). Is done. As shown in FIG. 8, these odd dots are shifted in the + X direction as the driving timing of the nozzles corresponding to them is later. The odd-numbered dots D1, D3, D5, and D7 have a driving order of the corresponding driving blocks B1, B3, B5, and B7 in the first half of No. 1 to No. 8, so ). The other odd-numbered dots D9, D11, D13, and D15 are driven toward the right side in FIG. 8 (the + X direction side) because the drive order of the corresponding drive blocks B9, B11, B13, and B15 is the latter half of the 9th to 16th. It is located near.

  As described above, the odd column is recorded by a combination of four odd dots positioned on the left side in FIG. 8 and four odd dots positioned on the right side in FIG.

  In even columns (second column, fourth column,...), Even dots D2, D4, D6,... D16 are formed by nozzles in even blocks (B2, B4, B6,..., B16). Is done. Similar to the odd dots, these even dots are shifted in the + X direction as the drive timing of the nozzles corresponding thereto is later. Even-numbered dots D2, D4, D6, and D8 are driven closer to the left side in FIG. 8 (toward the −X direction side) because the driving order of the corresponding driving blocks B2, B4, B6, and B8 is the first half of Nos. 1 to 8. ). The other even dots D10, D12, D14, and D16 are driven to the right side in FIG. 8 (the + X direction side) because the drive order of the corresponding drive blocks B10, B12, B14, and B16 is the latter half of the 9th to 16th. It is located near.

  In this way, the even column is recorded by a combination of four even dots located on the left side in FIG. 8 and four even dots located on the right side in FIG. Therefore, both the odd-numbered column and the even-numbered column are recorded by a combination of dots located on the right side and the left side in FIG. 9, and these dots are dispersedly arranged.

  The numbers in the squares in FIG. 7B represent the shift amount in the + X direction of the formation positions of the dots D1 to D16. The shift amount of dots formed during forward scanning (first scanning) corresponds to the drive order (first order) of blocks B1 to B16 corresponding to those dots as follows.

  That is, when the driving order of the block B1 is No. 1 and the deviation amount of the corresponding dot D1 in the + X direction is “1”, a dot whose driving timing is later by one than the dot D1 is + X The direction shift amount increases by “1”. Thus, the drive order number “1” of the block B1 corresponding to the dot D1 corresponds to the shift amount “1”. The same applies to other dots. For example, the first column dot D13 corresponding to the thirteenth driven block 13 has a shift amount of “13” and corresponds to the sixteenth driven block 15. The shift amount of the dot D16 in the second column is “16”.

  In the odd column, the odd block is not driven and the corresponding odd dot is not formed. In the even column, the even block is not driven, and the corresponding even dot is not formed. The recording data for recording the image at the time of forward scanning (at the time of the first scanning) is generated in such a manner that dots are not partially formed.

  As the numerical value in the square in FIG. 7B increases, the amount of dot shift in the + X direction increases. The average (average value C) of the deviation amounts in the + X direction of all dots in the first column is 8.5. The average value of dot shift in other columns is also 8.5. Thus, the average value of the amount of dot shift in each column means that the dots are arranged at substantially equal intervals in the X direction in each column. The average value of such shift amounts can be obtained by dividing the total shift amount in the + X direction of each dot by a multiple of the number of divisions of time-division driving. In the case of this example, an average value of the deviation amounts was obtained by dividing the total deviation amount by the number of divisions 16.

  Thus, in this embodiment, since the dots of each column are arranged at substantially equal intervals in the X direction, even when a solid image as shown in FIG. The occurrence of density unevenness can be suppressed. Further, by making a portion where dots are not formed (non-formed portion) differ between a plurality of columns, a deviation in the X direction suddenly occurs at the dot formation position between the previous print scan and the next print scan. Even when it occurs, it is possible to suppress the occurrence of density unevenness in the recorded image. Such a shift in the X direction at the dot formation position may occur depending on, for example, the scanning accuracy of the carriage 106 and the conveyance accuracy of the conveyance roller 103 and the auxiliary roller 104.

  The recording method is not limited to the one-pass unidirectional recording method, and the same effect can be obtained by, for example, a multi-pass unidirectional recording method.

(Comparative example)
14 and 15 are diagrams for explaining a comparative example, and the drive order of the drive blocks is set as shown in FIG. That is, after the odd blocks (blocks B1, B3, B5,..., B15) are driven, the even blocks (blocks B2, B4, B6,..., B16) are driven.

  The odd dots D1, D3, D5,... D15 formed in the odd columns (first column, third column,...) Have the driving blocks corresponding to them in the first half of the first to eighth driving order. Therefore, it is located on the left side (-X direction side) in FIG. On the other hand, in the odd dots D2, D4, D6,... D16 formed in the even columns (second column, fourth column,...), The driving order of the driving blocks corresponding to them is from No. 9 to No. 16. Since it is the latter half of FIG. 15, it is located on the right side in FIG.

  The interval in the + X direction of the dots forming each column changes due to such a deviation in the positions of the dots and variations in the amount of deviation of the dots. For example, the interval between the dots forming the first column and the dots forming the second column is increased, and the interval between the dots forming the second column and the dots forming the third column is decreased. As a result, density unevenness tends to occur in the recorded image.

(Second Embodiment)
The recording method employed in this embodiment is a two-pass bidirectional recording method in which an image in a predetermined area on a recording medium is completed by a total of two scans, forward scan and backward scan of the recording head 102.

  FIG. 4 is a flowchart for explaining the process of processing image data, and the distribution process of step S20 is added to the flowchart of FIG. 4 in the above-described embodiment. In step S20, the image data C4 whose resolution has been converted in step S6 is distributed to generate print data C5 corresponding to the discharge or non-discharge of cyan ink for each pixel area in each print scan. Similarly, the recording data M5 for magenta ink, the recording data Y5 for yellow ink, and the recording data K5 for black ink are also generated.

  FIG. 10 is an explanatory diagram of the relationship between the recording medium and the used nozzles during the recording operation. In FIG. 5, the discharge port array Lk for black ink will be representatively described. The same applies to the other ejection port arrays Lc, Lm, and Ly. The multi-pass printing method employed in this example is a two-pass printing method in which an image of a predetermined area (A1, A2, A3) on a printing medium is completed by scanning the printing head 102 twice. The recording head 102 moves in a first direction (+ X direction) that intersects (orthogonally in this example) the nozzle arrangement direction, and in a second direction (−X direction) opposite to the first direction.

  First, in the first scan, the recording head 102 is moved in the + X direction (outward direction) together with the carriage 106, and nozzles 1 to 128 are used to record an image in the area A1 (outward recording). After the first scan, the recording medium P is conveyed by 128 nozzles in the + Y direction. In FIG. 5, for convenience of explanation, the recording head 102 is shown to move in the −Y direction. In the second scan, the recording head 102 is moved in the −X direction (return direction) together with the carriage 106, and the nozzle numbers 1 to 256 are used to record images in the areas A1 and A2 (return path recording). . After the second scan, the recording medium P is conveyed by 128 nozzles in the + Y direction. In the third scan, the recording head 102 is moved in the + X direction (forward direction) together with the carriage 106, and nozzles with nozzle numbers 1 to 256 are used to record images in the areas A2 and A3 (outward recording). After the third scan, the recording medium P is conveyed by 128 nozzles in the + Y direction. In the fourth scan, while moving the recording head 102 together with the carriage 106 in the −X direction (return direction), the nozzle numbers 129 to 256 are used to record an image in the area A3 (return path recording). Thereafter, the recording medium P is discharged in the + Y direction, and the recording operation is finished.

  FIG. 11 is an explanatory diagram of a process of generating print data using image data and a mask pattern. FIG. 11A is a diagram schematically illustrating 16 pixels 600 to 615 in a certain unit region. In this example, for convenience of explanation, a description will be given using a unit region composed of 16 pixels. FIG. 11B shows image data corresponding to the unit area. In the image data of FIG. 11B, for example, the pixel value of the pixel 700 is “1”, so that ink is ejected to the pixel 700. According to the image data in FIG. 11B, ink is ejected to all the pixels in the unit area. FIGS. 11C-1 and 11C-2 are explanatory diagrams of first and second mask patterns corresponding to the first scan and the second scan in the 2-pass printing method. By applying the first mask pattern shown in FIG. 11C-1 to the image data shown in FIG. 11B, print data used in the first scan is generated. Similarly, print data used in the second scan is generated by applying the second mask pattern shown in FIG. 11C-2 to the image data shown in FIG. One-bit information of “0” or “1” is set for each pixel in the first and second mask patterns.

  FIG. 11D-1 is an explanatory diagram of the first print data generated by applying the first mask pattern of FIG. 11C-1 to the image data of FIG. 11B. is there. FIG. 11D-2 is an explanatory diagram of second print data generated by applying the first mask pattern of FIG. 11C-2 to the image data of FIG. 11B. is there. For example, in the pixel 600 of the first print data (FIG. 11 (d-1)) corresponding to the first scan, the pixel value of the image data is “1”, and the code value of the first mask pattern is “1”. ”, Ink ejection (“ 1 ”) is determined. Ink is ejected in the first and second scans based on the first and second print data generated in this way. For example, in the first scan, the pixel area on the recording medium for the pixels 700, 702, 705, 707, 708, 710, 713, and 715 is based on the first recording data in FIG. Ink is ejected.

  FIG. 11E shows recording data corresponding to the logical sum of the first and second recording data, and ink is ejected to a portion corresponding to the pixel value “1” of the image data in FIG. It will be. Thus, 1-bit print data used in each of a plurality of scans can be generated based on the image data and the mask pattern.

  FIG. 12A is an explanatory diagram of the drive order of the drive blocks (block B1 to block B16) at the time of forward printing and backward printing at one nozzle row (for example, nozzle row for black ink). In the case of this example, the drive order of the drive blocks at the time of forward printing is the same as the drive order of FIG. 7A in the first embodiment described above, and the drive order of the drive blocks at the time of backward print is It is the reverse of the driving order of time. FIG. 12B is an explanatory diagram of drive timing of the drive block for each column, FIG. 12C is an explanatory diagram of ink dot formation positions, and FIG. 13 is a partial enlargement of FIG. 12C. FIG. The first column, the second column, the third column, and so on are located along the + X direction.

  The odd-numbered columns (first column, third column,...) Include nozzles of odd-numbered blocks (B1, B5, B9, B13) driven during forward scanning and odd-numbered blocks (B3, B7) driven during backward scanning. , B11, B15). The even-numbered columns (second column, fourth column,...) Include nozzles of even-numbered blocks (B2, B6, B10, B14) driven during forward scanning and even-numbered blocks (B4, B8) driven during backward scanning. , B12, B16).

  In the odd columns, odd dots D1, D5, D9, and D13 are formed by the nozzles in the odd blocks (B1, B5, B9, and B13) during the forward scan in which the recording head moves in the + X direction. As shown in FIG. 13, these odd dots are shifted in the + X direction as the drive timing of the corresponding nozzles is delayed. The odd-numbered dots D1 and D5 are located on the left side in FIG. 13 (side on the −X direction side) because the driving order of the corresponding driving blocks B1 and B5 is the first half of Nos. 1 to 8. The odd-numbered dots D9 and D13 are located on the right side (near the + X direction) in FIG. 13 because the driving order of the corresponding driving blocks B9 and B13 is the second half of the ninth to the sixteenth.

  For odd columns, odd dots D3, D7, D11, and D15 are formed by the nozzles of the odd blocks (B3, B7, B11, and B15) during the backward scan in which the recording head moves in the -X direction. As shown in FIG. 13, these odd dots are shifted in the −X direction as the drive timing of the corresponding nozzles is delayed. The odd-numbered dots D3 and D7 are located on the right side in FIG. 13 (on the + X direction side) because the driving order of the driving blocks B3 and B7 corresponding to them is the first half from the first to the eighth. The odd-numbered dots D11 and D15 are located on the left side (near the −X direction side) in FIG. 13 because the driving order of the corresponding driving blocks B11 and B15 is the second half of the ninth to the sixteenth.

  Thus, the odd columns are recorded by a combination of the odd dots located on the left side in FIG. 13 and the odd dots located on the right side in FIG.

  On the other hand, in the even column, even dots D2, D6, D10, and D14 are formed by the nozzles of the even blocks (B2, B6, B10, and B14) during the forward scanning in which the recording head moves in the + X direction. As shown in FIG. 13, these even dots are shifted in the + X direction as the driving timing of the corresponding nozzles is delayed. Even-numbered dots D2 and D6 are positioned on the left side in FIG. 13 (on the −X direction side) because the driving order of the corresponding driving blocks B2 and B6 is the first half of Nos. 1 to 8. Even-numbered dots D10 and D14 are located on the right side (+ X direction side) in FIG. 13 because the driving order of the corresponding driving blocks B10 and B14 is the second half of the ninth to sixteenth.

  For odd columns, even dots D4, D8, D12, and D16 are formed by the nozzles of the even blocks (B4, B8, B12, and B16) during backward scanning in which the recording head moves in the -X direction. As shown in FIG. 13, these even dots are shifted in the -X direction as the driving timing of the corresponding nozzles is delayed. Even-numbered dots D4 and D8 are positioned closer to the right side in FIG. 13 (toward the + X direction) because the driving order of the corresponding driving blocks B4 and B8 is the first half of Nos. 1 to 8. Even-numbered dots D12 and D16 are located on the left side (near the −X direction) in FIG. 13 because the driving order of the corresponding driving blocks B12 and B16 is the second half of Nos. 9 to 16.

  In this way, the even column is recorded by a combination of the even dots located on the left side in FIG. 13 and the even dots located on the right side in FIG.

  The numbers in the squares in FIG. 12B represent the shift amounts in the + X direction of the formation positions of the dots D1 to D16 in the first, second column, and the third and fourth columns. The shift amount of dots formed during forward scanning (first scanning) corresponds to the drive order (first order) of blocks B1 to B16 corresponding to those dots as follows. At the time of forward scanning, since the driving order of the block B1 is No. 1, the formation position of the dot D1 corresponding to the block B1 is the leftmost, that is, the dot shift amount is “1”. A dot whose drive timing is later than that of the dot D1 by one increases in the amount of deviation in the + X direction by “1”. That is, in the forward scanning, the driving order of the recording elements corresponds to the amount of deviation of the dot formation position.

  Specifically, as shown in FIG. 12A, during forward scanning, blocks B1, B2, B4, B3, B5, B6, B8, B7, B9, B10, B12, B11, B13, B14, B16, B15 Driven in the order. Since forward scanning is scanning from the left to the right (+ X direction), even if the dots are recorded in the same column, the dot corresponding to the recording element driven at the previous timing is located on the left side. The dot corresponding to the printing element driven at a later timing is positioned on the right side. Here, it is assumed that in such forward scanning, ink is ejected from all of the printing elements corresponding to the blocks B1 to B16 to the same column. In this case, according to the driving order of the blocks B1, B2, B4, B3, B5, B6, B8, B7, B9, B10, B12, B11, B13, B14, B16, B15 from left to right , Dots corresponding to them are formed.

  Accordingly, the amount of dot shift during forward scanning is “1” in block B1, “2” in block B2, “4” in block B3, “3” in block B4, “5” in block B5, and in block B6. “6”, “8” in block B7, and “7” in block B8. Similarly, “9” in block B9, “10” in block B10, “12” in block B11, “11” in block B12, “13” in block B13, “14” in block B14, “16” in block B15 ”,“ 15 ”in block B16.

  On the other hand, the shift amount of dots formed at the time of backward scanning (second scanning) and the driving order (second order) of blocks B1 to B16 corresponding to these dots correspond as follows. At the time of backward scanning, since the driving order of the block B15 is No. 1, the formation position of the dot D15 corresponding to the block B15 is the rightmost side, that is, the dot shift amount is “16”. A dot whose driving timing is later by one than that of the dot D15 is shifted to the left, so that the dot shift amount is decreased by “1”. That is, at the time of backward scanning, a value related to the difference between the maximum value of the driving order (16 in this case) and the driving order of each printing element, more specifically, the number obtained by adding 1 to the difference is the amount of dot formation position deviation. Correspond.

  Specifically, during backward scanning, the blocks B15, B16, B14, B13, B11, B12, B10, B9, B7, B8, B6, B5, B3, B4, B2, B1 are driven in this order. Since the backward scan is a scan from right to left (−X direction), even if the dots are recorded in the same column, the dot corresponding to the printing element driven at the previous timing is positioned on the right side. However, the dot corresponding to the printing element driven at a later timing is positioned on the left side. Here, it is assumed that in such backward scanning, ink is ejected from all of the recording elements corresponding to the blocks B1 to B16 to the same column. In this case, according to the driving order of the blocks B1, B2, B4, B3, B5, B6, B8, B7, B9, B10, B12, B11, B13, B14, B16, B15 from left to right , Dots corresponding to them are formed.

  For example, since the block B1 is driven 16th, the dot formation position is “1”, which is the difference between 16 which is the maximum value in the driving order and 16 which is the driving order, plus 1. It becomes. In addition, since the block B16 is driven second, the dot formation position is “15”, which is the difference between 16 which is the maximum value in the driving order and 2 which is the driving order, plus 1. It becomes. The same applies to the other blocks: “2” in block B2, “4” in block B3, “3” in block B4, “5” in block B5, “6” in block B6, “8” in block B7, It becomes "7" in block B8. Similarly, “9” in block B9, “10” in block B10, “12” in block B11, “11” in block B12, “13” in block B13, “14” in block B14, “16” in block B15 "

  As the numerical value in the square in FIG. 12B increases, the amount of dot shift in the + X direction increases. The average (average value C) of the deviation amounts in the + X direction of all dots in the first column is 8.5. The average value of dot shift in other columns is also 8.5. Thus, the average value of the amount of dot shift in each column means that the degree of variation in the X direction of the dot formation position in each column is substantially equal. The average value of such shift amounts can be obtained by dividing the total shift amount in the + X direction of each dot by a multiple of the number of divisions of time-division driving. In the case of this example, an average value of the deviation amounts was obtained by dividing the total deviation amount by the number of divisions 16.

  As described above, in this embodiment, the average of the shift amounts of the dot formation positions in each column is made equal. For such a setting, the driving order is directly set to the value A for the printing element driven during the forward scanning, and 1 is added to the difference between the maximum value of the driving order and the driving order for the printing element driven during the backward scanning. When the number is a value A, the average of the values A is made almost equal in each column. As a result, the degree of variation of the dot formation position in the column in the X direction is made substantially equal, and the gradation shown in FIG. 12 (FIG. 12B) is such that ink is ejected to about half of all the pixels. As in c), an image with little density unevenness can be recorded.

  Further, as described in Patent Document 1, the driving order of the time division driving in the backward scanning may be set to an order different from the reverse order of the driving order of the time division driving in the forward scanning. As a result, even when there is a shift in the dot formation position in the scanning direction between the forward scan and the backward scan, compared to the case where such a shift has not occurred, the dot coverage area That is, the degree of change in density can be suppressed.

(Other embodiments)
In the above-described embodiment, the drive order of the drive blocks is set so that the difference in the shift amount of the dots in the + X direction between the columns is “0”. However, the difference is not necessarily zero, and by making it at least less than 3, the occurrence of density unevenness can be suppressed. Further, the number of divisions in the time division driving method is not limited to 16 as in the above-described embodiment, and is arbitrary. The multi-pass printing method is not limited to the two-pass printing method as in the above-described embodiment. Dots formed during the first scan and dots formed during the second scan according to the total number of times of the first scan and the second scan (multipass number) for forming an image in a predetermined area of the recording medium And the combination can be made different.

  The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

Claims (16)

A recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction;
Scanning means for scanning a unit area on a recording medium in a first direction intersecting the predetermined direction of the recording head;
Generating means for generating first recording data corresponding to an image to be recorded when scanning in the first direction;
Driving means for time-sharing driving the plurality of recording elements according to a first order when scanning in the first direction in order to form dots in the unit region;
A recording device comprising:
The generation means includes a non-formation portion where the dots are not formed with respect to the first column region and the second column region on the recording medium that extend in the predetermined direction and are located at different positions in the first direction. Generating the first recording data so as to be formed at different positions in the predetermined direction;
The average deviation amount of the dot formation position in the first direction in the first column region and the average deviation amount of the dot formation position in the first direction in the second column region are approximately The recording apparatus, wherein the first order is set to be equal.   When the order in the first order is a value A in the printing element that is driven when scanning in the first direction, the average deviation amount of the dot formation position in each of the first and second column regions is: The recording apparatus according to claim 1, wherein the recording apparatus corresponds to an average of the values A of the recording elements corresponding to the dots in each of the first and second column regions.   The recording apparatus according to claim 2, wherein a difference between the average of the values A in the first column area and the average of the values A in the second column area is less than 3. The recording head has a second recording element array different from the recording element array,
4. The drive unit according to claim 1, wherein the driving unit drives the plurality of printing elements in the second printing element array in a time division manner according to a third order when scanning in the first direction. 5. The recording apparatus according to item 1. A recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction;
Scanning means for performing scanning of the recording head in a first direction intersecting the predetermined direction and scanning of the recording head in a second direction opposite to the first direction with respect to a unit area on the recording medium When,
Generating means for generating first recording data corresponding to an image recorded at the time of scanning in the first direction and second recording data corresponding to an image recorded at the time of scanning in the second direction;
In order to form dots in the unit area, the plurality of recording elements are driven in a time-sharing manner according to a first order when scanning in the first direction, and the plurality according to a second order when scanning in the second direction. Driving means for time-division driving the recording element;
A recording device comprising:
When the dots formed when scanning in the first direction are first dots and the dots formed when scanning in the second direction are second dots, the generating means extend in the predetermined direction, respectively. , Non-formed portions where the first and second dots are not formed are formed at different positions in the predetermined direction with respect to the first and second column areas on the recording medium located at different positions in the first direction. And generating the first and second recording data,
The average shift amount of the formation positions of the first and second dots in the first direction in the first column region and the formation of the first and second dots in the first direction in the second column region. The recording apparatus, wherein the first order and the second order are set so that an average of positional deviation amounts is substantially equal.   In the printing element driven when scanning in the first direction, the order in the first order is the value A, and in the printing element driven when scanning in the second direction, the maximum value in the second order. And the value regarding the difference between the orders in the second order as a value A, the average of the displacement amounts of the first and second dot formation positions in the first and second column regions is the first, The recording apparatus according to claim 5, wherein the recording apparatus corresponds to an average of the values A of the recording elements corresponding to the first and second dots in each of the second column regions.   In the printing element driven when scanning in the second direction, the value A is a number obtained by adding 1 to the difference between the maximum value in the second order and the order in the second order. The recording apparatus according to claim 6.   8. The recording apparatus according to claim 6, wherein a difference between the average of the values A in the first column area and the average of the values A in the second column area is less than 3. 9. The recording head has a second recording element array different from the recording element array,
The driving means drives the plurality of recording elements in the second recording element array in a time-sharing manner according to a third order when scanning in the first direction, and performs the third order when scanning in the second direction. 9. The recording apparatus according to claim 5, wherein the plurality of recording elements in the second recording element array are time-division driven in accordance with a fourth order different from the reverse order. A recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction;
Scanning means for scanning a unit area on a recording medium in a first direction intersecting the predetermined direction of the recording head;
Generating means for generating first recording data corresponding to an image to be recorded when scanning in the first direction;
Driving means for time-sharing driving the plurality of recording elements according to a first order when scanning in the first direction in order to form dots in the unit region;
A recording device comprising:
The generation means includes a non-formation portion where the dots are not formed with respect to the first column region and the second column region on the recording medium that extend in the predetermined direction and are located at different positions in the first direction. Generating the first recording data so as to be formed at different positions in the predetermined direction;
In a printing element driven during scanning in the first direction, when the order in the first order is a value A, the average of the values A in the first column area and the value A in the second column area The recording apparatus is characterized in that the first order is set such that the average of the first order is substantially equal. A recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction;
Scanning means for performing scanning of the recording head in a first direction intersecting the predetermined direction and scanning of the recording head in a second direction opposite to the first direction with respect to a unit area on the recording medium When,
Generating means for generating first recording data corresponding to an image recorded at the time of scanning in the first direction and second recording data corresponding to an image recorded at the time of scanning in the second direction;
In order to form dots in the unit area, the plurality of recording elements are driven in a time-sharing manner according to a first order when scanning in the first direction, and the plurality according to a second order when scanning in the second direction. Driving means for time-division driving the recording element;
A recording device comprising:
When the dots formed when scanning in the first direction are first dots and the dots formed when scanning in the second direction are second dots, the generating means extend in the predetermined direction, respectively. , Non-formed portions where the first and second dots are not formed are formed at different positions in the predetermined direction with respect to the first and second column areas on the recording medium located at different positions in the first direction. And generating the first and second recording data,
In the printing element driven when scanning in the first direction, the order in the first order is the value A, and in the printing element driven when scanning in the second direction, the maximum in the second order. When the value A is a value related to the difference between the value and the order in the second order, the average of the value A in the first column region and the average of the value A in the second column region are substantially equal. The recording apparatus is characterized in that the first order and the second order are set. A recording method for recording using a recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction,
A scanning step of scanning the unit area on the recording medium in a first direction intersecting the predetermined direction of the recording head;
Generating a first recording data corresponding to an image to be recorded at the time of scanning in the first direction;
A driving step of time-sharing driving the plurality of recording elements according to a first order when scanning in the first direction to form dots in the unit region;
With
In the generation step, a non-formation portion where the dots are not formed is formed in each of the first column region and the second column region on the recording medium that extend in the predetermined direction and are located at different positions in the first direction. Generating the first recording data so as to be formed at different positions in the predetermined direction;
The average deviation amount of the dot formation position in the first direction in the first column region and the average deviation amount of the dot formation position in the first direction in the second column region are approximately The recording method, wherein the first order is set to be equal. A recording method for recording using a recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction,
A scanning step in which scanning of the recording head in a first direction intersecting the predetermined direction and scanning of the recording head in a second direction opposite to the first direction are performed on a unit area on the recording medium. When,
A generating step of generating first recording data corresponding to an image to be recorded when scanning in the first direction and second recording data corresponding to an image to be recorded when scanning in the second direction;
In order to form dots in the unit area, the plurality of recording elements are driven in a time-sharing manner according to a first order when scanning in the first direction, and the plurality according to a second order when scanning in the second direction. A driving process for driving the recording elements in a time-sharing manner,
With
When the dots formed when scanning in the first direction are the first dots and the dots formed when scanning in the second direction are the second dots, in the generation step, each dot extends in the predetermined direction. , Non-formed portions where the first and second dots are not formed are formed at different positions in the predetermined direction with respect to the first and second column areas on the recording medium located at different positions in the first direction. And generating the first and second recording data,
The average shift amount of the formation positions of the first and second dots in the first direction in the first column region and the formation of the first and second dots in the first direction in the second column region. The recording method according to claim 1, wherein the first order and the second order are set so that an average of positional deviation amounts is substantially equal. A recording method for recording using a recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction,
A scanning step of scanning the unit area on the recording medium in a first direction intersecting the predetermined direction of the recording head;
Generating a first recording data corresponding to an image to be recorded at the time of scanning in the first direction;
A driving step of time-sharing driving the plurality of recording elements according to a first order when scanning in the first direction to form dots in the unit region;
With
In the generation step, a non-formation portion where the dots are not formed is formed in each of the first column region and the second column region on the recording medium that extend in the predetermined direction and are located at different positions in the first direction. Generating the first recording data so as to be formed at different positions in the predetermined direction;
In a printing element driven during scanning in the first direction, when the order in the first order is a value A, the average of the values A in the first column area and the value A in the second column area The recording method is characterized in that the first order is set so that the average of the first and second averages is substantially equal. A recording method for recording using a recording head having a recording element array in which a plurality of recording elements are arranged in a predetermined direction,
A scanning step in which scanning of the recording head in a first direction intersecting the predetermined direction and scanning of the recording head in a second direction opposite to the first direction are performed on a unit area on the recording medium. When,
A generating step of generating first recording data corresponding to an image to be recorded when scanning in the first direction and second recording data corresponding to an image to be recorded when scanning in the second direction;
In order to form dots in the unit area, the plurality of recording elements are driven in a time-sharing manner according to a first order when scanning in the first direction, and the plurality according to a second order when scanning in the second direction. A driving process for driving the recording elements in a time-sharing manner,
With
When the dots formed when scanning in the first direction are the first dots and the dots formed when scanning in the second direction are the second dots, in the generation step, each dot extends in the predetermined direction. , Non-formed portions where the first and second dots are not formed are formed at different positions in the predetermined direction with respect to the first and second column areas on the recording medium located at different positions in the first direction. And generating the first and second recording data,
In the printing element driven when scanning in the first direction, the order in the first order is the value A, and in the printing element driven when scanning in the second direction, the maximum in the second order. When the value A is a value related to the difference between the value and the order in the second order, the average of the value A in the first column region and the average of the value A in the second column region are substantially equal. The recording method is characterized in that the first order and the second order are set.   A program for causing a computer to execute the recording method according to any one of claims 12 to 15.