JP4919151B2 - Control apparatus, image forming apparatus, and program - Google Patents

Description

The present invention relates to a control device, an image forming apparatus, a 及 beauty program.

For example, Patent Document 1 discloses a test image of a check pattern in which continuous areas where gradations increase in stages and reference areas are alternately arranged.
Further, Patent Document 2 discloses that a gradation pattern of 16 gradations is created for each color, and 16 uniform patterns are created at the left adjacent portions thereof.
JP 2002-044455 A JP 2001-088357 A

  The present invention has been made from the above-described background, and an object thereof is to improve the accuracy of calibration.

  In order to achieve the above object, according to the first aspect of the present invention, a set of a plurality of image elements associated with a reference density value is arranged in a first image area, and the outside of the first image area. Image generating means for generating image information in which an image element of the reference density value is arranged in a second image area; and image providing means for providing the image information generated by the image generating means to an image forming apparatus. Have

  In the present invention according to claim 2, a set of image elements associated with a plurality of colors and a plurality of reference density values is arranged in the first image region of the image information.

  In the present invention according to claim 3, image elements of a plurality of colors and a plurality of reference density values are arranged in the second image region of the image information, and each of the image elements of the reference density value is the image. When the recording medium on which information is formed is folded, the recording medium is arranged at a position adjacent to the image element of the first image area associated with each of these reference density values.

  In the present invention according to claim 4, the image element arranged in the first image area of the image information is a halftone dot of a predetermined period, and each of the plurality of density values associated with the reference density value is represented by an area scale. The image element arranged in the second image area of the image information is a halftone dot having a period longer than that of the image element arranged in the first image area. It is an image expressed in area gradation.

  In the present invention according to claim 5, the image element arranged in the first image area of the image information is an image generated by area gradation processing used when the image forming apparatus forms other image information. The image element arranged in the second image area of the image information is an image generated by area gradation processing different from that of the image element arranged in the first image area.

In the present invention according to claim 6, the image information includes a folding position between an image element arranged in the first image area and an image element in a second image area corresponding to the image element. The mark which shows is arranged.
In the present invention according to claim 7, the image element having the reference density value arranged in the second image area has substantially the same size as the area occupied by the plurality of image elements associated with the reference density value. .

  According to the eighth aspect of the present invention, in the first image area, an image element in which the reference density value is expressed by area gradation with a halftone dot having a predetermined area is arranged, and the first image area is outside the first image area. Image generating means for generating image information in which an image element in which the reference density value is expressed by area gradation with a halftone dot having a larger area than the image element of the first image area is arranged in the second image area; Image providing means for providing the image forming apparatus with the image information generated by the image generating means.

  The present invention according to claim 9 further includes position determining means for determining a position of the first image area in accordance with uniformity of output density by the image forming apparatus, wherein the image generating means Image information in which the first image region is provided at the position determined by the determining unit is generated.

  In the present invention according to claim 10, the image generation means generates image information in which the first image region is provided at a central portion of the entire image.

  According to the eleventh aspect of the present invention, an image element in which a reference density value is expressed by area gradation with a halftone dot having a predetermined area is arranged in the image forming means and the first image region. A test image in which an image element in which the reference density value is expressed by area gradation with a halftone dot having a larger area than the image element of the first image area is arranged in a second image area outside the image area. Control means for forming the forming means.

  In the twelfth aspect of the present invention, the control unit forms the image element of the first image region in a region where the output density of the image forming unit is higher than that of the second image region.

  According to the thirteenth aspect of the present invention, a set of a plurality of image elements associated with the reference density value is disposed in the image forming apparatus and the first image area, and the second image element is located outside the first image area. And a control device that causes the image forming apparatus to form image information in which the image element having the reference density value is arranged in the image area.

  According to the fourteenth aspect of the present invention, a set of a plurality of image elements associated with the reference density value is arranged in the first image region, and the second image region outside the first image region is Image information in which the image element of the reference density value is arranged is formed in an image forming apparatus, and the image element of the formed first image area is compared with the image element of the formed second image area; Based on the comparison result, the output density of the image forming apparatus is adjusted.

  According to the fifteenth aspect of the present invention, in the first image region, a set of a plurality of image elements associated with the reference density value is arranged, and in the second image region outside the first image region, A computer is caused to generate image information in which image elements having the reference density value are arranged, and to provide the generated image information to an image forming apparatus.

According to the first aspect of the invention, there is an effect that it is possible to suppress the influence of density unevenness on a plurality of image elements associated with the reference density value.
According to the second aspect of the invention, there is an effect that it is possible to suppress the influence of density unevenness on a plurality of image elements associated with a plurality of colors and a plurality of reference density values.
According to the third aspect of the present invention, there is an effect that it is possible to easily compare the image element arranged in the first image area and the image element arranged in the second image area.
According to the invention which concerns on Claim 4, there exists an effect that the influence of the density nonuniformity with respect to the image element arrange | positioned in the 2nd image area can be suppressed.
According to the invention concerning Claim 5, there exists an effect that the output density at the time of printing other image data can be evaluated in a 1st image area.
According to the invention of claim 6, there is an effect that the user can compare the image elements close to each other.
According to the invention concerning Claim 7, there exists an effect that a user can compare an image element easily.
According to the invention which concerns on Claim 8, there exists an effect that the image element which is easy to be influenced by the density nonuniformity can be arrange | positioned collectively.
According to the ninth aspect of the invention, there is an effect that a test image can be generated according to the uniformity of the output density by the image forming apparatus.
According to the tenth aspect of the present invention, there is an effect that it is possible to arrange an image element that is easily affected by density unevenness in an image central portion where density unevenness is less likely to occur than at the peripheral edge.
According to the invention of claim 11, there is an effect that image elements that are easily affected by density unevenness can be arranged together.
According to the twelfth aspect of the present invention, there is an effect that image elements having different characteristics with respect to density unevenness can be arranged in consideration of uniformity of output density.
According to the thirteenth aspect of the invention, there is an effect that image elements that are easily affected by density unevenness can be arranged together.
According to the fourteenth aspect of the invention, there is an effect that the influence of density unevenness on the output density calibration process can be suppressed.
According to the fifteenth aspect of the present invention, there is an effect that image elements that are easily affected by density unevenness can be arranged together.

First, the configuration of the printer 10 will be described.
FIG. 1 is a diagram illustrating a configuration of a tandem printer 10.
As shown in FIG. 1, the printer 10 includes a control device 12, a communication device 13, an image forming unit 14, an intermediate transfer belt 16, a paper tray 17, a paper conveyance path 18, and a fixing device 19.
The printer 10 of this example has only a printer function for printing image data received from a computer terminal (not shown), but is not limited to this, and functions as a scanner, a function as a copying machine, Further, it may further have a function as a facsimile.

First, the outline of the printer 10 will be described. A control device 12 and a communication device 13 are arranged on the upper portion of the printer 10. The control device 12 is a controller provided with an arithmetic device, a memory, an ASIC, and the like, and controls other configurations of the printer 10. The communication device 13 communicates with a computer terminal (not shown) via a network.
Below the control device 12, a plurality of image forming units 14 are arranged corresponding to the colors constituting the color image. In this example, the first image forming unit 14K, the second image forming unit 14Y, and the third image forming corresponding to each color of black (K), yellow (Y), magenta (M), and cyan (C). The unit 14M and the fourth image forming unit 14C are arranged horizontally along the intermediate transfer belt 16 with a certain interval. The intermediate transfer belt 16 rotates as an intermediate transfer member in the direction of the arrow A in the figure, and these four image forming units 14K, 14Y, 14M, and 14C have different colors based on the image data input from the control device 12. Toner images are sequentially formed, and transferred (primary transfer) to the intermediate transfer belt 16 at a timing at which the plurality of toner images are superimposed on each other. The order of the colors of the image forming units 14K, 14Y, 14M, and 14C is not limited to the order of black (K), yellow (Y), magenta (M), and cyan (C). ), Magenta (M), cyan (C), black (K), and the like.

  The sheet conveyance path 18 is disposed below the intermediate transfer belt 16. The recording paper supplied from the paper tray 17 is transported on the paper transport path 18, and the toner images of each color transferred onto the intermediate transfer belt 16 are collectively transferred (secondary transfer). The toner image thus fixed is fixed by the fixing device 19 and discharged to the outside along the arrow B.

Next, each configuration of the printer 10 will be described in more detail.
As shown in FIG. 1, when the control device 12 receives image data from a computer terminal via the communication device 13, the control device 12 performs color conversion processing, density correction processing, halftone processing, and the like on the received image data. To the image forming unit 14.
In addition, the control device 12 generates test image data used for calibration as necessary, and outputs the generated test image data to the image forming unit 14.

The first image forming unit 14K, the second image forming unit 14Y, the third image forming unit 14M, and the fourth image forming unit 14C are arranged and formed in parallel at a certain interval in the horizontal direction. The configuration is almost the same except that the color of the image is different. Accordingly, the first image forming unit 14K will be described below. The configuration of each image forming unit 14 is distinguished by adding K, Y, M, or C.
The image forming unit 14K includes an optical scanning device 140K that scans laser light in accordance with image data input from the control device 12, and an image in which an electrostatic latent image is formed by the laser light scanned by the optical scanning device 140K. And a forming apparatus 150K.

The optical scanning device 140K modulates the semiconductor laser 142K according to the black (K) image data, and emits the laser light LB (K) from the semiconductor laser 142K according to the image data. The laser beam LB (K) emitted from the semiconductor laser 142K is applied to the rotary polygon mirror 146K via the first reflection mirror 143K and the second reflection mirror 144K, and is deflected and scanned by the rotation polygon mirror 146K. The light is irradiated onto the photosensitive drum 152K of the image forming apparatus 150K through the second reflecting mirror 144K, the third reflecting mirror 148K, and the fourth reflecting mirror 149K.
The image forming apparatus 150K includes a photosensitive drum 152K as an image carrier that rotates at a predetermined rotational speed in the direction of arrow A, and primary charging as a charging unit that uniformly charges the surface of the photosensitive drum 152K. And a developing device 156K for developing the electrostatic latent image formed on the photosensitive drum 152K, and a cleaning device 158K. The photosensitive drum 152K is uniformly charged by the scorotron 154K, and an electrostatic latent image is formed by the laser beam LB (K) irradiated by the optical scanning device 140K. The electrostatic latent image formed on the photosensitive drum 152K is developed with black (K) toner by the developing device 156K and transferred to the intermediate transfer belt 16. Residual toner, paper dust, and the like adhering to the photosensitive drum 152K after the toner image transfer process are removed by the cleaning device 158K.
The other image forming units 14Y, 14M, and 14C also form yellow (Y), magenta (M), and cyan (C) toner images in the same manner as described above, and intermediately transfer the formed toner images of the respective colors. Transfer to belt 16.

The intermediate transfer belt 16 has a constant tension between the drive roll 164, the first idle roll 165, the steering roll 166, the second idle roll 167, the backup roll 168, and the third idle roll 169. The drive roll 164 is rotationally driven by a drive motor (not shown), and is circulated at a predetermined speed in the direction of arrow A. The intermediate transfer belt 16 is formed into an endless belt by, for example, forming a flexible synthetic resin film such as polyimide in a belt shape and connecting both ends of the synthetic resin film formed in a belt shape by welding or the like. It has been done.
Further, the intermediate transfer belt 16 includes a first primary transfer roll 162K, a second primary transfer roll 162Y, a third primary transfer roll 162M, and a position facing the image forming units 14K, 14Y, 14M, and 14C, respectively. A fourth primary transfer roll 162C is provided, and the toner images of the respective colors formed on the photosensitive drums 152K, 152Y, 152M, and 152C are transferred onto the intermediate transfer belt 16 in a multiple manner by these primary transfer rolls 162. The The residual toner adhering to the intermediate transfer belt 16 is removed by a cleaning blade or brush of a belt cleaning device 189 provided downstream of the secondary transfer position.

In the paper transport path 18, a paper feed roller 181 for taking out the recording paper from the paper tray 17, a first roller pair 182 and a second roller pair 183 for paper transport, and a secondary transfer of the recording paper at a predetermined timing. A resist roll 184 that is transported to a position is disposed.
In addition, a secondary transfer roll 185 that is in pressure contact with the backup roll 168 is disposed at the secondary transfer position on the paper transport path 18, and each color toner image transferred onto the intermediate transfer belt 16 is Secondary transfer is performed on the recording paper by the pressing force and electrostatic force of the secondary transfer roll 185. The recording paper on which the toner images of the respective colors are transferred is conveyed to the fixing device 19 by the first conveying belt 186 and the second conveying belt 187.
The fixing device 19 melts and fixes the toner to the recording paper by performing heat treatment and pressure treatment on the recording paper on which the toner images of the respective colors are transferred.

Next, a program installed in the control device 12 will be described.
FIG. 2 is a diagram for explaining the functional configuration of a program executed by the control device 12 (FIG. 1) with a focus on the calibration control unit 50.
As illustrated in FIG. 2, the control device 12 includes a calibration control unit 50 that performs output density calibration, a color conversion unit 60 that performs color conversion of image data, and a density correction unit 62 that performs density correction of image data. In addition, an area gradation processing unit 64 that performs halftone processing and a printing unit 66 that performs printing processing by controlling the image forming unit 14 and the like are installed.
The calibration control unit 50 includes a user interface unit (UI unit) 500, a data generation unit 510, a data providing unit 520, a correction value selection unit 530, a test image recording unit 540, and a correction value database (correction value DB) 550. Have
Note that a program installed in the control device 12 (for example, a program corresponding to the calibration control unit 50) may be recorded on a recording medium such as a CD-ROM and installed in the control device 12 via this recording medium. However, it may be distributed in the form of a data signal and installed in the control device 12. In this example, the entire functional configuration of the program such as the calibration control unit 50 is installed in the control device 12 as software. However, the present invention is not limited to this. For example, a part of the program is a hardware such as an ASIC. It may be realized by hardware.

In the calibration control unit 50, the UI unit 500 controls a touch panel (not shown) or a computer terminal (not shown) of the printer 10 and receives an instruction from the user.
The UI unit 500 of this example receives an instruction regarding calibration processing from a user, and outputs the user instruction to the data generation unit 510 or the correction value selection unit 530. For example, when the user instructs the start of the calibration process, the UI unit 500 outputs that fact to the data generation unit 510, and when the user inputs a patch identification number, the input patch identification number is input to the correction value selection unit. Output to 530.

The data generation unit 510 generates test image data used for the calibration process, and outputs the generated test image data to the data providing unit 520. In the test image data, a set of a plurality of image elements associated with the reference density value is arranged in the first image area, and the reference density value is set in the second image area outside the first image area. The image data in which the image elements are arranged. The plurality of image elements associated with the reference density value are, for example, compared with the image element of the reference density value in the calibration. In this example, the density is stepwise in the density range near the reference density value. This is a solid image element whose value is changed.
The data generation unit 510 of this example reads binary test image data recorded in the test image recording unit 540 and outputs the read test image data to the data providing unit 520. In this example, test image data (binary) is prepared in advance in the test image recording unit 540, and the data generation unit 510 simply reads out test image data prepared in the test image recording unit 540. However, the present invention is not limited to this. For example, multi-value or binary test image data may be generated by halftoning each of the image elements (multi-value) of the test image prepared in advance. .

The data providing unit 520 outputs the image data generated by the data generating unit 510 to the image forming unit 14 to form a test image.
The data providing unit 520 of this example causes the image forming unit 14 to form a test image 9 (described later in FIG. 3) as a test image.

The correction value selection unit 530 selects and selects the correction information for correcting the output density from the correction information recorded in the correction value DB 550 according to the patch identification number selected by the user. The correction information is output to the density correction unit 62.
The correction value selection unit 530 of this example reads out the correction amount for correcting the γ correction curve of each color from the correction value DB 550 according to the patch identification number input from the UI unit 500, and reads the correction amount of each read color Is output to the density correction unit 62. The density correction unit 62 updates the γ correction curve based on the correction amount input from the correction value selection unit 530, and corrects the density value of each color with the updated γ correction curve.

The test image recording unit 540 records test image data.
In the test image recording unit 540 of the present example, an image element in which a reference density value is expressed by area gradation with a halftone dot of a predetermined size is arranged in a first image area, and a second image area outside the first image area. In this image area, image data in which an image element in which the reference density value is expressed by area gradation with a halftone dot larger than the image element of the first image area is arranged is recorded as test image data. The halftone dots of the image elements arranged in the first image area are preferably halftone dots used in normal printing processing other than the calibration processing (that is, halftone dots used by the area gradation processing unit 64).

The correction value DB 550 records the density correction amount of each color and each density area in association with the identification number of each color and each density area patch.
The correction value DB 550 of this example records a correction amount that cancels out the density fluctuation (that is, the fluctuation amount from the reference density value) in each color and each density area in association with the identification number of each color and each density area patch. ing.

FIG. 3 is a diagram illustrating a test image 9 generated by the data generation unit 510.
As illustrated in FIG. 3, the test image 9 is provided with an adjustment patch region 900 (first image region) and a reference patch region 910 (second image region). The adjustment patch area 900 is a closed area and does not include all or part of the reference patch area 910. In this example, the adjustment patch area 900 is gathered at the center of the image area, and the reference patch area 910 is arranged around the adjustment patch area 900.

In the adjustment patch area 900, a plurality of adjustment patches 902 associated with the reference density value are provided. The adjustment patches 902 associated with the reference density values of the respective colors are continuously arranged as an adjustment patch set and collected in one place. In this example, three reference density values are set for each color, and three gradation patch sets associated with these reference density values are provided.
Each adjustment patch 902 is an image element filled with a single density value included in a density range in the vicinity of the reference density value, and is composed of halftone dots used in normal printing processing.

  The reference patch area 910 is provided with a plurality of reference patches 912 filled with the standard density value. In this example, one reference patch 912 has a size corresponding to the adjustment patch set (for five adjustment patches). The reference patch 912 includes halftone dots having a longer period than the adjustment patch 902. That is, when comparing with the same color and the same density value, the halftone dots constituting the reference patch 912 are larger than the halftone dots constituting the adjustment patch 902. The halftone dots constituting the reference patch 912 are halftone dots (in other words, line dots) having a longer cycle than any halftone dots used in normal printing processing (that is, halftone dots used by the area gradation processing unit 64). It is preferable that the number of dots is small.

Further, as illustrated in FIG. 3, the test image 9 is provided with a valley fold mark 932 and a mountain fold mark 934.
The valley fold mark 932 and the mountain fold mark 934 are arranged between the adjustment patch 902 and the reference patch 912, and indicate the bending position of the recording paper to the user. For example, between the C color adjustment patches 902C1 to 902C15 and the C color reference patches 912C1 to 912C3, as a mark indicating the folding position when the C color is compared, a valley fold line 932CY and a mountain fold mark 934C is provided between the Y color adjustment patches 902Y1 to 902Y15 and the Y color reference patches 912Y1 to 912Y3 as a mark indicating the folding position when the Y color is compared. 932CY and a mountain fold mark 934Y are provided. The valley fold mark 932 in this example substantially coincides with the vertical bisector of the adjustment patch 902 and the corresponding reference patch 912, and the mountain fold mark 934 is a valley disposed near the reference patch 912. This is a line parallel to the fold mark 932 (dashed line).

  When the user bends the recording paper on which the test image 9 is printed in accordance with the instructions of the valley fold mark 932 and the mountain fold mark 934, as shown in FIG. 4, the adjustment patches 902 for each color correspond to the corresponding reference. It is in a position adjacent to the patch 912. In this way, the user compares the reference patch 912 filled with the reference density value with the adjustment patch set associated with the reference density value, and sets the identification number of the adjustment patch with the closest density to the UI device or the like. input. In this example, three reference density values (for example, a reference density value in a low density area, a reference density value in a middle density area, and a reference density value in a high density area) are set for each color. For each color, three adjustment patch identification numbers are entered.

Next, the overall operation of the density calibration process will be described.
FIG. 5 is a flowchart for explaining the overall operation (S10) of the density configuration process.
As shown in FIG. 5, in step 100 (S100), when the user operates the touch panel (not shown) of the printer 10 to instruct the start of the density calibration process, the UI unit 500 (FIG. 2) of the control device 12 is displayed. Detects this user operation and instructs the data generation unit 510 to print a test image.
The data generation unit 510 reads the image data of the test image 9 (FIG. 4) recorded in the test image recording unit 540 and outputs the read data (binary data) of the test image 9 to the data providing unit 520. To do.

In step 110 (S110), the data providing unit 520 (FIG. 4) controls the image forming unit 14 (FIG. 1) and the like to print the image data of the test image 9 input from the data generating unit 510 on the recording paper. Let
The user folds the recording sheet on which the test image 9 is printed according to the valley fold mark 932 and the mountain fold mark 934 corresponding to each color as illustrated in FIG. Thereby, the reference patch 912 and the adjustment patch 902 of each color are adjacent to each other.
Then, the user visually compares the reference patch and the adjustment patch, and selects the reference patch having the closest density for each of the three standard density values.

In step 120 (S120), the user operates the touch panel (not shown) of the printer 10 and sequentially inputs the identification numbers (numbers “1” to “15” in FIG. 4) of the selected three reference patches. .
The UI unit 500 (FIG. 2) outputs the identification number input by the user to the correction value selection unit 530.

In step 130 (S130), the calibration control unit 50 determines whether or not identification numbers have been input for all the colors. If there are unidentified identification numbers, the calibration control unit 50 notifies the user to that effect, When the identification number is input, the process proceeds to S140.
If there is an uninput identification number, the user returns to the processing of S120 and bends the recording sheet on which the test image 9 is printed according to the valley fold mark 932 and the mountain fold mark 934 corresponding to the uninput color. .

  In step 140 (S140), the correction value selection unit 540 determines whether or not the γ correction curve needs to be updated based on the input identification number. In this example, the density value of the center adjustment patch in each of the adjustment patch sets in FIG. 3 is the same as the reference density value. ) Is selected, there is no need to update the γ correction curve.

  If the calibration control unit 50 determines that it is not necessary to update the gamma correction curve for all colors, it ends the calibration process (S10), and it is necessary to update the γ correction curve for any color. If it is determined, the process proceeds to S150 and subsequent steps for colors that need to be updated.

  In step 150 (S150), the correction value selection unit 540 reads the correction amount corresponding to the adjustment patch identification number from the correction value DB 550, and outputs the read correction amount to the density correction unit 62.

In step 160 (S160), the density correction unit 62 updates the γ correction curve based on the correction amount input from the correction value selection unit 540.
Since the density correction unit 62 of this example implements γ correction using a lookup table, the lookup table for each color is updated according to the correction amounts in the three density regions.

[Modification]
Next, a modification of the above embodiment will be described.
FIG. 6 is a diagram illustrating density unevenness (in-plane unevenness) occurring in the same image. Note that the image and density exemplified in this figure are obtained by printing solid image data with a single density value.
As illustrated in FIG. 6A, depending on the printer, the output density may change monotonously or monotonically depending on the position in the main scanning direction. Such density fluctuation is called left-right density unevenness.
As illustrated in FIG. 6B, the output density is substantially constant at the center position in the main scanning direction depending on the printer, but the output density may increase or decrease near both ends in the main scanning direction. is there. Such density fluctuation is called uneven density at both ends.

Since the adjustment patch 902 is composed of halftone dots having a larger number of lines than the reference patch 912 (ie, short-period halftone dots), the adjustment patch 902 is easily affected by in-plane unevenness.
Therefore, in this modification, in-plane unevenness of the printer is analyzed, and a test image in which the adjustment patch area 900 is provided in an area with less in-plane unevenness is printed on the printer according to the analysis result.

In the above embodiment, the test image data is generated by the control device 12 provided in the printer 10, but the present invention is not limited to this. For example, the test image data is generated outside the printer 10. The generated test image data may be printed on each printer 10.
Therefore, in the present modification, the print control server 40 (described later) analyzes the in-plane unevenness of each printer 10, generates test image data corresponding to the analysis result, and causes the printer 10 to print.

FIG. 7 is a diagram illustrating the overall configuration of the image forming system 1.
As illustrated in FIG. 7, the image forming system 1 includes a plurality of printers 10, a scanner 20, a computer terminal 30, and a print control server 40.
The plurality of printers 10, scanner 20, computer terminal 30, and print control server 40 are connected to each other via a network.
The printer 10 prints an image in response to a print request from the computer terminal 30.
The scanner 20 reads a test chart printed by the printer 10. The test chart is an image for analyzing in-plane unevenness, and is different from the test image 9 of FIG. For example, the test chart is an image in which the same density is arranged over the entire main scanning direction and the entire sub-scanning direction.
The print control server 40 is a print server. When a print request is received from the computer terminal 30, the print control server 40 controls the printer 10 according to the print request and causes the printer 10 to perform print processing. Further, the print control server 40 analyzes the in-plane unevenness generated in each printer 10 based on the test chart read by the scanner 20, generates image data of the test image according to the analysis result, and sends it to the printer 10. Let it print.

FIG. 8 is a diagram for explaining the functional configuration of a program executed by the print control server 40 (FIG. 7) with a focus on the calibration control unit 52. It should be noted that among the components shown in this figure, the same reference numerals are given to the components substantially the same as those shown in FIG.
As illustrated in FIG. 8, the print control server 40 includes a calibration control unit 52 that performs calibration of each printer 10, a color conversion unit 60 that performs color conversion of image data, and a density correction that performs density correction of image data. A unit 62, an area gradation processing unit 64 that performs halftone processing, and a printing unit 66 that controls each printer 10 to perform printing processing are installed.
As shown in FIG. 8, the second calibration control unit 52 replaces the test image recording unit 540 of the configuration control unit 50 of FIG. 2 with a test image database (test image DB) 542, and further, the uniformity evaluation unit 560. And the position determination part 570 is added.

In the calibration control unit 52, the uniformity evaluation unit 560 evaluates the uniformity of the image output from each printer 10.
The uniformity evaluation unit 560 of this example calculates an output density fluctuation amount with respect to a reference density value in the main scanning direction and the sub-scanning direction based on the test chart image data received from the scanner 20, and calculates the calculated main scanning. The fluctuation amount in the direction and the sub-scanning direction is output to the position determination unit 570.

The position determination unit 570 determines the position where the adjustment patch region 900 is arranged according to the uniformity (uniformity of output density of each printer) evaluated by the uniformity evaluation unit 560.
The position determination unit 570 in this example specifies and specifies an image region in which in-plane unevenness is equal to or less than a reference value based on the density fluctuation amount in the main scanning direction and the sub-scanning direction input from the uniformity evaluation unit 560. The range of the image area is output to the data generation unit 510.

The test image DB 542 stores test image data in association with output density uniformity.
As illustrated in FIG. 9, the test image DB 542 of this example records test image data in association with an image region in which in-plane unevenness is equal to or less than a reference value.

In the present modification, the data generation unit 510 generates test image data in which the adjustment patch region 900 is arranged at the position determined by the position determination unit 570.
The data generation unit 510 of the present modification selects a test image to be applied from the test image data recorded in the test image DB 542 based on the range of the image area where the in-plane unevenness is equal to or less than the reference value. Then, the data of the selected test image is output to the data providing unit 520.

[Other test images]
Next, a modified example of the test image will be described.
FIG. 10 is a diagram illustrating image data of the second test image 92.
As illustrated in FIG. 10, in the data generation unit 510, the adjustment patch for the standard density value is arranged in the adjustment patch area 900, and a plurality of reference patches associated with the standard density value are arranged in the reference patch area 910. The test image 92 may be generated.
Further, the data generation unit 510 may change the arrangement of the adjustment patch and the reference patch according to the uniformity of the output density of the printer. For example, when the output density uniformity in the sub-scanning direction of the printer 10 is higher than the uniformity in the main scanning direction, the data generation unit 510 arranges the adjustment patch and the reference patch longer in the sub-scanning direction, and performs main scanning. When the uniformity of output density in the direction is higher than the uniformity in the sub-scanning direction, the adjustment patch and the reference patch may be arranged longer in the main scanning direction.

1 is a diagram illustrating a configuration of a tandem type printer 10. FIG. It is a figure explaining the functional structure of the program performed by the control apparatus 12 (FIG. 1) centering on the calibration control part 50. FIG. It is a figure which illustrates test image 9 generated by data generation part 510. It is a figure which illustrates the aspect when the recording paper on which the test image 9 (FIG. 3) was printed is bent. It is a flowchart explaining the whole operation | movement (S10) of a density | concentration structure process. It is a figure which illustrates the density nonuniformity (in-plane nonuniformity) which arises in the same image. 1 is a diagram illustrating an overall configuration of an image forming system 1. FIG. It is a figure explaining the function structure of the program run by the printing control server 40 (FIG. 7) centering on the 2nd calibration control part 52. FIG. 5 is a diagram illustrating information recorded in a test image database 542. FIG. It is a figure which illustrates the 2nd test image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image forming system 10 ... Printer 12 ... Control apparatus 20 ... Scanner 30 ... Computer terminal 40 ... Print control server 50 ... Calibration control part 500 ... User interface part 510: Data generation unit 520 ... Data provision unit 530 ... Correction value selection unit 540 ... Test image recording unit 542 ... Test image database 550 ... Correction value database 9, 92 ... Test image 900 ... Adjustment patch area 902 ... Adjustment patch 910 ... Reference patch area 912 ... Reference patch 932 ... Valley fold mark 934 ... Mountain fold mark

Claims (6)

An evaluation means for calculating a fluctuation amount of the output density of the image forming apparatus with respect to a reference value;
Based on the fluctuation amount calculated by the evaluation means, a set of a plurality of image elements that are adjustment patches associated with the reference density value is arranged, and the position of the image area where the density unevenness in the plane is equal to or less than the reference value is determined. Position determining means for
Image generating means for generating image information in which the set of the plurality of image elements is arranged at the position determined by the position determining means;
A control device comprising: image providing means for providing image information generated by the image generating means to an image forming apparatus. When the output density uniformity in the sub-scanning direction is higher than the output density uniformity in the main scanning direction, the image elements in the image area are arranged to be longer in the sub-scanning direction than in the main scanning direction. The control device according to claim 1. The control device according to claim 1, wherein the image information includes a set of image elements associated with a plurality of colors and a plurality of reference density values. The control device according to claim 1, wherein the image generation unit generates image information in which a set of the plurality of image elements is arranged at a central portion of the entire image. An image forming means;
Evaluation means for calculating a variation amount of the output density of the image forming means with respect to a reference value;
Based on the fluctuation amount calculated by the evaluation means, a set of a plurality of image elements that are adjustment patches associated with the reference density value is arranged, and the position of the image area where the density unevenness in the plane is equal to or less than the reference value is determined. Position determining means for
An image forming apparatus comprising: control means for causing the image forming means to form image information in which the set of the plurality of image elements is arranged at the position determined by the position determining means. Calculating a fluctuation amount of the output density of the image forming apparatus with respect to a reference value;
Determining a position of an image region based on the calculated variation amount, wherein a set of a plurality of image elements that are adjustment patches associated with a reference density value is arranged , and the density unevenness in the plane is equal to or less than the reference value ; ,
Generating image information in which the set of the plurality of image elements is arranged at the determined position;
Providing the generated image information to the image forming apparatus.

Images