JP2012213053A - Print control method - Google Patents

Abstract

Colorimetric errors in calibration are detected with high accuracy and at high speed to prevent colorimetric errors.
An inspection target color patch provided on a reference chart printed by a printing device 20 in a reference state is subjected to a specific spectral reflectance (color patch applied to a cyan color material) using a color measurement device 30 in the reference state. For any color patch relating to magenta color material, any wavelength except 430 nm to 560 nm may be used, and for any color patch relating to yellow color material, any wavelength except 380 nm to 470 nm. The wavelength of the color patch applied to the black color material is any wavelength except 380 nm to 470 nm), and based on the color difference from the specific spectral reflectance of other adjacent color patches in the ink amount gradation, Detects abnormalities in printing or colorimetry of color patches to be inspected.
[Selection] Figure 3

Description

  The present invention relates to a printing control method, and in particular, a printing control method for causing a printing unit to print a chart provided with a color patch and detecting an abnormality related to printing or color measurement of the color patch based on a color measurement result of the color patch. About.

In order to perform color matching of a printed matter output from a printing apparatus, a color patch is printed by the printing apparatus, and a colorimetric value of the printed color patch is acquired using a colorimeter. At that time, the colorimetric value obtained from the color patch is due to the secular variation or malfunction of the discharge outlet of the color material, dust adhering to the printed material, misconfiguration of the colorimeter, malfunction of the colorimeter, etc. May be inappropriate.
As a method for dealing with such a problem, for example, a visual inspection is performed. However, since the user's subjectivity is used as a reference, the determination result is different, and it may be difficult to visually determine printing unevenness or the like.
As another method, standard colorimetric values and tolerances are set in advance in each color patch of the output color chart, and the colorimetric values obtained from the color patches are converted from the standard colorimetric values. There is a technique for notifying the user when the value is within the allowable error range (see, for example, Patent Document 1).

JP 2009-124458 A

In the method of Patent Document 1 described above, XYZ values (CIE), L ^* a ^* b ^* (CIE), and the like are used as colorimetric values. However, these colorimetric values are limited in calibration accuracy. Further, when the spectral reflectance distribution is used for highly accurate calibration, the calibration speed is reduced.

  The present invention has been made in view of the above problems, and provides a print control method capable of detecting a colorimetric error in calibration with high accuracy and high speed and preventing a colorimetric error.

  One aspect of the present invention is a printing control method for causing a printing unit to print a chart provided with a color patch and detecting an abnormality related to printing or color measurement of the color patch based on a color measurement result of the color patch. A color patch provided on the first chart printed by the printing unit in a reference state is acquired using a colorimetry unit in a reference state to obtain a spectral reflectance of a predetermined wavelength, and the color patch Based on the color difference from the spectral reflectance at a predetermined wavelength obtained by using the colorimetric unit in the reference state for the other color patches provided in the first chart adjacent to the color patch in the ink amount gradation. The color patch is configured to detect an abnormality related to printing or colorimetry, and the predetermined wavelength is 400 nm to 400 nm for a color patch related to a cyan color material. Any wavelength of 00 nm, any wavelength except for 430 nm to 560 nm for the color patch for magenta color material, and any wavelength except for 380 nm to 470 nm for the color patch for yellow color material The color patch relating to the black color material has a wavelength other than 380 nm to 470 nm.

  At the predetermined wavelength, the change degree of the spectral reflectance with respect to the change in the color material amount of each color material is smaller than the change degree at wavelengths other than the predetermined wavelength. Therefore, the spectral reflectance at the predetermined wavelength of the color patch that is the detection target of the abnormality related to printing or colorimetry, and the other provided in the first chart adjacent to the detection target color patch in the ink amount gradation The influence of the amount of change in spectral reflectance due to an abnormality in printing or color measurement on the color difference between the color patch and the spectral reflectance at a predetermined wavelength obtained using the colorimetric unit in the reference state is large. For example, if there is an abnormality related to the printing or colorimetry, the color difference between the spectral reflectances when there is no abnormality related to the printing or colorimetry varies greatly between positive and negative. Therefore, if there is an abnormality related to the printing or colorimetry, a spectrum at a predetermined wavelength obtained by using the colorimetry unit in the reference state for another color patch adjacent to the detection target color patch in the ink amount gradation is obtained. The magnitude relationship with the reflectance is reversed from the case where there is no abnormality related to the printing or color measurement. Therefore, it is possible to detect a colorimetric error of a patch with high accuracy and prevent a colorimetric error. Further, since the predetermined wavelength is used without using the entire spectral reflectance distribution, an abnormality can be detected at high speed.

  One of the selective aspects of the present invention is to detect the abnormality for each of a plurality of color patches, and cause the printing unit to print a third chart provided with only the color patch in which the abnormality is detected, A spectral reflectance at the predetermined wavelength is obtained for the color patch provided in the third chart using the colorimetric unit, and the first chart adjacent to the color patch in the color patch and the ink amount gradation. An abnormality related to printing or colorimetry of the color patch is detected based on a color difference from a spectral reflectance at a predetermined wavelength acquired using the colorimetric unit in a reference state with respect to another color patch provided in the color patch. It is supposed to be configured.

  In this configuration, the color patch in which an abnormality is detected is reprinted and remeasured. Accordingly, a normal spectral reflectance is acquired by reprinting / re-coloring for a color patch in which an abnormality is detected due to a temporary factor. On the other hand, for color patches in which an abnormality is detected due to a non-temporary factor, the abnormality is detected again even if reprinting / re-measurement is performed. Therefore, the cause of the abnormality can be limited. If the abnormality is temporary, a normal color measurement result of the color patch can be obtained.

  One of the selective aspects of the present invention is that the abnormality is detected for each of a plurality of color patches, and only the color patch where the abnormality is detected is provided at a printing position different from when the abnormality is detected. The third chart is printed on the printing section, the spectral reflectance at the predetermined wavelength is obtained for the color patches provided on the third chart using the color measuring section, and the color patch and the ink amount scale are obtained. Spectral reflectance at a predetermined wavelength acquired using the colorimetric unit in a reference state for the other color patches provided in the first chart or the third chart adjacent to the color patch in the tone An abnormality relating to printing or color measurement of the color patch is detected based on the color difference.

  Also in this configuration, the color patch in which an abnormality is detected is reprinted and remeasured. Accordingly, a normal spectral reflectance is acquired by reprinting / re-coloring for a color patch in which an abnormality is detected due to a temporary factor. In addition, the printing position and colorimetric position of the color patch where the abnormality is detected are different from the printing position and colorimetric position when printing and colorimetry is performed first, so the abnormality is detected due to positional factors. Even if it has been performed, the abnormality is resolved and a normal spectral reflectance is obtained. On the other hand, if an abnormality is detected due to a factor that is neither temporary nor positional, the abnormality is detected again even if reprinting / re-measurement is performed for the color patch in which the abnormality is detected. Therefore, the cause of the abnormality can be limited. If the abnormality is due to a temporary factor or a positional factor, a normal color measurement result of the color patch can be obtained.

  One of the selective aspects of the present invention is a value calculated by an interpolation operation using a color measurement result concerning a plurality of other color patches printed with a color material amount different from the color patch in which the abnormality is detected. The color measurement result of the color patch in which the abnormality is detected is complemented, and the color material amount of the color patch in which the abnormality is detected is associated with the color measurement result and stored in a predetermined storage medium. .

  In this configuration, the color measurement result of the color patch in which the abnormality is detected is subjected to an interpolation calculation using the color measurement results applied to a plurality of other color patches printed with a different color material amount from the color patch. In order to complement the result of the calculation as the color measurement result of the color patch in which the abnormality is detected, if the color patch in which the abnormality has occurred is a decimal number, the abnormality is not performed without performing reprinting or re-color measurement. Data in which the color material amount of the detected color patch is associated with the color measurement result can be created. Therefore, it is possible to speed up the output of the color measurement result while detecting the color measurement mistake of the patch with high accuracy and preventing the color measurement error.

  One of the selective aspects of the present invention is that the abnormality is detected for each of a plurality of color patches printed on a single print medium, and the color difference error is detected for at least one of the plurality of color patches. When a predetermined value is exceeded and an average of the color difference errors of the plurality of color patches does not exceed the predetermined value, a color measurement abnormality due to an external factor is notified to the user.

  According to this configuration, since the user is notified that the abnormality has occurred due to an external factor, the user can easily eliminate the abnormality factor. The error is at a predetermined wavelength acquired using the colorimetric unit in a reference state with respect to another color patch provided in the first chart adjacent to the color patch in the color patch and the ink amount gradation. Calculated based on the color difference from the spectral reflectance, for example, obtained using the colorimetric unit in the reference state for the other two color patches provided in the first chart adjacent to the color patch When the spectral reflectance at a predetermined wavelength is linearly interpolated, the difference from the spectral reflectance that comes to the ink amount gradation of the color patch to be inspected abnormally can be used as the color difference error. The external factor is not an abnormality caused by a printing unit, a color measuring unit, a device that controls the printing unit or the color measuring unit, a device that determines the presence or absence of an abnormality based on a color measurement result, etc. This means an external factor of the system configuration related to colorimetry and abnormality detection such as dust adhering to the print medium or damage to the color patch.

  One of the selective aspects of the present invention is that the abnormality is detected for each of a plurality of color patches printed on a single print medium, and the color difference error is detected for at least one of the plurality of color patches. When a predetermined value is exceeded and an average of the color difference errors of the plurality of color patches exceeds the predetermined value, a color measurement abnormality due to an internal factor is notified to the user.

  According to this configuration, the user is notified that the abnormality has occurred due to an internal factor, so that the user can easily eliminate the factor of the abnormality. The internal factor is an abnormality caused by a printing unit, a color measurement unit, a device that controls the printing unit or the color measurement unit, a device that determines the presence or absence of an abnormality based on a color measurement result, and the like. For color measurement and abnormality detection such as abnormal color material amount that the printing unit adheres to the print medium, aging deterioration of the printing unit, color measurement sensitivity of the color measurement unit, aging deterioration of the color measurement unit, etc. It means the internal factors of such system configuration.

  One of the selective aspects of the present invention is to record an error of the color difference of the color patch, and when the error tends to increase in the history, calibrate at least one of the printing unit and the colorimetric unit. It is configured to notify the user of the time.

  In this configuration, the color difference error in the color patch is recorded a plurality of times, and it is determined whether or not the error tends to increase. If the error tends to increase, the printing unit and the colorimetric unit are referred to. Notify the user that the system configuration may have deteriorated over time. Therefore, the user can grasp a guideline for calibrating or repairing the printing unit or the colorimetric unit.

  One of the selective aspects of the present invention is that the error of the color difference of the color patch is recorded as a history, and the variation of the error in the color patch in which the abnormality is detected is different from the variation tendency of the error in the history. When a tendency is shown, the user is notified of a colorimetric abnormality caused by an external factor.

  In this configuration, the color difference error in the color patch is recorded a plurality of times, and a negative error occurs in the color patch in the color patch even though the positive error dominates in the history. If there is a positive error in the color difference in the color patch in spite of a large number of error errors in the history, the abnormality causing the error is an external factor. Notify users. That is, an abnormality trend that gradually increases with use of the system configuration is grasped from the history, and by contrasting with such an abnormality tendency, an abnormality that occurs temporarily due to an external factor can be specified. Therefore, it becomes possible to notify the user of an abnormality caused by an external factor more accurately.

  One of the selective aspects of the present invention is to record an error of the color difference of the color patch, and a fluctuation tendency of an error applied to the color patch of a specific color material in the history applies to the color patch of another color material. When different from the fluctuation tendency of the error, the printing unit notifies the user of an abnormality in the amount of the specific color material to be adhered to the print medium.

  In this configuration, the color difference error in the color patch is recorded multiple times for each type of color material used for printing the color patch, and the color difference applied to the color patch printed with the specific color material is recorded. When the variation tendency of the error is different from the variation tendency of the error of the color difference applied to the color patch printed with another color material, it is determined that there is an abnormality in the amount of adhesion of the specific color material to the print medium, This is notified to the user. Therefore, the user can accurately grasp the cause of the abnormality, and the time required to eliminate the abnormality can be shortened.

  The above-described print control method is implemented as a part of another method or a print control device provided with means corresponding to each process, a print control device or a printing device provided with various data created by the print control method, or a measurement. Various modes such as being realized as a color device are included. The present invention also provides a print control system including at least one of the print control device, the print device, and the colorimetric device, a print control program that causes a computer to implement functions corresponding to the above-described method configuration, and records the print control program. It can also be realized as a computer-readable recording medium.

1 is a diagram illustrating a configuration of a printing system having a printing control apparatus. It is a block diagram which shows the structure of a host apparatus. It is a flowchart which shows the flow of reference data preparation. It is an example of the color patch arrangement | positioning in a reference | standard chart. It is a graph which shows the spectral reflectance distribution of the color patch printed with the some ink amount about cyan ink. It is a graph which shows the spectral reflectance distribution of the color patch printed with the some ink amount about magenta ink. It is a graph which shows the spectral reflectance distribution of the color patch printed about the yellow ink with the some ink amount. It is a graph which shows the spectral reflectance distribution of the color patch printed with the some ink amount about black ink. It is a figure explaining the fluctuation | variation of the spectral reflectance by a colorimetric mistake. It is a figure explaining the arrangement | positioning location of the error patch at the time of performing reprinting. It is a flowchart which shows the flow of color patch colorimetry. It is a figure which shows an example of UI screen which performs manual removal.

Hereinafter, embodiments of the present invention will be described in the following order.
(1) Configuration of the present embodiment:
(2) Creation of reference data:
(3) Colorimetric error detection:
(4) Modification:

(1) Configuration of the present embodiment:
《Printing system》
FIG. 1 illustrates the configuration of a printing system having a print control apparatus.
In the printing system S <b> 1 illustrated in FIG. 1A, a printing device 20 and a color measurement device 30 are connected to the host device 10. For example, the host device 10 is constituted by a computer such as a personal computer, the printing device 20 is constituted by an ink jet printer, and the color measuring device 30 is constituted by a color colorimeter. In the printing system S1, the host device 10 constitutes a print control device that holds information such as ink amount data for reference patch printing, the printing device 20 constitutes a printing unit, and the color measurement device 30 represents a color measurement unit. Configure.

  In the printing system S2 shown in FIG. 1B, a printing device 20 and a color measurement device 30 are connected. For example, the printing apparatus 20 includes cyan (C), magenta (M), yellow (Y), and black (K) inks, and is configured by an ink jet printer capable of printing using these CMYK inks. . Further, for example, the color measuring device 30 is configured by a color color measuring machine. In the printing system S2, the printing device 20 or the color measurement device 30 holds information such as ink amount data for reference patch printing, and the devices holding these information constitute a printing control device, and the printing device Reference numeral 20 constitutes a printing unit, and the color measuring device 30 constitutes a color measuring unit. In the following description, the configuration of FIG. 1A is taken as an example.

<Host device>
FIG. 2 is a block diagram illustrating the configuration of the host device. The main part of the host device 10 is substantially constituted by a computer 100. Specifically, the CPU 101 included in the computer 100 reads a program (reference data creation program, patch colorimetry program, etc.) stored in the hard disk 103 or the like, and executes a calculation according to the program while developing the program in the RAM 102. Thus, the functions of the reference patch database creation module 110 (reference patch DB creation module 110) and the colorimetric error detection module 120 are realized. The hard disk 103 holds the above-described ink amount data for reference patch printing, and also stores information such as a reference patch database DB1 and a color difference history database DB2 created during the creation of each reference data described later.

  A display device (for example, a liquid crystal display) (not shown) is connected to the computer 100, and a UI (user interface) necessary for each process is displayed on the display device. Furthermore, an input device (for example, a mouse or a keyboard) (not shown) is connected to the computer 100, and information necessary for each process is input via the input device. The computer 100 is connected to a printing device 20 (such as an ink jet printer) and a color measurement device 30.

  The reference patch DB creation module 110 includes a reference chart printing unit 111, a colorimetric data acquisition unit 112, a colorimetry error determination unit 113, and a database creation unit 114. The colorimetric error detection module 120 includes a test chart printing unit 121, a colorimetric data acquisition unit 122, a colorimetry error determination unit 123, a history database creation unit 124, and a notification unit 125.

(2) Creation of reference data:
FIG. 3 is a flowchart showing a flow of creating reference data. In creating the reference data, a reference patch database DB1 used for finding a colorimetric error in future patch colorimetry is created. The reference patch database DB1 is data that defines the correspondence between the ink amount data and the colorimetric values, and may hereinafter be referred to as a reference LUT. This process is started when an input for instructing creation of a reference LUT is received from the user via the input device. It is assumed that the printing device 20 and the color measurement device 30 are in a calibrated reference state at the time of creation of the reference data.

  When the process is started, the reference chart printing unit 111 creates print data of the reference chart BC and outputs it to the printing apparatus 20 (S10). The printing apparatus 20 performs printing based on the print data (S20), and forms an image of the reference chart BC on the surface of the print medium. The reference chart BC is formed in an area in which colorimetry can be performed by the colorimetry device 30 for colorimetry described later. In creating the reference data, the reference chart BC constitutes the first chart.

<< Explanation of reference chart >>
FIG. 4 is an example of the color patch arrangement in the reference chart. In the figure, a plurality of color patches are formed on the reference chart BC for each color ink. Color patches C01 to C16 are color patches for cyan ink, color patches M01 to M16 are color patches for magenta ink, color patches Y01 to Y16 are color patches for yellow ink, and color patches K01 to K16 are black. This is a color patch for ink. In each color patch, the amount of ink adhering to the print medium gradually decreases as the number after the letter indicating the ink color shown in FIG. 4 increases, and the spectral reflection obtained by measuring the color patch of each color. If printing and colorimetry are normally performed, the rate gradually decreases as the number after the letter indicating the ink color of each color patch increases.

When the reference chart BC is printed, the operator sets the print medium on which the reference chart BC is printed on the color measurement device 30 and causes the color measurement device 30 to perform color measurement (S30). The color measurement device 30 sequentially measures each color patch to obtain the spectral reflectance distribution R (λ) of each color patch, and outputs data of the spectral reflectance distribution R (λ) to the host device 10.
The colorimetric data acquisition unit 112 acquires the spectral reflectance distribution R (λ) input to the host device 10. The colorimetric error determination unit 113 acquires a spectral reflectance in a specific wavelength range specific to the ink color (hereinafter referred to as a specific spectral reflectance) from the spectral reflectance distribution R (λ) of each color patch (hereinafter referred to as a specific spectral reflectance). S40). The specific wavelength range is different for each ink color as described below.

《Explanation of specific wavelength range》
FIG. 5 is a graph showing the spectral reflectance distribution of a color patch printed with a plurality of ink amounts for cyan ink, and FIG. 6 shows the spectral reflectance distribution of a color patch printed with a plurality of ink amounts for magenta ink. FIG. 7 is a graph showing a spectral reflectance distribution of a color patch printed with a plurality of ink amounts for yellow ink, and FIG. 8 is a spectral reflection of a color patch printed with a plurality of ink amounts for black ink. It is a graph which shows rate distribution.

  As shown in FIG. 5, the decrease in spectral reflectance in the wavelength region A (C) is smaller than that in the wavelength region B (C) in the cyan ink, and the spectral region in the wavelength region A (M) applied to the magenta ink as shown in FIG. The degree of decrease in the reflectance is smaller than the wavelength range B (M), and as shown in FIG. 7, the degree of decrease in the spectral reflectance in the wavelength range A (Y) applied to the yellow ink is smaller than that in the wavelength range B (Y). As shown in FIG. 4, the degree of decrease in the spectral reflectance in the wavelength region A (K) applied to the black ink is smaller than that in the wavelength region B (Y). That is, the spectral reflectance distribution of the color patches of each color gradually decreases as the ink amount increases, but the degree of decrease in the spectral reflectance is different in each wavelength region.

Specifically, the wavelength λ of the wavelength region A (C) is “400 nm ≦ λ ≦ 600 nm”, and the wavelength λB (C) of the wavelength region B (C) is “λ ≦ 400 nm, 600 nm ≦ λ”. The wavelength λ of the wavelength region A (M) is “λ ≦ 430 nm, 560 nm ≦ λ”, the wavelength λB (M) of the wavelength region B (M) is “430 nm ≦ λ ≦ 560 nm”, and the wavelength region A (Y ) Is “λ ≦ 380 nm, 470 nm ≦ λ”, the wavelength λ of the wavelength region B (Y) is “380 nm ≦ λ ≦ 470 nm”, and the wavelength λ of the wavelength region A (K) is “380 nm ≦ λ ≦ 730 nm ”. In the present embodiment, the wavelength ranges A (C), A (M), A (Y), A (K) constitute the first wavelength range of each ink color, and the wavelength ranges B (C), B ( M) and B (Y) constitute the second wavelength range of each ink color.
Hereinafter, the wavelength region A (C), the wavelength region A (M), the wavelength region A (Y), the wavelength region A (K), the wavelength region A, the wavelength region B (C), the wavelength region B (M), The wavelength range B (Y) and the wavelength range B (K) may be collectively referred to as the wavelength range B.

  Either the wavelength range A or the wavelength range B determined as described above may be set as the specific wavelength range, but each wavelength range has the following merits, for example. For example, when the wavelength region A is a specific wavelength region, the difference in spectral reflectance between adjacent color patches in the ink amount gradation becomes small, so when a colorimetric error occurs, the adjacent color in the ink amount gradation. A reversal of the magnitude relationship is likely to occur between the specific spectral reflectance of the patch. That is, as will be described later, when it is determined that there is a colorimetric error in the color patch to be inspected by detecting a reversal of the magnitude relationship between the specific spectral reflectances of adjacent color patches in the ink amount gradation. preferable. On the other hand, when the wavelength region B is a specific wavelength region, the difference in spectral reflectance between adjacent color patches in the ink amount gradation increases, so that the spectral reflectance can be accurately calculated during linear interpolation described later. it can.

<Detection of colorimetric error>
Next, the colorimetric error determination unit 113 inspects a colorimetric error based on the spectral reflectance distribution acquired from each color patch (S50). Causes of color measurement errors include color measurement errors due to external factors in the system (damage of the color patch to be measured, dust adhering to the color patch to be measured, etc.), and color measurement errors due to internal system factors (print unevenness) , Abnormality or deterioration of the colorimeter, etc.) and an erroneous color measurement method of the worker. The inspection of the colorimetric error is performed by comparing with the spectral reflectance of the adjacent color patch in the ink amount gradation.

FIG. 9 is a diagram for explaining a change in spectral reflectance due to a colorimetric error. In the figure are plotted the relationship between the specific spectral reflectance according to any one of the ink colors color patches R and (lambda _S) and the ink amount gradation I _S. As shown in FIG. 9A, the specific spectral reflectances of the color patch P _{x to be} inspected are spectral reflectances R (λ _S ) _x0 , R (λ _S ) _x1 , R (λ _S ) _x2 The specific spectral reflectance of the color patch P _x-1 adjacent to the low gradation side of the inspection target color patch P _{x in} the tone is the spectral reflectance R (λ _S ) _x−1, and the inspection target color patch in the ink amount gradation the specific spectral reflectance of the color patch _{P x + 1} adjacent to the high tone of the P _x is the spectral reflectance _{R (λ S) x + 1} . Further, a specific spectral reflectance when there is no colorimetric errors in the inspection target color patches Px and the spectral reflectance R (λ _{S) x0,} the specific spectral reflectance when there is a colorimetric errors in the inspection target color patch P _x Spectral reflectances R (λ _S ) _x1 and R (λ _S ) _x2 are used.

The Figure 9 (b) is plotted the relationship between the specific spectral reflectivity R and (lambda _S) and the ink amount gradation I _S when colorimetry miss no inspection target color patch P _x. As shown in the figure, the spectral reflectance R (λ _S) spectral reflectance from _x-1 R (λ _S) difference ΔR by subtracting the _{x0 (λ S) x-1} , x0 and the spectral reflectance R (lambda _S ) spectral reflectance from _{x0 R (λ S) x +} 1 obtained by subtracting the difference _{ΔR (λ S) x0, x} + 1 substantially equal to the difference _{ΔR (λ S) x-1} , x0 and the difference _{ΔR (λ S) x0, x} + 1 Falls within a certain range. That is, if the upper limit threshold of these differences is ΔR (λ _S ) thh (not shown) and the lower limit threshold is ΔR (λ _S ) thl (not shown), the difference ΔR (λ _S ) _{x−1, x0} is ΔR ( λ _S ) thl <ΔR (λ _S ) _{x−1, x0} <ΔR (λ _S ) thh is satisfied, and the difference ΔR (λ _S ) _{x0, x + 1} is also ΔR (λ _S ) thl <ΔR (λ _S ) The relationship _{x0, x + 1} <ΔR (λ _S ) thh is satisfied. The upper threshold value ΔR (λ _S ) thh and the lower threshold value ΔR (λ _S ) thl are determined so that, for example, the magnitude relationship between R (λ _S ) _x−1 and R (λ _S ) _x0 is not interchanged. . If the magnitude relationship between R (λ _S ) _x0 and R (λ _S ) _{x + 1} is not switched, the upper threshold value ΔR (λ _S ) thh is 2 of ΔR (λ _S ) _{x−1, x0} . The lower limit threshold value ΔR (λ _S ) thl is set to 0. Of course, the threshold value can be arbitrarily set. However, in the following, the upper limit threshold ΔR (λ _S ) thh is set to be twice as large as ΔR (λ _S ) _{x−1, x0} , and the lower limit threshold is ΔR (λ _S ). A case where thl is 0 will be described as an example.

In FIG. 9C, there is a colorimetric error for the color patch P _{x to be} inspected, and the specific spectral reflectance R (λ _S ) when the specific spectral reflectance is reduced as in the spectral reflectance R (λ _S ) _x1. It is plotted the relationship between the ink amount gradation I _S and. As shown in the figure, the difference ΔR (λ _{S) x1, x1} minus the spectral reflectance R (λ _{S) x1} from the spectral reflectance R (λ _{S) x1} is, ΔR (λ _S) thh _{<ΔR (λ S) x1,} x1 satisfies the relationship of the spectral reflectance R (λ _{S) x1} from the spectral reflectance R (λ _S) the difference obtained by subtracting the _{x + 1 ΔR (λ S)} x1, x + 1 is, ΔR The relationship (λ _S ) _x1 , _{x + 1} <ΔR (λ _S ) thl is satisfied. That is, the spectral reflectance R (λ _S ) _x1 of the color patch P _{x to be} inspected does not satisfy both the upper threshold and the lower threshold, and the magnitude relationship between R (λ _S ) _x1 and R (λ _S ) _{x + 1} It shows that it has been replaced.

Further, in FIG. 9D, there is a colorimetric error for the color patch P _{x to be} inspected, and the specific spectral reflectance R (λ) when the specific spectral reflectance increases as in the spectral reflectance R (λ _S ) _x2. It is plotted the relationship between _S) and the ink amount gradation I _S. As shown in the figure, the difference _{ΔR (λ S) x-1} , x2 obtained by subtracting the spectral reflectance R (λ _{S) x2} from the spectral reflectance R (λ _{S) x-1} is, ΔR (λ _{S) x -1, x2 <ΔR (λ S} ) satisfies the relationship of thl, the spectral reflectance R (λ _{S) x2} from the spectral reflectance R (λ _S) difference by subtracting the _{x + 1 ΔR (λ S)} x2, x + 1 is, [Delta] R (Λ _S ) thh <ΔR (λ _S ) _{x2, x + 1} is satisfied. That is, the spectral reflectance R (λ _S ) _x2 of the color patch P _{x to be} inspected does not satisfy both the upper threshold and the lower threshold, and the magnitude of R (λ _S ) _x2 and R (λ _S ) _x−1 . Indicates that the relationship is changing.

As described above, when a colorimetric error occurs in the color patch P _{x to be} inspected, the difference in specific spectral reflectance between adjacent color patches in the ink amount gradation becomes the upper limit threshold ΔR (λ _S ) thh and the lower limit threshold ΔR (λ _S ) is outside the range of at least one of thl. Therefore, colorimetry miss determination unit 113 calculates a difference between the specific spectral reflectance of the color patch adjacent to each other in a particular spectral reflectance and the inspection target color patch P _x and the ink amount gradation inspected color patch P _x If the difference is within the range from the upper limit ΔR (λ _S ) thh to the lower limit ΔR (λ _S ) thl, it is determined that the color patch Px to be inspected has no colorimetric error, and the difference is determined to be the upper limit ΔR (λ _S ) If it is outside the range from thh to the lower limit ΔR (λ _S ) thl, it can be determined that there is a colorimetric error in the color patch Px to be inspected.

Of course, if there is a reversal of the magnitude relationship between specific spectral reflectances of adjacent color patches in the ink amount gradation, it is determined whether there is a colorimetric error in the color patch to be inspected without obtaining a color difference. You can also. Specifically, the specific spectral reflectance of the color patch P _x to be inspected is smaller than the specific spectral reflectance R (λ _S ) _{x−1 of} the color patch P _x−1 , and the specific spectral reflection of the color patch P _{x + 1.} When the ratio R (λ _S ) _{x + 1} is greater, it is determined that the color patch Px to be inspected has no colorimetric error, and the specific spectral reflectance applied to the color patch P _x is the specific spectral reflectance of P _x−1. If it is larger than R (λ _S ) _x−1 or smaller than the specific spectral reflectance R (λ _S ) _{x + 1 of the} color patch P _{x + 1} , it is determined that the color patch P _x to be inspected has a colorimetric error. can do.

  If it is determined in step S50 that any one of the color patches has a colorimetric error, the colorimetric error determination unit 113 determines the specific spectral reflectance relating to the color patch in which the colorimetric error is found (hereinafter also referred to as an error patch). Is deleted (S60). Then, interpolation calculation is performed to complement the specific spectral reflectance applied to the error patch. Various known calculation methods can be employed for the interpolation calculation. For example, for a specific spectral reflectance obtained from another color patch in the ink color in which the error patch is found, the ink amount gradation and the spectral reflectance are calculated. Can be interpolated in the space with the axis as the axis, and the spectral reflectance corresponding to the ink amount gradation of the error patch in the calculated straight line can be complemented as the specific spectral reflectance of the error patch.

  Of course, instead of the above-described step S60, the reference chart printing unit 111 may perform reprinting and recoloring for the error patch (S60 ′), and the specific spectral reflectance data may be acquired again (S20 to S40). . In this case, as shown in FIG. 10, it is preferable to print the error patch at a position different from the position printed when the colorimetric error is found. That is, the error patch is printed at the position where the color patch was not printed at the time of the previous printing when reprinting. As a result, the color measurement position is also different from the previous color measurement position. By printing the error patch print position at a position different from that at which the color measurement error was found, it is possible to prevent the color measurement error from occurring again in relation to the print position or the color measurement position. When reprinting / recoloring is performed, it is determined again whether or not there is a colorimetric error (S40). Note that in reprinting and recoloring, only error patches may be printed, or all other patches may be printed. In this way, when reprinting / colorimetry is performed, a chart in which only error patches are printed constitutes the second chart in the creation of reference data, and when an error patch is detected as a colorimetric error A chart that is printed at a position different from the position printed at the time constitutes a third chart in creating the reference data.

  If it is determined in step S50 that there is no color measurement error in any of the color patches, the database creation unit 114 creates the reference patch database DB1 (S70). The reference patch database DB1 includes the print mode of the printing apparatus that outputs the color patch, the model-specific data (model name, serial number, etc.) of the printing apparatus and the colorimetry apparatus 30, the ink amount data and the specific spectral reflectance for each color patch. Are associated with each other. The reference patch database DB1 is stored in a storage medium (hard disk 103) of the host device 10.

(3) Colorimetric error detection:
FIG. 11 is a flowchart showing the flow of color patch colorimetry. This process is started when an input for instructing printing and color measurement of the reference patch is received from the user via the input device. When the process is started, the test chart printing unit 121 prints a test chart provided with a color patch (S110). The ink amount data of the color patch provided in the test chart is not limited to the ink amount data included in the reference chart described above, and any ink amount data can be adopted. When the test chart is printed, the operator sets the test chart on the color measuring device 30 and performs color measurement with the color measuring device 30 (S120). The color measuring device 30 sequentially outputs the spectral reflectance distribution obtained by measuring each color patch provided on the test chart to the host device 10. Note that in the detection of a colorimetric error, the test chart forms the first chart.

  The colorimetric data acquisition unit 122 acquires spectral reflectance distribution data measured for each color patch provided in the test chart input to the host device 10. Then, the colorimetric error determination unit 123 refers to the reference patch database DB1 created in the above-described reference data creation process, and the specific spectral reflectance corresponding to the ink amount gradation of each color patch of the test chart (hereinafter, referred to as “color measurement error determination unit 123”). (Referred to as reference specific spectral reflectance) (S130). As for the specific spectral reflectance corresponding to the ink amount gradation not registered in the reference patch database DB1, an interpolation operation using the specific spectral reflectance corresponding to the ink amount gradation adjacent to the ink amount gradation to be calculated. Get by. The reference specific spectral reflectance acquired in this way becomes a reference value for detecting a colorimetric error in each color patch.

  When the reference specific spectral reflectance is acquired, the colorimetric error determination unit 123 includes a specific spectral reflectance included in the spectral reflectance distribution acquired from the colorimetric device 30 in step S120 (hereinafter referred to as an actual measured spectral reflectance). Are compared with the reference specific spectral reflectance (S140). Specifically, a color difference ΔC (not shown) between the measured specific spectral reflectance and the reference specific spectral reflectance is calculated for each color patch of the test chart, and the color difference ΔC is set to a predetermined threshold ΔCth (not shown). ), It is determined whether the patch is an error patch (S150). If it is determined that there is an error patch, the notification unit 125 is notified of a colorimetric error to the user (S170 to S250). The notification of the color measurement mistake is performed by, for example, displaying a predetermined message on a display device (not shown).

  On the other hand, if there is no color patch in which the color difference calculated in step S140 exceeds the preset color difference threshold, the user is not notified (S150: No), and the history database creation unit 124 is notified of the color difference ΔC. The color difference history database DB2 records the result (S270), the color measurement error determination unit 123 displays the color measurement result of the test chart on the screen of the host device 10 (S280), and the process for detecting the color measurement error ends. The color difference history database DB2 records the color difference ΔC related to the color patch colorimetry performed so far. By referring to the color difference history database, the tendency of changes in the color difference ΔC so far can be grasped. be able to.

  In notifying of a colorimetric error, the notification unit 125 first determines the cause of the colorimetric error based on the number of color patches that have become error patches in the test chart (S160). Specifically, when the number of error patches whose color difference ΔC exceeds the above-described preset color difference threshold is a part of the test chart, a colorimetric error (measurement target color) due to an external factor of the system. (S170), and if error patches are spread over a wide area of the test chart, a color measurement error (print unevenness, An abnormality or deterioration of the colorimeter is notified (S180). By performing the notification, the user is supported in grasping the cause of the colorimetric error. In the latter case, the operator performing color measurement may have made a mistake in the color measurement method. The possibility of performing colorimetry by the color method may be notified.

  Specifically, the determination of whether the number of error patches is a part of the test chart or a wide range is made, for example, when the average color difference of each color patch of the test chart does not exceed the preset color difference threshold described above. , It is determined that an error patch exceeding a preset color difference threshold has occurred in a part of the test chart, and the average color difference of each color patch of the test chart is equal to the previously set color difference. When the threshold value is exceeded, it can be determined that an error patch exceeding the preset color difference threshold value has occurred in a wide range of the test chart.

  When a color measurement error due to an internal factor is notified (S180), the color measurement error determination unit 123 records the type of the color measurement error notified to the color difference history database DB2 (S190), and reprints / re-colors the test chart. It is determined whether or not there is an error patch (S110 to S150). The test chart printed at this time is the same as the position printed at the time when a colorimetric error is found, as in the case of reprinting and re-coloring the reference chart with the reference data described above. You may print in a different position. Of course, only error patches may be printed, or all other patches may be printed. In this way, when reprinting and colorimetry is performed, the chart on which only the error patch is printed constitutes the second chart in detecting the colorimetric error, and the error patch is found to have a colorimetric error. A chart that is printed at a position different from the position that was sometimes printed constitutes a third chart in detecting a colorimetric error.

  After notifying a colorimetric error due to an external factor (S170), the colorimetry error determining unit 123 displays a UI screen for automatically removing or manually removing data relating to a color patch that is equal to or greater than the threshold (S200). . FIG. 12 is a diagram illustrating an example of a UI screen for performing manual removal. In the UI screen shown in the figure, the position of the error patch, the color of the ink used for printing the error patch, the gradation of the ink amount, and the deviation from the reference value of the colorimetric value (the above-described color difference) are displayed. Yes. In addition, the UI screen can select whether error patches are removed and complemented, or error patches are reprinted and re-measured, and the user can consider the information displayed on the UI screen. Then, one of the error patch removal is selected.

When automatic removal is performed (S200: Yes), or when the user selects error patch removal on the manual removal UI screen (S200: Yes), the colorimetric values relating to the error patch are deleted, and the ink amount scale The colorimetric values calculated by the interpolation calculation using the colorimetric values obtained by the colorimetry of adjacent color patches in the tone are complemented as the colorimetric values of the error patch (S210). Of course, the color difference value related to the error patch is calculated by interpolating the color difference related to the error patch from the color difference calculated in step S120 with respect to the color measurement value of the adjacent color patch in the ink amount gradation. May be supplemented.
On the other hand, when automatic removal is not performed (S200: No), or when the user selects reprinting and re-measurement of an error patch (S200: No), step S60 ′ in creating the reference data described above (FIG. 10). In the same manner as when a color measurement error due to an internal factor is notified (S180), the color patch that has become an error patch is reprinted / re-colored and the presence / absence of an error patch is determined (S100 to S150).

  When error patch complementation is completed (S210), processing related to notification based on the increasing tendency of the color difference is performed (S220 to S250). First, the colorimetric error determination unit 123 refers to the color difference history database DB2 and determines whether or not the color difference ΔC is increasing (S220). This tendency can be determined by performing various types of known prediction analysis such as regression analysis on the data in which the color difference history database DB2 is arranged in the registration order. If it is determined that the color difference tends to increase, the user is notified of the calibration time of the printing device 20 and the colorimetric device 30 to the notification unit 125 (S230).

  On the other hand, if it is determined that the color difference ΔC does not tend to increase, the host device 10 determines whether there is a difference in the variation tendency of the color difference ΔC between the color difference applied to the color patch of the specific ink color and the color patch of the other ink color. Judgment is made (S240). If there is a difference in the variation tendency, the user is notified that there is a possibility of ejection failure in the ink of a specific ink color (S250). When there is no difference in the variation tendency or when the notification in steps S230 and S250 is completed, the history database creation unit 124 records information such as the color difference ΔC in the color difference history database DB2 (S270), and the notification unit 125 performs the test. The color measurement result of the chart is displayed on the screen of the host device 10 (S280), and the process related to the detection of the color measurement error is finished.

  As described above, according to the detection of the color measurement mistake according to the present embodiment, the color patch 30 in the reference state is the inspection target color patch provided on the reference chart printed by the printing apparatus 20 in the reference state. Is used to acquire the specific spectral reflectance, and an abnormality related to printing or colorimetry of the color patch to be inspected is detected based on the color difference from the specific spectral reflectance of another color patch adjacent in the ink amount gradation. Therefore, notification of color measurement mistakes at the time of reference data creation is detected with high accuracy and high speed, the accuracy of reference data creation is improved, and color measurement mistakes are notified when a test chart color measurement error is found. As a result, it is possible to support the investigation of the cause of the colorimetric error and to prevent the colorimetric error.

(4) Modification:
(4-1) Modification 1:
In the embodiment described above, the case where the printing device 20 and the color measurement device 30 are separate has been described as an example. However, the printing device 20 and the color measurement device 30 may be integrated, or the printing device 20 may be integrated. It is good also as a structure arrange | positioned with the color measurement apparatus 30 immediately after. With such a configuration, while the printing device 20 is printing on the printing medium, the color measuring device 30 performs the printing of the printing medium at the same time as the printing of the printing device 20 on the print completion portion of the printing medium. Colorimetry may be executed. According to this configuration, for example, every time the main scanning for colorimetry of the colorimetry device 30 is completed for one pass, the presence or absence of an error patch is displayed on a predetermined display unit so that the user can check the error patch. If reprinting / re-coloring is selected, the error patch is applied to an area where no other color patch is printed at the end of the data of the chart being printed by the printing apparatus 20 (the above-mentioned reference chart, test chart, etc.). It is also possible to insert the determined patch and complete the reprinting / remeasurement by changing the position of the error patch on the one print medium.

(4-2) Modification 2:
In the above-described embodiment, the colorimetric error is detected using the spectral reflectance in the creation of the reference data and the detection of the colorimetric error. Of course, the colorimetric values such as L ^* a ^* b ^* are used. It can also be used.

(4-3) Modification 3:
In the above-described embodiment, the description has been given by taking the printing apparatus that performs printing by discharging ink as an example. However, the printing apparatus to which the present invention can be applied includes a liquid discharge head that ejects (discharges) a minute amount of liquid droplets, A device that ejects fluid other than ink, such as a liquid ejection device including The liquid droplet includes a granular liquid ejected by the liquid ejection device, a tear-like liquid, a liquid having a tail in a string shape, and the like. The liquid may be any material that can be discharged by the liquid discharge device. For example, a liquid, a sol, gel water, an inorganic solvent, an organic solvent, a solution, a liquid resin, a fluid such as a liquid metal (metal melt), Liquid phase substances such as The fluid is preferably a non-gaseous fluid, but may be a granular material such as toner. In addition to liquid phase substances, liquids include those obtained by dissolving, dispersing, or mixing particles of functional materials made of solid materials such as pigments and metal particles in a solvent. Ink, liquid crystal, and the like are typical examples of liquids. The ink includes general water-based ink and oil-based ink, and various liquid compositions such as gel ink and hot melt ink. Examples of the liquid ejection device include a device for ejecting a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, or a color filter in a dispersed or dissolved state. Is included. In addition, the liquid ejection device is a device that ejects biological organic materials used in biochip manufacturing, a device that ejects liquid as a sample used as a precision pipette, a textile printing device, a microdispenser, a clock or a camera. In order to etch a substrate, a device for discharging a transparent resin liquid such as an ultraviolet curable resin to form a device for discharging lubricating oil, a micro hemispherical lens (optical lens) used for an optical communication element, etc. An apparatus for discharging an etching solution such as acid or alkali is included.

(4-4) Modification 4:
In the present invention, at the manufacturing stage of the printing apparatus 20 constituting the printing system S1 shown in FIG. 1A, the above-described printing apparatus 20 is used to print the reference chart, measure the color, detect an error patch, and the like. Accordingly, the case where the reference patch database DB1 is created under the control of the host device 10 is naturally included.
Further, in the manufacturing stage of the printing apparatus 20 constituting the printing system S1 shown in FIG. 1B, by using the printing apparatus 20, the above-described reference chart printing, color measurement, error patch detection, and the like are performed. The reference patch database DB1 is created under the control of the printing apparatus 20 or the color measurement apparatus 30, and the created reference patch database DB1 is stored in the storage medium of the printing apparatus 20 or the color measurement apparatus 30. Within range.
Of course, in the manufacturing stage of the printing apparatus 20 constituting the printing system S1 shown in FIG. 1A, the above-described printing apparatus 20 is used to perform the above-described printing of the reference chart, color measurement, error patch detection, and the like. It is also within the scope of the present invention to create the reference patch database DB1 under the control of the host device 10 and store the created reference patch database DB1 in the storage medium of the printing device 20 or the color measurement device 30.
In addition, calibration for adjusting the ink discharge amount of the printing apparatus 20 while detecting the above-described colorimetric error using the reference patch database DB1 is naturally within the scope of the present invention.

(4-5) Modification 5:
In the above-described embodiment, the program execution entity is mainly the host device 10, but the program execution entity is not limited to that described above, and is between the host device 10, the printing device 20, and the color measurement device 30. As appropriate, it can be shared and executed. That is, the above-described reference data creation and colorimetric error detection may be performed with the printing apparatus 20 as the execution subject, or the above-described reference data creation and colorimetry mistake with the colorimetry device 30 as the execution subject. The above-described reference data creation and colorimetric error detection may be performed while executing a part of the program in any combination of the host device 10, the printing device 20, and the colorimetric device 30. May be.

  Note that the present invention is not limited to the above-described embodiments and modifications, and the structures disclosed in the above-described embodiments and modifications are mutually replaced, the combinations are changed, the known technique, and the above-described implementations. Configurations in which the configurations disclosed in the embodiments and modifications are mutually replaced or the combinations are changed are also included.

DESCRIPTION OF SYMBOLS 10 ... Host apparatus, 20 ... Printing apparatus, 30 ... Colorimetry apparatus, 100 ... Computer, 101 ... CPU, 102 ... RAM, 103 ... Hard disk, 110 ... Reference patch database creation module, 111 ... Reference chart printing part, 112 ... Measurement Color data acquisition unit 113 ... Color measurement error determination unit 114 ... Database creation unit 120 ... Color measurement error detection module 121 ... Test chart printing unit 122 ... Color measurement data acquisition unit 123 ... Color measurement error determination unit 124 ... history database creation unit, 125 ... notification unit, BC ... reference chart, DB1 ... reference patch database, DB2 ... color difference history database, I S _... ink amount gradation, C01～C16 ... color patches, M01～M16 ... color patches , Y01 to Y16 ... color patches, K01 to K16 ... color patches, x ... inspection target color patches, Px + 1 ... color patch, Px-1 ... color patch, S1 ... printing system, S2 ... printing system

Claims (8)

A print control method for printing a chart provided with a color patch on a printing unit and detecting an abnormality related to printing or color measurement of the color patch based on a color measurement result of the color patch by a color measurement unit,
Using the colorimetric unit, obtain a spectral reflectance of a predetermined wavelength of the color patch provided in the first chart printed by the printing unit,
Spectral reflectance of the predetermined wavelength of the color patch and a predetermined wavelength acquired by using the colorimetric unit for the other color patches provided in the first chart adjacent to the color patch in the ink amount gradation Detecting an abnormality in the color patch printing or color measurement based on the color difference between the spectral reflectance and
The predetermined wavelength is any wavelength from 400 nm to 600 nm for a color patch relating to a cyan color material, and any wavelength other than 430 nm to 560 nm for a color patch relating to a magenta color material. The print control method according to claim 1, wherein the color patch is any wavelength excluding 380 nm to 470 nm, and the color patch relating to the black color material is any wavelength except 380 nm to 470 nm. The abnormality is detected for a plurality of color patches provided in the first chart,
Causing the printing unit to print a second chart provided with only the color patch in which the abnormality is detected;
Using the colorimetric unit for the color patches provided in the second chart, the spectral reflectance at the predetermined wavelength is acquired,
Spectral reflectance of the predetermined wavelength of the color patch provided in the second chart and other provided in the first chart adjacent to the color patch provided in the second chart in the ink amount gradation Based on the color difference between the color patch and the spectral reflectance at a predetermined wavelength acquired using the colorimetric unit, an abnormality related to printing or colorimetry of the color patch provided in the second chart is detected. The printing control method according to claim 1. The abnormality is detected for a plurality of color patches provided in the first chart,
A third chart in which only the color patch in which the abnormality is detected is provided at a printing position different from that in which the abnormality is detected is printed on the printing unit,
Using the colorimetric unit for the color patch provided in the third chart, the spectral reflectance at the predetermined wavelength is acquired,
The spectral reflectance of the predetermined wavelength of the color patch provided in the third chart and the first chart or the third adjacent to the color patch provided in the third chart in the ink amount gradation Based on the color difference between the other color patches provided on the chart and the spectral reflectance at a predetermined wavelength obtained by using the colorimetric unit, the printing or measurement of the color patches provided on the third chart is performed. The print control method according to claim 1, wherein an abnormality relating to a color is detected.   Complementing the colorimetric result of the color patch in which the abnormality is detected by interpolation using the colorimetric results of a plurality of other color patches printed with a color material amount different from the color patch in which the abnormality is detected, The color material amount of the color patch in which the abnormality is detected and the complemented color measurement result are stored in association with each other in a predetermined storage medium. The printing control method as described. Detecting the abnormality for each of a plurality of color patches printed on one print medium;
When at least one of the plurality of color patches has an error in the color difference that exceeds a predetermined value and an average of the error in the color difference of the plurality of color patches does not exceed the predetermined value, an abnormality in colorimetry due to an external factor The print control method according to any one of claims 1 to 4, wherein the user is notified. Detecting the abnormality for each of a plurality of color patches printed on one print medium;
When at least one of the plurality of color patches has an error of the color difference exceeding a predetermined value and an average of the error of the color difference of the plurality of color patches exceeds the predetermined value, color measurement abnormality due to an internal factor is detected. The printing control method according to claim 1, which notifies a user.   The color difference of the color patch is recorded as a history, and when the color difference gradually increases in the history, the user is notified of the calibration time of at least one of the printing unit and the colorimetric unit. 7. The printing control method according to any one of items 6.   History of the color difference of the color patch, and in the history, when the variation tendency of the color difference applied to the color patch of a specific color material is different from the variation tendency of the color difference applied to the color patch of another color material, the printing unit The printing control method according to any one of claims 1 to 7, wherein a user is notified of an abnormality in the amount of the specific color material to be adhered to the print medium.