JP2024076456A - Printing device, printing system, and printing method - Google Patents

Abstract

[Problem] To provide a printing device, printing system, and printing method capable of printing without degrading the image quality of an image based on print data, even when correction is performed to prevent a decrease in code reading accuracy. [Solution] The printing device executes the following steps: determining whether or not to perform correction to delete selected dot data from first print data based on a dot pattern in a predetermined range including the selected dot data and a predetermined comparison pattern; designating either a first range, which is the range of dots forming the first image, or a second range, which is the range of dots forming the second image; performing correction in the first range when the first range is designated, and maintaining the second range without performing correction when the second range is designated; and printing based on second print data obtained by performing correction or maintenance on the first print data. [Selected Figure] Figure 7

Description

The present invention relates to a printing device, a printing system, and a printing method.

Conventionally, there is known a printing system that aims to print tables and ruled lines other than barcodes well without reducing the accuracy of reading barcodes. In this case, if the print data is barcode data, the printer driver prints the print data without correcting the print data to thicken the outlines, and if the print data is not barcode data, the printer driver prints the print data after correcting the print data to thicken the outlines.

However, when droplets are ejected onto a print medium to print a barcode, the droplets may bleed onto the print medium. This increases the line width of the barcode, decreasing the accuracy of reading the barcode. A printing device is therefore known that performs correction using multiple comparison patterns, which are comparison dot patterns for dots located at a specific edge of the image to be formed (peripheral dots around the selected dot that is the subject of attention) (see Patent Document 1). In this printing device, when the peripheral dots match dots in each comparison pattern, a correction is performed to make the selected dot that corresponds to the peripheral dot blank data.

JP 2022-084291 A

Incidentally, print data may contain images that do not contain barcodes in addition to images that contain barcodes. An example of an image that does not contain a barcode is a corporate logo. In this corporate logo, for example, the company name is printed in white and the background image of the company name is colored. However, with conventional technology that performs the above correction on an image that contains a barcode, the background image is undesirably corrected. As a result, the background image turns white, and the company name in the corporate logo visually disappears, resulting in a problem of reduced image quality.

The present invention aims to provide a printing device, printing system, and printing method that can print images based on print data without degrading the image quality, even when corrections are made to avoid degrading the accuracy of reading the code.

The printing device of the present invention comprises an ejection head that ejects droplets onto a print medium, and a controller, and the controller includes a process of acquiring first print data for forming a first image including a code having information and a second image not including the code on the print medium by dots formed by landing the droplets on the print medium, and a process of selecting, from the acquired first print data, at least one of first dot data corresponding to the dots forming the first image and second dot data corresponding to the dots forming the second image, and calculating the first print data based on a predetermined range of dot patterns including the selected dot data, which is the selected dot data, and a predetermined comparison pattern. The process executes a process of determining whether or not to perform a correction to delete the selected dot data from the data, a process of designating one of a first range, which is a range of dots forming the first image, and a second range, which is a range of dots forming the second image, a process of performing the correction in the first range when the first range is designated, and a process of maintaining the second range without performing the correction when the second range is designated, and a process of ejecting the droplets from the ejection head onto the print medium based on second print data obtained by performing the correction or the maintenance on the first print data, thereby forming the first image and the second image on the print medium.

According to the present invention, in the above-mentioned designation process, either a first range for performing correction or a second range for not performing correction is designated. Then, when the first range is designated, the above-mentioned correction is performed in the first range, and when the second range is designated, the above-mentioned correction is not performed in the second range and is maintained. This makes it possible to limit the range for which correction is performed. In other words, by designating the range for which correction is desired to be performed as the first range, it is possible to indirectly designate the range for which correction is desired to be avoided, and by designating the second range, it is possible to directly designate the range for which correction is desired to be avoided. This makes it possible to perform correction so as not to reduce the accuracy of reading the code, excluding the image for which correction is desired to be avoided. Therefore, it is possible to print an image on a printing medium without reducing the image quality based on print data including the image for which correction is desired to be avoided.

The present invention provides a printing device, printing system, and printing method that can print images based on print data without degrading the image quality, even when corrections are made to avoid degrading the accuracy of reading the code.

1 is a plan view showing a printing apparatus according to an embodiment of the present invention. 2 is a bottom view of the ejection head provided in the printing device of FIG. 1. FIG. 2 is a block diagram showing the configuration of a control system in the printing apparatus of FIG. 1 . FIG. 2 shows an example of a first image including a code having information and a second image not including the code. FIG. 5A shows the image before processing, FIG. 5B shows a comparison between a dot pattern in a specified range including selected dot data and a comparison pattern, and FIG. 5C shows the image after correction has been performed. FIG. 6A is a diagram showing an example of an image formed using halftone, and FIG. 6B is a diagram showing an image after correction has been applied to the image in FIG. 6A. FIG. 7A is a diagram showing a table storing conditions for performing correction, and FIG. 7B is a diagram showing a table prescribing a method for designating an area corresponding to the conditions in FIG. 7A. 4 is a flowchart showing a printing process. FIG. 9A is a diagram showing an intermediately disposed image located between two first images, and FIG. 9B is a diagram for explaining overlay, which is an area designation when correcting the image of FIG. 9A. 1 is a block diagram showing a configuration of a printing system according to an embodiment of the present invention.

The printing device according to an embodiment of the present invention will be described below with reference to the drawings. The printing device described below is merely one embodiment of the present invention. Therefore, the present invention is not limited to the following embodiment, and additions, deletions, and modifications are possible without departing from the spirit of the present invention.

1 is a plan view showing a printing device 10 according to an embodiment of the present invention. FIG. 2 is a bottom view of the ejection head 30 provided in the printing device 10 of FIG. 1. FIG. 3 is a block diagram showing the configuration of a control system in the printing device 10 of FIG. 1. In FIG. 1 and FIG. 2, directions perpendicular to each other are defined as a first direction Ds and a second direction Df. In this embodiment, for example, the second direction Df is the transport direction of the print medium W described later, and the first direction Ds is the extension direction of the line head type ejection head 30 described later. In the following description, Ds is called the extension direction, Df is called the transport direction, one side of the extension direction Ds is the left side, the other side of the extension direction Ds is the right side, one side of the transport direction Df is the front, and the other side of the transport direction Df is the rear. However, the above directions are merely examples and are not limited.

As shown in FIG. 1, the printing device 10 is, for example, an inkjet printer that ejects ink droplets onto a print medium W, which is a print sheet. The printing device 10 includes a housing 11, a platen 12, a transport device 20, one or more (for example, four) ejection heads 30, a tank 13, and a controller 40. The ejection head 30 is, for example, a line head.

The housing 11 houses the platen 12, the transport device 20, the ejection head 30, the tank 13, and the controller 40. The platen 12 has a flat upper surface on which the print medium W is placed.

The transport device 20 has a pair of transport rollers 21 and a transport motor 22 (Figure 3). The pair of transport rollers 21 are arranged in the transport direction Df to sandwich the ejection head 30 between them, and are aligned parallel to each other with their central axes extending in the extension direction Ds. The transport motor 22 is connected to the transport rollers 21 and rotates the transport rollers 21 to transport the print medium W forward.

The ejection heads 30 are fixed to the housing 11 and are, for example, rectangular in shape, with dimensions in the extension direction Ds longer than the dimensions of the print medium W. The lower surfaces of the ejection heads 30 are disposed facing the upper surface of the platen 12. The four ejection heads 30 are aligned in a line in the transport direction Df.

For example, the tanks 13 are provided in the same number as the ejection heads 30, each of which stores a different type of ink, and is connected to the ejection heads 30 by a tube 14. For example, four tanks 13 store cyan, magenta, yellow, and black ink, respectively, and supply ink to the corresponding ejection heads 30 via the tube 14.

As shown in FIG. 2, the ejection head 30 has a holding base 31 and a number of chips 32. The holding base 31 is, for example, rectangular parallelepiped shaped, and holds the chips 32 so that the undersides of the chips 32 are exposed on its underside. Note that only one ejection head 30 is shown in FIG. 2.

The chip 32 has a number of nozzles 33 and driving elements 34 (Figure 3) corresponding to the nozzles 33. The nozzles 33 are connected to the tank 13 via a liquid flow path and a tube 14. The nozzles 33 are arranged, for example, in a row at a predetermined interval from each other in the extension direction Ds to form a nozzle row. In each chip 32, the nozzle rows are arranged in the transport direction Df so that the nozzles 33 are arranged at equal intervals in the extension direction Ds.

The multiple chips 32 are arranged in the extension direction Ds on the holding table 31, and adjacent chips 32 are arranged with a shift in the transport direction Df. Therefore, the multiple chips 32 are arranged in the extension direction Ds so that they are staggered one by one in the transport direction Df. The multiple chips 32 are arranged so that the multiple nozzles 33 are arranged at equal intervals in the extension direction Ds and the total length in the extension direction Ds is longer than the printing medium W.

As shown in FIG. 3, the controller 40 has a calculation unit 41, a memory unit 42, and an interface 43. The controller 40 may be a single controller, or may be composed of multiple controllers.

The interface 43 is connected to an external device B such as a computer, a network, and a recording medium, and receives various data such as print data from the external device B. The calculation unit 41 of the controller 40 acquires print data from the external device B via the interface 43. The print data may be input by a user using an input device 15 such as a keyboard and a mouse provided in the printing device 10. Such print data is data for forming a first image including a code having predetermined information and a second image not including a code on the printing medium W by dots formed by landing ink droplets on the printing medium W, and includes image data such as raster data. The first image and the second image will be described later. The print data may be data stored in the memory unit 42. The print data may also be binary or more data for instructing whether or not to eject ink droplets from the ejection head 30. Furthermore, the print data may be RGB value data before being converted into the binary or more data.

The memory unit 42 is a storage medium accessible by the calculation unit 41, and is composed of, for example, a RAM and a ROM. The RAM temporarily stores various data. Examples of this data include print data and data converted by the calculation unit 41. The ROM stores programs for performing various processes, a comparison pattern Pc described below, and tables Ta1 and Ta2 described below. Note that the programs may be stored in a storage medium other than the memory unit 42.

The calculation unit 41 is composed of, for example, a processor such as a CPU and an integrated circuit such as an ASIC. The calculation unit 41 controls the drive element 34 and the conveying motor 22 by executing a program stored in the ROM.

The controller 40 is connected to the drive element 34 via the head drive circuit 44, and outputs a control signal based on the print data to the head drive circuit 44. The head drive circuit 44 generates a drive signal based on the control signal and outputs it to the drive element 34. This causes the drive element 34 to drive in response to the drive signal, and pressure is applied to the ink in the flow path connected to the nozzle 33, causing ink droplets to be ejected from the nozzle 33 onto the print medium W.

The controller 40 is connected to the transport motor 22 via the transport drive circuit 45, and outputs a control signal based on the print data to the transport drive circuit 45. The transport drive circuit 45 outputs a drive signal generated based on this control signal to the transport motor 22. This controls the drive timing, rotation speed, rotation amount, etc. of the transport motor 22, and transports the print medium W forward in the transport direction Df.

The controller 40 executes a printing process that prints an image on the print medium W based on the print data. In this printing process, the controller 40 performs an ejection operation that drives the drive element 34 to eject ink droplets from the nozzle 33 based on the print data, and a transport operation that drives the transport motor 22 to transport the print medium W forward in the transport direction Df. As a result, the ink droplets ejected from the nozzle 33 land on the print medium W, and the ink droplets form dots on the print medium W. An image is formed on the print medium W by a collection of these dots.

Figure 4 shows an example of a first image Gc that includes a code having information and a second image Gn that does not include the code. As shown in Figure 4, the printing device 10 may form the first image Gc and the second image Gn on the printing medium W.

The first image Gc and the second image Gn are formed by one or more dots. The first image Gc includes a code for reading information from reflected light, and examples of such codes include one-dimensional codes such as barcodes and two-dimensional codes such as QR codes (registered trademark). A code reader irradiates the first image Gc with light such as infrared light, and the information contained in the first image Gc is read from the reflected light. Note that while FIG. 4 shows an embodiment in which the first image Gc does not include images other than codes (e.g., letters and symbols), the first image Gc may include images other than codes.

The second image Gn is an image that does not include a code, unlike the first image Gc. Examples of the second image Gn include characters and logos (designed or decorated characters and character strings). The second image Gn is, for example, white characters consisting of "ABC" arranged in a background image formed with halftones.

Here, when using a printing medium W on which ink droplets tend to bleed a lot, a correction may be performed to remove dots from the image in order to prevent a decrease in the accuracy of reading the code contained in an image such as the first image Gc described above. The correction is described below.

FIG. 5A shows image Gc before processing, FIG. 5B shows a comparison between a dot pattern Pd of a predetermined range including selected dot data Dc and a comparison pattern Pc, and FIG. 5C shows image Gc after correction has been performed. Also, FIG. 6A shows an example of image Gd1 formed using halftone, and FIG. 6B shows image Gd2 after correction has been performed on image Gd1 of FIG. 6A. Note that image Gc of FIG. 5A is an example of a portion of second image Gn described in FIG. 4.

The basic flow of the correction is as follows. First, the controller 40 selects at least one of the first dot data corresponding to the dots forming the first image Gc and the second dot data corresponding to the dots forming the second image Gn in the print data acquired from the external device B (hereinafter referred to as the first print data). In this embodiment, the first print data is described in a page description language (PDL: Page Description Language). The controller 40 executes a process to determine whether or not a dot pattern in a predetermined range including the selected dot data, which is the selected dot data, matches a predetermined comparison pattern. If the controller 40 determines in the determination process that the dot pattern does not match the comparison pattern, the controller 40 executes a correction to delete the selected dot data included in the dot pattern from the first print data. On the other hand, if the controller 40 determines that the dot pattern matches the comparison pattern, the controller 40 executes a process to maintain the selected dot data without executing a correction to delete it from the first print data. However, in this embodiment, the correction to the first image Gc is executed regardless of the user's designation, but the user can specify whether or not to correct the second image Gn using the input device 15. In this case, when the user specifies that correction to the second image Gn is not necessary, the controller 40 performs area designation based on predetermined conditions when correcting the first image Gc. Area designation will be described in detail later.

A specific example of the above correction will be described with reference to the drawings. As shown in FIG. 5A, the controller 40 divides the image to be printed based on the first print data into a plurality of cells in a grid pattern so that one cell corresponds to one dot. The controller 40 then sets dot data "1" to cells whose density in the first print data is equal to or greater than a predetermined value, indicating that a dot will be formed. The cells to which the dot data "1" is set are the cells shaded in FIG. 5A. On the other hand, the controller 40 sets blank data "0" to cells whose density in the first print data is less than a predetermined value, indicating that a dot will not be formed. The cells to which the blank data "0" is set are the cells not shaded in FIG. In the following description, for convenience, the position of each cell arranged in a grid pattern will be specified by row and column.

The controller 40 sequentially selects dot data "1" forming the image Gc from the multiple cells in the first print data, and extracts a dot pattern of a predetermined range including the selected dot data (hereinafter referred to as selected dot data) Dc. In FIG. 5A, dot data Dc1 in the cell located in the third row and third column is selected as the selected dot data Dc. Also, in FIG. 5A, a 3x3 dot pattern Pd consisting of the selected dot data Dc and eight dot data surrounding the selected dot data Dc is set as the dot pattern of the predetermined range. Note that the predetermined range of the dot pattern extracted based on the selected dot data Dc is arbitrary and can be changed as appropriate.

Next, as shown in FIG. 5B, the controller 40 determines whether the dot pattern Pd including the selected dot data Dc matches a predetermined comparison pattern Pc. The comparison pattern Pc has, for example, a 3x3 comparison area, and dot data "1" is set in all cells. In FIG. 5B, the dot pattern Pd does not match the comparison pattern Pc. In this case, the controller 40 corrects the selected dot data Dc to blank data Dc1 as shown in FIG. 5C in order to delete the selected dot data Dc from the first print data. Note that reference symbol Pd1 in FIG. 5C indicates the dot pattern after correction, and reference symbol Gc1 indicates the image after correction.

As described above, correction is performed when the dot pattern Pd does not match the comparison pattern Pc. In other words, since the comparison pattern Pc has dot data set in all cells, if even one of the eight cells surrounding the selected dot data Dc has blank data set, the selected dot data Dc is replaced with blank data Dc1.

If the above correction is performed on the second image Gn, a situation will occur in which the correction cannot be performed appropriately because the second image Gn is white text placed in a background image formed in halftone. In other words, if correction is performed on the image Gd1 formed in halftone as shown in Figure 6A, almost all of the multiple black dots that form the image Gd1 will be replaced with blank data, and the corrected image Gd2 will become a white-filled image as shown in Figure 6B.

In this embodiment, when correction is performed on the first image Gc and the second image Gn, the user specifies whether correction on the second image Gn is necessary or not. If the user specifies that correction on the second image Gn is not necessary, the first image Gc is corrected based on a predetermined area specification. Area specification is described below.

Figure 7A shows table Ta1 which stores the conditions for making corrections, and Figure 7B shows table Ta2 which specifies the method of area designation corresponding to the conditions in Figure 7A. As shown in Figure 7A, table Ta1 specifies whether or not correction to the second image Gn is required by the user, and the number N1 of first images Gc and the number N2 of second images Gn in the first print data (i.e., the number N1 of first images Gc and the number N2 of second images Gn to be formed on the print medium W).

The controller 40 acquires correction necessity information indicating whether or not correction should be made to the second image Gn based on a user instruction. In this case, the controller 40 can acquire the output signal from the input device 15 operated by the user as the correction necessity information. If this correction necessity information indicates that correction of the second image Gn is required, that is, if correction of the second image Gn is required in addition to correction of the first image Gc, the controller 40 performs correction on the entire range including the first image Gc and the second image Gn using the method described in FIG. 5 without performing area designation processing based on the table Ta2 shown in FIG. 7B.

On the other hand, if the correction necessity information indicates that correction of the second image Gn is not necessary, the controller 40 executes the following process. That is, the controller 40 executes a process to specify either the first range R1 (FIG. 4), which is the range of dots forming the first image Gc, or the second range R2 (FIG. 4), which is the range of dots forming the second image Gn, based on the table Ta2 defined based on the conditions in the table Ta1. In this case, the controller 40 obtains the position information of the first image Gc and the second image Gn by analyzing the first print data described in the above-mentioned PDL. Note that in this embodiment, the first range R1 and the second range R2 are, for example, square or rectangular.

When correcting only the first image Gc, the controller 40 specifies either the first range R1 or the second range R2 based on the number N1 of the first images Gc and the number N2 of the second images Gn. When the first range R1 is specified, the controller 40 executes correction in the first range R1. In this case, correction is executed on the first image Gc in the first range R1, and correction is not executed on the second image Gn in the second range R2. On the other hand, when the second range R2 is specified, the controller 40 executes a process of maintaining the second range R2 without executing correction. In this case as well, correction is executed on the first image Gc in the first range R1, and correction is not executed on the second image Gn in the second range R2. In other words, when performing correction on the first image Gc based on correction necessity information that indicates that correction of the second image Gn is not necessary, either a first range R1, which is a range including the first image Gc to be corrected, or a second range R2, which is a range including the second image Gn to be not corrected, is specified based on the number N1 of first images Gc and the number N2 of second images Gn.

The controller 40 also executes the following process. That is, the controller 40 executes a process to determine whether the number N1 of first images Gc in the first print data is equal to or less than the threshold value Nt, and to determine whether the number N2 of second images Gn is equal to or less than the threshold value Nt.

Returning to table Ta1, when the correction necessity information indicates that correction of the second image Gn is not necessary and the controller 40 determines that the number N2 of the second images Gn is equal to or less than the threshold value Nt, the controller 40 designates an area in which correction is not to be performed. In other words, the controller 40 designates the second range R2.

In table Ta1, when the correction necessity information indicates that correction of the second image Gn is not necessary, and when the number N2 of the second images Gn is determined to be greater than the threshold value Nt and the number N1 of the first images Gc is determined to be equal to or less than the threshold value Nt, the controller 40 designates the area in which correction is to be performed. In other words, the controller 40 designates the first range R1.

In table Ta1, when the correction necessity information indicates that correction of the second image Gn is not necessary, and when it is determined that the number N2 of the second images Gn exceeds the threshold value Nt and the number N1 of the first images Gc also exceeds the threshold value Nt, the controller 40 designates the area in which correction is to be performed. In other words, the controller 40 designates the first range R1.

Figure 8 is a flowchart showing the printing process. As shown in Figure 8, first, the controller 40 acquires the first print data for forming the first image Gc and the second image Gn on the printing medium W from the external device B or the input device 15 (step S1).

Next, the controller 40 selects at least one of the first dot data corresponding to the dots forming the first image Gc and the second dot data corresponding to the dots forming the second image Gn from the acquired first print data (step S2). The controller 40 then determines whether or not to perform correction based on the determination result as to whether or not the dot pattern Pd in a predetermined range including the selected dot data Dc matches a predetermined comparison pattern Pc (step S3).

The controller 40 specifies either the first range R1 or the second range R2 based on the table Ta2 (step S4). If the first range R1 is not specified, that is, if the second range R2, which is the range in which correction is not performed, is specified (No in step S5), the controller 40 performs correction on the first image Gc in the first range R1 (step S6). In this case, correction is not performed on the second image Gn in the second range R2.

On the other hand, when the first range R1 is specified, that is, when the range for which correction is to be performed is specified (No in step S5), the controller 40 does not perform correction on the second image Gn in the second range R2 and maintains it (step S7). In this case, correction is performed on the first image Gc in the first range R1.

After the processing of step S6 and after the processing of step S7, the controller 40 executes a process of ejecting droplets from the ejection head 30 onto the print medium W based on the second print data obtained by correcting or maintaining the first print data, thereby forming a first image Gc and a second image Gn on the print medium W (step S8).

Here, we will explain variations in area designation. Figure 9A is a diagram showing an intermediately arranged image Gm located between two first images Gc, and Figure 9B is a diagram for explaining overlay, which is an area designation when correcting the first image Gc and intermediately arranged image Gm in Figure 9A.

The first print data may include, for example, eight or more first images Gc. In the example of FIG. 9A, three images are shown as the first images Gc: a first image Gc1, a first image Gc2, and an intermediate image Gm. For example, the first image Gc2 is arranged apart from the first image Gc1 in the transport direction Df. The intermediate image Gm is a first image Gc different from the first image Gc1 and the first image Gc2. The intermediate image Gm is arranged between the first image Gc1 and the first image Gc2 in the transport direction Df. A part of the intermediate image Gm overlaps with a part of the first image Gc1 in the extension direction Ds. The other part of the intermediate image Gm overlaps with a part of the first image Gc2 in the extension direction Ds. The second image Gn1 is arranged to the right of the first image Gc1, and the second image Gn2 is arranged to the left of the first image Gc2.

The controller 40 specifies the first range R1a for one of the first images Gc1, and specifies the first range R1b for the other of the first images Gc2. In this case, a part of the intermediately arranged image Gm is included in the one of the first ranges R1a specified for one of the first images Gc1, and the other of the first ranges R1b specified for the other of the first images Gc2 includes all of the intermediately arranged image Gm except for the part. In this case, the controller 40 omits the specification of the first range for the intermediately arranged image Gm, as shown in FIG. 9B. Therefore, in the case of the example of FIG. 9A, the controller 40 only needs to specify two first ranges R1 (i.e., the first range R1a and the first range R1b) for the three first images Gc (i.e., the first image Gc1, the first image Gc2, and the intermediately arranged image Gm).

As described above, according to the printing device 10 of this embodiment, one of the first range R1 for performing correction that does not reduce the accuracy of reading the code and the second range R2 for not performing the correction is specified. When the first range R1 is specified, the first image Gc in the first range R1 is corrected, and the second image Gn in the second range R2 is maintained without being corrected. On the other hand, when the second range R2 is specified, the first image Gc in the first range R1 is corrected, and the second image Gn in the second range R2 is maintained without being corrected. This makes it possible to limit the range in which correction is performed. In other words, by specifying the range in which correction is desired to be performed as the first range R1, it is possible to indirectly specify the second range R2, which is the range in which correction is desired to be avoided, and by specifying the second range R2, it is possible to directly specify the range in which correction is desired to be avoided. This makes it possible to perform correction in a state excluding the second image Gn in which correction is desired to be avoided. Therefore, it is possible to print on the print medium W without degrading image quality based on the second print data that includes the second image Gn for which correction is to be avoided.

In addition, in this embodiment, when it is determined that the dot pattern Pd matches the comparison pattern Pc, the selected dot data Dc is maintained without being corrected to be deleted from the first print data. In other words, correction is performed when the dot pattern Pd does not match the comparison pattern Pc. That is, if there is even one cell, for example, among eight cells surrounding the selected dot data Dc, in which blank data is set, a correction is performed to replace the selected dot data Dc with blank data Dc1. This eliminates the need for as many comparison patterns as you want to match with the surrounding dot data in order to ensure that there are many cases in which the selected dot data Dc is corrected.

In addition, in this embodiment, the controller 40 acquires correction necessity information for the second image Gn based on the user's instruction. This allows the user to determine whether or not correction of the second image Gn is necessary based on the user's wishes.

In addition, in this embodiment, when the correction necessity information indicates that correction is necessary, the controller 40 performs correction on the entire range including the first image Gc and the second image Gn without performing range designation processing. This allows correction to be performed on the second image Gn as well as the first image Gc if the user so desires. Also, because range designation processing is no longer necessary, memory usage can be reduced.

In addition, in this embodiment, when the correction necessity information indicates that correction is not necessary and it is determined that the number N2 of second images Gn is equal to or less than the threshold value Nt, the controller 40 specifies a second range R2, which is an area where correction is not performed, in the range specification process. After the range is specified, correction is performed on the first images Gc in the first range R1, and correction is not performed on the second images Gn in the second range R2. In this way, by specifying the second range R2 for the relatively fewer number of second images Gn, it is possible to reduce the number of specified ranges. This makes it possible to reduce memory usage.

In addition, in this embodiment, when the correction necessity information indicates that correction is not necessary and the number N2 of second images Gn is determined to exceed the threshold value Nt and the number N1 of first images Gc is determined to be equal to or less than the threshold value Nt, the controller 40 specifies the first range R1, which is the area to be corrected. After the range is specified, correction is performed on the first images Gc in the first range R1, and correction is not performed on the second images Gn in the second range R2. In this way, by specifying the first range R1 for the relatively fewer number of first images Gc, the number of specified ranges can be reduced. This makes it possible to reduce memory usage.

In addition, in this embodiment, when the correction necessity information indicates that correction is not necessary and the number N2 of second images Gn is determined to exceed the threshold value Nt and the number N1 of first images Gc is determined to exceed the threshold value Nt, the controller 40 specifies the first range R1 in the specification process. In this case, by specifying the first range R1, which is the area to be corrected, it is possible to minimize the risk that the second range R2 will be specified due to a malfunction and correction will be performed on the second images Gn in the second range R2.

Furthermore, in this embodiment, if a portion of the intermediately placed image Gm is included in one first range R1a specified for one first image Gc1, and the other first range R1b specified for the other first image Gc2 includes all but the portion of the intermediately placed image Gm, the following process is executed. That is, the controller 40 omits the specification of the first range for the intermediately placed image Gm. This allows the controller 40 to specify only two first ranges R1 for, for example, three first images Gc. This makes it possible to reduce the amount of processing and memory usage of the controller 40.

(Modification)
The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present invention. For example, the following modifications are possible.

The processing performed by the printing device 10 in the above embodiment may be divided between a computer 51 and the printing device 10 in the printing system 50 described below. Figure 10 is a block diagram showing the configuration of a printing system 50 according to one embodiment of the present invention.

As shown in FIG. 10, the printing system 50 includes a computer 51 and a printing device 10. The computer 51 includes a first controller 52. The printing device 10 includes a head 30 that ejects ink droplets onto a print medium W, and a second controller 46. The first controller 52 acquires first print data for forming a first image Gc including a code having information and a second image Gn not including a code on the print medium W by dots formed by landing ink droplets on the print medium W. The first controller 52 selects at least one of the first dot data corresponding to the dots forming the first image Gc and the second dot data corresponding to the dots forming the second image Gn in the acquired first print data. The first controller 52 also specifies one of the first range R1, which is the range of dots forming the first image Gc, and the second range R2, which is the range of dots forming the second image Gn. When the first range R1 is specified, the first controller 52 performs correction in the first range R1, and when the second range R2 is specified, the first controller 52 maintains the second range R2 without performing correction. In the correction, the first controller 52 determines whether or not the dot pattern Pd in a predetermined range including the selected dot data Dc matches a predetermined comparison pattern Pc. When the dot pattern Pd does not match the comparison pattern Pc, the first controller 52 performs correction to delete the selected dot data Dc from the first print data. On the other hand, when the dot pattern Pd matches the comparison pattern Pc, the first controller 52 maintains the first print data without performing correction to delete the selected dot data Dc from the first print data. Then, the second controller 46 executes a process of forming the first image Gc and the second image Gn on the print medium W by ejecting ink droplets from the ejection head 30 onto the print medium W based on the second print data obtained by performing correction or maintenance on the first print data.

The first controller 52 has a first calculation unit 53, a first memory unit 54, and a first interface 55. The first interface 55 is connected to the printing device 10 and transmits second print data to the printing device 10. The first memory unit 54 is accessible by the first calculation unit 53 and is composed of, for example, RAM and ROM. The first calculation unit 53 performs processing similar to that performed by the calculation unit 41, and transmits the second print data to the printing device 10 via the first interface 55.

The second controller 46 has a second calculation unit 47, a second memory unit 48, and a second interface 49. The second interface 49 receives the second print data sent from the computer 51. The second calculation unit 47 executes a program stored in the second memory unit 48 to perform printing processing based on the second print data. Note that the functions of the other components in the printing device 10 in FIG. 10 are the same as the functions of the components with the same reference numerals in the printing device 10 in FIG. 3 described above, and therefore will not be described here.

In the above embodiment, the ejection head 30 is a line head, but this is not limited to this. The printing device 10 may be equipped with a carriage on which the ejection head 30 is mounted, and a serial head method may be used in which the carriage moves the ejection head 30 in the extension direction Ds.

In addition, in the above embodiment, the printing device 10 does not need to be equipped with a transport device 20 that transports the print medium W in the transport direction Df. In this case, a method in which the ejection head 30 moves relative to the print medium W may be used.

The above description of the embodiment should be construed as merely an example, and is provided for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. The details of the structure and/or function may be substantially changed without departing from the spirit of the present invention.

REFERENCE SIGNS LIST 10 Printing device 30 Discharge head 40 Controller 46 Second controller 50 Printing system 51 Computer 52 First controller Dc Selected dot data Gc, Gc1, Gc2 First image Gm Intermediate arrangement image Gn, Gn1, Gn2 Second image Pc Comparison pattern Pd Dot pattern R1, R1a, R1b First range R2 Second range W Printing medium

Claims (12)

An ejection head that ejects droplets onto a print medium;
A controller,
The controller:
A process of acquiring first print data for forming a first image including a code having information and a second image not including the code on the printing medium by dots formed by landing the droplets on the printing medium;
a process of selecting, from the acquired first print data, at least one of first dot data corresponding to dots forming the first image and second dot data corresponding to dots forming the second image, and determining whether or not to perform a correction to delete the selected dot data from the first print data based on a dot pattern of a predetermined range including the selected dot data, which is the selected dot data, and a predetermined comparison pattern;
A process of designating one of a first range, which is a range of dots forming the first image, and a second range, which is a range of dots forming the second image;
a process of performing the correction in the first range when the first range is designated, and maintaining the second range without performing the correction when the second range is designated;
A printing device that executes a process of ejecting the droplets from the ejection head onto the printing medium based on second printing data obtained by performing the correction or maintenance on the first printing data, thereby forming the first image and the second image on the printing medium. The controller:
In the process of determining whether or not to perform the correction, it is determined whether or not the dot pattern matches the comparison pattern;
2. The printing device according to claim 1, wherein, when it is determined that the dot pattern matches the comparison pattern, a process is executed to maintain the selected dot data without performing a correction to delete the selected dot data from the first print data. The printing device according to claim 1, wherein the controller acquires correction necessity information regarding whether or not to perform the correction on the second image based on a user instruction. The printing device according to claim 3, wherein the controller executes a process to determine whether the number of the second images in the first print data is equal to or less than a threshold value. The printing device according to claim 4, wherein the controller executes a process to determine whether the number of the first images in the first print data is equal to or less than the threshold value. The printing device according to claim 3, wherein the controller, when the correction necessity information indicates that the correction is necessary, performs the correction on the entire range including the first image and the second image without performing the specified process. The printing device according to claim 4, wherein the controller specifies the second range in the specification process when the correction necessity information indicates that the correction is unnecessary and when it is determined that the number of the second images is equal to or less than a threshold value. The printing device according to claim 5, wherein the controller specifies the first range in the specification process when the correction necessity information indicates that the correction is unnecessary and when it is determined that the number of the second images exceeds the threshold value and when it is determined that the number of the first images is equal to or less than the threshold value. The printing device according to claim 5, wherein the controller specifies the first range in the specification process when the correction necessity information indicates that the correction is unnecessary and when it is determined that the number of the second images exceeds the threshold value and when it is determined that the number of the first images exceeds the threshold value. the first print data includes three or more first images;
A printing device as described in claim 9, wherein when the controller specifies the first range in the designation process, if one of the first ranges specified for one of the first images includes a portion of an intermediately placed image that is a first image different from the one of the first images, and if the other of the first ranges specified for the other of the first images includes all of the intermediately placed image other than the portion, the controller omits designation of the first range for the intermediately placed image. A printing system including a computer and a printing device,
The computer includes a first controller,
The printing device includes an ejection head that ejects droplets onto a print medium, and a second controller.
The first controller is
A process of acquiring first print data for forming a first image including a code having information and a second image not including the code on the printing medium by dots formed by landing the droplets on the printing medium;
a process of selecting, from the acquired first print data, at least one of first dot data corresponding to dots forming the first image and second dot data corresponding to dots forming the second image, and determining whether or not to perform a correction to delete the selected dot data from the first print data based on a dot pattern of a predetermined range including the selected dot data, which is the selected dot data, and a predetermined comparison pattern;
A process of designating one of a first range, which is a range of dots forming the first image, and a second range, which is a range of dots forming the second image;
a process of performing the correction in the first range when the first range is designated, and a process of maintaining the second range without performing the correction in the second range when the second range is designated;
The second controller is
A printing system that performs a process of ejecting droplets from the ejection head onto the printing medium based on second printing data obtained by performing the correction or maintenance on the first printing data, thereby forming the first image and the second image on the printing medium. obtaining first print data for forming a first image including a code having information and a second image not including the code on a print medium by dots formed by landing droplets on the print medium;
selecting at least one of first dot data corresponding to dots forming the first image and second dot data corresponding to dots forming the second image from the acquired first print data, and determining whether or not to perform a correction to delete the selected dot data from the first print data based on a dot pattern of a predetermined range including the selected dot data, which is the selected dot data, and a predetermined comparison pattern;
designating one of a first range, which is a range of dots forming the first image, and a second range, which is a range of dots forming the second image;
When the first range is designated, the correction is performed within the first range, and when the second range is designated, the correction is not performed within the second range and is maintained;
A printing method in which the first image and the second image are formed on the printing medium by ejecting the droplets from an ejection head onto the printing medium based on second printing data obtained by performing the correction or maintenance on the first printing data.

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