Apparatus, program, and method for dispensing liquids

Abstract

When an image contains different image types, the image formation speed is improved while maintaining the quality of the image formation. [Solution] The system comprises a liquid ejection unit that selectively ejects liquid with each scan to form an image on a recording medium, a mask pattern determination unit that determines a mask pattern to determine whether or not to eject liquid from the liquid ejection unit during scanning, depending on the image type of the image data corresponding to the image position when there is a mixture of image types covering the image data area, a rendering data generation unit that rearranges and converts the image data into data units to be ejected in one scan and generates rendering data with the ejection data restricted by the determined mask pattern, and a control unit that performs image formation. The mask pattern determination unit increases the number of scans using the mask pattern for forming an image in a high-resolution area compared to the number of scans using the mask pattern for forming an image in a low-resolution area, out of the total number of scans to form an image in the entire area.

Description

Technical Field

[0001] The present invention relates to an apparatus for discharging a liquid, a program, and a liquid discharging method.

Background Art

[0002] Conventionally, in an inkjet printer using an inkjet method, for example, in printing (image formation) in a text area, printing is performed with a small number of liquid discharges to shorten the printing time, and in printing (image formation) in an image area, the number of liquid discharges is increased and the printing time becomes longer, but the image quality is improved. Such a technique is known.

[0003] Patent Document 1 discloses a technique for shortening the printing time by performing control to increase the head scanning speed for printing (image formation) in the text area and decrease the head scanning speed for printing (image formation) in the image area with respect to image data in which a text area and an image area are mixed.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, according to the technique disclosed in Patent Document 1, there are restrictions that all images during one scan are in the text area, or the distance between the text area and the image area is a certain distance. That is, according to the technique disclosed in Patent Document 1, there is a problem that it is difficult to improve the image formation speed for an image in which the text area and the image area are adjacent.

[0005] The present invention has been made in view of the above, and an object thereof is to improve the image formation speed while maintaining the quality of image formation when different image types are included in an image.

Means for Solving the Problems

[0006] To solve the above-mentioned problems and achieve the objective, the present invention comprises: a liquid ejection unit that selectively ejects liquid with each scan that sequentially moves the image formation position to form an image on a relatively moving recording medium; a mask pattern determination unit that determines a mask pattern to determine whether or not to eject liquid from the liquid ejection unit during scanning, according to the image type of the image data corresponding to the image position when there is a mixture of image types covering the region of the image data that forms the basis of the image to be formed on the recording medium; a rendering data generation unit that rearranges and converts the image data into data units to be ejected in one scan and generates rendering data that restricts the ejection data by the mask pattern determined by the mask pattern determination unit; and a control unit that performs an image formation operation by performing a liquid ejection operation from the liquid ejection unit based on the rendering data, wherein the mask pattern determination unit is characterized in that, of the number of scans to form an image of the entire region, the number of scans using the mask pattern for forming an image of a high-resolution region classified by the image type is greater than the number of scans using the mask pattern for forming an image of a low-resolution region classified by the image type. [Effects of the Invention]

[0007] According to the present invention, when an image contains different types of images, the printing time can be shortened while maintaining the quality of image formation. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view showing the inside of a printing apparatus according to the first embodiment. [Figure 2] Figure 2 is a plan view showing the scanning mechanism of the carriage of the printing device. [Figure 3] Figure 3 is a block diagram showing the hardware configuration of the printing device. [Figure 4] Figure 4 shows an example of image region data generated by the image region generation unit. [Figure 5] Figure 5 shows an example of a mask pattern. [Figure 6] Figure 6 is a flowchart showing the print output processing flow of a printing device. [Figure 7] Figure 7 shows an example of the printout from the first scan. [Figure 8] Figure 8 shows an example of the printout from the second scan. [Figure 9] Figure 9 shows an example of the printout from the third scan. [Figure 10] Figure 10 shows an example of the printout from the fourth scan. [Figure 11] Figure 11 is a flowchart showing the print output processing flow of a printing device when image area data is input in advance. [Figure 12] Figure 12 shows an example of the arrangement of the recording head according to the second embodiment. [Figure 13] Figure 13 shows an example of image region data including color information generated by the image region generation unit. [Figure 14] Figure 14 shows an example of a mask pattern. [Figure 15] Figure 15 shows an example of the printout from the first scan. [Figure 16] Figure 16 shows an example of the printout from the second scan. [Figure 17] Figure 17 shows an example of the printout from the third scan. [Figure 18] Figure 18 shows an example of the printout from the fourth scan. [Figure 19] Figure 19 shows an example of image region data generated by the image region generation unit according to the third embodiment. [Figure 20] Figure 20 shows an example of a mask pattern. [Modes for carrying out the invention]

[0009] Referring to the accompanying drawings below, embodiments of an apparatus for discharging a liquid, a program, and a liquid discharging method will be described in detail. In the embodiments described below, as an example of an apparatus for discharging a liquid to which the present invention is applied, an MFP (Multifunction Peripheral) including a serial head type inkjet printer is exemplified as a printing apparatus. An MFP is generally called a multi-function device having at least two functions among a copying function, a printer function, a scanner function, and a facsimile function.

[0010] (First Embodiment) FIG. 1 is a perspective view showing the interior of a printing apparatus 100 according to the first embodiment in a perspective manner, and FIG. 2 is a plan view showing the scanning mechanism of a carriage 5 included in the printing apparatus 100. The printing apparatus 100 is an inkjet printer that prints on a long recording medium M, which is a roll of printing (image forming) paper.

[0011] As shown in FIGS. 1 and 2, the printing apparatus 100 of the present embodiment includes a carriage 5 that reciprocates in the main scanning direction indicated by arrow A in FIG. 1. The carriage 5 is supported by a main guide rod 3 extending along the main scanning direction A. Further, a connecting piece 5a is provided on the carriage 5. The connecting piece 5a engages with a sub-guide rail 4 provided parallel to the main guide rod 3 to stabilize the posture of the carriage 5.

[0012] As shown in Fig. 2, the carriage 5 is equipped with four recording heads 6m, 6y, 6c, and 6k. The recording head 6y is a recording head that discharges yellow (Y) ink. The recording head 6m is a recording head that discharges magenta (M) ink. The recording head 6c is a recording head that discharges cyan (C) ink. The recording head 6k is a plurality of recording heads that discharge black (Bk) ink. Hereinafter, when collectively referring to these recording heads 6y, 6m, 6c, and 6k, they are called the recording head 6. The recording head 6 is supported by the carriage 5 such that its ejection surface (nozzle surface) faces downward (toward the recording medium M side). The recording head 6 (6y, 6m, 6c, 6k) functions as a liquid ejection unit that selectively ejects liquid (ink) for each scan that sequentially moves the image formation position, and forms an image on the relatively moving recording medium M.

[0013] The cartridge 7, which is an ink supply body for supplying ink to the recording head 6, is not mounted on the carriage 5 but is arranged at a predetermined position within the printing apparatus 100. The cartridge 7 and the recording head 6 are connected by a pipe (not shown), and ink is supplied from the cartridge 7 to the recording head 6 through this pipe.

[0014] The carriage 5 is connected to a timing belt 11 stretched between a driving pulley 9 and a driven pulley 10. The driving pulley 9 rotates by the drive of the main scanning motor 8. The driven pulley 10 has a mechanism for adjusting the distance between itself and the driving pulley 9 and serves to apply a predetermined tension to the timing belt 11. The carriage 5 reciprocates in the main scanning direction A when the timing belt 11 is driven by the drive of the main scanning motor 8. The movement of the carriage 5 in the main scanning direction A is controlled based on, for example, the encoder value obtained when the main scanning encoder sensor 13 provided on the carriage 5 detects the mark on the encoder sheet 14 as shown in Fig. 2.

[0015] Furthermore, the printing apparatus 100 of this embodiment includes a maintenance mechanism 15 for maintaining the reliability of the recording head 6. The maintenance mechanism 15 performs tasks such as cleaning and capping the ejection surface of the recording head 6 and draining excess ink from the recording head 6.

[0016] As shown in Figure 2, a platen 16 is positioned below the reciprocating path of the carriage 5. The platen 16 supports the recording medium M when ink is ejected from the recording head 6 onto the recording medium M. That is, the recording medium M is intermittently transported in the sub-scanning downstream direction (first direction) indicated by arrow B in Figure 1 by the paper transport unit 38 (see Figure 4), which will be described later. While the transport of the recording medium M in the sub-scanning downstream direction B is stopped, the carriage 5 is moved in the main scanning direction A, and ink is ejected from the nozzle row of the recording head 6 mounted on the carriage 5 onto the recording medium M on the platen 16, thereby forming an image on the recording medium M. After that, the recording medium M on which the image has been formed is further transported in the sub-scanning downstream direction B and dried by the drying heater 17.

[0017] In this embodiment, when performing calibration such as color adjustment, the printing apparatus 100 ejects ink from the recording head 6 onto the recording medium M, forming a color measurement pattern consisting of a group of patches to be measured, and a marker pattern for identifying the position of the color measurement pattern on the recording medium M.

[0018] The printing apparatus 100 of this embodiment includes an imaging unit 20 for measuring the color of a colorimetric pattern formed on a recording medium M.

[0019] The above-mentioned components constituting the printing apparatus 100 of this embodiment are arranged inside the outer casing 1. The outer casing 1 is provided with a cover member 2 that can be opened and closed. When performing maintenance on the printing apparatus 100 or when a jam occurs, the cover member 2 can be opened to perform work on the components located inside the outer casing 1.

[0020] Next, the hardware configuration of the printing apparatus 100 of this embodiment will be described with reference to Figure 3. Figure 3 is a block diagram showing the hardware configuration of the printing apparatus 100.

[0021] As shown in Figure 3, the printing device 100 is connected to a PC (Personal Computer) 200. The printing device 100 includes an image forming mechanism 30.

[0022] The image forming mechanism 30 comprises a control unit 31, a ROM (Read Only Memory) 32, a RAM (Random Access Memory) 33, an operation unit 34, an image processing unit 35, and a reading device 50. The control unit 31 is a control device such as a CPU (Central Processing Unit), and controls the entire printing device 100 by loading the program stored in the ROM 32 into the RAM 33 and executing it.

[0023] The program executed by the printing apparatus 100 of this embodiment is provided as a file in an installable or executable format, recorded on a computer-readable recording medium such as a CD-ROM, flexible disk (FD), CD-R, or DVD (Digital Versatile Disc).

[0024] Furthermore, the program executed by the printing device 100 of this embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. Alternatively, the program executed by the printing device 100 of this embodiment may be provided or distributed via a network such as the Internet.

[0025] Alternatively, the program executed by the printing device 100 of this embodiment may be pre-installed and provided in ROM or the like.

[0026] The program executed by the printing apparatus 100 of this embodiment has a modular configuration including the parts shown in Figure 3 (mask pattern determination unit 31a, rendering data generation unit 31b). In actual hardware, the CPU (processor) reads the program from the storage medium and executes it, loading the parts onto the main memory, and generating the mask pattern determination unit 31a and the rendering data generation unit 31b on the main memory.

[0027] The control unit 31 transmits the image data received from the PC 200 or the reader 50 to the image processing unit 35.

[0028] The image processing unit 35 processes the image data sent from the control unit 31. More specifically, the image processing unit 35 performs image processing for printing. The image processing unit 35 also includes an image region generation unit 35a that generates image region data by determining the type of image information according to the image position based on the image data. In this embodiment, the image region generation unit 35a determines the image region (text region, image region) as the image type information. A text region is a low-resolution region composed of text such as characters. An image region is a high-resolution region composed of images such as photographs. The method for determining the image region (text region, image region) is an existing technology, so its explanation is omitted.

[0029] Here, Figure 4 shows an example of image region data generated by the image region generation unit 35a. The image region example shown in Figure 4 is an example in which the image is composed of multiple types of information (text region, image region). The image region generation unit 35a determines that the area inside the dotted line region shown in Figure 4 is the "image region" and determines that the area outside the dotted line region shown in Figure 4 is the "text region," and generates image region data accordingly.

[0030] The control unit 31 comprises the mask pattern determination unit 31a and the rendering data generation unit 31b. The control unit 31 receives image data and image region data corrected by the image processing unit 35, and performs mask pattern data determination in the mask pattern determination unit 31a and rendering data generation in the rendering data generation unit 31b.

[0031] The mask pattern determination unit 31a determines mask pattern data according to the image region data. The mask pattern determination unit 31a transmits the image data and mask pattern data to the rendering data generation unit 31b.

[0032] Here, Figure 5 shows an example of a mask pattern. As shown in Figure 5, the mask pattern determination unit 31a determines the mask pattern data according to the image area data. The example shown in Figure 5 is an example of a mask pattern for an image area and a text area.

[0033] The mask pattern example shown in Figure 5 is one in which output is performed for all scans in the "image area," but not for scans 1-3 in the "text area," and output is performed only for scan 4. From scan 5 onwards, masking is repeatedly applied using the mask pattern from scans 1-4. In the mask pattern example shown in Figure 5, the sub-scan resolution of the "text area" is half that of the "image area."

[0034] In other words, the mask pattern determination unit 31a increases the number of scans using the mask pattern for forming an image of a high-resolution region (image region) classified by image type, compared to the number of scans using the mask pattern for forming an image of a low-resolution region (text region) classified by image type, out of the total number of scans to form an image of the entire region.

[0035] The rendering data generation unit 31b performs image processing for printing and rendering of image data for the printing device 100, and generates rendering data to be ejected with each scan based on the mask pattern. More specifically, the rendering data generation unit 31b rearranges and converts the data into data units to be ejected per scan according to the number of interlaces and the number of passes, and restricts the ejected data using the mask pattern data.

[0036] The control unit 31 performs image formation by ejecting ink from the recording head 6 in accordance with the movement of the carriage 5 in the main scanning direction A, based on the rendering data.

[0037] The image forming mechanism 30 includes a carriage 5 equipped with a recording head 6, which is an image forming unit that ejects ink; a main scanning driver 36; a head driver 37; and a main scanning motor 8 that drives the carriage 5. The carriage 5 is equipped with a main scanning encoder sensor 13. The control unit 31 functions as a moving means that drives the main scanning motor 8 via the main scanning driver 36 to move the carriage 5 along the platen 16. The control unit 31 controls ink ejection at the recording head 6 via the head driver 37.

[0038] The image forming mechanism 30 comprises a reading device 50 and a document transport driver 44. The reading device 50 comprises a color image sensor (CIS: Contact Image Sensor) 51 using a solid-state image sensor, a light source (LED: Light-Emitting Diode) 52, and a document transport unit 53. The control unit 31 controls the reading of the document image by the color image sensor 51 and the light source 52 for the document transported by the document transport unit 53 driven via the document transport driver 44.

[0039] The image forming mechanism 30 includes a paper transport unit 38, a sub-scanning driver 39, a suction fan 40, a cutting unit 41, a cutter motor driver 42, and an end detection unit 43 which is a reflection sensor. The control unit 31 functions as a transport means that drives the paper transport unit 38 via the sub-scanning driver 39 to transport the recording medium M in a direction perpendicular to the carriage movement direction. The control unit 31 drives the cutting unit 41 via the cutter motor driver 42 to cut the recording medium M. The control unit 31 drives the suction fan 40 when the recording medium M is set to attract the recording medium M to the platen 16. The control unit 31 detects the end of the paper (end) of the recording medium M using the end detection unit 43 which functions as an end detection means.

[0040] Next, we will explain the functions that the printing device 100 performs by operating according to the program.

[0041] Here, Figure 6 is a flowchart showing the print output processing flow of the printing device 100. As shown in Figure 6, when the control unit 31 receives image data from the PC 200 or the reader 50 during copy printing or printer printing, it transfers it to the image processing unit 35 (step S1).

[0042] Next, the image processing unit 35 performs various image processing operations on the image data (step S2). More specifically, the image region generation unit 35a of the image processing unit 35 determines the image region (image type information) corresponding to the image position based on the image data sent from the control unit 31, generates image region data, and sends it to the control unit 31 (step S2).

[0043] Next, the mask pattern determination unit 31a of the control unit 31 determines the mask pattern data according to the image region data and transmits the image data and mask pattern data to the rendering data generation unit 31b (step S3).

[0044] Next, the rendering data generation unit 31b of the control unit 31 rearranges and converts the data into data units to be ejected in one scan, and generates rendering data by restricting the ejected data with mask pattern data (step S4).

[0045] Next, the control unit 31 performs scanning of the recording head 6 and ink ejection control of the recording head 6 according to the rendering data, and executes a single scan print process (step S5).

[0046] Next, after the scanning printing process is performed, the control unit 31 controls the paper transport unit 38 to transport the recording medium M in the sub-scanning direction for one scan (step S6).

[0047] The control unit 31 repeats steps S5 to S6 until the printing process is completed (step S7).

[0048] Figures 7 to 10 show examples of printing regions corresponding to image region data. Here, we will show printing examples based on the image region example shown in Figure 4.

[0049] Figure 7 shows an example of printing from the first scan. As shown in Figure 7, the printing device 100 uses the mask pattern for the image area with scan number "4N+1" in the mask pattern example shown in Figure 5, and ejects ink only from the image area, targeting the scanning of the recording head 6. The mask pattern is applied repeatedly, starting from the top left of the image.

[0050] Figure 8 shows an example of printing from the second scan. As shown in Figure 8, the printing device 100 uses the mask pattern for the image area of ​​scan number "4N+2" in the mask pattern example shown in Figure 5, and ejects ink only from the image area, targeting the scanning of the recording head 6.

[0051] Figure 9 shows an example of printing from the third scan. As shown in Figure 9, the printing device 100 uses the mask pattern for the image area of ​​scan number "4N+3" in the mask pattern example shown in Figure 5, and targets only the image area for scanning by the recording head 6, ejecting ink from the recording head 6.

[0052] Figure 10 shows an example of printing from the fourth scan. As shown in Figure 10, the printing device 100 uses the mask pattern for the image area and the mask pattern for the text area with scan number "4N+4" in the mask pattern example shown in Figure 5, and ejects ink, targeting the entire area (image area + text area) for scanning by the recording head 6.

[0053] By applying this mask pattern, a region with a shorter scanning width for the recording head 6 is created, thereby improving the printing speed.

[0054] As described above, according to this embodiment, when an image contains different image types (text areas, image areas), by applying different mask patterns according to the image type (text areas, image areas), the number of head scans is increased only for image information that requires frequent printing, and the number of printing cycles for text information in areas where printing speed is prioritized is reduced, thereby reducing the head scan width. This makes it possible to shorten the printing time while maintaining the quality of image formation.

[0055] More specifically, in the case where the image contains different image types (text area, image area), in the above-described embodiment, Number of times to print the text area: 1 per 4 scans Number of times to print around the image area: 4 times per scan This type of printing allows for a reduction in head scanning time.

[0056] According to this embodiment, since it does not involve changing the head scanning speed during printing, speed improvements can be expected even under conditions where text areas and image areas are adjacent. Furthermore, according to this embodiment, when printing the text area, the image area is printed during the same scanning process, so no unnecessary printing operations occur.

[0057] In this embodiment, the image region generation unit 35a of the image processing unit 35 generates image region data by determining the image region (image type information) corresponding to the image position based on the image data sent from the control unit 31, but this is not the only possible configuration.

[0058] For example, during copy printing or printer printing, image area data may be input in advance in addition to image data. Here, Figure 11 is a flowchart showing the print output processing flow of the printing device 100 when image area data is input in advance. As shown in Figure 11, when the control unit 31 receives image data and image area data from the PC 200 or reader 50 during copy printing or printer printing, it transfers them to the image processing unit 35 (step S11). Subsequently, the image processing unit 35 performs various image processing on the image data (step S2).

[0059] Next, the mask pattern determination unit 31a of the control unit 31 determines the mask pattern data according to the image region data and transmits the image data and mask pattern data to the rendering data generation unit 31b (step S3).

[0060] Next, the rendering data generation unit 31b of the control unit 31 rearranges and converts the data into data units to be ejected in one scan, and generates rendering data by restricting the ejected data with mask pattern data (step S4).

[0061] Next, the control unit 31 performs scanning of the recording head 6 and ink ejection control of the recording head 6 according to the rendering data, and executes a single scan print process (step S5).

[0062] Next, after the scanning printing process is performed, the control unit 31 controls the paper transport unit 38 to transport the recording medium M in the sub-scanning direction for one scan (step S6).

[0063] The control unit 31 repeats steps S5 to S6 until the printing process is completed (step S7).

[0064] Thus, since the PC200 or reader 50 generates and inputs image area data in addition to image data, the determination of the image area within the printing device 100 can be omitted.

[0065] (Second Embodiment) Next, a second embodiment will be described.

[0066] The second embodiment differs from the first embodiment in that it includes color information (monochrome image, color image) for the image type (text area, image area). In the following description of the second embodiment, the parts that are the same as those of the first embodiment will be omitted, and the parts that differ from the first embodiment will be described.

[0067] Here, Figure 12 shows an example of the arrangement of the recording head 6 according to the second embodiment. As shown in Figure 12, the recording head 6 of the printing apparatus 100 in this embodiment has a configuration in which two recording heads 6k-1 and 6k-2 are arranged in a staggered pattern as recording heads 6k that eject black (Bk) ink. The recording head 6 has N+1 nozzles, from nozzle 1 to nozzle N.

[0068] In other words, the recording head 6 has a head configuration in which only heads of a specific color (black (Bk) ink) (recording heads 6k-1, 6k-2) are arranged in a staggered pattern, resulting in a head configuration with a larger image formation width than the head configuration of color heads (recording heads 6m, 6y, 6c).

[0069] With this configuration, the recording head 6 ejects two recording heads 6k-1 and 6k-2 together when forming images in the monochrome image region, and ejects using recording heads 6k-2, 6y, 6m, and 6c when forming images in the color image region. This makes it possible to form images in the monochrome image region using a sub-scan length twice that of the color image region.

[0070] In addition, the image region generation unit 35a of the image processing unit 35 determines the image type information (monochrome image, color image) along with the image region as image region information according to the image position based on the image data sent from the control unit 31, generates image region data, and sends it to the control unit 31.

[0071] Here, Figure 13 shows an example of image region data including color information generated by the image region generation unit 35a. The example of an image region including color information shown in Figure 13 is an example in which the image is composed of four types of image regions: multiple image regions (text region, image region) and multiple color information (monochrome image, color image). The image region generation unit 35a determines that the area inside the dotted line region shown in Figure 13 is an "image region" and the area outside the dotted line region shown in Figure 13 is a "text region". Furthermore, the image region generation unit 35a determines that the left half of the image shown in Figure 13 is a "color image" and the right half is a "monochrome image".

[0072] As described in the first embodiment, color information and image area data may be input in advance in addition to image data when copying or printing.

[0073] The mask pattern determination unit 31a determines different mask pattern data for color images and monochrome images according to the image area data.

[0074] Here, Figure 14 shows an example of a mask pattern. As shown in Figure 14, the mask pattern determination unit 31a determines the mask pattern data according to the image area data. The example shown in Figure 14 is an example of a mask pattern for a color image area, a monochrome image area, a color text area, and a monochrome text area.

[0075] The mask pattern example shown in Figure 14 is one in which output is performed for all scans in the "image area," but not for scans 1-3 in the "text area," and output is performed only for scan 4. From scan 5 onwards, masking is repeatedly applied using the mask pattern from scans 1-4. In the mask pattern example shown in Figure 14, the sub-scan resolution of the "text area" is half that of the "image area."

[0076] The printing conditions for each image area are as follows: Color image area ···1 pass 1 / 2 interlaced Monochrome image area ···1 pass 1 / 2 interlaced Color text area ···1 pass 1 / 1 interlaced Monochrome text area ···1 pass 1 / 1 interlaced

[0077] Figures 15 to 18 show examples of printing regions corresponding to image region data. Here, we will show printing examples based on the image region example shown in Figure 4.

[0078] Figure 15 shows an example of the first scan print. As shown in Figure 15, the printing device 100 uses the mask pattern for the color image area with scan number "4N+1" in the mask pattern example shown in Figure 14, and ejects ink only to the color image area, targeting scanning by the recording head 6. The mask pattern is applied repeatedly, starting from the top left of the image.

[0079] Figure 16 shows an example of printing from the second scan. As shown in Figure 16, the printing device 100 uses the mask pattern for the color image area and color text area of ​​scan number "4N+2" in the mask pattern example shown in Figure 14, and ejects ink only to the color image area and color text area, targeting scanning by the recording head 6.

[0080] Figure 17 shows an example of printing from the third scan. As shown in Figure 17, the printing device 100 uses the mask pattern for the color image area and monochrome image area of ​​scan number "4N+3" in the mask pattern example shown in Figure 14, and targets only the color image area and monochrome image area for scanning, ejecting ink from the recording head 6.

[0081] Figure 18 shows an example of printing after the fourth scan. As shown in Figure 18, the printing device 100 uses the mask pattern for color and monochrome image areas and the mask pattern for color and monochrome text areas with scan number "4N+4" in the mask pattern example shown in Figure 14, and ejects ink by scanning the entire area (color image area + monochrome image area + color text area + monochrome text area) with the recording head 6.

[0082] By providing different mask patterns for color and monochrome printing, a region with a shorter scanning width for the recording head 6 is created, thereby improving the printing speed.

[0083] (Third embodiment) Next, a third embodiment will be described.

[0084] The third embodiment differs from the first embodiment in that the image types consist of density information (high-density areas, low-density areas). In the following description of the third embodiment, the parts that are the same as those of the first embodiment will be omitted, and the parts that differ from the first embodiment will be described.

[0085] Here, Figure 19 shows an example of image region data generated by the image region generation unit 35a according to the third embodiment. The image region example shown in Figure 19 is an example in which the image is composed of multiple types of information (high density region, low density region). The image region generation unit 35a determines the area inside the dotted line region shown in Figure 19 as "high density" and generates image region data in which the area outside the dotted line region shown in Figure 19 is determined as "low density". The low density region is a low-resolution region. The high density region is a high-resolution region. Note that the method for determining image regions (high density region, low density region) is an existing technology, so an explanation is omitted.

[0086] Here, Figure 20 shows an example of a mask pattern. As shown in Figure 20, the mask pattern determination unit 31a determines the mask pattern data according to the image region data. The example shown in Figure 20 is an example of a mask pattern for a high-density region and a low-density region.

[0087] The mask pattern example shown in Figure 20 is one in which ejection occurs in the "high-density region" during all scans, but in the "low-density region," ejection does not occur in the first to third scans, and ejection occurs only in the fourth scan. From the fifth scan onward, masking is repeatedly applied using the mask pattern from scans 1 to 4. In the mask pattern example shown in Figure 20, the sub-scan resolution in the "low-density region" is half that of the sub-scan resolution in the "high-density region."

[0088] Note that the printing example using the mask pattern shown in Figure 20 is the same as the printing example according to the image type (text area, image area) in the first embodiment, so it is omitted here.

[0089] Thus, according to this embodiment, by including switching based on density information in the image classification, the number of times the image type is printed in low-density areas can be reduced, thereby improving the printing speed.

[0090] In this application, "liquid dispensing device" refers to a device that includes a liquid dispensing head or liquid dispensing unit and drives the liquid dispensing head to dispense liquid. A liquid dispensing device includes not only devices that can dispense liquid onto objects to which liquid can adhere, but also devices that dispense liquid into air or into liquid.

[0091] This "liquid dispensing device" may also include means for feeding, transporting, and dispensing paper onto materials to which liquid can adhere, as well as pre-treatment devices, post-treatment devices, etc.

[0092] For example, "devices that dispense liquids" include image forming machines, which dispense ink to form images on paper, and three-dimensional molding machines, which dispense molding liquid into a powder layer formed in layers to create three-dimensional objects.

[0093] Furthermore, "devices that dispense liquid" are not limited to those that visualize meaningful images such as letters or figures through the dispensed liquid. For example, devices that form patterns that do not have meaning in themselves, or devices that create three-dimensional images, are also included.

[0094] The term "materials to which liquid can adhere" above refers to materials to which liquid can adhere, at least temporarily, including materials that adhere and solidify, or materials that adhere and penetrate. Specific examples include recording media such as paper, recording paper, film, and cloth; electronic components such as electronic circuit boards and piezoelectric elements; powder layers; organ models; and inspection cells. Unless otherwise specified, it includes all materials to which liquid can adhere.

[0095] The materials referred to as "materials to which liquid can adhere" above include paper, thread, fibers, fabrics, leather, metal, plastic, glass, wood, ceramics, etc., as long as liquid can adhere to them, even temporarily.

[0096] Furthermore, the "liquid" is not particularly limited, as long as it has the viscosity and surface tension to be dispensed from the head, but it is preferable that its viscosity becomes 30 mPa·s or less at room temperature and atmospheric pressure, or when heated or cooled. More specifically, it is a solution, suspension, emulsion, etc. containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a functional material such as a surfactant, a biocompatible material such as DNA, amino acids or proteins, calcium, or an edible material such as a natural pigment. These can be used, for example, as inkjet inks, surface treatment liquids, liquids for forming components of electronic elements and light-emitting elements or electronic circuit resist patterns, and material liquids for 3D molding.

[0097] Other examples of "devices that dispense liquids" include processing liquid coating devices that dispense processing liquid onto the surface of paper for purposes such as modifying the surface of the paper, and injection granulation devices that granulate fine particles of raw materials by spraying a composition liquid, in which raw materials are dispersed in a solution, through a nozzle.

[0098] Furthermore, in the terminology used in this application, image formation, recording, printing, copying, printing, and shaping are all considered synonymous. [Explanation of Symbols]

[0099] 6 Liquid discharge part 31 Control Unit 31a Mask pattern determination section 31b Rendering data generation unit 35a Image area generation unit 100 Liquid dispensing device [Prior art documents] [Patent Documents]

[0100] [Patent Document 1] Japanese Patent Publication No. 2003-175587

Claims

1. A liquid ejection unit selectively ejects liquid with each scan, which sequentially moves the image formation position, to form an image on a recording medium that is moving relatively. When there is a mixture of image types in the region of the image data that forms the basis of the image to be formed on the recording medium, a mask pattern determination unit determines a mask pattern that determines whether or not to discharge liquid from the liquid discharge unit during scanning, according to the image type of the image data corresponding to the image position, A rendering data generation unit rearranges and converts the image data into data units to be ejected in one scan, and generates rendering data that restricts the ejected data by the mask pattern determined by the mask pattern determination unit, A control unit performs image formation by dispensing liquid from the liquid dispensing unit based on the rendering data, Equipped with, The mask pattern determination unit increases the number of scans using the mask pattern for forming a high-resolution region classified as an image type compared to the number of scans using the mask pattern for forming a low-resolution region classified as an image type, out of the total number of scans to form an image of the entire region. A device for dispensing liquid characterized by the following.

2. When different image types are mixed in the image data that forms the basis of the image to be formed on the recording medium, the system further includes an image region generation unit that generates image region data indicating the image type of the image data according to the image position, based on the image data. A device for dispensing liquid according to feature 1.

3. The image type relating to the region of the image data is the text region which is the low-resolution region and the image region which is the high-resolution region. A liquid dispensing apparatus according to feature 1 or 2.

4. The aforementioned image type includes the text area, which is the low-resolution area, and the image area, which is the high-resolution area, as well as color information, which includes monochrome images and color images. The aforementioned liquid ejection unit has a head configuration in which the monochrome head configuration is arranged in a staggered pattern, resulting in a head configuration with a larger print width than the color head configuration. The mask pattern determination unit determines different mask patterns for the monochrome image and the color image. A liquid dispensing apparatus according to feature 1 or 2.

5. The image type relating to the region of the image data is the low-density region which is the low-resolution region and the high-density region which is the high-resolution region. A liquid dispensing apparatus according to feature 1 or 2.

6. A computer controls a liquid dispensing device that includes a liquid dispensing unit that selectively dispenses liquid with each scan, which sequentially moves the image formation position, to form an image on a relatively moving recording medium. When there is a mixture of image types in the region of the image data that forms the basis of the image to be formed on the recording medium, a mask pattern determination unit determines a mask pattern that determines whether or not to discharge liquid from the liquid discharge unit during scanning, according to the image type of the image data corresponding to the image position, A rendering data generation unit rearranges and converts the image data into data units to be ejected in one scan, and generates rendering data that restricts the ejected data by the mask pattern determined by the mask pattern determination unit, A control unit performs image formation by dispensing liquid from the liquid dispensing unit based on the rendering data, To make it function as, The mask pattern determination unit increases the number of scans using the mask pattern for forming a high-resolution region classified as an image type compared to the number of scans using the mask pattern for forming a low-resolution region classified as an image type, out of the total number of scans to form an image of the entire region. A program characterized by the following features.

7. A liquid dispensing device comprising a liquid dispensing unit that selectively dispenses liquid with each scan to sequentially move the image formation position and forms an image on a relatively moving recording medium, and a liquid dispensing method in the device, When there is a mix of image types in the region of the image data that forms the basis of the image to be formed on the recording medium, a mask pattern determination step is made to determine a mask pattern that determines whether or not to discharge liquid from the liquid discharge unit during scanning, according to the image type of the image data corresponding to the image position. A rendering data generation step involves rearranging and converting the image data into data units to be ejected in one scan, and generating rendering data that restricts the ejected data using the mask pattern determined in the mask pattern determination step. A control step in which an image is formed by performing a liquid discharge operation from the liquid discharge unit based on the rendering data, Equipped with, The mask pattern determination step involves increasing the number of scans using the mask pattern for forming a high-resolution region classified as an image type compared to the number of scans using the mask pattern for forming a low-resolution region classified as an image type, out of the total number of scans to form an image of the entire region. A liquid dispensing method characterized by the following:

Images