JP2013154589A - Recording device and method of driving recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a difference of drive misalignment patterns with respect to each band when a recording device performs recording in which the number of recording elements of a group related to time-division driving and a band width related to recording medium carrying do not have a divisibility relation.SOLUTION: In two recordings relative to the first band, a set of driving orders "2", "8", "4", "6" and a set of driving orders "1", "7", "3", "5" are repeatedly used. Dot patterns of each set of driving orders "2", "8", "4", "6" and each set of driving orders "1", "7", "3", "5" are similar to each other within a pixel. By setting the two sets of driving orders, approximately the same driving misalignment pattern can be set among bands. As a result, dot arrangements among the bands also become approximately the same as each other, so as to suppress uneven density.

Description

  The present invention relates to a recording apparatus and a recording head driving method, and more particularly, to time-division driving of dots when driving a plurality of recording elements for forming dots such as nozzles for ejecting ink in the recording head in a time-sharing manner. The present invention relates to a technique for reducing density unevenness caused by deviation.

  In the time division drive of a plurality of recording elements in the recording head, a group is formed for each of a plurality of recording elements that are fewer than the plurality of recording elements, and a plurality of recording elements of the group are arranged at different timings for each of the recording element groups. It is driven sequentially to form dots. According to such time-division driving, the number of printing elements driven simultaneously can be reduced, and as a result, for example, the capacity of the power source used in the printing apparatus can be reduced.

  In this time-division driving, basically, the dot formation positions are shifted due to different driving timings within one pixel column corresponding to the recording element group. Then, this dot formation position shift forms a pattern of position shift for each band which is a unit area for completing recording (hereinafter, a pattern in one pixel row is referred to as a “drive shift pattern”). Also called).

  Here, when the number of recording elements in the recording element group related to time-division driving (× recording element arrangement pitch) and the width of the band determined by the conveyance of the recording medium are in a divisor relationship, there are a plurality of bands. The drive order of the recording elements is the same between the bands. In other words, the dilation relationship is a relationship in which one of the number of recording elements and the bandwidth is divisible, and in this case, the driving order is the same between the bands. As a result, the drive deviation pattern between the bands is the same.

JP 2011-37016 A JP 2009-39944 A

  However, when the number of recording elements in one group related to time-division driving and the width of the band determined by the conveyance of the recording medium are not in a divisor relationship, the driving order of the plurality of recording elements with respect to the band is between the bands. Different. As a result, the drive deviation pattern becomes different between bands, and density unevenness and color unevenness may occur between bands.

  For example, in the case of multi-pass printing in which printing of each band is completed by a plurality of scans, the drive order differs depending on the scan for printing a pixel when forming a dot of a certain pixel. As a result, the dot formation position in one pixel differs depending on the scan for forming the dot, resulting in the above-described difference in the drive deviation pattern. Such a difference in driving deviation pattern between bands appears as a slight difference in density between bands in a recorded image, for example, and may be recognized as density unevenness in the entire image.

  In addition, when the relationship described above is not a divisor relationship, by offsetting the recording element driving order in the recording element group for each band recording, the driving order of a plurality of recording elements with respect to the band is the same between the bands. can do. This offset method itself is described in Patent Document 1, for example. According to this offset driving order, the driving order for the bands is the same for all bands, and in the case of multi-pass printing, the driving order for each of a plurality of scans for completing band printing is the same. Can do. As a result, the dot formation position within one pixel is constant. However, even when time-division driving by offset is performed, a difference in driving deviation pattern occurs between bands, which may be recognized as density unevenness in the entire image. That is, even if the offset is performed, it is not solved that the driving order of the plurality of recording elements for recording the band differs for each band. As a result, the difference in the drive shift pattern for each band due to the difference in the drive order is reflected in the recorded image based on the recorded data, and may be recognized as density unevenness.

  The present invention can reduce the difference in driving deviation pattern for each band when performing recording in which the number of recording elements in a group related to time-division driving and the band width related to recording medium conveyance are not in a divisible relationship. An object of the present invention is to provide a recording apparatus and a recording head driving method.

  Therefore, in the present invention, a recording head having a recording element array in which a plurality of recording elements are arranged is scanned with respect to the recording medium in a direction intersecting with the arrangement direction of the recording elements. A recording apparatus that performs recording by transporting a recording medium in a direction along the arrangement direction of the recording elements during the scanning of the plurality of recording elements, and driving the plurality of recording elements in a time division manner in the scanning. A means for recording a pixel row along the array direction of the recording elements, the amount of the recording medium transported between the scanning and the next scanning and the number of recording elements having different driving orders in the time-division driving When one is indivisible with respect to the other, the common divisor of the number of recording elements having a different conveyance amount and the driving order of the recording medium, and between the recording element units constituted by consecutive recording elements in the recording element array As the difference between the number indicating each of the driving order recording elements successive said divisor is the same, is characterized in that comprises means, for performing time division driving of the plurality of recording elements.

  According to the above configuration, the drive order of each of the continuous recording elements is shown between the recording element units composed of the continuous divisors of the common divisors of the number of recording elements having different conveyance amounts and driving orders of the recording medium. A plurality of printing elements are time-division driven so that the number difference is the same. As a result, the drive deviation pattern due to time-division driving of the continuous recording elements becomes similar between the recording element units. As a result, when performing recording in which the number of recording elements in a group related to time-division driving and the bandwidth related to recording medium conveyance are not in a relation of reduction, it is possible to reduce the difference in driving deviation pattern for each band.

1 is a plan view showing an ink jet recording apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a schematic configuration of a control system of the recording apparatus illustrated in FIG. 1. It is a figure explaining the time division drive of the recording head performed in the said inkjet recording device. (A) And (b) is a figure explaining the process which produces | generates the binary recording data based on this embodiment. It is a figure explaining the period of the recording medium conveyance direction of the produced | generated binary recording data. It is a figure explaining the recording mode which can be performed in the recording device of embodiment of this invention. FIG. 6 is a diagram illustrating time-division driving in one recording mode of the present embodiment in which the paper feed amount is divisible by the number of nozzles in one group related to time-division driving. It is a figure explaining the time division drive which concerns on the comparative example of embodiment of this invention, when a paper feed amount is not divisible by the number of nozzles of one group concerning time division drive. It is a figure explaining the time division drive which concerns on the other comparative example of embodiment of this invention, when a paper feed amount is not divisible by the number of nozzles of one group concerning time division drive. It is a figure explaining the time division drive which concerns on one Embodiment of this invention. It is a figure which shows the drive shift pattern by the time division drive which concerns on the said embodiment. (A) And (b) is a figure which shows the table of the time division drive used in the said embodiment. It is a flowchart which shows the setting process of the drive sequence of the time division drive according to the recording mode in the said embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a plan view showing an ink jet recording apparatus (hereinafter also simply referred to as a recording apparatus) according to an embodiment of the present invention. The ink jet recording apparatus shown here is capable of recording on a relatively large size recording medium, and includes a recording apparatus main body 2 including a transport unit (not shown) that transports the recording medium in the Y direction (transport direction). . The main body 2 is provided with a carriage 1 attached so as to be movable along the guide shaft 33 in the main scanning direction. The carriage 1 is configured to be capable of reciprocating along the main scanning direction (X direction) by a driving force transmitted from a carriage motor (not shown) via a belt 34. The carriage 1 includes a recording head 5 having a plurality of nozzles (recording elements) for ejecting ink droplets so as to correspond to yellow (Y), magenta (M), cyan (C), and black (K) inks. Are installed. As a result, the recording head 5 performs scanning in the main scanning direction, which is the direction intersecting the nozzle arrangement direction, by the movement of the carriage 1. The recording head 5 corresponding to each of Y, M, C, and K inks includes a nozzle array (recording element array) described later with reference to FIG. Each ink color nozzle row is composed of 1280 nozzles, and these nozzles are driven by time-division driving described later with reference to FIG. 9 to eject ink. The carriage 1 is provided with an optical sensor 32. The optical sensor 32 detects the presence or absence of a recording medium on the platen 4 while moving in the main scanning direction together with the carriage 1.

  In addition, the ink jet recording apparatus of the present embodiment includes a non-ejection nozzle detection unit 36 having a light projecting unit and a light receiving unit that can detect ink non-ejection of each nozzle of the recording head. Specifically, the non-ejection of each nozzle is detected by detecting the presence or absence of ink droplets that block the optical path from the light projecting unit to the light receiving unit.

  Further, this ink jet recording apparatus is provided with a recording head recovery means in order to keep the ejection performance of each nozzle of the recording head 5 in an appropriate state. This recovery means covers the discharge port formed at the nozzle tip of the recording head 5 with a cap connected to a pump, and sucks and discharges thickened ink in the nozzle by the negative pressure generated in the cap by the pump. So-called suction recovery mechanism 30. In order to enhance the ink ejection stability, the ink collection boxes 31A and 31B are configured to perform a preliminary ejection operation in the non-printing area immediately before the recording operation.

  FIG. 2 is a block diagram showing a schematic configuration of a control system of the recording apparatus shown in FIG. The main control unit 300 includes a CPU 301 that executes processing operations such as calculation, determination, and control, a ROM 302 that stores a control program to be executed by the CPU 301, a RAM 303 that is used as a buffer for recording data, and an input / output port 304. Etc. The CPU 301 executes processing or print head drive control, which will be described later with reference to FIG.

Connected to the input / output port 304 are respective drive circuits 305, 306, 307, and 308 such as a conveyance motor (LF motor) 312, a carriage motor (CR motor) 313, the recording head 5, and an actuator in the cutting unit. Further, various sensors are connected to the input / output port 304. For example, a head temperature sensor 314 that detects the temperature of the recording head, a home position sensor 314 that detects the position of the home position that performs the recovery operation of the recording head, and an undischarge nozzle detection unit that inspects the ejection state of the recording head 5 are connected. Has been. Further, the main control unit 300 is connected to the host computer 315 via the interface circuit 311.
FIG. 3 is a diagram for explaining basic time-division driving of the recording head according to the present embodiment. In the recording head of this embodiment, as described above with reference to FIG. 1, the nozzle row of each color ink is composed of 1280 nozzles. In the time-division driving configuration, each 1280 nozzle is basically divided into a plurality of nozzle groups (nozzle groups) of 40 nozzles that are continuous in the nozzle array. Then, 40 nozzles of each nozzle group are sequentially driven at different timings. With respect to these timings, the nozzles driven at the same timing between the groups constitute respective blocks related to time-division driving. In other words, the 40 nozzles of each nozzle group can be said to be the number of nozzles having a different driving order in the time-division driving.

  In FIG. 3, for the sake of simplicity of illustration and description, each nozzle group has eight nozzles (0-7), (8-15), (16- 23). Then, nozzle groups (0, 8, 16), (1, 9, 17), (2, 10, 18), (3) having the same driving order (simultaneous driving) in the driving orders 1 to 8 between these groups. , 11, 19), (4, 12, 20), (5, 13, 21), (6, 14, 22), and (7, 15, 23) constitute blocks of time-division driving. Specifically, in the recording head drive circuit, each block in the drive order 1 to 8 is sequentially selected based on the block enable signal, so that the nozzles are sequentially driven at the same timing for each block.

  By performing the time-division driving described above, a drive deviation pattern is generated for each nozzle group as shown in FIG. In other words, the landing position of the ejected ink is shifted due to the difference in driving timing, and the position of the dot formed in the 1200 dpi pixel row (column) is shifted. The shifted dots form a drive shift pattern corresponding to the drive timing. In the example shown in the figure, in all the pixels in the pixel row, the recording data is data indicating ink ejection (“1”), and there is a pixel where the recording data is non-ink ejection (“0”). Of course, the dot is not formed.

  FIGS. 4A and 4B are diagrams for explaining the processing for generating binary print data according to the present embodiment, which is recorded by time-division driving of the print head described above with reference to FIG. is there.

  As shown in FIG. 4A, RGB 256-gradation multi-valued image data (1) for each 600 dpi pixel is converted into CMYK 256-graded multi-valued image data (2) by color separation processing. Is done. Next, the CMYK multi-valued image data (2) is reduced in gradation by the quantization process to N-value, in this embodiment, 4-valued data (3). Then, the index pattern data (4) is referred to based on any one of levels 0 to 4 indicated by the quaternary data (3), and binary recording data of 1200 dpi 2 pixels × 2 pixels is generated. . FIG. 4B shows details of processing for generating binary data in accordance with the level indicated by the quaternary data (3). In the present embodiment, four types (I, II, III, IV) of 2 × 2 pixel index patterns are prepared for each level. These patterns are selected by referring to the pattern selection matrix table according to the level indicated by the quaternary data (3), and finally, binary data of 2 pixels × 2 pixels is generated.

  In the present embodiment, as shown in FIG. 4B, the size in the Y direction of the pattern selection matrix table, that is, the size in the conveyance direction of the recording medium (recording paper) is assumed to be the same as the above-described bandwidth (band period). Yes. Thereby, as shown in FIG. 5, the generated binary recording data has the same period as the bandwidth in the Y direction. As described above, this band is a unit area that completes recording by scanning the recording head. In the case of multi-pass recording, this band corresponds to the transport amount (predetermined amount) of the recording medium that is transported during multiple scans. It is a thing. The predetermined amount is smaller than the arrangement length of the nozzles, so that the recording of the band having the predetermined amount of width (band width) can be completed by scanning the recording head a plurality of times.

  In the present embodiment, as will be described later with reference to FIG. 6, when the recording medium transport amount (paper feed amount) changes in accordance with a plurality of recording modes according to the present embodiment, the above-described pattern selection matrix is correspondingly changed. The size of the table in the Y direction is made the same as the transport amount in the recording mode. This is described in, for example, Patent Document 2, and the size of the pattern selection matrix table in the Y direction is changed in accordance with the change in the carry amount, thereby matching the cycle of the mask pattern used for multi-pass printing. Is. This makes it possible to match the generation cycle of the binary recording data with the bandwidth, and to suppress image quality deterioration caused by the difference in the arrangement of dots to be formed and the order of printing.

  FIG. 6 is a diagram illustrating a recording mode that can be executed in the recording apparatus of the present embodiment. In FIG. 6, the recording mode “1” is 8-pass multi-pass recording that completes recording of each band in 8 scans. In this 8-pass printing mode, the total number of nozzles 1280 for each color ink is divisible by the number of scans 8, so all 1280 nozzles are used, and the quotient 160 (× nozzle arrangement pitch) obtained by dividing 1280 by 8 is used. Use paper feed amount. On the other hand, the recording head drive circuit of the present embodiment is configured so that 40 blocks are time-division driven, that is, 1280 nozzles can be time-division driven in the order of No. 1 to 40 for each group of 40 nozzles. An enable signal decoder and signal lines are configured. In such a recording mode 1, since the paper feed amount is divisible by 40 nozzles of each group related to time division, the time division drive described later in FIG. 7 is performed using the drive table “Type A” shown in FIG. .

  On the other hand, the recording modes “2” and “3” are 6-pass and 7-pass recording modes, respectively. In this case, since the total number of nozzles 1280 cannot be divided by 6 and 7, the recording operation is performed with the number of nozzles divisible by each. Specifically, considering the unit for performing efficient data processing, the number of used nozzles is the number of nozzles 1248 for 6 passes and the number of nozzles 1232 for 7 passes. The paper feed amounts are 208 and 176 (× nozzle arrangement pitch) which are quotients when the number of used nozzles is divisible. In the time-division driving in these recording modes, each paper feed amount is not divisible by the 40 nozzles of each group related to time-division, so the drive table “Type B” shown in FIG. Time-division driving described later is performed. That is, the driving order is such that the same driving deviation pattern is repeated in units of 8 nozzles, and in terms of the configuration of the driving circuit, 40 nozzles / group, but the number of time-division blocks remains 40, and apparently 8 nozzles / group. Perform group time-division drive.

  As described above, the drive control of the recording head according to the embodiment of the present invention includes the number of nozzles × nozzle arrangement pitch in one group related to time-division driving and the band width corresponding to the conveyance amount of the recording medium. It is applied when there is no relation of dilation. Here, as described above, the band is a unit area that completes recording by scanning the recording head. For example, the recording is completed by carrying a predetermined amount of recording medium between a plurality of scans and each scan. In this case, a region having the predetermined amount of width becomes a band. Further, the dilation relationship is a relationship in which the other is divisible by either one of the number of nozzles × nozzle arrangement pitch and the band width.

  Hereinafter, with reference to FIGS. 7 to 10, the time-division driving in the recording mode using Type B according to an embodiment of the present invention will be described.

  FIG. 7 is a diagram for explaining time-division driving using the Type A table in the recording mode “1” described above, in which the paper feed amount is divisible by the number of nozzles of one group related to time-division driving. In the figure, for simplification of explanation and illustration, the number of nozzles in one group related to time division is eight and the number of blocks in time division is eight. On the other hand, conveyance is performed by multi-pass printing of two passes. An example is shown in which the amount is 8 nozzles (× nozzle arrangement pitch). In addition, although driving of a nozzle row of one ink color is described, it goes without saying that driving of nozzle rows of other ink colors is the same.

  As shown in FIG. 7, in the first scan for the first band, printing is performed by the nozzles 8 to 15, and at that time, the nozzles 8 to 15 are “1”, “8”, “5”, “2”, “ Driven in the order of “6”, “4”, “3”, “7”. After this first scan, the paper feed for 8 nozzles (× nozzle arrangement pitch), which is the same as the number of nozzles 8 in one group, is performed. That is, the case where the paper feed amount is divisible by the number of nozzles of one group related to time-division driving is shown. After this paper feed, recording is performed by nozzles 0 to 7 in the second scan for the first band. At that time, nozzles 0 to 7 are “1”, “8”, “5”, “2”, “6”. ”,“ 4 ”,“ 3 ”,“ 7 ”. Thereafter, time-division driving for the second band is similarly performed in the second and third scans.

  In the above time-division driving, as shown in FIG. 7, the driving deviation pattern due to the difference in driving timing is the same between the first band and the second band. Then, when the time-division driving described above is performed according to the binary recording data based on the input image data, the dot arrangement recording result shown in FIG. 7 is obtained. For example, the dot arrangement of the pixel row (column) “1” in the paper feed direction is indicated by the numeral “1”, and as is clear from this, the dot arrangement between the bands is the same. As a result, density unevenness due to a difference in dot arrangement between bands does not occur.

  FIG. 8 is a diagram illustrating time-division driving according to a comparative example of the embodiment of the present invention when the paper feed amount is not divisible by the number of nozzles of one group related to time-division driving. For the sake of simplification of explanation and illustration, this figure shows an example in which the number of nozzles in one group related to time division is 8 and the number of blocks in time division is 8, as in FIG. An example in which the carry amount is 12 nozzles (× nozzle arrangement pitch) in pass printing is shown. That is, the transport amount (12) is not divisible by 8 nozzles in one group.

  As shown in FIG. 8, in the first scan with respect to the first band, recording is performed by the nozzles 12 to 23. At this time, the nozzles 12 to 23 are “6”, “4”, “3”, “7”, It is driven in the order of “1”, “8”, “5”, “2”, “6”, “4”, “3”, “7”, that is, a period of 8 time-division blocks. After this first scan, paper feed for 12 nozzles (× nozzle arrangement pitch) that cannot be divided by 8 nozzles in one group is performed. After this paper feed, recording is performed by nozzles 0 to 11 in the second scan for the first band. At this time, nozzles 0 to 11 are “1”, “8”, “5”, “2”, “6”. ”,“ 4 ”,“ 3 ”,“ 7 ”,“ 1 ”,“ 8 ”,“ 5 ”,“ 2 ”, that is, the drive is performed with a period of 8. The time-division driving for the second band is similarly performed in the second scan and the third scan.

  In the time-division drive described above, as shown in FIG. 8, in each band, the drive deviation (1st and 2nd) differs depending on whether the scanning time for recording the band is the first scan or the second scan. As a result, the dot formation position (dot arrangement of “1” in the first column) in the recording result is greatly different. As a result, the dot arrangement differs depending on the number of scans, which may cause uneven density for each band.

  FIG. 9 is a diagram illustrating time-division driving according to another comparative example of the embodiment of the present invention when the paper feed amount is not divisible by the number of nozzles of one group related to time-division driving. This figure shows an example in which the driving order is offset in order to eliminate the difference in driving deviation (1st and 2nd) depending on the scanning time for recording the band described above in FIG.

  As shown in FIG. 9, in the first scan with respect to the first band, recording is performed by the nozzles 12 to 23. At this time, the nozzles 12 to 23 are “6”, “4”, “3”, “7”, It is driven in the order of “1”, “8”, “5”, “2”, “6”, “4”, “3”, “7”. After this first scan, paper feed for 12 nozzles (× nozzle arrangement pitch) that cannot be divided by 8 nozzles in one group is performed. After this paper feed, recording is performed by nozzles 0 to 11 in the second scan for the first band, but the driving order is offset by four, unlike the comparative example shown in FIG. As a result, the nozzles 0 to 11 are “6”, “4”, “3”, “7”, “1”, “8”, “5”, “2”, “6”, “4”, “3”. ”And“ 7 ”in this order.

  Similarly, in the second scan (first scan) with respect to the second band, printing is performed by the nozzles 12 to 23. At this time, the nozzles 12 to 23 are “1”, “8”, “5”, “2”. , “6”, “4”, “3”, “7”, “1”, “8”, “5”, “2”. In addition, after this first scan, in the third scan (second scan) for the second band, printing is performed by nozzles 0 to 11, and nozzles 0 to 11 are “1”, “8”, and “5”. , “2”, “6”, “4”, “3”, “7”, “1”, “8”, “5”, “2”.

  According to the time-division driving to which the offset described above is applied, as shown in FIG. 9, the driving deviation does not differ depending on whether the scanning time is the first scanning or the second scanning, and the same driving deviation pattern is obtained. As a result, the dot arrangement does not differ depending on the scanning time. However, as a result of different driving deviation patterns between bands, the dot arrangement also differs between bands, and density unevenness due to this may occur.

  FIG. 10 is a diagram illustrating time-division driving according to an embodiment of the present invention, in which time-division using a Type B table when the paper feed amount cannot be divided by the number of nozzles of one group related to time-division driving. Indicates driving. The figure shows an example in which the offset described above in FIG. 9 is applied.

  As shown in FIG. 10, in the first scan with respect to the first band, recording is performed by the nozzles 12 to 23. At this time, the nozzles 12 to 23 are “2”, “8”, “4”, “6”, It is driven in the order of “1”, “7”, “3”, “5”, “2”, “8”, “4”, “6”. After this first scan, paper feed is performed for 12 nozzles (× nozzle arrangement pitch) that cannot be divided by the number of nozzles 8 in one group related to time-division driving. After this paper feed, in the second scan for the first band, printing is performed by nozzles 0 to 11, but the driving order is offset by four. As a result, the nozzles 0 to 11 are the same as in the first scan, “2”, “8”, “4”, “6”, “1”, “7”, “3”, “5”, “2”. , “8”, “4”, “6” in this order.

  Next, in the second scan (first scan) with respect to the second band, printing is performed by the nozzles 12 to 23. At this time, the nozzles 12 to 23 are “1”, “7”, “3”, “5”. , “2”, “8”, “4”, “6”, “1”, “7”, “3”, “5”. In addition, after this first scan, in the third scan (second scan) for the second band, printing is performed by nozzles 0 to 11, and nozzles 0 to 11 are “1”, “7”, “3”. , “5”, “2”, “8”, “4”, “6”, “1”, “7”, “3”, “5”.

  As shown in FIG. 10, the time-division drive according to the embodiment of the present invention described above includes a set of drive orders “1”, “7”, “3”, “5”, and a drive order “2”. A set of “8”, “4”, and “6” is repeatedly used. That is, as shown in FIG. 11, the set of drive orders “1”, “7”, “3”, “5” and the set of drive orders “2”, “8”, “4”, “6” In the pixel, dots are formed at the respective drive timings as the recording head scans in the right direction in FIG. As a result, the dot patterns of each set are similar to each other.

  Specifically, in the combination of the driving order “1”, “7”, “3”, “5”, the number difference pair indicating the driving order is (“1” → “7” = 6, “7” → “ 3 ”= 4,“ 3 ”→“ 5 ”= 2), and even in the drive order“ 2 ”,“ 8 ”,“ 4 ”,“ 6 ”pairs, the above difference group is (“ 2 ”→“ 8 ”= 6,“ 8 ”→“ 4 ”= 4,“ 4 ”→“ 6 ”= 2), and the combinations of the above differences are equal to each other. In addition to the combinations of the driving orders described above, for example, the driving orders “1”, “3”, “7”, “5” and the driving orders “2”, “4”, “8”, “6” Pairs can also be used. These sets are also equal to each other in the number difference set indicating the driving order (2, 4, 2). In this way, in each group that performs time-division driving, there are naturally a plurality of (two in the example shown in FIG. 10) pairs of difference in the number indicating the driving order, under the condition that the driving order does not overlap. Set the driving order set. Thereby, it can be set as the substantially same drive shift pattern between bands. In this case, the cycle of substantially the same drive deviation pattern is 4 nozzles. In the present specification, the substantially same drive deviation pattern or the cycle of the drive order is represented by N. In the example shown in FIG. 10, N = 4, and as described above with reference to FIG. 6, four nozzles that apparently constitute a recording element unit are repeatedly used, and the number of nozzles in each group related to time-division driving is 4 ( The number of nozzles / group in FIG. 6 corresponds to “8”). Here, N = 4 is the greatest common divisor of the number of nozzles 8 and the paper feed amount 12 in one nozzle group. In the present embodiment, the greatest common divisor is N, but is not limited thereto. For example, the driving order “1”, “2”, the driving order “3”, “4”, the driving order “5”, “6”, the driving order “7”, “8”, and N = 2 may be set. it can. That is, the common divisor of the number of nozzles 8 and the paper feed amount 12 in one nozzle group may be used.

  The drive order described above is set in the process shown in FIG. 13 by the CPU 301 described with reference to FIG. 2, and specifically, is performed by selecting a drive block based on the setting of the block enable signal.

  According to the embodiment of the present invention described above, the drive deviation patterns are almost the same between the bands. As a result, the dot arrangement between the bands is substantially the same, and density unevenness can be suppressed.

  FIGS. 12A and 12B are diagrams showing a time-division drive table used in accordance with the recording mode of the present embodiment described above. Specifically, FIG. 12A shows a drive table of “Type A” used in the recording mode “1” described above with reference to FIG. 6, and FIG. 12B shows that it is used in the recording modes “2” and “3”. The drive table of “Type B” is shown. The “Type B” drive table used in the recording mode in which the paper feed amount is not divisible by the number of nozzles 40 / group is a table when the number of nozzles in each group apparently becomes 8, as described with reference to FIG. That is, the apparent number of nozzles is divided into 8 / group, and in each group, the nozzle drive (discharge) order is set as described with reference to FIGS. For example, the group of nozzles 0 to 7 is the driving order “0”, “5”, “30”, “20”, “25”, “10”, “15”, and the group of nozzles 8 to 15 is The drive order is “1”, “6”, “31”, “21”, “26”, “11”, “16”, in which the difference in the number indicating the same drive order is the same.

  FIG. 13 is a flowchart showing the drive order setting process for time-division driving according to the recording mode in the present embodiment described above. First, in step S1201, information on the recording mode selected by the user is acquired. Next, in step S1202, it is determined whether or not the acquired paper feed amount in the recording mode is divisible by the number of nozzles / group related to time-division driving. When it is determined that it is divisible, that is, when the acquired mode is the recording mode “1”, the type A drive table is selected and set in step S1203.

  On the other hand, if it is determined that it is not divisible, it is determined in step S1204 whether or not the obtained paper feed amount in the recording mode is divisible by the apparent number of nozzles N = 8 in the time division drive. When it is determined that it is divisible, that is, when the acquired mode is the recording mode “2” or “3”, the type B drive table is selected and set. If it is determined in step S1204 that it is not divisible, the type A drive table is selected and set in step S1203.

(Other embodiments)
The embodiment described above relates to an example in which the drive order is offset, but the application of the present invention is not limited to this form, and the present invention can also be applied to time-division drive in which no offset is applied. That is, in FIG. 10, in the first scan for the first band, as described above, the nozzles 12 to 23 are used, and the driving order of the nozzles 0 to 11 is “2”, “8”, “4”, “6”. ”,“ 1 ”,“ 7 ”,“ 3 ”,“ 5 ”,“ 2 ”,“ 8 ”,“ 4 ”,“ 6 ”. When the driving order is not offset between the first scan and the second scan, the driving order of the nozzles 0 to 11 that record the first band in the second scan is “1”, “7”, “ 3 ”,“ 5 ”,“ 2 ”,“ 8 ”,“ 4 ”,“ 6 ”,“ 1 ”,“ 7 ”,“ 3 ”,“ 5 ”. That is, in the first scan, a set of drive orders “2”, “8”, “4”, “6”, a set of drive orders “1”, “7”, “3”, “5”, a drive order “ Driven in the order of “2”, “8”, “4”, “6”. On the other hand, in the second scan, the drive order “1”, “7”, “3”, “5” set, the drive order “2”, “8”, “4”, “6” set, and the drive order “ Driven in the order of 1 ”,“ 7 ”,“ 3 ”,“ 5 ”. Here, a set of drive orders “2”, “8”, “4”, “6” and drive orders “1”, “7”, “3”, which are pairs of corresponding drive orders for the same pixel. , “5” is not the same as in the embodiment shown in FIG. 10, but as described above, the drive deviation patterns are similar to each other. As a result, the drive deviation pattern between bands can be made substantially the same.

  Further, the above-described embodiment relates to an example in which the present invention is applied to the time division drive of the recording head in multi-pass printing, but the application of the present invention is not limited to this form. For example, the present invention can also be applied to a recording mode in which each band completes printing in one scan, and a part of the nozzles are not used and the nozzles used between the bands are different. For example, the present invention can also be applied to a recording mode in which the first band is used for the nozzles 12 to 23 and the second band is used for the nozzles 0 to 11 to perform recording in one scan.

  Furthermore, the present invention is not limited to an ink jet recording apparatus. For example, the present invention can be applied to a recording apparatus that performs recording by forming dots such as using a transfer ribbon.

1 Carriage 5 Recording Head 301 CPU
302 ROM
303 RAM

Claims (6)

A recording head having a recording element array in which a plurality of recording elements are arranged is scanned a plurality of times with respect to the recording medium in a direction intersecting with the arrangement direction of the recording elements, and during each of the plurality of scans of the recording head. Then, a recording apparatus that completes recording of the unit area of the predetermined amount by conveying the recording medium in a direction along the arrangement direction of the recording elements by a predetermined amount smaller than the arrangement length of the plurality of recording elements. Because
Means for driving the plurality of recording elements in a time-sharing manner in each of the plurality of scans to record a pixel row along the arrangement direction of the plurality of recording elements, When one of the number of recording elements having a different driving order in the fixed amount and the time-division driving is not divisible with respect to the other, the recording factor of the common divisor of the transport amount of the recording medium and the number of recording elements having the different driving order The time division of the plurality of recording elements is performed so that the difference in the number indicating the driving order of each of the continuous printing elements of the common divisor is the same between the printing element units constituted by the continuous printing elements in the element array. Means for driving,
A recording apparatus characterized by comprising:   The means offsets the drive order of the plurality of recording elements between a plurality of scans for completing the recording of the unit area, and can record the same pixel row in the scanning direction in the unit area. The recording apparatus according to claim 1, wherein the drive order of the elements is the same. The recording apparatus generates binary recording data using an index pattern that defines the arrangement of binary recording data, selects the index pattern to be used according to a pattern selection matrix,
The recording apparatus according to claim 1, wherein the predetermined amount of recording medium conveyance matches a size of the pattern selection matrix in a conveyance direction of the recording medium. A recording head including a recording element array in which a plurality of recording elements are arranged is scanned with respect to the recording medium in a direction intersecting the arrangement direction of the recording elements, and between the scanning of the recording head and the next scanning, A recording apparatus that performs recording by conveying a recording medium in a direction along the arrangement direction of the recording elements,
Means for driving the plurality of recording elements in a time division manner in the scanning to perform recording of a pixel row along an arrangement direction of the plurality of recording elements, and a recording medium between the scanning and the next scanning When one of the transport amount and the number of recording elements having a different driving order in the time-division driving is not divisible with respect to the other, the common divisor of the transport amount of the recording medium and the number of recording elements having the different driving order is The plurality of printing elements are arranged such that the number difference indicating the driving order of the printing elements having consecutive common divisors is the same between printing element units constituted by printing elements continuous in the printing element array. Means for time-division driving,
A recording apparatus characterized by comprising: A recording head including a recording element array in which a plurality of recording elements are arranged is scanned with respect to the recording medium in a direction intersecting the arrangement direction of the recording elements, and between the scanning of the recording head and the next scanning, A method for driving the recording head in a recording apparatus that performs recording by conveying a recording medium in a direction along the arrangement direction of the recording elements,
In the scanning, the plurality of recording elements are driven in a time division manner to record a pixel row along the arrangement direction of the plurality of recording elements, and a recording medium between the scanning and the next scanning When one of the transport amount and the number of recording elements having a different driving order in the time-division driving is not divisible with respect to the other, the common divisor of the transport amount of the recording medium and the number of recording elements having the different driving order is The plurality of printing elements are arranged such that the number difference indicating the driving order of the printing elements having consecutive common divisors is the same between printing element units constituted by printing elements continuous in the printing element array. A process of time-division driving,
A recording head driving method characterized by comprising: A recording head having a recording element array in which a plurality of recording elements are arranged is scanned a plurality of times with respect to the recording medium in a direction intersecting with the arrangement direction of the recording elements, and during each of the plurality of scans of the recording head. Then, a recording apparatus that completes recording of the unit area of the predetermined amount by conveying the recording medium in a direction along the arrangement direction of the recording elements by a predetermined amount smaller than the arrangement length of the plurality of recording elements. A method of driving the recording head,
A step of driving the plurality of recording elements in a time-sharing manner in each of the plurality of scans to record a pixel row along an arrangement direction of the plurality of recording elements. When one of the number of recording elements having a different driving order in the fixed amount and the time-division driving is not divisible with respect to the other, the recording factor of the common divisor of the transport amount of the recording medium and the number of recording elements having the different driving order The time division of the plurality of recording elements is performed so that the difference in the number indicating the driving order of each of the continuous printing elements of the common divisor is the same between the printing element units constituted by the continuous printing elements in the element array. A process of driving,
A recording head driving method characterized by comprising:

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