JP2018126993A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily determine an appropriate upper limit value for ink discharge amounts.SOLUTION: The printer comprises: a printing part that prints a test pattern for determining an upper limit value for ink discharge amounts; an imaging part that images a medium for testing having the test pattern printed thereon; a color measuring part that measures color of the medium for testing; and a discharge amount upper limit value determining part that determines an upper limit value for the ink discharge amounts. The discharge amount upper limit value determining part determines the upper limit value for the ink discharge amounts, on the basis of at least either of: at least one non-occurrence upper limit value of a non-occurrence upper limit value as an upper limit value for ink discharge amounts at which ink leakage does not occur, a non-occurrence upper limit value as an upper limit value for ink discharge amounts at which ink bleeding does not occur and a non-occurrence upper limit value as an upper limit value for ink discharge amounts at which ink aggregation does not occur, which are calculated based on information obtained by the imaging part; and a non-occurrence upper limit value as an upper limit value for ink discharge amounts at which color saturation of ink does not occur, which is calculated based on information obtained by the color measuring part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for determining an upper limit value of an ink discharge amount.

  There is a printing apparatus that forms dots on a print medium by ejecting ink from a plurality of nozzles provided in a print head. The amount of ink discharged in such a printing apparatus varies depending on the type of printing medium, the type of ink, and the like even when pixels having the same gradation value are formed. For example, when printing on a relatively glossy print medium, the greater the amount of ink that is ejected, the more ink is collected in the periphery of the ink droplets during the ink drying process and the ink density (the dot group of the print medium is reproduced). A so-called “ink overflow” may occur, in which the color index) increases. For this reason, the ink discharge amount can be suppressed. In addition, for example, when printing on a print medium with relatively low gloss, the discharged ink tends to wet and spread in the process of being absorbed by the print medium, so that “ink bleeding” becomes stronger as the amount of discharged ink increases. Tend. For this reason, the ink discharge amount tends to be suppressed. Therefore, a technique is known in which the ink discharge amount is adjusted in accordance with the type of print medium, thereby suppressing deterioration in the print image quality. In Patent Document 1, as a method of adjusting the ink discharge amount, a print image is printed, and the printed print image is read by a scanner device, and the presence or absence of ink overflow or ink bleeding is measured. A technique for determining the upper limit value of the ink discharge amount is disclosed.

JP2013-201666A

  There are elements that should be avoided in printing, such as ink overflow and ink bleeding, and should be considered when determining the upper limit value of the ink ejection amount (hereinafter referred to as “avoidance target element”). . Here, when the upper limit value of the ink discharge amount is determined so as to avoid a certain avoidance target element, there may be a case where other avoidance target elements cannot be avoided. In such a case, the image quality is deteriorated as a result. However, it is not easy for a user unfamiliar with the printing apparatus to determine an appropriate upper limit value of the ink ejection amount after understanding the relationship between the elements to be avoided. Therefore, a technique that can easily determine an appropriate upper limit value of the ink discharge amount is desired.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

(1) According to an embodiment of the present invention, a printing apparatus is provided. This printing apparatus is a printing apparatus that prints an image by ejecting ink onto a print medium, and includes a printing unit that prints a test pattern for determining an upper limit value of the ink ejection amount, and the test pattern includes: An imaging unit that images the printed test medium, a colorimetric unit that measures the color of the test medium, and an ejection amount upper limit determination unit that determines the upper limit value of the ejection amount of the ink, The discharge amount upper limit determination unit calculates a non-occurrence upper limit as an upper limit of the ink discharge amount that does not cause overflow of the ink, calculated based on imaging information obtained by the imaging unit, and the ink At least one of the non-occurrence upper limit value as the upper limit value of the ink ejection amount at which no ink bleeding occurs and the non-occurrence upper limit value as the upper limit value of the ink ejection amount at which the ink aggregation does not occur. The upper limit of occurrence, The non-occurrence upper limit value among the non-occurrence upper limit value as the upper limit value of the ink discharge amount, which is calculated based on the color measurement information obtained by the color measurement unit and does not cause color saturation of the ink. The upper limit value of the ink ejection amount is determined based on the upper limit value.
According to the printing apparatus of this aspect, the non-occurrence upper limit value as the upper limit value of the ink ejection amount that does not cause ink overflow and the ink bleeding calculated based on the imaging information obtained by the imaging unit. At least one non-occurrence upper limit value as an upper limit value of the non-occurrence ink discharge amount and an upper limit value of the non-occurrence as an upper limit value of the ink discharge amount at which ink aggregation does not occur, and colorimetry Ink based on at least one non-occurrence upper limit value among the non-occurrence upper limit value as the upper limit value of the ink discharge amount, which is calculated based on the colorimetric information obtained by the section and does not cause ink color saturation The upper limit value of the discharge amount is determined. Therefore, the printing apparatus can suppress the occurrence of at least one element (phenomenon) among ink overflow, ink bleeding, ink aggregation, and ink color saturation. Even if the relationship between ink bleeding, ink aggregation, and ink color saturation is not understood, an appropriate upper limit value of the ink discharge amount can be easily determined.

(2) The printing apparatus according to the above aspect further includes a control unit, and the control unit is calculated by comparing the imaging information with a first threshold value to determine whether or not the ink overflows. The non-occurrence of the ink that does not occur is calculated by comparing the imaging information and the second threshold value to determine whether or not the ink is smeared, by comparing the non-occurrence upper limit value that does not cause ink overflow, and the second threshold value. At least one of the upper limit value and the non-occurrence upper limit value at which the ink aggregation does not occur, which is calculated by comparing the imaging information with a third threshold value to determine whether or not the ink aggregation has occurred. The non-occurrence upper limit value that does not cause the ink color saturation is calculated by calculating the non-occurrence upper limit value and comparing the colorimetric information with a fourth threshold value to determine the presence or absence of color saturation of the ink. Calculating the first threshold , The second threshold, the third threshold value, and the fourth threshold value may be determined based on the result of the sensory evaluation using the test patterns printed on the test medium.
According to the printing apparatus of this aspect, the printer further includes a control unit, and the control unit compares the imaging information with the first threshold value and determines whether or not the ink has overflowed. A non-occurrence upper limit value that is calculated by comparing the imaging information and the second threshold value to determine whether ink bleeding is present, the non-occurrence upper limit value that does not cause ink bleeding, the imaging information, and the third value By comparing at least one non-occurrence upper limit value that does not cause ink aggregation calculated by comparing the threshold value with the presence or absence of ink aggregation, at least one non-occurrence upper limit value is calculated. By comparing each threshold value and determining whether or not ink color saturation is present, the non-occurrence upper limit value at which ink color saturation does not occur is calculated. Therefore, each non-occurrence upper limit value is accurately calculated using each threshold value. And the user can overflow Bleeding and, the coagulation of the ink, even if you do not understand the relationship between the ink color saturation can readily determine the upper limit of the proper ink ejection amount. Further, since the first threshold value, the second threshold value, the third threshold value, and the fourth threshold value are determined based on the result of sensory evaluation using the test pattern printed on the test medium, The threshold value can be determined based on the result of statistical analysis of the visual recognition result. As a result, each non-occurrence upper limit value calculated using the determined threshold value can be set to a value suitable for human senses.

(3) In the printing apparatus of the above aspect, the test pattern includes a first determination region for determining whether or not the ink overflows, whether or not the ink bleeds, and whether or not the ink aggregates; You may have at least 1 determination area | region among the 2nd determination area | region for determining the presence or absence of the color saturation of the said ink.
According to the printing apparatus of this aspect, the test pattern includes a first determination region for determining whether ink overflows, whether ink bleeds, and whether ink is aggregated, and whether ink color saturation occurs. Since it has at least one determination area among the second determination areas for determining the presence / absence of ink, the presence / absence of ink overflow, the presence / absence of ink bleeding, the presence / absence of ink aggregation, and the presence / absence of color saturation of ink Can be easily determined.

(4) In the printing apparatus according to the above aspect, the ejection amount upper limit determination unit may determine a non-occurrence upper limit value having the smallest value among the non-occurrence upper limit values as the upper limit value of the ink ejection amount. Good.
According to the printing apparatus of this aspect, the discharge amount upper limit determining unit determines the lowest occurrence non-occurrence upper limit value among the non-occurrence upper limit values as the upper limit value of the ink discharge amount. The occurrence of at least one element (phenomenon) of ink bleeding and ink aggregation and ink color saturation can be suppressed, and the ink discharge amount can be minimized.

(5) In the printing apparatus of the above aspect, the upper limit of the ink ejection amount with respect to at least one of the ink overflow, the ink bleeding, and the ink aggregation and the color saturation of the ink Priorities for determining the values may be set in advance, and the discharge amount upper limit determination unit may determine the upper limit of the ink discharge amount according to the priority.
According to the printing apparatus of this aspect, the priority for determining the upper limit value of the ink discharge amount is set in advance, and the discharge amount upper limit determination unit determines the upper limit of the ink discharge amount according to the priority. Since the value is determined, it is possible to suppress the occurrence of high-priority elements (phenomena) among ink overflow, ink bleeding, ink aggregation, and ink color saturation.

(6) In the printing apparatus according to the above aspect, the discharge amount of the ink may correspond to at least one of the overflow of the ink, the bleeding of the ink, and the aggregation of the ink, and the color saturation of the ink. You may further have a display part which displays the priority at the time of determining an upper limit.
According to the printing apparatus of this aspect, since the display unit displays the priority when determining the upper limit value of the ink ejection amount, the priority can be confirmed in the printing apparatus, and the convenience for the user can be improved.

(7) The printing apparatus according to the above aspect may further include a user interface for setting the priority.
According to the printing apparatus of this aspect, since the user interface for setting the priority is provided, the priority can be set in the printing apparatus, and the convenience for the user can be improved.

(8) In the printing apparatus of the above aspect, the user interface may include a radio button for setting the priority.
According to the printing apparatus of this aspect, the user interface has the radio button for setting the priority. Therefore, the operation load when setting the priority can be reduced, and the convenience for the user can be improved.

(9) In the printing apparatus of the above aspect, the user interface may include an input unit for inputting the priority as a priority.
According to the printing apparatus of this aspect, since the input unit for inputting the priority as the priority order is provided, the priority order desired by the user can be easily input, and the convenience for the user can be improved.

(10) The printing apparatus according to the above aspect may further include a storage unit that stores the imaging information and the colorimetric information.
According to the printing apparatus of this aspect, since the storage unit stores the imaging information and the colorimetric information, for example, the priority when determining the upper limit value of the ink ejection amount is changed and the ink ejection amount is again set. When it is desired to determine the upper limit value, the upper limit value of the ink discharge amount can be determined based on the previously acquired imaging information and colorimetric information, and the determination process of the upper limit value of the ink discharge amount can be executed in a short time. Alternatively, the load required for such processing can be reduced.

  The present invention can be realized in various forms. For example, the present invention can be realized in the form of a printing method, an ink discharge amount determination method, a computer program for realizing these methods, a recording medium on which such a computer program is recorded, and the like.

  A plurality of constituent elements of each aspect of the present invention described above are not indispensable, and some or all of the effects described in the present specification are to be solved to solve part or all of the above-described problems. In order to achieve the above, it is possible to appropriately change, delete, replace with another new component, and partially delete the limited contents of some of the plurality of components. In order to solve part or all of the above-described problems or to achieve part or all of the effects described in this specification, technical features included in one embodiment of the present invention described above. A part or all of the technical features included in the other aspects of the present invention described above may be combined to form an independent form of the present invention.

1 is a block diagram illustrating a configuration of a printing apparatus as an embodiment of the present invention. It is explanatory drawing which shows the structure of the nozzle row in a printing part. It is explanatory drawing which shows typically the test medium with which the solid test pattern was printed by the printing apparatus. It is explanatory drawing which shows typically the test medium with which the test pattern with a line was printed by the printing apparatus. It is explanatory drawing which shows the detailed structure of a test area | region typically. 6 is a flowchart illustrating a processing procedure of ink discharge amount upper limit determination processing. It is a flowchart which shows the process sequence of a printing process. It is a figure which shows the ink density | concentration when the overflow of an ink arises. 5 is an explanatory diagram for explaining the presence or absence of ink bleeding on the print medium P. FIG. 5 is an explanatory diagram for explaining the presence or absence of ink bleeding on the print medium P. FIG. 5 is an explanatory diagram for explaining the presence or absence of ink aggregation on the print medium P. FIG. 5 is an explanatory diagram for explaining the presence or absence of ink aggregation on the print medium P. FIG. FIG. 6 is an explanatory diagram schematically illustrating an example of an operation screen for determining an upper limit value of an ink discharge amount. FIG. 10 is an explanatory diagram schematically illustrating an example of an operation screen for determining an upper limit value of an ink ejection amount in Modification 1.

A. First embodiment:
A1. Overall configuration of the printing device:
FIG. 1 is a block diagram showing a configuration of a printing apparatus 200 as an embodiment of the present invention. The printing apparatus 200 discharges ink from a plurality of nozzles to the print medium P, thereby forming dots on the print medium P and printing an image or the like. The printing apparatus 200 is configured as an ink jet printer that ejects ink of four colors, C (cyan), M (magenta), Y (yellow), and K (black). The printing apparatus 200 is a pre-shipment printing apparatus, which prints a test pattern, which will be described later, on a printing medium P and uses the test medium on which the test pattern is printed, to determine the ink ejection amount in the printing apparatus 200. Determine the upper limit. The printing apparatus 200 includes a supply unit 210, a transport unit 220, a carriage movement unit 240, a carriage 230, a control unit 300, and a display unit 400.

  The printing apparatus 200 converts the image data received from the print control apparatus 100 into print data indicating on / off of dots on the print medium P, and based on the print data, the supply unit 210, the transport unit 220, and the carriage movement By controlling the unit 240 and the carriage 230 and ejecting ink onto the print medium P, dots are formed on the print medium P, and an image or the like is printed. In FIG. 1, the carriage 230 reciprocates along the main scanning direction X, and the print medium P is conveyed from upstream to downstream in the sub-scanning direction Y. The sub-scanning direction Y is a direction that intersects the main scanning direction X, and is a direction that is orthogonal to the main scanning direction X in the present embodiment.

  The print control apparatus 100 transmits image data of an image to be printed to the printing apparatus 200. The printing control apparatus 100 is configured to be able to communicate with the printing apparatus 200. In the present embodiment, the print control apparatus 100 is configured by a personal computer.

  The supply unit 210 supplies the print medium P to the transport unit 220 in response to a control signal from the control unit 300. The supply unit 210 includes a paper tray (not shown), and print media P are stacked and stored in the paper tray. In addition, it may replace with a paper tray and the structure provided with the roll body by which the printing medium P was wound, the roll drive motor, and the roll drive wheel train may be sufficient.

  The transport unit 220 drives the transport roller 221 in accordance with a control signal from the control unit 300, thereby moving the print medium P supplied by the supply unit 210 relative to the carriage movement unit 240. Although not shown, the transport unit 220 is provided with sensors such as a feed detection sensor that detects the transport amount of the print medium P and a front end detection sensor that detects the front end position of the print medium P. The control unit 300 refers to signals from these sensors and controls the transport unit 220.

  The carriage moving unit 240 reciprocates the carriage 230 along the main scanning direction X in response to a control signal from the control unit 300. The carriage moving unit 240 includes a carriage guide shaft 241 and a carriage motor (not shown). The carriage guide shaft 241 is disposed along the main scanning direction X, and both ends are fixed to the casing of the printing apparatus 200. The carriage 230 is attached to the carriage guide shaft 241 so as to reciprocate in the main scanning direction X. When the carriage moving unit 240 drives the carriage motor in response to a control signal from the control unit 300, the carriage 230 reciprocates along the carriage guide shaft 241. Although not shown, the carriage moving unit 240 includes a carriage position sensor that detects the position of the carriage 230. The control unit 300 refers to the signal from the carriage position sensor and controls the movement amount of the carriage 230.

  The carriage 230 includes a printing unit 231, an imaging unit 232, and a color measurement unit 233. The printing unit 231 prints an image by ejecting ink droplets onto the printing medium P in accordance with a control signal from the control unit 300. A plurality of nozzles that eject ink are provided on the surface of the printing unit 231 that faces the print medium P. Details of the configuration of the printing unit 231 will be described later.

  The imaging unit 232 captures an image printed on the print medium P, that is, a dot group formed on the print medium P. The imaging unit 232 is disposed on the surface of the carriage 230 that faces the print medium P, and captures an image when the carriage 230 moves in the main scanning direction X. As illustrated in FIG. 1, the imaging unit 232 is disposed on the downstream side of the printing unit 231 in the sub-scanning direction Y in the carriage 230. Thereby, it is possible to capture an image when the print medium P is transported downstream by the transport unit 220. Information obtained by imaging is stored in the memory 330 as imaging information 333. In the present embodiment, the imaging unit 232 is configured by an area sensor. Note that a line sensor may be used instead of the area sensor.

  The color measuring unit 233 measures colors of each component (L * value, a * value, b * value) in the coordinates in the color space of the dot group formed on the print medium P. The L * value is lightness and represents darkness due to ink density. The a * value and the b * value are chromaticity and represent the color name and the degree of vividness. As shown in FIG. 1, the color measurement unit 233 is disposed on the surface of the carriage 230 that faces the print medium P, similarly to the imaging unit 232, and performs color measurement when the carriage 230 moves in the main scanning direction X. To do. In addition, since the color measurement unit 233 is disposed on the downstream side of the printing unit 231 in the sub-scanning direction Y in the carriage 230, color measurement can be performed when the print medium P is conveyed downstream by the conveyance unit 220. In the present embodiment, the color measurement unit 233 is configured by a spectroscopic sensor. The color measuring unit 233 measures the spectral reflectance of the dot group formed on the print medium P and derives information on the color density. The measurement result is stored in the memory 330 as colorimetric information 334. The color density is an index (density) indicating the color density measured for each color component of the color reproduced by the dot group of the print medium P, and is synonymous with the ink density except for black ink. It is.

  The control unit 300 includes an input / output interface 310, a memory 330, a unit control circuit 340, and a CPU 320.

  The input / output interface 310 outputs image data input from the print control apparatus 100 to the CPU 320.

  The memory 330 stores a control program for controlling the operation of the printing apparatus 200, solid pattern data 331, and line pattern data 332. Further, as described above, the imaging information 333 and the colorimetric information 334 are stored in the memory 330. In the present embodiment, the memory 330 corresponds to a storage unit in a means for solving the problem.

  The solid pattern data 331 is image data of a solid test pattern 631 described later. The line pattern data 332 is image data of a line test pattern 632 described later. The detailed configuration of each test pattern will be described later.

  The unit control circuit 340 includes control circuits that respectively control the supply unit 210, the transport unit 220, and the carriage movement unit 240 described above, and controls the operation of each unit according to a control signal from the CPU 320.

  The CPU 320 functions as the control unit 321 by expanding and executing the control program stored in the memory 330. The control unit 321 controls each unit of the printing apparatus 200, and also overflows an upper limit calculation unit 322, a blur upper limit calculation unit 323, an aggregation upper limit calculation unit 324, a color saturation upper limit calculation unit 325, and an ejection. It functions as the amount upper limit determination unit 326.

  The control unit 321 controls the conversion processing of image data into print data, the main scanning operation of the carriage 230, the transport operation of the print medium P, and the ink discharge operation from each nozzle. Specifically, the control unit 321 converts the resolution of the image data into a print resolution, and converts the image data into image data represented by ink color C, M, Y, and K tone values. Then, the image data of each ink color is converted into the gradation value of two gradations, that is, the presence / absence of dots of each ink color, in other words, the presence of dots (255) and the absence of dots (0). The control unit 321 rasterizes data indicating the presence / absence of dots on the print media P of the ink colors C, M, Y, and K, and generates print data including a print control command.

  When the generation of the print data is completed, the control unit 321 drives the carriage motor of the carriage moving unit 240 by transmitting a control signal to the unit control circuit 340 in order to control the main scanning operation of the carriage 230, 230 is moved to the printing start position in the main scanning direction X. Further, the control unit 321 supplies the print medium P from the supply unit 210 to the transport unit 220 by transmitting a control signal to the unit control circuit 340 in order to control the transport operation of the print medium P. In addition, by transmitting a control signal to the unit control circuit 340, the transport motor of the transport unit 220 is driven to transport the print medium P to the print start position in the sub-scanning direction Y.

  The control unit 321 generates a control signal for driving the printing unit 231 based on the print data, and transmits the control signal to the printing unit 231 via the unit control circuit 340. The unit control circuit 340 controls the carriage moving unit 240 according to a control signal from the control unit 321, so that printing is performed by the printing unit 231. More specifically, the dot formation processing of the print medium P by the printing unit 231 according to the control signal from the control unit 321 and the sub-scanning direction of the print medium P by the transport unit 220 according to the control signal from the control unit 321 An image is printed on the print medium P by executing the conveyance process to Y and the movement process of the carriage 230 in the main scanning direction X by the carriage movement unit 240 according to the control signal from the control unit 321. .

  The overflow upper limit calculation unit 322 calculates an upper limit value of an ink discharge amount that does not cause ink overflow (hereinafter referred to as an “overflow non-occurrence upper limit value”) in an ink discharge amount upper limit determination process described later. In the present embodiment, the “upper limit value of ink ejection amount” means the upper limit value of the total amount of ink that can be ejected in a unit area of the print medium P. Also, “ink overflow” is a phenomenon in which ink accumulates in the periphery of the ink droplet during the ink drying process, and the ink concentration in the peripheral portion of the ink droplet becomes higher than the ink concentration in the central portion of the ink droplet. Means. A method for determining the presence or absence of ink overflow will be described later.

  The bleeding upper limit value calculation unit 323 calculates an upper limit value of an ink ejection amount that does not cause ink bleeding (hereinafter, referred to as “a bleeding-free upper limit value”) in an ink ejection amount upper limit determination process described later. In the present embodiment, “ink bleeding” means a phenomenon in which the ink ejected onto the print medium P is not absorbed by the print medium P and an ink pool is formed in the contour portion of the ink droplets, resulting in rattling. To do. A method for determining the presence or absence of ink bleeding will be described later.

  The aggregation upper limit calculation unit 324 calculates an upper limit value of the ink ejection amount (hereinafter referred to as “aggregation non-occurrence upper limit value”) at which ink aggregation does not occur in an ink ejection amount upper limit determination process described later. In the present embodiment, “ink aggregation” means a phenomenon in which the granularity, that is, the dispersibility of dots formed on the print medium P is reduced. A method for determining the presence or absence of ink aggregation will be described later.

  The color saturation upper limit calculation unit 325 calculates an upper limit value of an ink discharge amount that does not cause ink color saturation (hereinafter referred to as “color saturation non-occurrence upper limit value”) in an ink discharge amount upper limit determination process described later. . In the present embodiment, “ink color saturation” means a state in which the amount of change in ink density with respect to the ink amount does not increase, in other words, a state in which the ink concentration does not increase even if the ink amount increases. A method for determining the presence or absence of ink color saturation will be described later.

  The discharge amount upper limit determination unit 326 determines an upper limit value of the ink discharge amount in an ink discharge amount upper limit determination process described later. The upper limit value of the ink ejection amount is used, for example, when creating a color conversion table used in print processing described later. In the present embodiment, the upper limit value of the ink ejection amount is determined as the upper limit value of the ink duty of each ink color. “Ink duty” is the ratio of the discharge amount to the maximum discharge amount of ink, and means the dot recording rate per unit area on the print medium P.

  In the present embodiment, the discharge amount upper limit determination unit 326 determines the upper limit value of the ink discharge amount based on each non-occurrence upper limit value determined for each avoidance target element. The avoidance target element is an element that should be avoided in printing and should be considered when determining the upper limit value of the ink discharge amount. In this embodiment, the avoidance target element corresponds to ink overflow, ink bleeding, ink aggregation, and ink color saturation. A detailed description of the ink discharge amount upper limit determination process will be described later.

  The display unit 400 is used for performing various operations related to the printing apparatus 200. The display unit 400 includes a large liquid crystal screen, and displays a menu screen when using various functions of the printing apparatus 200 and an information screen for notifying the user of malfunctions and errors. The printing apparatus 200 is controlled based on a user instruction input to the display unit 400. On the above-described menu screen, for example, an operation screen for an ink discharge amount upper limit determination process described later is displayed. A detailed description of the operation screen will be described later.

A2. Schematic configuration of printing section:
FIG. 2 is an explanatory diagram illustrating a configuration of the nozzle row 70 in the printing unit 231. FIG. 2 shows a surface of the printing unit 231 that faces the print medium P. The printing unit 231 includes a nozzle row 70 that ejects each ink. The nozzle row 70 includes a nozzle row 70C that discharges cyan (C) ink, a nozzle row 70M that discharges magenta (M) ink, a nozzle row 70Y that discharges yellow (Y) ink, and black (K) ink. And a nozzle row 70K for discharging. These four nozzle rows 70C, 70M, 70Y and 70K are arranged at predetermined intervals along the main scanning direction X. Each of the nozzle rows 70C, 70M, 70Y and 70K is composed of a plurality of nozzles 71 arranged at a predetermined interval along the sub-scanning direction Y. The number of nozzles along the sub-scanning direction Y of each nozzle row 70C, 70M, 70Y, and 70K is equal. Accordingly, the nozzle heights Nh of the nozzle rows 70C, 70M, 70Y and 70K are equal to each other.

  Each nozzle 71 is provided with an ink chamber and a piezo element (not shown), and ink droplets are ejected from each nozzle 71 as the ink chamber expands and contracts by driving the piezo element.

A3. Schematic configuration of test medium:
FIG. 3 is an explanatory diagram schematically showing a test medium 600 on which a solid test pattern 631 is printed by the printing apparatus 200. The test medium 600 is used to determine the presence or absence of ink color saturation when determining the upper limit value of the ink ejection amount in the printing apparatus 200. The test medium 600 has a configuration in which a solid test pattern 631 is printed on the print medium P. The solid test pattern 631 has solid pattern rows BP1, BP2, BP3, BP4, and BP5 at predetermined intervals along the main scanning direction X. Each of the solid pattern rows BP1 to BP5 has substantially rectangular test areas 501 to 505 (also referred to as patches) at predetermined intervals along the sub-scanning direction Y. In FIG. 3, only the test areas 501 to 505 of the solid pattern row BP1 are denoted by reference numerals, but the solid pattern rows BP2 to BP5 also have similar test areas 501 to 505. Each of the test areas 501 to 505 has the same configuration except for the print density. In the present embodiment, solid images are printed in the test areas 501 to 505. The print density is an index (density) indicating the print density reproduced by the dot group of the print medium P.

  The solid test pattern 631 is printed with different ink colors for the solid pattern rows BP1 to BP5. Specifically, each test region 501 to 505 of the solid pattern row BP1 is printed by the nozzle row 70C ejecting cyan ink. Each test area 501 to 505 of the solid pattern row BP2 is printed by ejecting magenta ink by the nozzle row 70M. Each test area 501 to 505 of the solid pattern row BP3 is printed by the nozzle row 70Y ejecting yellow ink. The test areas 501 to 505 of the solid pattern row BP4 are printed by the nozzle row 70K ejecting black ink. The test areas 501 to 505 of the solid pattern row BP5 are printed by the nozzle row 70C ejecting cyan ink and the nozzle row 70M ejecting magenta ink, respectively.

  As shown in FIG. 3, each of the test areas 501 to 505 is printed so that the print density is changed from a dark state to a light state as it goes from the upstream side to the downstream side in the sub-scanning direction Y. In other words, printing is performed such that the ink duty decreases from the upstream side to the downstream side in the sub-scanning direction Y. Specifically, the test area 501 is printed so that the ink duty is 100%. The test area 502 is printed so that the ink duty is 90%. The test area 503 is printed so that the ink duty is 80%. The test area 504 is printed so that the ink duty is 70%. The test area 505 is printed so that the ink duty is 60%.

  The test area 501 has a color saturation determination area SCAr. The color saturation determination area SCAr is an area corresponding to substantially the entire test area 501. The color saturation determination area SCAr is used for determining whether or not there is color saturation.

  Since each of the test areas 501 to 505 has the same configuration except for the print density, each of the test areas 502 to 505 also has the above-described color saturation determination area SCAr like the test area 501. In the present embodiment, the color saturation determination area SCAr corresponds to the second determination area in the means for solving the problem.

  FIG. 4 is an explanatory diagram schematically showing a test medium 601 on which a test pattern 632 with lines is printed by the printing apparatus 200. The test medium 601 is used to determine whether there is ink overflow, ink bleeding, and ink aggregation when determining the upper limit value of the ink ejection amount in the printing apparatus 200. It is done. The test medium 601 has the same configuration as the test medium 600 shown in FIG. 3 except for the configuration of each test area.

  Specifically, as shown in FIG. 4, the test medium 601 has a configuration in which a test pattern 632 with lines is printed on the print medium P. The test pattern 632 with lines has line pattern rows LP1, LP2, LP3, LP4, and LP5 at predetermined intervals along the main scanning direction X. Each line pattern row LP1 to LP5 has substantially rectangular test regions 511 to 515 at predetermined intervals along the sub-scanning direction Y. In FIG. 4, only the test areas 511 to 515 of the line pattern row LP1 are denoted by reference numerals, but the line pattern rows LP2 to LP5 also have similar test areas 511 to 515. Each of the test areas 511 to 515 has the same configuration except for the print density. In the present embodiment, each of the test areas 511 to 515 is divided into six areas, and a solid image is printed in each area. The detailed configuration of each of the test areas 511 to 515 will be described later.

  The test pattern 632 with lines is printed with a different ink color for each of the line pattern rows LP1 to LP5. In addition, each of the six regions in each of the line pattern rows LP1 to LP5 is printed with a different ink color for each adjacent region. Specifically, in the line pattern row LP1, among the six regions in the test regions 511 to 515, the upper left region is printed by the nozzle row 70C ejecting cyan ink. In the right adjacent area, the nozzle row 70K is black ink, in the central left area, the nozzle row 70K is black ink, in the right adjacent area, the nozzle row 70C is cyan ink, and in the lower left area, the nozzle row 70C is cyan. Ink is printed in the area adjacent to the right by ejecting black ink from the nozzle row 70K.

  In each of the test areas 511 to 515 of the line pattern array LP2, areas corresponding to areas printed by discharging cyan ink in the line pattern array LP1 are printed by the nozzle array 70M discharging magenta ink. .

  In each of the test areas 511 to 515 of the line pattern row LP3, an area corresponding to the area printed by ejecting cyan ink in the line pattern row LP1 is printed by the nozzle row 70Y ejecting yellow ink. .

  In each test region 511 to 515 of the line pattern row LP4, the region corresponding to the region printed by discharging cyan ink in the line pattern row LP1 is the nozzle row 70M ejecting magenta ink and the nozzle row 70Y is yellow. Printing is performed by ejecting ink. In the line pattern row LP1, a region corresponding to a region printed by discharging black ink is printed by the nozzle row 70C discharging cyan ink and the nozzle row 70M discharging magenta ink.

  In each of the test areas 511 to 515 of the line pattern line LP5, the area corresponding to the area printed by ejecting cyan ink in the line pattern line LP1 is such that the nozzle line 70C ejects cyan ink and the nozzle line 70Y is yellow. Printing is performed by ejecting ink. In the line pattern row LP1, a region corresponding to a region printed by discharging black ink is printed by the nozzle row 70M discharging magenta ink and the nozzle row 70Y discharging yellow ink.

  The test areas 511 to 515 are printed so that the ink duty decreases from the upstream side to the downstream side in the sub-scanning direction Y, similarly to the test areas 501 to 505 shown in FIG. Specifically, as shown in FIG. 4, the test area 511 is printed so that the ink duty is 100%. The test area 512 is printed so that the ink duty is 90%. The test area 513 is printed so that the ink duty is 80%. The test area 514 is printed so that the ink duty is 70%. The test area 515 is printed so that the ink duty is 60%.

A4. Detailed configuration of test area in test pattern with lines:
FIG. 5 is an explanatory diagram schematically showing the detailed configuration of the test area 511. As described above, each of the test areas 511 to 515 in the test pattern with line 632 has the same configuration except for the print density. Therefore, the detailed configuration of the test area 511 will be described as a representative. As shown in FIG. 5, the test region 511 has four solid regions MCAr1, MCAr2, MCAr3, and MCAr4, and two line segment regions LCAr1 and LCAr2.

  The four solid regions MCAr1, MCAr2, MCAr3, and MCAr4 are arranged at four corners in the test region 511. Each of the solid regions MCAr1 to MCAr4 has a substantially rectangular shape. Each of the solid regions MCAr1 to MCAr4 is used for determining whether ink overflows or whether ink is aggregated in an ink discharge amount upper limit determination process described later.

  The line segment region LCAr1 is disposed so as to be sandwiched between the solid region MCAr1 on the upstream side in the sub-scanning direction Y and the solid region MCAr2 on the downstream side in the sub-scanning direction Y. The line segment region LCAr2 is disposed so as to be sandwiched between the solid region MCAr4 on the upstream side in the sub-scanning direction Y and the solid region MCAr3 on the downstream side in the sub-scanning direction Y. Each line segment region LCAr1 and LCAr2 has a substantially rectangular shape. Each of the line segment regions LCAr1 and LCAr2 is used for determining whether or not there is ink bleeding in an ink discharge amount upper limit determination process described later. In the present embodiment, the solid areas MCAr1 to MCAr4 and the line segment areas LCAr1 and LCAr2 correspond to a first determination area in the means for solving the problem.

A5. Ink discharge amount upper limit determination processing:
FIG. 6 is a flowchart showing the processing procedure of the ink discharge amount upper limit determination process. The ink discharge amount upper limit determination process is executed when the manufacturer of the printing apparatus 200 selects an operation menu for executing the ink discharge amount upper limit determination process on the display unit 400. As shown in FIG. 6, the control unit 321 prints a solid test pattern 631 (step S100).

  FIG. 7 is a flowchart illustrating the processing procedure of the printing process. As illustrated in FIG. 7, the control unit 321 performs resolution conversion processing on the processing target image data (step S <b> 200). In step S <b> 100 shown in FIG. 6, the image data to be processed is solid pattern data 331. In this embodiment, the solid pattern data 331 and the line pattern data 332 are image data having gradation values (0 to 255) composed of red (R), green (G), and blue (B) color components. It is. In step S <b> 200 shown in FIG. 7, the control unit 321 converts the resolution of the image data into a resolution for printing on the print medium P.

  The control unit 321 executes color conversion processing (step S205). Specifically, the control unit 321 refers to a color conversion table (not shown) and converts the RGB data into CMYK data of 256 gradations represented by the color space of the ink color CMYK of the printing apparatus 200.

  The control unit 321 executes halftone processing (step S210). Specifically, the control unit 321 refers to a dither mask (not shown), and has four gradation values (2 bits) that can be expressed by the printing apparatus 200 with 256 gradation values (stages) of CMYK data. Data).

  The control unit 321 executes print data output processing using the image data after the halftone processing (step S215). Specifically, the control unit 321 executes rasterization processing based on the image data after halftone processing, and generates print data.

  When the generation of the print data is completed, the control unit 321 controls the carriage 230 and the transport unit 220 to execute printing (step S220). Specifically, a plurality of scans of the carriage 230 and ejection of ink onto the print medium P and conveyance of the print medium P to the downstream side in the sub-scanning direction Y are alternately repeated to form dots on the print medium P. Form. When step S220 is completed, step S100 shown in FIG. 6 is completed.

  After step S100 is completed, the control unit 321 controls the printing apparatus 200 to pull back the print medium P on which the solid test pattern 631 is printed, that is, the test medium 600 to the upstream side in the sub-scanning direction Y. At this time, the test medium 600 is transported to the upstream side in the sub-scanning direction Y by driving the transport motor of the transport unit 220 in the reverse direction from that during printing.

  The color measuring unit 233 measures the color of the test medium 600 on which the solid test pattern 631 is printed (step S105). Specifically, the solid test pattern 631 is measured when the carriage 230 moves in the main scanning direction X while the test medium 600 is conveyed downstream in the sub-scanning direction Y. Information obtained by color measurement is stored in the memory 330 as color measurement information 334.

  The control unit 321 prints the test pattern 632 with a line (step S110). In step S110, similarly to step S100 described above, the printing process shown in FIG. 7 is executed. Image data to be processed in the printing process in step S110 shown in FIG. After the completion of step S110, similarly to the completion of step S100 described above, the control unit 321 controls the printing apparatus 200 to print the print medium P on which the lined test pattern 632 is printed, that is, the test medium 601. It is pulled back to the upstream side in the scanning direction Y.

  The imaging unit 232 images the test medium 601 on which the test pattern 632 with lines is printed (step S115). Specifically, a test pattern 632 with a line is imaged when the carriage 230 moves in the main scanning direction X while the test medium 601 is conveyed downstream in the sub-scanning direction Y. Information obtained by imaging is stored in the memory 330 as imaging information 333.

  The overflow upper limit calculation unit 322, the bleeding upper limit calculation unit 323, and the aggregation upper limit calculation unit 324 are based on the imaging information 333, and do not cause ink overflow, ink bleeding, and ink aggregation. The generation upper limit value is calculated (step S120). Specifically, the overflow upper limit calculation unit 322 calculates an overflow non-occurrence upper limit value by determining the presence or absence of ink overflow in each of the test areas 511 to 515 from the imaging information 333. The bleeding upper limit value calculation unit 323 calculates the bleeding non-occurrence upper limit value by determining the presence or absence of ink bleeding in each of the test areas 511 to 515 from the imaging information 333. The aggregation upper limit value calculation unit 324 calculates an aggregation non-occurrence upper limit value by determining the presence or absence of ink aggregation in each of the test areas 511 to 515 from the imaging information 333. A detailed description of a method for determining whether or not each avoidance target element has occurred will be described later.

  Based on the colorimetric information 334, the color saturation upper limit calculation unit 325 calculates a non-occurrence upper limit that does not cause color saturation of ink (step S125). Specifically, the color saturation upper limit calculation unit 325 calculates the color saturation non-occurrence upper limit by determining the presence or absence of ink color saturation in each of the test areas 501 to 505 from the colorimetric information 334. A detailed description of a method for determining whether or not ink color saturation has occurred will be described later.

  The discharge amount upper limit determination unit 326 determines the upper limit value of the ink discharge amount based on each non-occurrence upper limit value (step S130). Specifically, among the non-occurrence upper limit values calculated in step S120 and step S125, the non-occurrence upper limit value having the smallest value is determined as the upper limit value of the ink ejection amount. The determined upper limit value of the ink ejection amount is stored in the memory 330 and used to create the color conversion table described above.

A6. Judgment of occurrence of each avoidance target element:
In the above-described ink discharge amount upper limit determination process, the presence or absence of each avoidance target element is determined as follows. The presence / absence of ink overflow is determined based on the difference in ink density fluctuation in the vicinity of the boundary between the ink ejection portion (printed portion) and the ink non-ejection portion (non-printed portion). Specifically, like the so-called coffee stain phenomenon, the ink ejected to each of the test areas 511 to 515 shown in FIG. 4 gathers around the test areas 511 to 515 in the course of drying the ink, Overflow can occur. FIG. 8 is a diagram illustrating the ink density in each of the test areas 511 to 515 when ink overflow occurs. As shown in FIG. 8, when the ink overflows, the ink density in the peripheral part becomes higher than the ink density in the central part. Therefore, the presence or absence of ink overflow is determined based on the imaging information 333 by the difference between the ink density at the peripheral part (for example, point A in FIG. 8) and the ink density at the central part (for example, point B in FIG. 8). Is compared with a predetermined threshold value (first threshold value). That is, when the difference between the ink density in the peripheral part and the ink density in the central part is a value equal to or greater than the first threshold value, it is determined that there is ink overflow. On the other hand, when the difference between the ink density in the peripheral part and the ink density in the central part is smaller than the first threshold value, it is determined that there is no ink overflow.

  The first threshold value used for determining whether or not ink overflows is determined in advance by a plurality of testers (person who performs sensory evaluation) sensory-evaluating a plurality of test patterns printed on the print medium P. That is, as shown in FIG. 8, a plurality of types of test patterns having a difference in ink density between the peripheral portion and the central portion are prepared corresponding to the difference in ink concentration and printed on the print medium P. The tester performs a sensory evaluation by visually recognizing a plurality of types of test patterns printed on the print medium P and selecting a test pattern that can visually recognize the difference in ink density. The first threshold value is determined by statistically analyzing the result of performing the same sensory evaluation on a plurality of testers. For example, in finally determining the first threshold value from the analysis result, a histogram having a difference in ink density as a bin may be created, and the difference in ink density at the peak frequency may be set as the first threshold value. The average value may be the first threshold value. The first threshold value may be determined as a design specification based on the required performance of the printing apparatus 200 according to the present invention with reference to the histogram. As described above, since the first threshold value is determined based on the result of statistical analysis of the visual recognition results of many people (testers), the presence or absence of ink overflow is determined using the first threshold value. As a result, a result suitable for human senses can be obtained. The first threshold value determined as described above is stored in advance in the control unit 321 or the memory 330 (storage unit).

  9A and 9B are explanatory diagrams for explaining the presence or absence of ink bleeding on the print medium P. FIG. FIG. 9A shows a state without ink bleeding, and FIG. 9B shows a state with magenta ink bleeding. 9A and 9B schematically show a state in which print data different from the pattern data 331 and 332 of the present embodiment is printed in order to easily understand ink bleeding. As shown in FIG. 9A, a line segment LC and a line segment LM are printed on the print medium P. The line segment LC is printed by ejecting cyan ink from the nozzle row 70C. The line segment LM is printed by ejecting magenta ink from the nozzle row 70M. The width w1 of the line segment LC and the width w1 of the line segment LM are equal to each other when there is no ink bleeding on the print medium P as shown in FIG. 9A.

  As shown in FIG. 9B, the line segment LC and the line segment LM are printed on the print medium P, as in FIG. 9A. The line segment LM shown in FIG. 9B is printed so that the ink duty becomes excessively larger than the line segment LM shown in FIG. 9A. For this reason, the magenta ink is blurred at the boundary between the print medium P and the line segment LM, and rattling occurs. At this time, the width (average width) of the line segment LM is a width w2 larger than the width w1 of the line segment LC. Further, at the boundary between the line segment LC and the line segment LM, magenta ink is blotted and eroded into the line segment LC, and rattling occurs.

  As can be understood by comparing FIG. 9A and FIG. 9B, the presence or absence of ink bleeding and the presence or absence of rattling on the print medium P is determined by the width of the line segment LC printed on the print medium P and the line segment LM. This can be determined by paying attention to the difference from the width of the. In the above-described ink discharge amount upper limit determination process, the line segments adjacent to each other are not compared with each other, but based on the imaging information 333 of the test pattern 632 with lines, the widths of the line segment regions LCAr1 and LCAr2; The difference between the widths of the line segment areas LCAr1 and LCAr2 when there is no ink bleeding is determined by comparing with a predetermined threshold value (second threshold value). That is, when the difference is a value equal to or larger than the second threshold value, it is determined that there is ink bleeding. On the other hand, when the difference is smaller than the second threshold, it is determined that there is no ink bleeding. In the present embodiment, the “width of the line segment region” means a length (length in the short direction) in a direction orthogonal to the length direction (longitudinal direction) of the line segment region.

  The second threshold value used for the determination of the presence or absence of ink bleeding is determined in advance by sensory evaluation of a plurality of test patterns printed on the print medium P by a plurality of testers. That is, a plurality of types of test patterns with ink bleeding as shown in FIG. 9B are prepared and printed on the print medium P according to the degree of ink bleeding. The tester performs sensory evaluation by visually recognizing a plurality of types of test patterns printed on the print medium P and selecting test patterns that can visually recognize the occurrence of ink bleeding. The second threshold value is determined by statistically analyzing the result of performing the same sensory evaluation on a plurality of testers. At this time, the statistical analysis and the determination of the second threshold value can be performed by the same method as the determination of the first threshold value described above. The determined second threshold value is stored in advance in the control unit 321 or the memory 330 (storage unit). Note that the widths of the line segment areas LCAr1 and LCAr2 when there is no ink bleeding are obtained in advance by experiments and stored in the control unit 321 or the memory 330 (storage unit).

  10A and 10B are explanatory diagrams for explaining the presence or absence of ink aggregation on the print medium P. FIG. FIG. 10A shows a state without ink aggregation, and FIG. 10B shows a state with ink aggregation. As shown in FIG. 10A, dots 101 to 113 are dispersed and formed on the print medium P by ink droplets ejected from the printing unit 231. On the other hand, before the ejected ink droplets are fixed, a plurality of adjacent inks may be attracted and gathered, and ink aggregation may occur. For example, in FIG. 10A, the dots 103 to 105 and the dot 107, the dot 108 and the dot 109 and the dot 112, the dot 110, the dot 111, and the dot 113 are gathered together to obtain the state of FIG. 10B. Ink agglomeration is likely to occur when there is a large amount of ejected ink or when the print medium P is a medium with low ink absorbability.

  When ink aggregation occurs, as can be seen from FIG. 10B, the dispersibility of the dots decreases, the dot size increases, and the distance between the dots increases. For example, the dot 105 ′ in FIG. 10B is formed by aggregating the dot 103, the dot 104, and the dot 107 on the dot 105 in FIG. 10A. Comparing the distance d1 (FIG. 10A) between the dot 105 and the nearest dot 104 and the distance d2 (FIG. 10B) between the dot 105 ′ and the nearest dot 102, the distance d1 <the distance d2, and the dot 105 Size <size of dot 105 ′. For this reason, the color of the portion where the ink is aggregated becomes dark, and is visually recognized as color unevenness. Therefore, the presence / absence of ink aggregation is based on the imaging information 333 based on at least one of the difference between the distance d2 and the distance d1 and the difference between the size of the dot 105 ′ and the size of the dot 105 based on a predetermined threshold (third It can be determined by comparing with (threshold). For example, when the difference between the distance d2 and the distance d1 is a value equal to or larger than the third threshold value, it is determined that the ink is aggregated. On the other hand, when the difference between the distance d2 and the distance d1 is smaller than the third threshold value, it is determined that there is no ink aggregation. Similarly, when the difference between the size of the dot 105 ′ and the size of the dot 105 is a value equal to or larger than the third threshold value, it is determined that there is ink aggregation. On the other hand, when the difference between the size of the dot 105 ′ and the size of the dot 105 is smaller than the third threshold value, it is determined that there is no ink aggregation. Of course, the third threshold value for determining the presence / absence of ink aggregation based on the distance between dots is different from the third threshold value for determining the presence / absence of ink aggregation based on the size of the dot. Yes, the third threshold value is appropriately determined according to the comparison object (distance between dots, dot size). Further, the presence / absence of ink aggregation may be determined from both the distance between dots and the size of the dot. In this case, binary values corresponding to both comparison objects are determined as the third threshold value.

  A dot 109 ′ shown in FIG. 10B is formed by agglomerating the dots 112 and 108 shown in FIG. 10A. Further, the dots 111 ′ shown in FIG. 10B are formed by agglomerating the dots 110 and 113 shown in FIG. 10A. Therefore, as shown in FIG. 10B, the color of the portion where the dots 109 ′ and 111 ′ are formed becomes dark and is recognized as color unevenness. As for the dot 109 ′ and the dot 111 ′, at least one of the distance between the dots and the size of the dot is set to the third value based on the imaging information 333 as in the case of the dot 105 ′. By comparing with the threshold value, the presence or absence of ink aggregation can be determined.

  The third threshold value used for determining the presence / absence of ink aggregation is determined in advance by sensory evaluation of a plurality of test patterns printed on the print medium P by a plurality of testers. That is, a plurality of types of test patterns in which ink aggregation occurs as shown in FIG. 10B is prepared and printed on the print medium P in accordance with the degree of ink aggregation. The tester performs sensory evaluation by visually recognizing a plurality of types of test patterns printed on the printing medium P and selecting a test pattern that can visually recognize the occurrence of ink aggregation (for example, occurrence of color unevenness). A third threshold value is determined by statistically analyzing the result of performing the same sensory evaluation on a plurality of testers. At this time, the statistical analysis and the determination of the third threshold value can be performed by the same method as the determination of the first threshold value described above. The determined third threshold value is stored in advance in the control unit 321 or the memory 330 (storage unit).

  The presence / absence of ink color saturation is determined from the locus of change in color density with respect to the ink amount. Specifically, the presence or absence of ink color saturation is calculated based on the colorimetric information 334 based on the degree of change in color density when the amount of ink is increased and printed on the print medium P. It is determined by comparing with a threshold value (fourth threshold value). That is, when the degree is a value equal to or smaller than the fourth threshold value, it is determined that there is ink color saturation. On the other hand, when the degree is larger than the fourth threshold, it is determined that there is no color saturation of the ink.

  The fourth threshold value used for determining the presence or absence of ink color saturation is determined in advance by sensory evaluation of a plurality of test patterns printed on the print medium P by a plurality of testers. That is, test areas (test patterns) 501 to 505 as shown in FIG. 3 are printed on the print medium P. The tester performs a sensory evaluation by visually recognizing a plurality of types of test patterns printed on the print medium P and selecting adjacent test patterns that can visually recognize the occurrence of ink color saturation. The fourth threshold value is determined by statistically analyzing the result of performing the same sensory evaluation on a plurality of testers. At this time, the statistical analysis and the determination of the fourth threshold value can be performed by the same method as the determination of the first threshold value described above. The determined fourth threshold value is stored in advance in the control unit 321 or the memory 330 (storage unit).

  According to the printing apparatus 200 of the first embodiment having the above configuration, based on the imaging information 333 and the colorimetric information 334, ink overflow, ink bleeding, ink aggregation, and ink color. A non-occurrence upper limit value that is an upper limit value of the ink ejection amount at which saturation does not occur is calculated. The discharge amount upper limit determination unit 326 determines an upper limit value of the ink discharge amount based on at least one non-occurrence upper limit value among the respective non-occurrence upper limit values. For this reason, it is possible to suppress the occurrence of at least one element (phenomenon) among ink overflow, ink bleeding, ink aggregation, and ink color saturation. Ink overflow, ink bleeding, and ink Even when the relationship between the aggregation of the ink and the color saturation of the ink is not understood, an appropriate upper limit value of the ink discharge amount can be easily determined.

  The test pattern 632 with lines has a first determination region for determining whether ink overflows, whether ink bleeds, and whether ink is aggregated. The solid test pattern 631 is a color of ink. Since the second determination area for determining the presence or absence of saturation is provided, the presence or absence of ink overflow, the presence or absence of ink bleeding, the presence or absence of ink aggregation, and the presence or absence of ink color saturation can be easily determined.

  Furthermore, since the discharge amount upper limit determination unit 326 determines the lowest occurrence non-occurrence upper limit value among the non-occurrence upper limit values as the upper limit value of the ink discharge amount, the ink overflow, the ink bleeding, the ink Occurrence of any element (phenomenon) among the aggregation of ink and the color saturation of ink can be suppressed.

B. Second embodiment:
In the first embodiment, among the non-occurrence upper limit values calculated for each avoidance target element, the lowest non-occurrence upper limit value is determined as the upper limit value of the ink ejection amount. However, the present invention is not limited to this. Not. For example, priorities may be set in advance for each avoidance target element, and the non-occurrence upper limit value calculated for the avoidance target element having the highest priority may be determined as the upper limit value of the ink ejection amount. In this configuration, specifically, a user interface (setting screen) for setting the priority of the avoidance target element is displayed on the display unit 400, and each avoidance target element is operated by the user operating an operation unit (not shown). Priority may be set.

  FIG. 11 is an explanatory diagram schematically showing an example of an operation screen for determining the upper limit value of the ink discharge amount. The operation screen 700 is displayed on the display unit 400 when, for example, the user selects a menu for “determining the upper limit value of the ink ejection amount” from the menu screen of various functions of the printing apparatus 200 displayed on the display unit 400. Is done. As shown in FIG. 11, on the operation screen 700, a menu PM1 for setting a paper type, a setting field E1 for setting a priority object (priority in the present embodiment), and user designation are enabled. A check box CB1 for setting, a setting field E2 for setting the ink duty, an OK button SB1, and a cancel button SB2 are provided.

  The menu PM1 is configured such that the user selects and inputs desired contents in a pull-down menu format. The menu PM1 displays names of various paper types that can be used in the printing apparatus 200, such as plain paper, photographic paper, and postal glossy postcards.

  The setting field E1 is configured such that the user selects and inputs a priority target of each avoidance target element in a radio button format. In the example shown in FIG. 11, the overflow radio button RB1 and the color saturation radio button RB4 are each set to ON. Further, the bleeding radio button RB2 and the aggregation radio button RB3 are set to OFF. In this example, the avoidance target element selected as the priority target has a higher priority than the avoidance target element that is not selected. That is, in the setting field E1, selecting the priority target avoidance element using the radio button is equivalent to setting the priority level of the avoidance target element to be selected high.

  The check box CB1 is configured such that the user selects and inputs valid / invalid specified by the user in a check box format. “User specified” enables a method in which the user sets the ink duty of each ink color and determines the upper limit value of the ink discharge amount that satisfies the set ink duty as the upper limit value of the ink discharge amount. It is specification of whether to do. In the example shown in FIG. 11, when the check box CB1 is checked, that is, when the user designation is valid, the setting column E2 for setting the ink duty of each ink color is valid. On the other hand, when the check box CB1 is not checked, that is, when the user designation is invalid, the ink duty of each ink color is set to a default value preset in the control unit 321.

  The setting field E2 is configured such that the user inputs the ink duty of each ink color in a text box format. The setting field E2 includes an input box PB1 for inputting the ink duty of cyan ink, an input box PB2 for inputting the ink duty of magenta ink, an input box PB3 for inputting the ink duty of yellow ink, And an input box PB4 for inputting the ink duty of the black ink. In the present embodiment, the ink duty that can be set in the setting column E2 is in the range of 0% to 200%. In the example shown in FIG. 11, 100 is input in the input box PB1. Further, 150 is input to the input box PB2, 160 to the input box PB3, and 160 to the input box PB4.

  When the user selects the OK button SB1, ink discharge amount upper limit determination processing is executed based on the input set values. When the user selects the cancel button SB2, the ink discharge amount upper limit determination process is not executed, and the menu screen of various functions of the printing apparatus 200 is displayed on the display unit 400. In the present embodiment, the operation screen 700 corresponds to a user interface in a means for solving the problem.

  The printing apparatus 200 according to the second embodiment having the above configuration has the same effects as the printing apparatus 200 according to the first embodiment. In addition, since the display unit 400 displays the priority when determining the upper limit value of the ink ejection amount, the priority can be confirmed in the printing apparatus 200, and the convenience for the user can be improved. Further, since the operation screen 700 for setting the priority is provided, the priority can be set in the printing apparatus 200, and the convenience for the user can be improved. Furthermore, since the operation screen 700 has radio buttons for setting priorities, it is possible to reduce the operation load when setting priorities and improve user convenience.

C. Variations:
C1. Modification 1:
FIG. 12 is an explanatory diagram schematically illustrating an example of an operation screen for determining the upper limit value of the ink discharge amount in the first modification. The operation screen 700a in Modification 1 is different from the operation screen 700 of the second embodiment in that a setting field E1a is provided instead of the setting field E1. Since the other structure in the operation screen 700a of the modification 1 is the same as that of the operation screen 700 of the second embodiment, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.

  The setting field E1a is configured such that the user selects and inputs a priority target of each avoidance target element in a text box format. The setting column E1a differs from the setting column E1 in the second embodiment in that priority is set as the priority of each avoidance target element. The setting field E1a includes an input box PB5 for inputting an overflow priority, an input box PB6 for inputting a bleeding priority, an input box PB7 for inputting an aggregation priority, and color saturation. And an input box PB8 for inputting priorities. In this embodiment, the priority order can be adjusted in the range of 1 to 4. Note that the range that can be set as the priority order may be a value corresponding to the number of elements to be avoided. In the example shown in FIG. 12, 2 is input to the input box PB5. Further, 1 is input to the input box PB6, 4 is input to the input box PB7, and 3 is input to the input box PB8. In the first modification, the input boxes PB5 to PB8 correspond to input units in the means for solving the problem.

  The configuration of Modification 1 having the above configuration has the same effects as those of the second embodiment. In addition, since the operation screen 700a has input boxes PB5 to PB8 for inputting the priority as the priority order, the priority order desired by the user can be easily input, and the convenience for the user can be improved.

  The configuration of the operation screens 700 and 700a in the second embodiment and the first modification is not limited to the examples illustrated in FIGS. For example, the priority may be set using a check box and a pull-down menu. Further, for example, the check box CB1 for validating the user designation may be omitted. For example, the user may set the priority on the display unit 400. Even with these configurations, the same effects as those of the second embodiment and the first modification can be obtained.

C2. Modification 2:
In each of the embodiments described above, the ejection amount upper limit determination unit 326 determines the lowest occurrence non-occurrence upper limit value among the non-occurrence upper limit values as the upper limit value of the ink ejection amount. It is not limited. For example, the non-occurrence upper limit value among the respective non-occurrence upper limit values may be determined as the upper limit value of the ink ejection amount, or the average value of the respective non-occurrence upper limit values may be determined as the upper limit value of the ink ejection amount. You may decide. Further, for example, predetermined weighting may be performed according to the priority, and an average value of each non-occurrence upper limit value considering each weight may be determined as the upper limit value of the ink ejection amount. In addition, the upper limit value of the ink ejection amount may be determined using a predetermined calculation formula, for example, a determinant. In these configurations as well, since the upper limit value of the ink ejection amount is determined based on at least one non-occurrence upper limit value among the respective non-occurrence upper limit values, the occurrence of at least one avoidance target element can be suppressed, and each of the above-described implementations There is an effect similar to the form.

C3. Modification 3:
In each of the above embodiments, ink overflow, ink bleeding, ink aggregation, and ink color saturation are used as elements to be avoided, but the present invention is not limited to this. For example, when printing is performed by ejecting only one color of ink, among the above-described elements to be avoided, agglomeration of ink is omitted, ink overflow, ink bleeding, and ink color. Saturation may be used. Even in such a configuration, the upper limit value of the ink ejection amount is determined based on at least one non-occurrence upper limit value among the non-occurrence upper limit values, as in the second modification. And the same effect as modification 2 is produced.

C4. Modification 4:
In the above embodiments, the configuration of the solid test pattern 631 is not limited to the configuration shown in FIG. Further, the configuration of the test pattern 632 with lines is not limited to the configuration shown in FIG. For example, not all the test areas 501 to 505 and 511 to 515 may be provided, and a configuration having at least one test area may be used. Further, for example, the print density and the ink color to be ejected in each of the test areas 501 to 505 and 511 to 515 may be different from the examples shown in FIGS. Further, for example, all the solid regions of the solid regions MCAr1 to MCAr4 may not be provided. That is, in general, the test pattern determines the first determination area for determining whether ink overflows, whether ink bleeds, and whether ink aggregates, and whether ink color saturation exists. If it is the structure which has at least 1 determination area | region among the 2nd determination area | region for this, there exists an effect similar to said each embodiment.

C5. Modification 5:
In each of the above embodiments, the printing apparatus 200 includes the imaging unit 232, but the imaging unit 232 may be omitted. In this case, the manufacturer of the printing apparatus 200 causes the scanner or the like to read the test medium 601 on which the test pattern 632 with lines is printed, and obtains the obtained imaging information 333 from the scanner or the like via a predetermined recording medium or network. You may send to the printing apparatus 200. With such a configuration, the manufacturing cost of the printing apparatus 200 can be kept low.

C6. Modification 6:
In each of the embodiments described above, the printing apparatus 200 includes the color measurement unit 233, but the color measurement unit 233 may be omitted. For example, the imaging unit 232 may be configured to function as the color measurement unit 233. With such a configuration, the manufacturing cost of the printing apparatus 200 can be kept low.

C7. Modification 7:
In each of the above embodiments, the printing apparatus 200 includes the storage unit (memory 330), but the storage unit may be omitted. In this case, each time the ink discharge amount upper limit determination process is executed, the same effect as that of each of the above-described embodiments is obtained by executing the imaging of the test medium 601 and the color measurement of the test medium 600, respectively. .

C8. Modification 8:
In each of the above embodiments and Modification 1, the printing apparatus 200 includes the display unit 400, but the display unit 400 may be omitted. In this case, for example, the operation screens 700 and 700a may be displayed on the display device of the print control apparatus 100. Even with such a configuration, the same effects as those of the above-described embodiments and Modification 1 are obtained.

C9. Modification 9:
In each of the above embodiments, the nozzle rows 70C, 70M, 70Y and 70K are arranged along the sub-scanning direction Y, but the present invention is not limited to this. For example, each nozzle row may be arranged along the main scanning direction X, or may be arranged along a direction intersecting the main scanning direction X and the sub-scanning direction Y.

C10. Modification 10:
In each of the above embodiments, the printing apparatus 200 performs printing with four colors of ink (cyan, magenta, yellow, and black), but the present invention is not limited to this. The number of ink colors used may be different from the above.

C11. Modification 11:
In each of the above embodiments, the printing apparatus 200 is a printing apparatus before shipment, but may be a printing apparatus after shipment. That is, the above-described ink discharge amount upper limit determination process may be performed at the user's home.

C12. Modification 12:
In each of the above embodiments, the ink duty of each ink color is determined as the upper limit value of the ink ejection amount, but the present invention is not limited to this. The upper limit value of the ink ejection amount may be determined, for example, as a dot size or a dot amount. Even with such a configuration, the same effects as those of the above embodiments can be obtained.

C13. Modification 13:
In each of the above-described embodiments, another device may have at least a part of the functions of the printing device 200. For example, some functions of the overflow upper limit calculation unit 322, the bleeding upper limit calculation unit 323, the aggregation upper limit calculation unit 324, the color saturation upper limit calculation unit 325, and the discharge amount upper limit determination unit 326 in the above embodiment The structure which an apparatus has may be sufficient. In such a configuration, the other apparatus corresponds to the print control apparatus 100 or a color conversion table creation apparatus (not shown) as an example. For example, the print control apparatus 100 and the color conversion table creation apparatus may be configured to have all the functions of the control unit 321. Even in these configurations, the same effects as those of the embodiment can be obtained.

C14. Modification 14:
In the first embodiment, the discharge amount upper limit determination unit 326 is based on the non-occurrence upper limit values calculated for each of ink overflow, ink bleeding, ink aggregation, and ink color saturation. Although the upper limit value of the ink discharge amount has been determined, the present invention is not limited to this. For example, as an element to be avoided, the ink overflow amount and the ink bleeding may be omitted, and the upper limit value of the ink discharge amount may be determined based on the non-occurrence upper limit values of ink aggregation and ink color saturation. Good. In addition, for example, as an element to be avoided, ink bleeding is omitted, and the upper limit value of the ink discharge amount is determined based on the non-occurrence upper limit values of ink overflow, ink aggregation, and ink color saturation. May be. That is, in general, a non-occurrence upper limit value that is an upper limit value of an ink discharge amount at which at least one of ink overflow, ink bleeding, and ink aggregation does not occur, and an ink discharge amount that does not cause ink color saturation If the configuration is such that the upper limit value of the ink ejection amount is determined based on the non-occurrence upper limit value that is the upper limit value, the same effects as those of the first embodiment can be obtained.

C15. Modification 15:
In the second embodiment, the priority is set for each avoidance target element, but the present invention is not limited to this. For example, as an avoidance target element, ink overflow and ink bleeding may be omitted, and priority may be set for ink aggregation and ink color saturation. Further, for example, as an avoidance target element, ink bleeding may be omitted, and priority may be set for ink overflow, ink aggregation, and ink color saturation. That is, in general, a priority is set when determining the upper limit value of the ink discharge amount for at least one of ink overflow, ink bleeding, and ink aggregation and ink color saturation. If it is the structure which has it, there exists an effect similar to the said 2nd Embodiment.

C16. Modification 16:
In each of the above embodiments, the imaging unit 232 and the color measurement unit 233 are provided in the carriage 230, but the present invention is not limited to this. For example, one of the imaging unit 232 and the color measurement unit 233 may be provided on a moving body different from the carriage 230. Further, for example, in the casing of the printing apparatus 200, the state on the print medium P may be fixed at a position where imaging or colorimetry can be performed. Even in such a configuration, the same effects as in the above embodiment can be obtained. In addition, each member can be reduced in size.

C17. Modification 17:
In each of the above embodiments, the first threshold value, the second threshold value, the third threshold value, and the fourth threshold value are each based on the results of sensory evaluation using a plurality of test patterns printed on the print medium P. However, the present invention is not limited to this. For example, each threshold value may be determined by displaying a user interface (setting screen) for setting each threshold value on the display unit 400 and inputting an arbitrary value by the user. In this configuration, each threshold value may be determined by the user selecting a desired threshold value from a menu for setting the threshold value. Even in such a configuration, the same effects as those of the above embodiments can be obtained.

  The present invention is not limited to the above-described embodiments and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments and the modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

  70 ... Nozzle row, 70C ... Nozzle row, 70K ... Nozzle row, 70M ... Nozzle row, 70Y ... Nozzle row, 71 ... Nozzle, 100 ... Print control device, 200 ... Printing device, 210 ... Supply unit, 220 ... Conveyance unit, 221... Transport roller 230. Carriage 231. Printing unit 232 Imaging unit 233 Colorimetry unit 240 Carriage moving unit 241 Carriage guide shaft 300 Control unit 310 Input / output interface 320 CPU, 321 ... control unit, 322 ... overflow upper limit calculation unit, 323 ... blur upper limit calculation unit, 324 ... aggregation upper limit calculation unit, 325 ... color saturation upper limit calculation unit, 326 ... discharge amount upper limit determination unit, 330 ... Memory, 331 ... Solid pattern data, 332 ... Pattern data with lines, 333 ... Imaging information, 334 ... Colorimetric information 340: Unit control circuit, 400: Display unit, 501 ... Test area, 502 ... Test area, 503 ... Test area, 504 ... Test area, 505 ... Test area, 511 ... Test area, 512 ... Test area, 513 ... Test area 514: Test area, 515: Test area, 600: Test medium, 601: Test medium, 631: Solid test pattern, 632: Test pattern with line, 700: Operation screen, 700a: Operation screen, BP1: Solid pattern Column, BP2 ... solid pattern column, BP3 ... solid pattern column, BP4 ... solid pattern column, BP5 ... solid pattern column, CB1 ... check box, CMYK ... ink color, E1 ... setting column, E1a ... setting column, E2 ... setting column LC ... line segment, LCAr1 ... line segment region, LCAr2 ... line segment region, LM ... line segment, LP ... Line pattern row, LP2 ... Line pattern row, LP3 ... Line pattern row, LP4 ... Line pattern row, LP5 ... Line pattern row, MCAr1 ... Solid region, MCAr2 ... Solid region, MCAr3 ... Solid region, MCAr4 ... Solid region, P ... Print medium, PB1 ... Input box, PB2 ... Input box, PB3 ... Input box, PB4 ... Input box, PB5 ... Input box, PB6 ... Input box, PB7 ... Input box, PB8 ... Input box, PM1 ... Menu, RB1 ... Overflow radio button, RB2 ... Blur radio button, RB3 ... Aggregation radio button, RB4 ... Color saturation radio button, SB1 ... OK button, SB2 ... Cancel button, SCAr ... Color saturation judgment area, X ... Main scanning direction, Y ... Sub scanning Direction, w1 ... width, w2 ... width, A ... dot, B ... dot, 101 ... dot, 10 2 ... dot, 103 ... dot, 104 ... dot, 105 ... dot, 105 '... dot, 106 ... dot, 107 ... dot, 108 ... dot, 109 ... dot, 109' ... dot, 110 ... dot, 111 ... dot, 111 '... dot, 112 ... dot, 113 ... dot, d1 ... distance, d2 ... distance

Claims (10)

A printing apparatus that prints an image by ejecting ink onto a print medium,
A printing unit for printing a test pattern for determining an upper limit value of the ink ejection amount;
An imaging unit for imaging a test medium on which the test pattern is printed;
A colorimetric unit for measuring the color of the test medium;
A discharge amount upper limit determining unit for determining the upper limit of the ink discharge amount;
Have
The discharge amount upper limit determination unit
The non-occurrence upper limit value as the upper limit value of the ink discharge amount that does not cause overflow of the ink, calculated based on the imaging information obtained by the imaging unit, and the ink discharge that causes no ink bleeding At least one non-occurrence upper limit value among the non-occurrence upper limit value as the upper limit value of the amount and the non-occurrence upper limit value as the upper limit value of the ink discharge amount at which the ink does not aggregate, and the colorimetric unit Based on the non-occurrence upper limit value as an upper limit value of the ink ejection amount that does not cause color saturation of the ink, calculated based on the colorimetric information obtained by the above, the at least one non-occurrence upper limit value And determining the upper limit value of the ink ejection amount,
Printing device. The printing apparatus according to claim 1,
Furthermore, a control unit is provided,
The controller is
The non-occurrence upper limit value that does not cause the overflow of the ink calculated by comparing the imaging information with the first threshold value and determining whether or not the ink overflows, the imaging information, and the second threshold value And comparing the non-occurrence upper limit value at which the ink bleeding does not occur calculated by determining the presence or absence of the ink bleeding with the imaging information and the third threshold value, Calculating at least one non-occurrence upper limit value among the non-occurrence upper limit values at which the aggregation of the ink does not occur, which is calculated by determining presence or absence,
By comparing the colorimetric information with a fourth threshold value to determine the presence or absence of color saturation of the ink, the non-occurrence upper limit value at which the color saturation of the ink does not occur is calculated.
The first threshold value, the second threshold value, the third threshold value, and the fourth threshold value are determined based on a result of sensory evaluation using the test pattern printed on the test medium. ,
Printing device. The printing apparatus according to claim 1 or 2,
The test pattern is
A first determination region for determining the presence or absence of overflow of the ink, the presence or absence of bleeding of the ink, and the presence or absence of aggregation of the ink;
A second determination region for determining the presence or absence of color saturation of the ink;
Having at least one determination area,
Printing device. In the printing apparatus as described in any one of Claim 1- Claim 3,
The ejection amount upper limit determination unit determines a non-occurrence upper limit value having the smallest value among the non-occurrence upper limit values as the upper limit value of the ink ejection amount.
Printing device. In the printing apparatus as described in any one of Claim 1- Claim 4,
Priorities for determining the upper limit value of the ink discharge amount for at least one of the ink overflow, the ink bleeding, and the ink aggregation and the color saturation of the ink are predetermined. Is set,
The discharge amount upper limit determination unit determines the upper limit of the ink discharge amount according to the priority;
Printing device. In the printing apparatus as described in any one of Claim 1- Claim 5,
Priorities for determining the upper limit value of the ink ejection amount in correspondence with at least one of the ink overflow, the ink bleeding, and the ink aggregation and the color saturation of the ink are set. A display unit for displaying;
Printing device. The printing apparatus according to claim 6.
A user interface for setting the priority;
Printing device. The printing apparatus according to claim 7.
The user interface has a radio button for setting the priority.
Printing device. The printing apparatus according to claim 7.
The user interface has an input unit for inputting the priority as a priority.
Printing device. The printing apparatus according to any one of claims 1 to 9,
A storage unit for storing the imaging information and the colorimetric information;
Printing device.