Inkjet printer

Abstract

To suppress a printing quality from deteriorating.SOLUTION: A control device 60 of a printer 10 comprises: an intermediate distribution ratio creating part 73 that creates intermediate dot distribution-rate information in which a plurality of dot distribution ratios have an intermediate distribution ratio between a first distribution ratio and a second distribution ratio, on the basis of first dot distribution-ratio information in which the plurality of dot distribution ratios have the first distribution ratio and second dot distribution-ratio information in which the dot distribution ratios have the second distribution ratio; a dividing part 75 that divides an area of a vector-type object Pd11 of input data Pd1 into a first area AR11, a second area AR12 and an intermediate area AR13, in accordance with a thickness of the object Pd11; a first converting part 81 that converts the first area AR11 to printing data for printing on the basis of the first distribution ratio; a second converting part 82 that converts the second area AR12 to the printing data on the basis of the second distribution ratio; an intermediate converting part 83 that converts the intermediate area AR13 to the printing data on the basis of the intermediate distribution ratio; and a printing part 84 that performs printing on the basis of the printing data.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an inkjet printer. [Background technology]

[0002] For example, Patent Document 1 discloses a print processing device capable of ejecting ink in three sizes of dots: small, medium, and large. When the type of object to be printed is a character, this print processing device determines whether the character size is X points or less. If the character size is larger than X points, normal-size screen processing is performed and printing is carried out. If the character size is X points or less, small-size screen processing is performed and printing is carried out. The small-size screen processing uses a density setting that is shifted to a lower density side compared to the normal-size screen processing. This improves the readability of printed small-size characters.

[0003] For example, Patent Document 2 discloses a printing system that reduces the occurrence of broken thin lines when they are printed. When thin lines are present in the original data, this printing system changes the threshold value of the dither mask and performs halftone processing based on the dither mask with the changed threshold value. This increases the number of locations where dots are formed by ink ejection, thereby improving the continuity of thin lines. As a result, it is possible to reduce the occurrence of broken thin lines in the printed image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-306555 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-157998 Summary of the Invention [Problem to be solved by the invention]

[0005] In the print processing device disclosed in Patent Document 1, if different screen processing is performed depending on whether the character size of the character to be printed is large or small, there is a risk of print quality deteriorating at the boundary between the large and small characters. Also, in the print system disclosed in Patent Document 2, if halftone processing is performed based on a dither mask in which the threshold value is changed depending on whether the line to be printed is a thin line or not, there is a risk of print quality deteriorating at the boundary between the thin line and a non-thin line.

[0006] The present invention has been made in view of the above-mentioned problems, and its object is to provide an inkjet printer that can prevent a decrease in print quality. [Means for solving the problem]

[0007] An inkjet printer according to the present invention includes a support base that supports a medium, an ink head capable of ejecting ink in dots of multiple sizes, a movement mechanism that moves the medium supported by the support base and the ink head relatively, and a control device. The control device includes a first acquisition unit, a second acquisition unit, an intermediate allocation ratio creation unit, an acquisition unit, a division unit, a first conversion unit, a second conversion unit, an intermediate conversion unit, and a printing unit. The first acquisition unit acquires first dot allocation ratio information in which the allocation ratio of ink to dots of multiple sizes is indicated by a first allocation ratio according to a gradient. The second acquisition unit acquires second dot allocation ratio information in which the allocation ratio of ink to dots of multiple sizes is indicated by a second allocation ratio that increases the allocation ratio of ink to smaller dots compared to the first allocation ratio. The intermediate allocation ratio creation unit creates intermediate dot allocation ratio information in which the allocation ratio of ink to dots of multiple sizes is indicated by an intermediate allocation ratio between the first allocation rate and the second allocation rate, based on the first dot allocation rate information and the second dot allocation rate information. The acquisition unit acquires printable input data including at least a vector-format object. The division unit divides a region of the vector-format object in the input data into a first region where the thickness of the vector-format object is greater than a first thickness, a second region where the thickness of the vector-format object is smaller than a second thickness that is smaller than the first thickness, and an intermediate region where the thickness of the vector-format object is less than the first thickness and greater than or equal to the second thickness. The first conversion unit converts the first region of the vector-format object into print data for printing based on the first allocation ratio. The second conversion unit converts the second region of the vector-format object into the print data based on the second allocation ratio. The intermediate conversion unit converts the intermediate region of the vector-format object into the print data based on the intermediate allocation ratio. The printing unit performs printing by ejecting ink dots of multiple sizes based on the print data converted by the first conversion unit, the second conversion unit, and the intermediate conversion unit.

[0008] According to the inkjet printer, intermediate dot allocation rate information used for an intermediate region between the first and second regions is created based on first dot allocation rate information used for a first region of a vector-format object that is larger than the first thickness, and second dot allocation rate information used for a second region of a vector-format object that is smaller than the second thickness. Therefore, when printing based on print data obtained by converting the intermediate region of the vector-format object, multiple dots of ink are ejected at an intermediate allocation rate between the first and second allocation rates, thereby reducing printing differences at the boundaries between the first and intermediate regions and between the intermediate and second regions compared to conventional methods. Therefore, by printing based on print data obtained by converting input data using the intermediate dot allocation rate information in addition to the first and second dot allocation rate information, degradation in print quality can be suppressed.

[0009] Another inkjet printer according to the present invention includes a support base that supports a medium, an ink head capable of ejecting ink in dots of multiple sizes, a movement mechanism that moves the medium supported by the support base and the ink head relatively, and a control device. The control device includes a first acquisition unit, a second acquisition unit, an intermediate allocation ratio creation unit, an acquisition unit, an edge detection unit, a distance calculation unit, a division unit, a first conversion unit, a second conversion unit, an intermediate conversion unit, and a printing unit. The first acquisition unit acquires first dot allocation ratio information in which the allocation ratio of ink to dots of multiple sizes is indicated by a first allocation ratio according to a gradient. The second acquisition unit acquires second dot allocation ratio information in which the allocation ratio of ink to dots of multiple sizes is indicated by a second allocation ratio that has a higher allocation ratio for ink to smaller dots than the first allocation ratio. The intermediate allocation ratio creation unit creates intermediate dot allocation ratio information indicating the allocation ratios of ink to dots of multiple sizes at an intermediate allocation ratio between the first allocation ratio and the second allocation ratio based on the first dot allocation ratio information and the second dot allocation ratio information. The acquisition unit acquires printable input data including at least an object. The edge detection unit detects edges of the object in the input data. The distance calculation unit calculates the edge-to-edge distance of the object based on the edges of the object detected by the edge detection unit. The division unit divides a region of the object in the input data into a first region where the edge-to-edge distance is greater than a first distance, a second region where the edge-to-edge distance is less than a second distance that is smaller than the first distance, and an intermediate region where the edge-to-edge distance is less than the first distance and greater than or equal to the second distance. The first conversion unit converts the first region of the object into print data for printing based on the first allocation ratio. The second conversion unit converts the second region of the object into print data based on the second allocation ratio. The intermediate conversion unit converts the intermediate area of ​​the object into the print data based on the intermediate allocation ratio, and the printing unit performs printing by ejecting ink in dots of multiple sizes based on the print data converted by the first conversion unit, the second conversion unit, and the intermediate conversion unit.

[0010] According to the other inkjet printers described above, the object included in the input data may not include thickness (e.g., width) information. However, here, by detecting edges of the object in the input data and calculating the edge-to-edge distance, the thickness of the lines and other components of the object can be calculated as the edge-to-edge distance. Therefore, an area of ​​the object where the edge-to-edge distance is less than a first distance and greater than a second distance is defined as an intermediate area. When printing based on print data obtained by converting the intermediate area of ​​the object, multiple dots of ink are ejected at an intermediate allocation rate between the first and second allocation rates. Therefore, compared to conventional printers, the printing difference between the object at the boundary between the first and intermediate areas and the object at the boundary between the intermediate and second areas can be reduced. As a result, by printing based on print data obtained by converting input data using intermediate dot allocation rate information in addition to the first and second dot allocation rate information, degradation of print quality can be suppressed. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an inkjet printer that can prevent a decrease in print quality. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a front view showing a printer according to an embodiment. [Figure 2] FIG. 2 is a bottom view schematically illustrating the configuration of the bottom of the printer carriage and ink head. [Figure 3] FIG. 1 is a block diagram of a printer according to an embodiment. [Figure 4] 3 is a schematic diagram showing inks for first dots, second dots, and third dots that can be ejected from an ink head. FIG. [Figure 5] FIG. 10 is a diagram illustrating an example of input data. [Figure 6] 10 is a graph showing first dot allocation ratio information. [Figure 7]10 is a graph showing second dot allocation rate information. [Figure 8] FIG. 10 is a diagram showing lines of an object in vector format in input data. [Figure 9] FIG. 10 is a diagram showing vector format object characters in input data. [Figure 10] 10 is a flowchart illustrating print control for a vector-format object in input data. [Figure 11] 10 is a graph showing intermediate dot allocation rate information. [Figure 12] FIG. 10 is a diagram showing raster objects in input data. [Figure 13] 10 is a flowchart illustrating print control for a raster format object of input data. [Figure 14] FIG. 10 illustrates an object in raster format after edges have been detected. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of an inkjet printer according to the present invention will be described with reference to the drawings. It should be noted that the embodiment described here is not intended to limit the present invention in any particular way. Furthermore, the same reference numerals are used to designate components and parts that perform the same functions, and redundant descriptions will be omitted or simplified as appropriate.

[0014] An inkjet printer (hereinafter simply referred to as the printer) 10 according to this embodiment will be described below. FIG. 1 is a front view of the printer 10 according to this embodiment. FIG. 2 is a bottom view schematically illustrating the configuration of the bottom of the carriage 17 and ink head 20 of the printer 10. FIG. 3 is a block diagram of the printer 10 according to this embodiment. Here, the symbols F, Rr, L, R, U, and D in the drawings represent the front, rear, left, right, top, and bottom of the printer 10, respectively. The symbol Y in the drawings indicates the main scanning direction. In this embodiment, the main scanning direction Y is the left-right direction. The symbol X in the drawings indicates the sub-scanning direction. In this embodiment, the sub-scanning direction X is the front-to-back direction, and is a direction that intersects (here, perpendicular to) the main scanning direction Y in a plan view. However, these directions are merely defined for convenience of explanation and do not limit the installation mode of the printer 10 or the present invention in any way.

[0015] Printer 10 prints on medium 5 shown in FIG. 1. Medium 5 is, for example, rolled recording paper, commonly known as roll paper. However, medium 5 is not limited to rolled recording paper. For example, medium 5 may be paper such as plain paper or inkjet printing paper, or may be a sheet or film made of resin such as polyvinyl chloride or polyester, a plate, a fabric such as woven fabric or nonwoven fabric, or other medium.

[0016] Printer 10 is an inkjet printer. In this embodiment, printer 10 is a so-called roll-to-roll type printer that moves a roll-shaped medium 5 in the sub-scanning direction X. However, printer 10 may also be a so-called flatbed type printer in which a support base 13 (see FIG. 1), which will be described later, moves in the sub-scanning direction X, thereby moving the medium 5 in the sub-scanning direction X. Printer 10 may also be a so-called gantry type printer in which an ink head 20 (see FIG. 2), which will be described later, moves in the main scanning direction Y and the sub-scanning direction X, without moving the medium 5 itself supported by support base 13.

[0017] As shown in FIG. 1, the printer 10 includes a printer body 11, a support base 13, guide rails 15, a carriage 17, an ink head 20 (see FIG. 2), a moving mechanism 30, an operation panel 50, and a control device 60.

[0018] The printer body 11 has a casing that extends in the main scanning direction Y. The printer body 11 is supported by legs 12. The legs 12 are provided on the bottom surface of the printer body 11 and extend downward from the bottom surface.

[0019] The support table 13 supports the medium 5. Here, the upper surface of the support table 13 extends in the main scanning direction Y and the sub-scanning direction X. The medium 5 is placed on the upper surface of the support table 13. Printing is performed on the medium 5 on the support table 13.

[0020] The guide rail 15 is disposed above the support base 13. The guide rail 15 is disposed parallel to the upper surface of the support base 13 and extends in the main scanning direction Y. A carriage 17 is engaged with the guide rail 15. The carriage 17 is slidably engaged with the guide rail 15 and is configured to be movable in the main scanning direction Y along the guide rail 15.

[0021] As shown in FIG. 2, the ink heads 20 are mounted on the carriage 17. Here, the ink heads 20 are supported by the carriage 17 so that their undersides (here, nozzle surfaces 25, described below) are exposed. There is no particular limitation on the number of ink heads 20. In this embodiment, there are four ink heads 20. The four ink heads 20 are arranged side by side in the main scanning direction Y. The ink heads 20 are configured to be movable in the main scanning direction Y along the guide rails 15 together with the carriage 17.

[0022] Each ink head 20 has a nozzle surface 25. The nozzle surface 25 forms the bottom surface of the ink head 20. Nozzles 26 are formed in each nozzle surface 25. A plurality of nozzles 26 are formed in the nozzle surface 25, and are arranged side by side in the sub-scanning direction X. Here, a row of nozzles 26 arranged in the sub-scanning direction X on the nozzle surface 25 is referred to as a nozzle row 27. Here, the number of nozzle rows 27 on one nozzle surface 25 is two. However, the number of nozzle rows 27 on one nozzle surface 25 may be one, or three or more.

[0023] In this embodiment, different color inks are ejected from the nozzles 26 of each nozzle row 27 of the ink head 20. The inks ejected from the nozzles 26 of the ink head 20 are, for example, process color inks or special color inks. Process color inks include, for example, cyan ink, magenta ink, yellow ink, and black ink. Special color inks are inks of colors other than the process color inks. Special color inks include, for example, primer ink, white ink, clear ink, gloss ink, fluorescent ink, metallic ink, orange ink, red ink, violet ink, blue ink, and green ink.

[0024] 1, the movement mechanism 30 is a mechanism for relatively moving the medium 5 supported by the support base 13 and the ink head 20 (for example, a mechanism for moving in three dimensions). The configuration of the movement mechanism 30 is not particularly limited. Here, the movement mechanism 30 has a head movement mechanism 40 and a medium movement mechanism 45.

[0025] The head moving mechanism 40 moves the ink head 20 (see FIG. 2) in the main scanning direction Y relative to the medium 5 supported by the support base 13. In this embodiment, the head moving mechanism 40 moves the ink head 20 and the carriage 17 in the main scanning direction Y. The configuration of the head moving mechanism 40 is not particularly limited. As shown in FIG. 1, the head moving mechanism 40 includes left and right pulleys 41a and 41b, a belt 42, and a scan motor 43. The left pulley 41a is provided around the left end of the guide rail 15. The right pulley 41b is provided around the right end of the guide rail 15. The belt 42 is an endless belt that is wound around the left and right pulleys 41a and 41b. The carriage 17 is fixedly attached to the belt 42. The scan motor 43 is connected to the right pulley 41b.

[0026] Here, when the scan motor 43 is driven, the right pulley 41b rotates and the belt 42 moves, whereby the carriage 17 and the ink head 20 move in the main scanning direction Y along the guide rail 15.

[0027] The medium moving mechanism 45 moves the medium 5 supported by the support base 13 in the sub-scanning direction X relative to the ink head 20. In this embodiment, the medium moving mechanism 45 moves the medium 5 supported by the support base 13 in the sub-scanning direction X. The configuration of the medium moving mechanism 45 is not particularly limited. Here, the medium moving mechanism 45 includes a pinch roller 46, a grit roller 47, and a feed motor 48. The pinch roller 46 is provided above the support base 13 and below the guide rail 15, and presses down on the medium 5 from above. The pinch roller 46 is located behind the carriage 17 in a plan view. The grit roller 47 is provided on the support base 13 and is a member with a cylindrical outer periphery. The grit roller 47 is embedded in the support base 13 with its upper surface exposed. The grit roller 47 faces the pinch roller 46. The feed motor 48 is connected to the grit roller 47.

[0028] When the feed motor 48 is driven while the medium 5 is sandwiched between the pinch roller 46 and the grit roller 47, the grit roller 47 rotates, thereby transporting the medium 5 supported by the support base 13 in the sub-scanning direction X.

[0029] 1, in this embodiment, the operation panel 50 is provided on the right end of the printer body 11. The operation panel 50 is provided with a display screen 51 that displays the status of the printer 10, and input keys 52 that are operated by the user.

[0030] The control device 60 is a device that performs control related to printing, etc. The configuration of the control device 60 is not particularly limited. The control device 60 is, for example, a microcomputer. The hardware configuration of the microcomputer is not particularly limited. The control device 60 includes, for example, an I / F, a CPU, a ROM, and a RAM. The control device 60 is provided inside the printer main body 11. However, the control device 60 may also be realized by a computer or the like installed outside the printer main body 11. In this case, the control device 60 is connected to a control board (not shown) of the printer 10 via a wired or wireless connection so as to be able to communicate with it.

[0031] 3, the control device 60 is communicatively connected to the ink head 20, the head moving mechanism 40 (more specifically, the scan motor 43) of the moving mechanism 30, the medium moving mechanism 45 (more specifically, the feed motor 48) of the moving mechanism 30, and the operation panel 50 (more specifically, the display screen 51 and the input keys 52). The control device 60 controls the ink head 20, the head moving mechanism 40, the medium moving mechanism 45, and the operation panel 50.

[0032] FIG. 4 is a schematic diagram showing ink dots Dt1 that can be ejected by the ink head 20. In the printer 10 according to this embodiment, as shown in FIG. 4, ink dots Dt1 of multiple sizes are ejected from the ink head 20. Printing is performed on the medium 5 by gathering together ink dots Dt1 of multiple sizes. Note that there is no particular limit to the number of different sizes of ink dots Dt1 ejected by the ink head 20. In this embodiment, the ink head 20 is capable of ejecting ink dots Dt1 of three different diameters.

[0033] Here, the ink dot Dt1 ejected from the ink head 20 includes a first dot Dt11, a second dot Dt12, and a third dot Dt13. The first dot Dt11 is a so-called large dot and has a first diameter A11. The second dot Dt12 is a so-called medium dot and has a second diameter A12. Here, the second diameter A12 is smaller than the first diameter A11. The third dot Dt13 is a so-called small dot and has a third diameter A13. The third diameter A13 is smaller than the first diameter A11 and also smaller than the second diameter A12.

[0034] FIG. 5 is a diagram showing an example of input data Pd1. In the printer 10 according to this embodiment, the input data Pd1 shown in FIG. 5 is converted into print data, and printing is performed based on the converted print data. For example, printing based on the input data Pd1 is performed on the medium 5 by ejecting ink from the ink head 20 onto an area of ​​the medium 5 corresponding to an area in the input data Pd1 where a color is specified. The input data Pd1 is saved in, for example, a PDF (Portable Document Format) format. The input data Pd1 can be referred to as, for example, image data.

[0035] As shown in FIG. 5, the input data Pd1 includes objects. An object is a general term for anything that can be edited using so-called drawing and editing software. Objects include lines, characters, images, and the like. The objects include a vector-format object Pd11 and a raster-format object Pd12. Depending on the input data Pd1, either the vector-format object Pd11 or the raster-format object Pd12 may be placed, and the other may not be placed. The vector-format object Pd11 and the raster-format object Pd12 have different data formats. The vector-format object Pd11 is a data format that stores geometric information of the object (e.g., coordinate positions of points, line width, degree of curvature of the line, etc.). The raster-format object Pd12 is a data format that stores pixel values ​​of the object.

[0036] Here, the vector-format object Pd11 includes information about the thickness of the object Pd11 that has been set in advance, and is printed with a thickness corresponding to the thickness information. This thickness information includes information such as the width of the lines included in the vector-format object Pd11, the size of the characters, and the line width of the characters, and is specified in units such as points. Examples of the vector-format object Pd11 include a line Pd21 and a character Pd22. Here, the line Pd21 includes straight lines and curved lines. The width of the line Pd21 is the thickness of the vector-format object Pd11. The character Pd22 is drawn in a predetermined font and includes, for example, hiragana, katakana, kanji, alphanumeric characters, and symbols. The size of the character Pd22 is the thickness of the vector-format object Pd11.

[0037] The raster object Pd12 is the input data Pd1 minus the vector object Pd11. The raster object Pd12 is, for example, an image. Images include, for example, pictures, patterns, and photographs. Unlike the vector object Pd11, the raster object Pd12 does not include information about thickness expressed in units such as points. Therefore, it is not possible to directly determine which parts of the raster object Pd12 are thick and which parts are thin from the raster object Pd12.

[0038] 6 and 7 are graphs showing dot allocation ratio information R1. In this embodiment, the proportions at which the ink of the first dots Dt11, the ink of the second dots Dt12, and the ink of the third dots Dt13 are ejected in a predetermined area of ​​the input data Pd1 are determined based on the dot allocation ratio information R1 shown in FIGS.

[0039] Here, as shown in FIG. 6, for example, the dot allocation ratio information R1 specifies the allocation ratios of each of a plurality of sizes of dots (here, first dots Dt11 to third dots Dt13) according to the gradient of the input data Pd1. The dot allocation ratio information R1 is expressed, for example, as a table, and graphs of the dot allocation ratio information R1 are shown in FIGS. 6 and 7. In FIG. 6 and other figures, the horizontal axis represents the gradient of the input data Pd1, and the vertical axis represents the proportions (in other words, allocation ratios) of each of the first dots Dt11 to third dots Dt13. Ink for the first dots Dt11 to third dots Dt13 is ejected toward the medium 5 so that the allocation ratios correspond to the gradient of the input data Pd1, and printing is performed on the medium 5 based on the print data converted from the input data Pd1.

[0040] For example, the dot allocation ratio information R1 has first dot allocation ratio information R11 (see FIG. 6) and second dot allocation ratio information R12 (see FIG. 7). In this embodiment, as shown in FIG. 6, the first dot allocation ratio information R11 is information in which the ink allocation ratio of dots of multiple sizes (here, first dots Dt11 to third dots Dt13) is indicated by a first allocation ratio Rt1 according to the gradient. As shown in FIG. 7, the second dot allocation ratio information R12 is information in which the ink allocation ratio of dots of multiple sizes (here, first dots Dt11 to third dots Dt13) is indicated by a second allocation ratio Rt2 according to the gradient.

[0041] Here, the first allocation rate Rt1 and the second allocation rate Rt2 are different. The second allocation rate Rt2 has a higher allocation rate for ink of smaller dots than the first allocation rate Rt1. In this embodiment, in the second dot allocation rate information R12, the second allocation rate Rt2 has a higher allocation rate for ink of the second dots Dt12 and the third dots Dt13 than the first allocation rate Rt1. In the first dot allocation rate information R11, the first allocation rate Rt1 has a higher allocation rate for ink of the first dot Dt11 than the second allocation rate Rt2.

[0042] Conventionally, for example, when a vector-format object Pd11 in input data Pd1 is converted into print data and printed, thick objects Pd11 (for example, objects Pd11 that are equal to or thicker than a predetermined reference thickness) are printed based on first dot allocation rate information R11 (see FIG. 6), and thin objects Pd11 (for example, objects Pd11 that are thinner than the reference thickness) are printed based on second dot allocation rate information R12 (see FIG. 7). In other words, when printing thin objects Pd11, the ink allocation rates for the third dots Dt13 and the second dots Dt12 are higher than when printing thick objects Pd11.

[0043] However, as described above, if the input data Pd1 were converted into print data and printed using only the first and second dot allocation rate information R11 and R12, there would be a risk of print quality degradation due to differences in printing at the point where the first dot allocation rate information R11 and the second dot allocation rate information R12 switch, i.e., at the boundary between thicknesses equal to or greater than the reference thickness and thicknesses less than the reference thickness. Therefore, the printer 10 according to this embodiment controls printing so as to prevent degradation in print quality even when printing using multiple pieces of dot allocation rate information R1.

[0044] In this embodiment, as shown in FIG. 3, the control device 60 of the printer 10 includes a storage unit 61, a first acquisition unit 71, a second acquisition unit 72, an intermediate allocation rate creation unit 73, an acquisition unit 74, a division unit 75, a first conversion unit 81, a second conversion unit 82, an intermediate conversion unit 83, and a printing unit 84. The control device 60 also includes an image correction processing unit 91, an edge detection unit 92, and a distance calculation unit 93. Each of the units 61 to 93 constituting the control device 60 may be implemented by one or more processors or may be implemented by circuits. Each of the units 61 to 93 constituting the control device 60 may also be implemented by being programmed by predetermined software.

[0045] Next, the procedure for printing on a medium 5 based on input data Pd1A will be described. FIGS. 8 and 9 are diagrams showing a line Pd21A and a character Pd22A of a vector-format object Pd11A in the input data Pd1A, respectively. FIG. 10 is a flowchart showing print control for the vector-format object Pd11A of the input data Pd1A. Here, the procedure for printing on a medium 5 the vector-format object Pd11A of the input data Pd1A shown in FIGS. 8 and 9 will first be described with reference to the flowchart in FIG. 10.

[0046] 10, first, in step S101, the first acquisition unit 71 in FIG. 3 acquires the first dot allocation rate information R11 (see FIG. 6). For example, the first dot allocation rate information R11 is stored in advance in the storage unit 61. Here, the first acquisition unit 71 acquires the first dot allocation rate information R11 stored in the storage unit 61 from the storage unit 61. However, the first dot allocation rate information R11 does not have to be stored in the storage unit 61, and may be stored in an external device such as a personal computer communicatively connected to the printer 10. In this case, the first acquisition unit 71 may acquire the first dot allocation rate information R11 from the external device. The first dot allocation rate information R11 acquired from the external device may be stored in the storage unit 61.

[0047] Next, in step S103 of FIG. 10, the second acquisition unit 72 of FIG. 3 acquires the second dot allocation rate information R12 (see FIG. 7). Here, the second dot allocation rate information R12, like the first dot allocation rate information R11, is pre-stored in the storage unit 61. The second acquisition unit 72 acquires the second dot allocation rate information R12 stored in the storage unit 61 from the storage unit 61. However, the second dot allocation rate information R12 may also be stored in the external device communicatively connected to the printer 10. In this case, the second acquisition unit 72 may acquire the second dot allocation rate information R12 from the external device. The second dot allocation rate information R12 acquired from the external device may be stored in the storage unit 61.

[0048] Fig. 11 is a graph showing intermediate dot allocation rate information R13. Next, in step S105 of Fig. 10, the intermediate allocation rate creation unit 73 of Fig. 3 creates intermediate dot allocation rate information R13 as shown in Fig. 11. Here, the intermediate allocation rate creation unit 73 creates the intermediate dot allocation rate information R13 based on the first dot allocation rate information R11 (see Fig. 6) and the second dot allocation rate information R12 (see Fig. 7). Here, the intermediate dot allocation rate information R13 is information that indicates the ink allocation rates of dots of multiple sizes (here, first dots Dt11 to third dots Dt13) at an intermediate allocation rate Rt3 that is between the first allocation rate Rt1 (see Fig. 6) and the second allocation rate Rt2 (see Fig. 7). In the intermediate dot allocation rate information R13, in the gradation of the input data Pd1A, the allocation rate of the first dot Dt11 is between the first allocation rate Rt1 and the second allocation rate Rt2 of the first dot Dt11, the allocation rate of the second dot Dt12 is between the first allocation rate Rt1 and the second allocation rate Rt2 of the second dot Dt12, and the allocation rate of the third dot Dt13 is between the first allocation rate Rt1 and the second allocation rate Rt2 of the third dot Dt13.

[0049] In this embodiment, in the intermediate dot allocation rate information R13, the intermediate allocation rate Rt3 sets the ink allocation rate of the first dots Dt11 lower than the first allocation rate Rt1 and higher than the second allocation rate Rt2. The intermediate allocation rate Rt3 sets the ink allocation rate of the second dots Dt12 higher than the first allocation rate Rt1 and lower than the second allocation rate Rt2. The intermediate allocation rate Rt3 sets the ink allocation rate of the third dots Dt13 higher than the first allocation rate Rt1 and lower than the second allocation rate Rt2.

[0050] Note that the specific control by which the intermediate allocation rate creation unit 73 creates the intermediate dot allocation rate information R13 is not particularly limited, as long as it is created based on the first dot allocation rate information R11 and the second dot allocation rate information R12. In this embodiment, the intermediate allocation rate creation unit 73 creates the intermediate dot allocation rate information R13 using linear interpolation. Here, the intermediate allocation rate creation unit 73 creates the intermediate dot allocation rate information R13 by calculating the intermediate allocation rate Rt3 by linearly interpolating the first allocation rate Rt1 and the second allocation rate Rt2. Note that the intermediate dot allocation rate information R13 created by the intermediate allocation rate creation unit 73 is stored in the storage unit 61 of FIG. 3.

[0051] Next, in step S107 of FIG. 10, the acquisition unit 74 of FIG. 3 acquires input data Pd1A including at least an object Pd11A in a vector format as shown in FIGS. 8 and 9. The input data Pd1A is stored, for example, in an external device communicatively connected to the printer 10. For example, software for creating input data is installed in the external device. The external device creates and stores the input data Pd1A using the software for creating input data. The acquisition unit 74 of the printer 10 acquires the input data Pd1A from the external device communicatively connected to the printer 10. The input data Pd1A acquired from the external device is stored in the storage unit 61 of FIG. 3. Note that the input data Pd1A may be stored in advance in the storage unit 61. In this case, the acquisition unit 74 may acquire the input data Pd1A stored in advance in the storage unit 61.

[0052] Next, in step S109 of FIG. 10, the division unit 75 of FIG. 3 divides the vector-format object Pd11A of the input data Pd1A into a first region AR11, a second region AR12, and an intermediate region AR13, as shown in FIGS. 8 and 9. Here, the vector-format object Pd11A of the input data Pd1A is divided according to the thickness of the vector-format object Pd11A. In this embodiment, the region of the thick object Pd11A is defined as the first region AR11, and the region of the thin object Pd11A is defined as the second region AR12. The region of the vector-format object Pd11A between the thick object Pd11A and the thin object Pd11A is defined as the intermediate region AR13. Here, the intermediate region AR13 is the entire region of the vector-format object Pd11A excluding the first region AR11 and the second region AR12.

[0053] In this embodiment, the thickness of the object Pd11A in the vector format at the boundary between the first region AR11 and the intermediate region AR13 is a first thickness. That is, the dividing unit 75 defines the region of the object Pd11A in the vector format where the thickness of the object Pd11A is greater than the first thickness as the first region AR11. In FIGS. 8 and 9, a boundary line L11 is a line indicating the boundary between the first region AR11 and the intermediate region AR13. Here, the thickness of the object Pd11 in the vector format at the boundary between the intermediate region AR13 and the second region AR12 is a second thickness. The second thickness is smaller than the first thickness. The dividing unit 75 defines the region of the object Pd11A in the vector format where the thickness of the object Pd11A is smaller than the second thickness as the second region AR12. In FIGS. 8 and 9, a boundary line L12 is a line indicating the boundary between the intermediate region AR13 and the second region AR12. The dividing unit 75 defines the region of the object Pd11A in vector format where the thickness of the object Pd11A is equal to or smaller than the first thickness and equal to or larger than the second thickness as the intermediate region AR13.

[0054] Here, the thickness of the vector-format object Pd11A can be expressed in units of points. As shown in FIG. 8, for example, if the vector-format object Pd11A is a line Pd21A, the thickness of the vector-format object Pd11A refers to the width of the line Pd21A. In this case, the first thickness can be referred to as the first width. The second thickness can be referred to as the second width. The second width is a width smaller than the first width. The dividing unit 75 determines, within the region of the line Pd21A of the vector-format object Pd11A, a region where the width of the line Pd21A is greater than the first width as a first region AR11, and a region where the width of the line Pd21A is smaller than the second width as a second region AR12. The dividing unit 75 determines, within the region of the line Pd21A of the vector-format object Pd11A, a region where the width of the line Pd21A is equal to or smaller than the first width and equal to or larger than the second width as an intermediate region AR13.

[0055] In this embodiment, as shown in FIG. 9, when the object Pd11A in vector format is character Pd22A, the thickness of the object Pd11A in vector format refers to the size of the character Pd22A. The first thickness can be referred to as the first size. The second thickness can be referred to as the second size. The second size is a size smaller than the first size. The dividing unit 75 determines, within the region of the character Pd22A in the object Pd11A in vector format, a region where the size of the character Pd22A is larger than the first size as a first region AR11, and a region where the size of the character Pd22A is smaller than the second size as a second region AR12. The dividing unit 75 determines, within the region of the character Pd22A in the object Pd11A in vector format, a region where the size of the character Pd22A is equal to or smaller than the first size and equal to or larger than the second size as an intermediate region AR13.

[0056] As described above, after the dividing unit 75 divides the area of ​​the vector-format object Pd11A into the first area AR11, the second area AR12, and the intermediate area AR13, the process proceeds to step S111 in FIG. 10. In step S111, the vector-format object Pd11A of the input data Pd1A is converted into print data. In this embodiment, the input data Pd1A is converted into print data by performing RIP (Raster Image Processor) processing. Here, print data refers to data for printing, and is data that can be interpreted by the printer 10 itself. The print data refers to raster data or bitmap data obtained by RIP processing. RIP processing refers to rasterization processing, for example, and includes halftone processing, color conversion processing, etc.

[0057] In this embodiment, the first conversion unit 81 converts the first region AR11 of the vector-format object Pd11A into print data based on the first allocation rate Rt1 of the first dot allocation rate information R11 (see FIG. 6). Here, the first conversion unit 81 converts the first region AR11 into print data by performing RIP processing on it. The second conversion unit 82 converts the second region AR12 of the vector-format object Pd11A into print data based on the second allocation rate Rt2 of the second dot allocation rate information R12 (see FIG. 7). Here, the second conversion unit 82 converts the second region AR12 into print data by performing RIP processing on it. The intermediate conversion unit 83 converts the intermediate region AR13 of the vector-format object Pd11A into print data based on the intermediate allocation rate Rt3 of the intermediate dot allocation rate information R13 (see FIG. 11). Here, the intermediate conversion unit 83 converts the intermediate region AR13 into print data by performing RIP processing on it. Conversion to print data may be performed for each area, i.e., conversion to print data may be performed separately for the first area AR11, the second area AR12, and the intermediate area AR13. Conversion to print data may also be performed collectively for the first area AR11, the second area AR12, and the intermediate area AR13.

[0058] In this way, after the vector format object Pd11A of the input data Pd1A is converted into print data, in step S113 of FIG. 10, the vector format object Pd11A is printed based on the print data.

[0059] In this embodiment, the printing unit 84 performs printing by ejecting ink in dots of multiple sizes (here, first dots Dt11 to third dots Dt13) based on the print data converted by the first conversion unit 81, second conversion unit 82, and intermediate conversion unit 83. Here, the printing unit 84 performs printing of the first area AR11, second area AR12, and intermediate area AR13 collectively (i.e., at one time). Note that printing of each area is specifically performed as follows.

[0060] For example, the printing unit 84 uses first dot allocation ratio information R11 (see FIG. 6) to print a first area AR11 of a vector-format object Pd11A based on the print data. The printing unit 84 ejects ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the first allocation ratio Rt1 according to the gradient, to print the first area AR11 of the line Pd21A in the vector-format object Pd11A and the first area AR11 of the character Pd22A.

[0061] The printing unit 84 uses the second dot allocation ratio information R12 (see FIG. 7) to print the second area AR12 of the vector-format object Pd11A based on the print data. The printing unit 84 ejects ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the second allocation ratio Rt2 according to the gradient, to print the second area AR12 of the line Pd21A in the vector-format object Pd11A and the second area AR12 of the character Pd22A.

[0062] The printing unit 84 prints the intermediate area AR13 of the vector-format object Pd11A based on the print data using the intermediate dot allocation rate information R13 (see FIG. 11). The printing unit 84 ejects ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the intermediate allocation rate Rt3 according to the gradient, to print the intermediate area AR13 of the line Pd21A in the vector-format object Pd11A and the intermediate area AR13 of the character Pd22A.

[0063] As described above, in this embodiment, the object Pd11A is printed in vector format using the first dot allocation rate information R11, the second dot allocation rate information R12, and the intermediate dot allocation rate information R13 created based on the first dot allocation rate information R11 and the second dot allocation rate information R12.

[0064] Fig. 12 is a diagram showing a raster-format object Pd12A in input data Pd1A. Fig. 13 is a flowchart showing print control for the raster-format object Pd12A in the input data Pd1A. Next, the procedure for printing the raster-format object Pd12A in the input data Pd1A shown in Fig. 12 on the medium 5 will be described with reference to the flowchart in Fig. 13.

[0065] 13, in step S201, the first acquisition unit 71 of FIG. 3 acquires first dot allocation rate information R11 (see FIG. 6), and in step S203, the second acquisition unit 72 of FIG. 3 acquires second dot allocation rate information R12 (see FIG. 7). In step S205, the intermediate allocation rate creation unit 73 of FIG. 3 creates intermediate dot allocation rate information R13 (see FIG. 11) based on the first dot allocation rate information R11 and the second dot allocation rate information R12. In step S207, the acquisition unit 74 of FIG. 3 acquires input data Pd1A that includes at least a raster-format object Pd12A as shown in FIG. 12. Here, steps S201, S203, S205, and S207 in FIG. 13 are the same as steps S101, S103, S105, and S107 in FIG. 10, respectively, and therefore will not be described here.

[0066] Next, in step S209 of FIG. 13, the image correction processing unit 91 of FIG. 3 performs image correction processing on the input data Pd1A (see FIG. 12) acquired by the acquisition unit 74 to correct color values. The image correction processing is a preprocessing for reducing the load of the edge detection processing described below, and by performing the image correction processing, edges become easier to detect. Here, the image correction processing includes grayscale processing. This grayscale processing allows colors in the input data Pd1A to be expressed in grayscale. The input data Pd1A that has undergone grayscale processing is data that does not contain information other than luminosity. For example, the input data Pd1A in raster format is expressed in gray shades ranging from white, which is the most luminous, to black, which is the least luminous. Note that as part of the image correction processing, a spatial filter (e.g., an edge enhancement filter, a noise reduction filter, a color correction filter, etc.) may be applied to the input data Pd1A.

[0067] Next, in step S211 of FIG. 13, the edge detection unit 92 of FIG. 3 detects edges of a raster-format object Pd12A of the input data Pd1A. In this embodiment, the edge detection unit 92 detects edges of the raster-format object Pd12A of the input data Pd1A that has been subjected to image correction processing. FIG. 14 is a diagram showing the raster-format object Pd12A after edge detection. Here, the specific control for detecting edges is not particularly limited. In this embodiment, the edge detection unit 92 detects edges of the object Pd12A by extracting only the contour line of the raster-format object Pd12A, as shown in FIG. 14.

[0068] For example, the edge of a raster-format object Pd12A can be considered the contour of the raster-format object Pd12A. Here, by detecting the edge, information other than the contour of the raster-format object Pd12A, such as filled-in areas, is deleted. Note that the input data Pd1A may include a vector-format object Pd11A (see FIGS. 8 and 9) in addition to the raster-format object Pd12A. In this case, the image correction process of step S209 in FIG. 13 may be performed on the vector-format object Pd11A, and edge detection of step S211 may be performed. Furthermore, if the input data Pd1A includes both the raster-format object Pd12A and the vector-format object Pd11A, image correction and edge detection may be performed after RIP (rasterization) processing of both objects Pd11A and Pd12A.

[0069] Next, in step S213 of FIG. 13, the distance calculation unit 93 of FIG. 3 calculates the edge-to-edge distance D1 of the raster-format object Pd12A as shown in FIG. 14 based on the edges of the raster-format object Pd12A detected by the edge detection unit 92. Here, the edge-to-edge distance D1 refers to the width (in other words, thickness) of the filled portion of the raster-format object Pd12A. The edge-to-edge distance D1 refers to, for example, the distance between the contours of the raster-format object Pd12A in a direction perpendicular to the contours. Therefore, the direction of the edge-to-edge distance D1 is not particularly limited and is determined depending on the shape, size, etc. of the raster-format object Pd12A. However, to shorten the time required for control, the direction of the edge-to-edge distance D1 may be predetermined to a predetermined direction such as the main scanning direction Y or the sub-scanning direction X. The edge-to-edge distance D1 calculated by the distance calculation unit 93 is stored in the storage unit 61.

[0070] If the input data Pd1A includes an object Pd11A in vector format, the edge-to-edge distance D1 is not calculated for the object Pd11A in vector format. However, the distance calculation unit 93 can also calculate the edge-to-edge distance D1 for the object Pd11A in vector format.

[0071] Next, in step S215 of FIG. 13, the division unit 75 of FIG. 3 divides the raster-formatted object Pd12A of the input data Pd1A into a first region AR21, a second region AR22, and an intermediate region AR23, as shown in FIG. 14. Here, the raster-formatted object Pd12A is divided according to the edge-to-edge distance D1 of the raster-formatted object Pd12A. In this embodiment, the region of the object Pd12A with the large edge-to-edge distance D1 is defined as the first region AR21, and the region of the object Pd12A with the small edge-to-edge distance D1 is defined as the second region AR22. The region of the object Pd12A between the object Pd12A with the large edge-to-edge distance D1 and the object Pd12A with the small edge-to-edge distance D1 is defined as the intermediate region AR23. Here, the intermediate region AR23 is the entire region of the raster-formatted object Pd12A excluding the first region AR21 and the second region AR22.

[0072] In this embodiment, the edge-to-edge distance D1 of the raster-formatted object Pd12A at the boundary between the first region AR21 and the intermediate region AR23 is the first distance. That is, the dividing unit 75 defines the region of the raster-formatted object Pd12A where the edge-to-edge distance D1 of the raster-formatted object Pd12A is greater than the first distance as the first region AR21. In FIG. 14, the boundary line D11 is the line indicating the boundary between the first region AR21 and the intermediate region AR23. Here, the edge-to-edge distance D1 of the raster-formatted object Pd12A at the boundary between the intermediate region AR23 and the second region AR22 is the second distance. That is, the dividing unit 75 defines the region of the raster-formatted object Pd12A where the edge-to-edge distance D1 of the raster-formatted object Pd12A is smaller than the second distance as the second region AR22. In FIG. 14, the boundary line D12 is the line indicating the boundary between the intermediate region AR23 and the second region AR22. The dividing unit 75 defines, as an intermediate area AR23, an area of ​​the object Pd12A in raster format where the distance D1 between edges of the object Pd12A is equal to or less than the first distance and equal to or greater than the second distance.

[0073] Next, in step S217 of Fig. 13, the input data Pd1A is subjected to RIP processing and converted into print data. This step S217 is the same as step S113 of Fig. 10. Here, the first conversion unit 81 converts the first region AR21 of the raster-formatted object Pd12A into print data for printing based on the first allocation rate Rt1 (see Fig. 6). The second conversion unit 82 converts the second region AR22 of the raster-formatted object Pd12A into print data based on the second allocation rate Rt2 (see Fig. 7). The intermediate conversion unit 83 converts the intermediate region AR23 of the raster-formatted object Pd12A into print data based on the intermediate allocation rate Rt3 (see Fig. 11).

[0074] Next, in step S219 of FIG. 13, the printing unit 84 of FIG. 3 ejects ink to print dots of multiple sizes (here, first dot Dt11 to third dot Dt13) onto the medium 5 based on the print data converted by the first conversion unit 81, second conversion unit 82, and intermediate conversion unit 83. Here, the printing unit 84 prints the first area AR21, second area AR22, and intermediate area AR23 all at once (i.e., all at once). Note that printing of each area is specifically performed as follows.

[0075] In this embodiment, the printing unit 84 uses first dot allocation ratio information R11 (see FIG. 6) to print the first area AR21 of the raster-format object Pd12A. The printing unit 84 prints the first area AR21 of the raster-format object Pd12A by ejecting ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the first allocation ratio Rt1 according to the gradient.

[0076] The printing unit 84 uses the second dot allocation ratio information R12 (see FIG. 7) to print the second area AR22 of the raster-format object Pd12A. The printing unit 84 prints the second area AR22 of the raster-format object Pd12A by ejecting ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the second allocation ratio Rt2 according to the gradient.

[0077] The printing unit 84 uses the intermediate dot allocation rate information R13 (see FIG. 11) to print the intermediate area AR23 of the raster-format object Pd12A. The printing unit 84 prints the intermediate area AR23 of the raster-format object Pd12A by ejecting ink in dots of multiple sizes (here, first dot Dt11 to third dot Dt13) at the intermediate allocation rate Rt3 according to the gradient.

[0078] As described above, in this embodiment, the raster format object Pd12A of the input data Pd1A is printed using the first dot allocation rate information R11, the second dot allocation rate information R12, and the intermediate dot allocation rate information R13 created based on the first dot allocation rate information R11 and the second dot allocation rate information R12.

[0079] If the input data Pd1A includes both a vector-format object Pd11A (see FIGS. 8 and 9) and a raster-format object Pd12A (see FIG. 12), the flowchart of FIG. 10 and the flowchart of FIG. 13 are executed simultaneously. Here, steps S101, S103, S105, and S107 of FIG. 10 are executed simultaneously with steps S201, S203, S205, and S207 of FIG. 13, respectively. Thereafter, steps S209, S211, and S213 of FIG. 13 are executed in order. Then, step S109 in Figure 10 and step S215 in Figure 13 are executed simultaneously, step S111 in Figure 10 and step S217 in Figure 13 are executed simultaneously, and step S113 in Figure 10 and step S219 in Figure 13 are executed simultaneously, and a vector-format object Pd11A and a raster-format object Pd12A are printed simultaneously on the medium 5 based on the print data converted from the input data Pd1A.

[0080] As described above, in this embodiment, as shown in FIG. 1, printer 10 includes support base 13 that supports medium 5, ink head 20 (see FIG. 2) that can eject ink in dots Dt1 of multiple sizes (see FIG. 4), movement mechanism 30 that relatively moves medium 5 supported by support base 13 and ink head 20, and control device 60. As shown in FIG. 3, control device 60 includes first acquisition unit 71, second acquisition unit 72, intermediate allocation rate creation unit 73, acquisition unit 74, division unit 75, first conversion unit 81, second conversion unit 82, intermediate conversion unit 83, and printing unit 84. First acquisition unit 71 acquires first dot allocation rate information R11 (see FIG. 6) in which the allocation rate of ink to dots Dt1 of multiple sizes is indicated by a first allocation rate Rt1 according to the gradient. The second acquisition unit 72 acquires second dot allocation rate information R12 (see FIG. 7) that indicates the allocation rate of ink to dots Dt1 of multiple sizes at a second allocation rate Rt2 that sets a higher allocation rate for ink to smaller dots Dt1 than the first allocation rate Rt1. The intermediate allocation rate creation unit 73 creates intermediate dot allocation rate information R13 (see FIG. 11) that indicates the allocation rate of ink to dots Dt1 of multiple sizes at an intermediate allocation rate Rt3 that is between the first allocation rate Rt1 and the second allocation rate Rt2, based on the first dot allocation rate information R11 and the second dot allocation rate information R12. The acquisition unit 74 acquires printable input data Pd1A (see FIGS. 8 and 9) that includes at least an object Pd11A in vector format. As shown in Fig. 8, the dividing unit 75 divides the area of ​​the vector-format object Pd11A in the input data Pd1A into a first area AR11 where the thickness of the vector-format object Pd11A is greater than a first thickness, a second area AR12 where the thickness of the vector-format object Pd11A is smaller than a second thickness that is smaller than the first thickness, and an intermediate area AR13 where the thickness of the vector-format object Pd11A is equal to or smaller than the first thickness and equal to or larger than the second thickness. The first conversion unit 81 converts the first area AR11 of the vector-format object Pd11A into print data for printing based on a first allocation ratio Rt1 (see Fig. 6). The second conversion unit 82 converts the second area AR12 of the vector-format object Pd11A into print data based on a second allocation ratio Rt2 (see Fig. 7).The intermediate conversion unit 83 converts the intermediate area AR13 of the object Pd11A in vector format into print data based on the intermediate allocation rate Rt3 (see FIG. 11). The printing unit 84 performs printing by ejecting ink in dots Dt1 of multiple sizes based on the print data converted by the first conversion unit, second conversion unit 82, and intermediate conversion unit 83.

[0081] According to this embodiment, intermediate dot allocation rate information R13 used for an intermediate area AR13 between the first area AR11 and the second area AR12 is created based on first dot allocation rate information R11 used for a first area AR11 of the vector-format object Pd11A that is larger than the first thickness, and second dot allocation rate information R12 used for a second area AR12 that is smaller than the second thickness. Therefore, when printing is performed based on print data obtained by converting the intermediate area AR13 of the vector-format object Pd11A, multiple ink dots Dt1 are ejected at an intermediate allocation rate Rt3 that is between the first allocation rate Rt1 and the second allocation rate Rt2. This makes it possible to reduce printing differences at the boundaries between the first area AR11 and the intermediate area AR13 and between the intermediate area AR13 and the second area AR12 compared to conventional methods. Therefore, by printing based on print data converted from input data Pd1A using intermediate dot allocation rate information R13 in addition to first dot allocation rate information R11 and second dot allocation rate information R12, it is possible to suppress deterioration in print quality.

[0082] In this embodiment, as shown in FIG. 8, the object Pd11A in vector format includes a line Pd21A. The dividing unit 75 defines a first region AR11 as a region of the line Pd21A where the width of the line Pd21A is greater than a first width, a second region AR12 as a region of the line Pd21A where the width of the line Pd21A is smaller than a second width that is smaller than the first width, and an intermediate region AR13 as a region of the line Pd21A where the width is equal to or smaller than the first width and equal to or larger than the second width. In this manner, when the object Pd11A in vector format is the line Pd21A, the region of the line Pd21A can be divided into the first region AR11, the second region AR12, and the intermediate region AR13 according to the width of the line Pd21A. Therefore, when printing the intermediate region AR13 of the line Pd21A, multiple ink dots Dt1 are ejected at an intermediate allocation rate Rt3 that is between the first allocation rate Rt1 and the second allocation rate Rt2. Therefore, compared to the conventional method, it is possible to reduce the printing difference on the line Pd21A at the boundary between the first area AR11 and the intermediate area AR13, and the printing difference on the line Pd21A at the boundary between the intermediate area AR13 and the second area AR12. Therefore, it is possible to suppress deterioration in printing quality on the line Pd21A.

[0083] In this embodiment, as shown in FIG. 9, the vector object Pd11A includes the character Pd22A. The dividing unit 75 defines the area of ​​the character Pd22A where the size of the character Pd22A is larger than a first size as a first area AR11, the area where the size of the character Pd22A is smaller than a second size (which is smaller than the first size) as a second area AR12, and the area where the size of the character Pd22A is equal to or smaller than the first size and equal to or larger than the second size as an intermediate area AR13. In this way, when the vector object Pd11A is the character Pd22A, the area of ​​the character Pd22A can be divided into the first area AR11, the second area AR12, and the intermediate area AR13 according to the size of the character Pd22A. Therefore, when printing the intermediate area AR13 of the character Pd22A, multiple ink dots Dt1 are ejected at an intermediate allocation rate Rt3 between the first allocation rate Rt1 and the second allocation rate Rt2. Therefore, compared to the conventional method, it is possible to reduce the printing difference in the character Pd22A at the boundary between the first area AR11 and the intermediate area AR13, and the printing difference in the character Pd22A at the boundary between the intermediate area AR13 and the second area AR12. Therefore, it is possible to suppress a decrease in the printing quality of the character Pd22A.

[0084] In this embodiment, as shown in FIG. 3, the control device 60 of the printer 10 includes an acquisition unit 74, an edge detection unit 92, a distance calculation unit 93, a division unit 75, a first conversion unit 81, a second conversion unit 82, and an intermediate conversion unit 83. As shown in FIG. 12, the acquisition unit 74 acquires printable input data Pd1A including at least a raster-format object (e.g., an image) Pd12A. As shown in FIG. 14, the edge detection unit 92 detects the edges of the raster-format object Pd12A in the input data Pd1A. The distance calculation unit 93 calculates the distance D1 between edges of the object Pd12A based on the edges of the raster-format object Pd12A detected by the edge detection unit 92. The dividing unit 75 divides the area of ​​the raster-format object Pd12A in the input data Pd1A into a first area AR21 where the edge-to-edge distance D1 is greater than a first distance, a second area AR22 where the edge-to-edge distance D1 is smaller than a second distance that is smaller than the first distance, and an intermediate area AR23 where the edge-to-edge distance D1 is equal to or less than the first distance and equal to or greater than the second distance. The first conversion unit 81 converts the first area AR21 of the raster-format object Pd12A into print data for printing based on a first allocation rate Rt1 (see FIG. 6). The second conversion unit 82 converts the second area AR22 of the raster-format object Pd12A into print data based on a second allocation rate Rt2 (see FIG. 7). The intermediate conversion unit 83 converts the intermediate area AR23 of the raster-format object Pd12A into print data based on an intermediate allocation rate Rt3 (see FIG. 11). The printing unit 84 performs printing by ejecting ink in the form of dots Dt1 of a plurality of sizes based on the print data converted by the first conversion unit 81, the second conversion unit 82, and the intermediate conversion unit 83.

[0085] Here, the lines and other elements constituting the raster object Pd12A included in the input data Pd1A do not include information about thickness (e.g., width). However, in this embodiment, edges are detected for the raster object Pd12A in the input data Pd1A and the edge-to-edge distance D1 is calculated, so that the thickness of the lines and other elements constituting the raster object Pd12A can be calculated as the edge-to-edge distance D1. Therefore, the area in the raster object Pd12A where the edge-to-edge distance D1 is less than the first distance and greater than the second distance is defined as the intermediate area AR23. When printing is performed based on print data obtained by converting the intermediate area AR23 of the raster object Pd12A, multiple ink dots Dt1 are ejected at an intermediate allocation rate Rt3 that is between the first allocation rate Rt1 and the second allocation rate Rt2. Therefore, compared to the prior art, it is possible to reduce the printing difference of object Pd12A at the boundary between first area AR21 and intermediate area AR23, and the printing difference of object Pd12A at the boundary between intermediate area AR23 and second area AR22. As a result, by printing based on print data obtained by converting input data Pd1A using intermediate dot allocation rate information R13 in addition to first dot allocation rate information R11 and second dot allocation rate information R12, it is possible to suppress degradation in print quality.

[0086] In this embodiment, the control device 60 includes an image correction processing unit 91 (see FIG. 3) that executes image correction processing to correct color values ​​of input data Pd1A acquired by the acquisition unit 74. The edge detection unit 92 detects edges of raster-format objects Pd12A in the image-corrected input data Pd1A. For example, grayscale processing, which is an example of image correction processing, can be used to represent colors in grayscale. Therefore, the edges of the raster-format objects Pd12A are detected without color information, allowing for more appropriate edge detection of the objects Pd12A.

[0087] In this embodiment, as shown in Fig. 4, the ink dots Dt1 ejected from the ink head 20 include a first dot Dt11 having a first diameter A11, a second dot Dt12 having a second diameter A12 smaller than the first diameter A11, and a third dot Dt13 having a third diameter A13 smaller than the second diameter A12. As shown in Figs. 6 and 7, in the second dot allocation ratio information R12, the second allocation ratio Rt2 sets the ink allocation ratio of the third dots Dt13 higher than the first allocation ratio Rt1. As a result, when printing the second region AR12 of a vector-format object Pd11A with a small thickness or the second region AR22 of a raster-format object Pd12A with a small edge-to-edge distance D1, the third dots Dt13 with a small diameter are printed with a larger amount of ink. Therefore, quality can be ensured even for a vector-format object Pd11A with a small thickness and a raster-format object Pd12A with a small edge-to-edge distance D1.

[0088] In this embodiment, in the second dot allocation rate information R12, the second allocation rate Rt2 sets a higher allocation rate for the ink of the second dots Dt12 than the first allocation rate Rt1. As a result, when printing the second area AR12 of a vector-format object Pd11A with a small thickness or the second area AR22 of a raster-format object Pd12A with a small edge-to-edge distance D1, the second dots Dt12 with a smaller diameter than the first dots Dt11 are printed with a larger amount of ink. Therefore, quality can be ensured even for a vector-format object Pd11A with a small thickness and a raster-format object Pd12A with a small edge-to-edge distance D1.

[0089] In this embodiment, in the second dot allocation rate information R12, the second allocation rate Rt2 sets a lower allocation rate for the ink of the first dots Dt11 than the first allocation rate Rt1. As a result, when printing the second area AR12 of a vector-format object Pd11A with a small thickness or the second area AR22 of a raster-format object Pd12A with a small edge-to-edge distance D1, the amount of ink for the large-diameter first dots Dt11 is reduced. Therefore, quality can be ensured even for a vector-format object Pd11A with a small thickness and a raster-format object Pd12A with a small edge-to-edge distance D1.

[0090] In this embodiment, the intermediate allocation rate creation unit 73 calculates the intermediate allocation rate Rt3 by linearly interpolating the first allocation rate Rt1 and the second allocation rate Rt2, and creates the intermediate dot allocation rate information R13. In this way, by using linear interpolation technology, the intermediate dot allocation rate information R13 can be easily created from the first dot allocation rate information R11 and the second dot allocation rate information R12.

[0091] In this embodiment, the first dot allocation rate information R11 and the second dot allocation rate information R12 are expressed as a table showing the ratio of each of the multiple dots Dt1 to the gradient of the input data Pd1 A. This makes it easy to manage the first dot allocation rate information R11 and the second dot allocation rate information R12.

[0092] In this embodiment, printing was performed using the same first dot allocation rate information R11, second dot allocation rate information R12, and intermediate dot allocation rate information R13 for the lines Pd21A and characters Pd22A of the vector-format object Pd11A and the raster-format object Pd12A. However, first dot allocation rate information R11 with different allocation rates may be used for the lines Pd21A and characters Pd22A of the vector-format object Pd11A and the raster-format object Pd12A, and second dot allocation rate information R12 with different allocation rates may be used. In this case, intermediate dot allocation rate information R13 with different allocation rates may be used for the lines Pd21A and characters Pd22A of the vector-format object Pd11A and the raster-format object Pd12A. That is, dedicated first dot allocation rate information R11, second dot allocation rate information R12, and intermediate dot allocation rate information R13 may be set for the lines Pd21A and characters Pd22A of the vector-format object Pd11A, and the raster-format object Pd12A, respectively.

[0093] In this embodiment, the edges of the raster-format object Pd12A are detected after the image correction process is performed on the raster-format object Pd12A of the input data Pd1A. However, the image correction process may be omitted. [Explanation of symbols]

[0094] 5 Medium 10 Printer (inkjet printer) 13 Support stand 20 ink head 30 Moving mechanism 60 Control device 71 First acquisition part 72 Second acquisition part 73 Intermediate Allocation Rate Creation Department 74 Acquisition Department 75 Split part 81 First conversion unit 82 Second conversion unit 83 Intermediate conversion section 84 Printing Department 91 Image correction processing section 92 Edge detection unit 93 Distance calculation unit AR11, AR21 1st area AR12, AR22 2nd area AR13, AR23 intermediate area Pd1, Pd1A input data Pd11, Pd11A vector format objects Pd12, Pd12A raster format objects Pd21, Pd21A wire Pd22, Pd22A characters

Claims

1. a support base for supporting the medium; an ink head capable of ejecting ink in dots of a plurality of sizes; a moving mechanism that moves the medium supported by the support table and the ink head relatively; a control device; Equipped with The control device a first acquisition unit that acquires first dot allocation ratio information in which ink allocation ratios of dots of a plurality of sizes are indicated by first allocation ratios according to gradients; a second acquisition unit that acquires second dot allocation ratio information indicating the allocation ratio of ink to dots of a plurality of sizes at a second allocation ratio that sets a higher allocation ratio for ink to small dots than the first allocation ratio; an intermediate allocation rate creation unit that creates intermediate dot allocation rate information indicating the allocation rates of ink for dots of a plurality of sizes at an intermediate allocation rate between the first allocation rate and the second allocation rate based on the first dot allocation rate information and the second dot allocation rate information; an acquisition unit for acquiring printable input data including at least a vector format object; a dividing unit that divides a region of the vector-format object of the input data into a first region where the thickness of the vector-format object is greater than a first thickness, a second region where the thickness of the vector-format object is smaller than a second thickness that is smaller than the first thickness, and an intermediate region where the thickness of the vector-format object is equal to or smaller than the first thickness and equal to or larger than the second thickness; a first conversion unit that converts the first area of ​​the object in vector format into print data for printing based on the first allocation ratio; a second conversion unit that converts the second area of ​​the object in vector format into the print data based on the second allocation ratio; an intermediate conversion unit that converts the intermediate area of ​​the object in vector format into the print data based on the intermediate allocation rate; a printing unit that performs printing by ejecting ink in dots of a plurality of sizes based on the print data converted by the first conversion unit, the second conversion unit, and the intermediate conversion unit; An inkjet printer equipped with

2. the vector-based object includes a line; 2. The inkjet printer according to claim 1, wherein the dividing unit defines, within the line region, a region where the line width is greater than a first width as the first region, a region where the line width is smaller than a second width that is smaller than the first width as the second region, and a region where the line width is equal to or smaller than the first width and equal to or larger than the second width as the intermediate region.

3. the vector-based object includes text; 3. The inkjet printer according to claim 1, wherein the dividing unit defines, among the character regions, a region in which the character size is larger than a first size as the first region, a region in which the character size is smaller than a second size smaller than the first size as the second region, and a region in which the character size is equal to or smaller than the first size and equal to or larger than the second size as the intermediate region.

4. a support base for supporting the medium; an ink head capable of ejecting ink in dots of a plurality of sizes; a moving mechanism that moves the medium supported by the support table and the ink head relatively; a control device; Equipped with The control device a first acquisition unit that acquires first dot allocation ratio information in which ink allocation ratios of dots of a plurality of sizes are indicated by first allocation ratios according to gradients; a second acquisition unit that acquires second dot allocation ratio information indicating the allocation ratio of ink to dots of a plurality of sizes at a second allocation ratio that sets a higher allocation ratio for ink to small dots than the first allocation ratio; an intermediate allocation rate creation unit that creates intermediate dot allocation rate information indicating the allocation rates of ink for dots of a plurality of sizes at an intermediate allocation rate between the first allocation rate and the second allocation rate based on the first dot allocation rate information and the second dot allocation rate information; an acquisition unit that acquires printable input data including at least an object; an edge detection unit that detects edges of the object in the input data; a distance calculation unit that calculates a distance between edges of the object based on the edges of the object detected by the edge detection unit; a dividing unit that divides a region of the object in the input data into a first region in which the edge-to-edge distance is greater than a first distance, a second region in which the edge-to-edge distance is smaller than a second distance that is smaller than the first distance, and an intermediate region in which the edge-to-edge distance is equal to or less than the first distance and equal to or greater than the second distance; a first conversion unit that converts the first area of ​​the object into print data for printing based on the first allocation ratio; a second conversion unit that converts the second area of ​​the object into the print data based on the second allocation ratio; an intermediate conversion unit that converts the intermediate area of ​​the object into the print data based on the intermediate allocation ratio; a printing unit that performs printing by ejecting ink in dots of a plurality of sizes based on the print data converted by the first conversion unit, the second conversion unit, and the intermediate conversion unit; An inkjet printer equipped with

5. the control device includes an image correction processing unit that executes image correction processing to correct color values ​​of the input data acquired by the acquisition unit, 5. The inkjet printer according to claim 4, wherein the edge detection section detects edges of the object in the input data that has been subjected to the image correction process.

6. 6. An inkjet printer according to claim 4, wherein the objects include at least raster objects.

7. The ink dots ejected from the ink head are a first dot having a first diameter; a second dot having a second diameter smaller than the first diameter; a third dot having a third diameter smaller than the second diameter; 7. An ink jet printer according to claim 1, comprising:

8. 8. The inkjet printer according to claim 7, wherein in the second dot allocation rate information, the second allocation rate sets an ink allocation rate for the third dot higher than the first allocation rate.

9. 9. The inkjet printer according to claim 7, wherein in the second dot allocation rate information, the second allocation rate sets an allocation rate of ink for the second dots higher than the first allocation rate.

10. 10. The inkjet printer according to claim 7, wherein in the second dot allocation rate information, the second allocation rate has an ink allocation rate for the first dots that is lower than the first allocation rate.

11. An inkjet printer described in any one of claims 1 to 10, wherein the intermediate allocation rate creation unit calculates the intermediate allocation rate by linearly interpolating the first allocation rate and the second allocation rate, and creates the intermediate dot allocation rate information.

12. 12. An inkjet printer according to claim 1, wherein the first dot allocation rate information and the second dot allocation rate information are expressed as a table showing the respective ratios of a plurality of dots to the gradation of the input data.

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