JP2014136336A - Recording device and method for generating recording data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce density unevenness by obtaining combination of recording elements whose dot sizes to be recorded are different for a recording element of an area (connecting area) in which two recording element chips overlap with simple processing in a recording device.SOLUTION: Distribution ratio of large and small dots is used to correspond to each of an overlapping area and a non-overlapping area between a recording element chip A71 and a recording element chip A72 when generating recording data. In the overlapping area, distribution of the large and small dots are performed based on the distribution ratio of large and small dots without distinguishing the recording element chips. Dot distribution processing (connecting mask processing) same as that in recording is performed, and it is determined which nozzle of the recording element chip is used for the overlapping area. Thus, even in the overlapping area of the recording element chips, the distribution ratio of large and small dots can be determined by the same processing as that of the non-overlapping area.

Description

  The present invention relates to a recording apparatus and a recording data generation method. Specifically, when performing recording using a recording head in which a plurality of recording elements such as nozzles with different recording dot sizes are arranged, the ratio of recording data distribution between the recording elements with different recording dot sizes is set. The present invention relates to a technique for reducing density unevenness by adjusting.

  2. Description of the Related Art There is known a recording apparatus that performs gradation recording using a recording head in which a plurality of nozzles serving as recording elements having different amounts of ink to be ejected and differently recorded dot sizes are arranged. In this type of recording apparatus, a desired recording density is reproduced by combining dots of different sizes recorded by the respective nozzles. In the generation of print data, print data is distributed among nozzles with different dot sizes to be printed in order to obtain this combination of dots.

  Patent Document 1 describes that the nozzles are selected and driven so that the average discharge amount of the nozzles for realizing the combination of dots is equal to the target value. Thereby, the recording density for each selected combination unit of nozzles becomes a value close to the target value, and density unevenness can be reduced.

US Pat. No. 7,249,815

  However, when using a recording head in which a plurality of recording element groups each having different recording elements are arranged and overlapping a part of the recording elements, the recording element selection for combination is performed in the overlapping area portion. There is a problem that becomes complicated. That is, there are recording elements to be selected for combination for each dot size for each recording element group, and there may be a slight difference in the size of dots to be recorded between the recording elements. In such a case, the process of determining which recording element group to select a recording element becomes complicated.

  The present invention provides a recording apparatus and a recording data generation method capable of reducing density unevenness by obtaining a combination of recording elements having different dot sizes to be recorded with respect to the recording elements in the overlapping region by a simple process. Objective.

  Therefore, the present invention is a recording head in which a plurality of recording element chips each having an array of recording element arrays are arranged such that some of the recording elements overlap along the arrangement direction. A recording apparatus for recording dots on a recording medium using a recording head including a plurality of types of recording elements having different dot sizes to be recorded on the recording medium, and recording along a direction perpendicular to the arrangement direction of the recording element arrays The size of dots to be recorded for each recording element group capable of recording a predetermined area corresponding to a recording element other than the overlapping recording element and a predetermined area corresponding to the overlapping recording element. Recording characteristic acquisition means for acquiring recording characteristic information on the recording element, and in accordance with the recording characteristic information, a recording element other than the overlapping recording element and the overlapping recording element A distribution ratio determining means for determining a distribution ratio for distributing the recording data to recording elements having different dot sizes to be recorded, and distribution with the distribution ratio in the case of recording data corresponding to the overlapping recording elements. And a sorting unit that sorts which recording element chip records the recording data of each recording element having a different dot size to be recorded.

  According to the above configuration, a plurality of printing element chips are arranged so that some printing elements overlap along the arrangement direction, and printing is performed using a printing head including printing elements having different dot sizes to be printed. Done. In this case, it is possible to obtain a combination of recording elements having different dot sizes to be recorded for the recording elements in the overlapping area by a simple process and reduce density unevenness.

1 is a diagram illustrating a schematic configuration of a recording apparatus according to an embodiment of the present invention. (A) And (b) is explanatory drawing which shows the detailed structure of the recording head of this embodiment. FIG. 3 is a block diagram illustrating a configuration of image processing in the recording apparatus according to the embodiment of the present invention. It is a flowchart which shows the process which determines the large and small dot distribution ratio which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the process which determines a large and small dot distribution ratio. (A)-(c) is a figure which shows the brightness distribution for every area | region measured in a large / small dot distribution ratio determination process. It is a flowchart which shows the recording data generation process which concerns on one Embodiment of this invention. (A) And (b) is a figure explaining an error diffusion process. It is a figure which shows the dot arrangement pattern corresponding to 5-value image data. It is a figure which shows the image data in each process of the process shown in FIG. It is a figure explaining a large and small dot distribution pattern when the large dot distribution ratio is 50%, that is, when the large and small dot distribution ratio is {large: small} = {1: 1}. (A)-(c) is a figure explaining the connection mask process which concerns on this embodiment. It is a figure explaining the detail of the mask process in a connection area | region. It is a figure which shows the mask set applicable to 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
(First embodiment)
<Outline of line printer>
FIG. 1 is a diagram showing a schematic configuration of a recording apparatus A1 according to an embodiment of the present invention. The recording apparatus A1 is an ink jet line printer, and includes a control unit A2, ink cartridges A61 to A64, a recording head A7, a recording medium transport mechanism A8, and the like. The ink cartridges A61 to A64 correspond to inks representing cyan, magenta, yellow, and black colors.

  The recording head A7 is a line head type recording head in which a plurality of nozzles as recording elements are arranged in the width direction of the recording medium to be conveyed. Each nozzle ejects ink by a thermal method. Each ink in the ink cartridges A61 to A64 is supplied to each nozzle of the recording head through the ink introduction pipes A61a to A64a, and ink is ejected from these nozzles to perform recording on the recording medium A100. Details of the recording head A7 will be described with reference to FIG.

  The recording medium transport mechanism A8 includes a paper feed motor A81 and a paper feed roller A82. The paper feed motor A81 rotates the paper feed roller A82 to transport the recording medium A100 to the position of the recording head A7 in the direction orthogonal to the paper feed roller A82.

  The control unit A2 includes a CPU (A3), a RAM (A41), and a ROM (A42), and controls operations of the recording head A7 and the paper feed roller A81 described above. The CPU (A3) develops the control program stored in the ROM (A42) in the RAM (A41) and executes it. Thus, various processes are performed on the image to be described later, and image data to be recorded by the recording head A7, control of the recording medium transport mechanism A8, and the like are performed.

  2A and 2B are explanatory views showing a detailed configuration of the recording head A7 according to the embodiment of the present invention. FIG. 2A shows an arrangement of a plurality of recording element chips, and FIG. (B) shows the nozzle arrangement in one printing element chip.

  As shown in FIG. 2A, the recording head A7 of this embodiment is configured so that some nozzles (recording elements) overlap between four recording element chips A71, A72, A73, and A74 adjacent to each other. It is an arrangement. Each of these recording element chips is provided with four nozzle rows as shown in FIG. A recording element chip A71 representatively shown as one recording element chip includes nozzle arrays A71a, A71b, A71c, and A71d, each of which includes two types of nozzles (a plurality of types of recording elements) with different volumes of ejected ink droplets. . The nozzle arrays A71a and A71c are each arranged with nozzles that eject relatively large volumes of ink droplets, and the nozzle arrays A71b and A71d are each composed of nozzles that eject relatively small volumes of ink droplets. is there. With this nozzle configuration, in the present embodiment, recording can be performed by forming dots of two types of sizes.

  Note that the number of nozzle rows with different dot sizes to be recorded is not limited to this, and may be one row, for example. Further, the nozzle unit of different dot sizes is not limited to the nozzle row, and may be a nozzle group unit having a two-dimensional arrangement such as a staggered arrangement or a unit for each nozzle. The recording head A7 of the present embodiment is a thermal recording head. However, the recording head A7 is not limited to this, and a plurality of recording element chips are arranged in a direction orthogonal to the transport direction, and a plurality of dots of the same size are arranged. Any line head that forms a raster and records image data may be used. For example, an ink jet recording head of another ink discharge method such as a piezo method may be used. Here, in the present embodiment, the volume of the ejected ink droplet relates to the recording characteristics such as the recording density depending on the size of the dots to be formed. In this respect, the application of the present invention is not limited to a printing element array in which printing elements having different volumes of ejected ink droplets are arranged. For example, it can be recording characteristic information that affects the dot size to be recorded, such as the ink droplet ejection speed. Further, the ink color may be an ink other than the above-described CMYK.

  In the following description, the dot diameter recorded on the recording medium by the ink ejected from the nozzles of the nozzle array is classified into two types of relatively large and small, and the nozzle array having a relatively large dot diameter is “ The “large nozzle row” and the relatively small nozzle row are called “small nozzle rows”. A dot having a relatively large dot diameter is referred to as a “large dot”, and a relatively small dot is referred to as a “small dot”. These are collectively referred to as a “large / small dot”.

<Large and small dot distribution ratio determination processing>
FIG. 3 is a block diagram showing a configuration of image processing in the recording apparatus according to the embodiment of the present invention, and FIG. 4 is a flowchart showing processing for determining a large / small dot distribution ratio according to the first embodiment of the present invention. It is. FIG. 5 is a diagram illustrating an example of processing for determining the large / small dot distribution ratio, and FIGS. 6A to 6C illustrate the lightness distribution for each region measured in the large / small dot distribution ratio determination processing. FIG. In the following, the process for determining the large / small dot distribution ratio will be described along the flowchart shown in FIG. 4 and with reference to FIGS. 3, 5 and 6 as necessary.

  In FIG. 4, first, in step D01, the correction target value setting unit A51 (FIG. 3) sets a correction target value. In this embodiment, as will be described later, the correction target value is managed by the brightness when printing is performed by adjusting the large / small dot distribution ratio so that the ink amount per unit area becomes a desired value.

  Next, in step D02, each of the recording element chips A71 to A74 has a large nozzle and a small nozzle for each nozzle group (recording element group) capable of recording a predetermined area along the direction perpendicular to the nozzle row on the recording medium. Record the recording characteristic acquisition pattern. Specifically, in FIG. 5, a recording characteristic acquisition pattern is recorded for each nozzle group (hereinafter, also referred to as a predetermined nozzle group) corresponding to each of regions 1 to 3 divided by a broken line. The predetermined nozzle group is composed of large nozzles A71a and A71c and small nozzles A71b and A71d in the recording element chip A71, and is composed of large nozzles A72a and A72c and small nozzles A72b and A72d in the recording element chip A72. Although part of the illustration is omitted in FIG. 5, the regions 1 to 3 correspond to eight nozzles arranged at an interval of 1200 dpi in the nozzle row arrangement direction.

  As shown in FIG. 5, the recording characteristic acquisition pattern is a pattern in which the distribution ratio of large dots is changed to 33%, 50%, and 67% for each predetermined nozzle group. Of the areas 1 to 3, the area 3 is an area in which the nozzles of the printing element chip A71 and the printing element chip A72 are overlapped. The recording characteristic acquisition pattern in this area is recorded by using the nozzles determined by the same used nozzle distribution process as described later with reference to FIG.

  Next, in step D03, the recording characteristic acquisition pattern recorded as described above is read by a scanner, and the brightness of each pattern is acquired.

  In step D04, the brightness of each recording characteristic acquisition pattern is compared with the brightness set as the correction target value for each region, and a distribution ratio indicating a value close to the correction target value is calculated.

  FIGS. 6A, 6B, and 6C show an example of the relationship between the brightness of the pattern corresponding to the large dot distribution ratio acquired for each region shown in FIG. 5 and the correction target value of the brightness. FIG. In the example shown in the figure, FIGS. 6A, 6 </ b> B, and 6 </ b> C respectively show the brightness obtained for the regions 2, 3, and 1. That is, as shown in FIG. 6C, the brightness of these patterns is corrected when the large dot distribution ratio of the nozzle group in the region 1 recorded by only the recording head A71 is 33%, 50%, and 67%. The large dot distribution ratio close to the target value is 67%. Similarly, as shown in FIG. 6A, when the large dot distribution ratio of the nozzle group in the area 2 recorded by only the recording head A72 is 33%, 50% and 67%, the brightness of these patterns is as follows. The large dot distribution ratio close to the correction target value is 33%.

  Unlike the above regions 1 and 2, the region 3 recorded by the overlapping nozzles of the two recording element chips A71 and A72 is the region where the nozzles overlap between the two recording element chips as described above. The recording characteristic acquisition pattern is recorded by the nozzles determined by the same nozzle allocation as in recording. In other words, the determination of the distribution ratio of the large and small dots based on the brightness obtained from the recording characteristic acquisition pattern of the region 3 is performed without distinguishing the recording element chip A71 and the recording element chip A72 for the large and small nozzles. Specifically, the large dot nozzles (A71a, A71c) of the recording element chip A71 and the large dot nozzles (A72a, A72c) of the recording element chip A72 are combined to form a “large dot nozzle” and a small dot nozzle ( A71b, A71d) and the small dot nozzles (A72b, A72d) of the recording element chip A72 are combined and handled as “small dot nozzles”. In the example shown in FIG. 6B, when the large dot distribution ratio is 33%, 50%, and 67%, the large dot distribution ratio at which the brightness of these patterns is close to the correction target value is 50%.

  Next, in step D05, the large / small dot distribution ratio derived in step D04 is set for each predetermined nozzle group. That is, in the example shown in FIGS. 6A, 6B, and 6C, area 1 has a large dot distribution ratio of 67% and small dot distribution ratio of 33%, and area 2 has a large dot distribution ratio of 33% and small dot distribution. The ratio 67% and the area 3 are set to a large dot distribution ratio 50% and a small dot distribution ratio 50%. The distribution ratio of the large and small dots for each of the areas set in this way is as follows when the print data generation described later with reference to FIG. 7 is performed. The non-overlapping area of the printing element chip A71, the non-overlapping area of the printing element chip A72, and These are used in correspondence with the overlapping regions of the chips. In particular, in the overlap area, the large and small dots are distributed based on the distribution ratio of the large and small dots obtained as described above without distinguishing the printing element chips. Then, the same dot distribution process (joint mask process) as that at the time of recording, the details of which will be described later with reference to FIGS. 12 and 13, is performed, and it is determined which nozzle of the printing element chip is used for the overlapping area.

  As described above, according to the embodiment of the present invention, even in an overlapping area of a plurality of printing element chips, a large and small dot distribution ratio can be obtained by the same process as a non-overlapping area (area corresponding to printing elements other than overlapping printing elements). Can be determined.

  It should be noted that the number of nozzles included in the predetermined nozzle group may be a number that can record a pattern having a size that can be read by the scanner and the brightness can be derived. Further, the large dot distribution ratio interval of the pattern may be an interval sufficient to properly derive the large and small dot distribution ratios.

<Recording data generation>
FIG. 7 is a flowchart showing recording data generation processing according to an embodiment of the present invention. Specifically, the processing shown in FIG. 7 is expressed by the presence or absence of dots by the recording apparatus A1 of the present embodiment performing predetermined image processing on the image data stored in the memory card A91 (FIG. 1). FIG. 6 shows a process of recording by converting into dot data (recording data).

  When the recording process is started, first, in step D11, the control unit A2 (FIG. 1) acquires image data to be recorded from the memory card A91 using the image input unit A31 (FIG. 3). Here, the image data is a color image having a resolution of 600 dpi and 8 bits for each RGB and 256 gradations. Of course, the application of the present invention can be similarly applied to a monochrome image regardless of a color image.

  Next, in step D12, the color conversion processing unit A32 (FIG. 3) performs color conversion processing, and converts the image data into 600 dpi, 8-bit 256-tone image data for each color of CMYK. As described above, the recording apparatus A1 records an image using four color inks of C, M, Y, and K. For this reason, the color conversion processing unit of the present embodiment converts image data expressed in RGB into image data expressed by gradation values of C, M, Y, and K colors.

  In the next step D13, the quantization processing unit A33 (FIG. 3) performs quantization processing. This quantization process is a process for converting image data having a large number of gradations such as 8-bit 256 gradations into lower gradations (here, five values will be described as an example) that can be recorded by the recording apparatus A1. is there. In general, an error diffusion method or a dither method is often used as the quantization processing. In the present embodiment, the error diffusion method will be described as an example.

  FIGS. 8A and 8B are diagrams for explaining the error diffusion processing. FIG. 8A shows the error diffusion processing as an arithmetic circuit. FIG. 8B shows a threshold (threshold). ), An output level (Out), and an evaluation value (Evaluation). In the multi-value error diffusion process in the case of quantization to five values, first, the corrected density value (In + dIn) is obtained by adding the image density value (In) and the diffusion error value (dIn) from the surrounding pixels. The comparator compares the obtained corrected density value (In + dIn) with a threshold value (threshold), and outputs an output level (Out) determined by the threshold value according to the value of the corrected density value. According to the relationship shown in FIG. 8B, if the correction density value (In + dIn) is “32 or less”, the output Level (Out) is “Level 0”, and if it is “greater than 32 and 96 or less”, the output is output. Level (Out) outputs “Level 1”. Next, a multi-value error (Error = In + dIn−Evaluation) obtained by subtracting the evaluation value (Evaluation) from the corrected density value (In + dIn) is calculated, and a weighting operation is performed to diffuse this multi-value error to surrounding pixels. And add to error buffer. Here, the relationship between the output level (Out) and the evaluation value (Evaluation) follows FIG. 8B. When the output Level (Out) is “Level4”, the evaluation value (Evaluation) is “255”, “Level3”. In the case of “192”, “Level2” is “128”, “Level1” is “64”, and “Level0” is “0”. Finally, the error value diffused to the target pixel position is taken out from the error buffer, normalized by the sum of the weight coefficients, and set as the diffusion error (dIn) of the next pixel. The above process is repeated for all pixels. As described above, 8-bit 256-gradation image data is quantized into 5-gradation image data.

  Next, in step D14, the dot recording position determination unit A34 (FIG. 3) determines the recording dot arrangement in the pixel based on the image data quantized to low gradation in pixel units. FIG. 9 is a diagram showing a dot arrangement pattern corresponding to five values “Level” “0” to “4”. In addition, the illustration of the dot arrangement of Level “0” (no dot exists in all pixels) is omitted. The pixel density of the five-valued image data to be quantized is 600 dpi, and when dot data is generated from this image data using the dot arrangement pattern shown in FIG. 9, the recording dot resolution is 1200 dpi. For example, if the result after quantization is Level “1”, only one dot is recorded in a 1200 × 4 4 × 4 pixel, and the dot recording position is “upper left (FIG. 9A)”, “lower left ( FIG. 9B) ”,“ Lower right (FIG. 9C) ”,“ Upper right (FIG. 9D) ”, and these arrangements are used repeatedly.

  Next, in step D15, the recording dot distribution processing unit A35 (FIG. 3) uses the large / small dot distribution ratio information set in advance as described above with reference to FIG. 4 by the large / small dot distribution ratio determining unit A53 (FIG. 3). Store in the large and small dot distribution pattern storage unit A41. Then, in the process of step D15, the recording dot distribution processing unit A35 receives the large / small dot distribution ratio information corresponding to the nozzle position for recording the recording dots from the large / small dot distribution pattern storage unit A41. Then, by using the large / small dot distribution pattern based on the large / small dot distribution ratio, it is determined for each dot position determined in step D14 in FIG. 7 whether the dot is a large dot or a small dot.

  10A to 10I are diagrams showing data in each step of the process shown in FIG. FIG. 10A shows the image data read in step D11. In this example, it is assumed that the data has gradation values of {R, G, B} = {192, 192, 192}. Next, FIG. 10B shows C image data among the ink {C, M, Y, K} color image data converted in step D12. As an example, the C signal value in the image data is {C} = {64}. Next, FIG. 10C is image data indicated by level values resulting from quantization into five values in step D13. As described above with reference to FIG. 8, the signal value {C} = {64} is converted into {C} = {Level 1} by error diffusion processing. Next, FIG.10 (d) has shown the process result of step D14. That is, using the dot arrangement pattern shown in FIG. 9, the Level 1 gradation value is converted into data indicating the presence or absence of a dot for each 1200 dpi pixel position.

  Next, in step D15, the dot size to be recorded for each dot position (in this embodiment, the ejection amount is 3 ng and 2 ng) is determined. In step D15, a large / small dot distribution pattern is acquired from a large / small dot distribution ratio obtained in advance for a predetermined nozzle group to be recorded. Then, this large / small dot pattern is applied to each dot shown in FIG. 10D to determine whether the dot is a large dot or a small dot.

  FIG. 11 is a diagram for explaining a large / small dot distribution pattern of each level after quantization when the large dot distribution ratio is 50%, that is, when the large / small dot distribution ratio is {large: small} = {1: 1}.

  11 (a-1) is Level 1, FIG. 11 (a-2) is Level 2, FIG. 11 (a-3) is Level 3, and FIG. 11 (a-4) is Level 4 using a large and small dot distribution pattern. Indicates the determined dot data. Among them, the dot data of Level 1 is as shown in FIG.

  In the following description, the process of determining whether to record dots in large or small will be described by taking the case of Level 1 shown in FIG. First, when the dot arrangement shown in FIG. 11 (a-1) is determined, next, the large / small dots corresponding to the large / small dot ratio (50%, 50% in the present embodiment) obtained in step D15 of FIG. Get distribution pattern. FIG. 11B-1 shows this size distribution pattern. In the figure, double circles mean distribution to large dots, and single circles mean distribution to small dots. By using this distribution pattern, each dot shown in FIG. 11 (a-1) refers to the same pixel position in the large / small distribution pattern shown in FIG. 11 (b-1), and has the size described in the pixel position. Replaced with dots.

  Through the above processing, when the distribution ratio of large and small dots is 50% and 50%, the Level 1 dot data shown in FIG. 10D is distributed to the large and small dot data shown in FIG. Similarly, the dot data of Level 2 is shown in FIG. 11 (b-2), the dot data of Level 3 is shown in FIG. 11 (b-3), and the dot data of Level 4 is shown in FIG. 11 (b-4). Are distributed to large and small dots respectively. In FIGS. 11B-1 to 11B-4, the distribution ratio of large dots to small dots (ratio of the number of large dots to small dots) is constant regardless of the quantization level. Accordingly, in the dot data distributed to large and small shown in FIG. 10E, the large dot (3 ng) and the small dot (2 ng) are distributed according to the calculated large / small distribution ratio 1: 1, and 3 ng and 2 ng Using the nozzle group, an average of 2.5 ng can be recorded per 600 dpi. FIGS. 10 (f-1) and (f-2) show the dot arrangement of large dots and the dot arrangement of small dots respectively extracted from the dot data distributed in large and small in FIG. 10 (e). . As can be seen from these figures, both have 8 dots.

  Referring to FIG. 7 again, next, in step D16, it is determined whether or not the generated dot data corresponds to a connection area. Here, when it is a non-connecting area | region, it progresses to step D18. In step D18, it is determined in which nozzle row the large and small dot data determined as described above are recorded. In this embodiment, since there are two large and small nozzle arrays, the large and small dot data shown in FIGS. 10F-1 and 10F-2 are divided into two using the nozzle array distribution pattern. FIGS. 10G-1 and 10G-2 illustrate the nozzle array distribution pattern according to this embodiment. As shown in FIGS. 10 (g-1) and 10 (g-2), in this embodiment, the nozzles are distributed to two large and small nozzle arrays, so that 50% of the dots are ON, and both are complementary. have.

  Specifically, FIG. 10G-1 shows a pattern distributed to the large dot nozzle rows A71a, A72a and the small dot nozzle rows A71b, A72b, and FIG. 10G-2 shows the large dot nozzle row A71c. , A72c and small dot nozzle rows A71d, A72d. By using these patterns, the print (dot) data of the nozzle row A 71a for printing large dots is the large dot data shown in FIG. 10 (f-1) and the nozzle row distribution pattern shown in FIG. 10 (g-1). Can be obtained by performing an AND operation. That is, data for large dots is generated only for pixels with “large dot: present” and “mask: ON”. FIG. 10 (h-1-1) shows the large dot data for the nozzle array A71a obtained in this way. Similarly, an AND operation is performed on the large dot data shown in FIG. 10 (f-1) and the nozzle distribution pattern shown in FIG. 10 (g-2) for the nozzle array A71c shown in FIG. 10 (h-1-2). Large dot data can be obtained. Similarly, for small dots, an AND operation is performed on the small dot data shown in FIG. 10 (f-2) and the nozzle distribution pattern shown in FIG. 10 (g-1). The small dot data for nozzle row A71b shown in FIG. Further, an AND operation is performed on the small dot data shown in FIG. 10 (f-2) and the nozzle distribution pattern shown in FIG. 10 (g-2), and for the nozzle row A71d shown in FIG. 10 (h-2-2). Small dot data can be obtained. In the present embodiment, the same nozzle row distribution pattern is used for both large and small recording dots, but they may be different from each other.

  Next, in step D19, the dot (recording) data of each nozzle array generated as described above is transferred to each of the nozzle arrays A71a to A71d and recorded on the recording medium. FIG. 10I is a diagram showing large and small dots recorded on the recording medium. In the figure, double circles indicate large dots and single circles indicate small dots. As is apparent from the figure, an image of 2.5 ng on average per 600 dpi is satisfied using {1: 1}, which is an example of the large / small dot distribution ratio in the above description, using a nozzle group of large: 3 ng and small: 2 ng. Recording is possible.

  Referring to FIG. 7 again, if it is determined in step D16 that the generated print data corresponds to a connection area, that is, an area where nozzles between the print element chips overlap, the process proceeds to step D17 to perform a connection mask process.

  FIGS. 12A to 12C are diagrams illustrating the connection mask process according to the present embodiment. The connection mask processing unit A37 shown in FIG. 3 performs the connection process.

  The dot arrangement shown in the center part of FIG. 12A represents dot arrangement data as a dot image on a recording medium, black circles indicate dot formation, and squares represent pixels on the recording medium. . In the example shown in FIG. 12A, dot data of a so-called solid image in which dots are recorded in all the pixels in the overlapping region (hereinafter referred to as a connecting region) of the recording element chips A71 and A72 is recorded on the recording element chip. This is an example of recording with nozzles A71 and A72.

  In this connection region, the recording element chips are distributed using a distribution mask pattern (hereinafter referred to as a mask) shown in FIG. The joining process is a process for performing a logical product (AND operation) of the mask shown in FIG. 12B and the dot data shown in FIG. 12A. The black grid and dot data in FIG. The dot data of each printing element chip can be obtained by taking the logical product with the dot data indicated by black circles in FIG. Specifically, the dot data of the recording element chip A 71 is obtained using the mask A shown in FIG. 12B, and the dot data of the recording element chip A 72 is obtained using the mask B. As a result, the dot data at the connecting portion of each printing element chip shown in FIG. In FIG. 12C, the left is dot data distributed to the recording element chip A71, and the right is dot data distributed to the recording element chip A72.

  FIG. 13 is a diagram for explaining the details of the dot distribution processing (connection mask processing) in the connection region in step D17 described above. FIG. 13A-1 shows the print data L_in distributed to the large dots when the large / small dot distribution ratio is 2 (67%): 1 (33%), and FIG. The recording data S_in distributed to the small dots in the ratio is shown. As shown in the figure, the mask processing unit A37 (FIG. 3) performs mask processing on these print data by taking a logical product with the connection masks A and B, respectively. By this processing, the recording data distributed to the large dots (A71a, A71c) of the recording element chip A71 shown in FIG. 13 (a-2) and the large size of the recording element chip A72 shown in FIG. 13 (a-3). Recording data distributed to the dots (A72a, A72c) is obtained. Further, the recording data distributed to the small dots (A71b, A71d) of the recording element chip A71 shown in FIG. 13B-2, and the small dots (A) of the recording element chip A72 shown in FIG. Recording data distributed to A72b, A72d) is obtained.

  Next, in step D18 of FIG. 7, in the same way as in the case of the non-overlapping area described above, it is determined in which nozzle row the large and small dot data is printed for each of the printing element chips A71 and A72. In the case of the overlapping region, the large and small dot data shown in FIGS. 13A-2, (A-3), (B-2), and (B-3) are each divided into two using the nozzle array distribution pattern. Note that the same nozzle array distribution mask as the non-overlapping region is used.

  As described above, according to the present embodiment, it is possible to reduce density unevenness even in an overlapping region of a plurality of printing element chips by the same processing as that in a non-overlapping region.

(Second Embodiment)
In the first embodiment described above, as described above with reference to FIG. 12B and the like, there is one type of mask for distributing dot data to the two printing element chips. In this case, the mask is used depending on the position on the paper surface. The nozzle to be fixed is fixed. On the other hand, in this embodiment, as shown in FIG. 14, a plurality of mask sets are rotated and used according to the recording position on the paper. Thereby, the nozzle to be used can be disperse | distributed. In addition, a connection mask used for pattern recording for acquiring recording characteristics in the connection area is also used by rotating a mask set in the same manner as in normal recording. That is, since the recording head selected by the rotation of the mask set is switched, in the sorting process, a plurality of mask sets are provided, and the plurality of mask sets are rotated and used. At this time, in recording characteristic information acquisition, a recording characteristic acquisition pattern is recorded at least twice to acquire a plurality of recording characteristics, and an average value of the plurality of recording characteristics is acquired as recording characteristic information.

A1 Recording device A2 Control unit A7 Recording head A71-74 Recording element chip A71a, b, c, d Nozzle group A35 Recording dot distribution processing unit A36 Used nozzle row determination unit A37 Joint mask processing unit A53 Large / small dot distribution rate determination unit

Claims (5)

A recording head in which a plurality of recording element chips each having an array of recording element arrays are arranged such that some of the recording elements overlap in the direction of the arrangement, and each of the plurality of recording element chips records on a recording medium A recording apparatus that records dots on a recording medium using a recording head including a plurality of types of recording elements having different dot sizes,
Recording a predetermined area of the recording medium along a direction perpendicular to the arrangement direction of the recording element arrays, the predetermined area corresponding to the recording elements other than the overlapping recording elements and the predetermined area corresponding to the overlapping recording elements, respectively. For each possible recording element group, recording characteristic acquisition means for acquiring recording characteristic information relating to the size of dots to be recorded,
A distribution ratio for determining a distribution ratio for distributing recording data to recording elements other than the overlapping recording elements and recording elements having different dot sizes to be recorded in the overlapping recording elements according to the recording characteristic information A determination means;
In the case of the recording data corresponding to the overlapping recording element, the recording element of which recording element chip records the recording data of each recording element having a different recording dot size distributed at the distribution ratio. A sorting means for sorting;
A recording apparatus characterized by comprising:   The recording apparatus according to claim 1, wherein the recording characteristic information is brightness of a recording characteristic acquisition pattern recorded by a recording element group capable of recording a predetermined area of the recording medium.   The distribution unit includes a connection mask set for distributing image data to the plurality of recording element chips, and uses the same connection mask set for normal recording and recording of a recording characteristic acquisition pattern. The recording apparatus according to 1 or 2. The sorting means includes a plurality of mask sets, and rotates and uses the plurality of mask sets.
The recording characteristic acquisition means records a recording characteristic acquisition pattern at least twice or more to acquire a plurality of recording characteristics, and acquires an average value of the plurality of recording characteristics as the recording characteristic information;
The recording apparatus according to claim 1, wherein the recording apparatus is a recording apparatus. A recording head in which a plurality of recording element chips each having an array of recording element arrays are arranged such that some of the recording elements overlap in the direction of the arrangement, and each of the plurality of recording element chips records on a recording medium A recording data generation method for recording dots on a recording medium using a recording head including a plurality of types of recording elements having different dot sizes,
Recording a predetermined area of the recording medium along a direction perpendicular to the arrangement direction of the recording element arrays, the predetermined area corresponding to the recording elements other than the overlapping recording elements and the predetermined area corresponding to the overlapping recording elements, respectively. For each possible recording element group, a recording characteristic acquisition step for acquiring recording characteristic information regarding the size of dots to be recorded,
A distribution ratio for determining a distribution ratio for distributing recording data to recording elements other than the overlapping recording elements and recording elements having different dot sizes to be recorded in the overlapping recording elements according to the recording characteristic information A decision process;
In the case of the recording data corresponding to the overlapping recording element, the recording element of which recording element chip records the recording data of each recording element having a different recording dot size distributed at the distribution ratio. A sorting process for sorting;
A recording data generation method characterized by comprising:

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