Image forming apparatus, information processing apparatus and program

Abstract

To accurately correct a reading unit.SOLUTION: An image forming apparatus according to an embodiment of the present invention has: an image forming unit that forms a first image on a first recording medium; a supply unit that can supply the first recording medium to the image forming unit; a reading unit that reads the first image formed on the first recording medium; a processing execution unit that executes predetermined processing based on a read image obtained by the reading unit reading the first image; and a correction unit that corrects the reading unit based on a predetermined read reference image, and a read image obtained by the reading unit reading a second image formed on a second recording medium supplied by the supply unit.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus, an information processing apparatus, and a program. [Background technology]

[0002] Conventionally, in an image forming apparatus, a technique is known in which, based on an image printed by an image forming unit read by a reading unit such as an in-line sensor, a process such as inspection of a printed image or correction of the image forming unit is performed. In this case, the image forming unit forms a printed image on a recording medium supplied from a supply unit such as a paper feed tray, and the reading unit reads the printed image in-line immediately after the image formation.

[0003] On the other hand, a configuration has been disclosed in which the reading characteristics of the reading sections in a first and second image forming device are determined based on an image printed by a first image forming device and read by a second image forming device (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of Patent Document 1, the reading unit reads the printed image using a document tray or an ADF (Auto Document Feeder), and the reading unit, which is provided on the transport path after image formation for inspecting the printed image or correcting the image forming unit, cannot be corrected.

[0005] An object of the present invention is to accurately correct the reading unit. [Means for solving the problem]

[0006] An image forming apparatus according to one aspect of the present invention comprises: An image forming apparatus for forming an image on a recording medium, comprising: Recording medium Painting an image forming section for forming an image; Notes Supply of recording media do Supply section and front Notes Before being recorded on the recording media Record A reading unit for reading an image, and the reading unit is RecordImage captured by scanning data a processing execution unit that executes a predetermined process based on the The above On the recording medium In advance Formed Gradation correction pattern The read image read by the reading unit data and, Color measurement data of the gradation correction pattern obtained in advance by an external color measurement device Based on Based on the generated reading correction parameters of the reading unit, a correction unit that corrects the reading unit; a display means for displaying a reading correction parameter of the reading unit; Have the correction unit generates read correction parameters for the other reading unit based on read data obtained by reading the gradation correction pattern by another reading unit provided in an image forming apparatus different from the image forming apparatus and the color measurement data, and the display unit displays a list of the read correction parameters for the reading unit and the read correction parameters for the other reading unit. . Effect of the Invention

[0007] According to the present invention, the reading unit can be accurately corrected. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating an example of the configuration of an image forming system according to an embodiment. [Diagram 2] FIG. 2 is a block diagram of an example of a hardware configuration of an information processing device according to an embodiment. [Diagram 3] 1 is a block diagram of an example of a hardware configuration of an image forming apparatus according to an embodiment; [Figure 4] 1 is a diagram illustrating an example of the configuration of an image forming apparatus according to a first embodiment. [Diagram 5] 2 is a block diagram of an example of a functional configuration of an image forming apparatus according to an embodiment; [Figure 6] FIG. 13 is a diagram illustrating an example of chart paper. [Figure 7] 11A and 11B are diagrams illustrating an example of separation of the intermediate transfer belt. [Figure 8] FIG. 4 is a flowchart of an example of a correction operation performed by the image forming apparatus according to the first embodiment. [Figure 9] FIG. 11 is a diagram illustrating an example of the configuration of an image forming apparatus according to a second embodiment. [Figure 10] FIG. 13 is a diagram illustrating an example of the configuration of an image forming system according to a third embodiment. [Figure 11] FIG. 11 is a flowchart showing an example of a correction operation performed by the image forming system according to the third embodiment. [Figure 12] 11A and 11B are diagrams illustrating an example of reading reference data in an image forming apparatus. [Figure 13] 13A and 13B are diagrams illustrating an example of reading reference data in another image forming apparatus. [Figure 14] FIG. 13 is a diagram showing an example of a correction operation screen for an in-line sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same components are given the same reference numerals, and duplicated explanations will be omitted as appropriate.

[0010] Furthermore, the embodiments shown below are examples of image forming apparatuses for embodying the technical ideas of the present invention, and the present invention is not limited to the embodiments shown below. Unless otherwise specified, the shapes of the components described below, their relative positions, parameter values, etc. are intended to be illustrative and not to limit the scope of the present invention. Furthermore, the sizes and positional relationships of the components shown in the drawings may be exaggerated to clarify the explanation.

[0011] The image forming apparatus according to the embodiment has an image forming unit that forms a first image on a first recording medium, a supply unit capable of supplying the first recording medium to the image forming unit, a reading unit that reads the first image formed on the first recording medium, and a processing execution unit that executes a predetermined processing based on the read image obtained by reading the first image by the reading unit.

[0012] The predetermined processing is, for example, inspection processing of the first image, color correction processing of the image forming unit when no image is formed, or color correction processing of the image forming unit when an image is formed. The color correction processing of the image forming unit when no image is formed corresponds to color calibration processing executed before image formation by the image forming apparatus. The color correction processing of the image forming unit when an image is formed corresponds to so-called real-time color correction processing executed during image formation.

[0013] In the embodiment, the reading unit corrects the second image formed on the second recording medium supplied by the supply unit based on a read image read by the reading unit and a predetermined read reference image. The second image is a correction chart image or the like for correcting the reading characteristics of the reading unit, and is an image formed in advance on the second recording medium by the image forming apparatus according to the embodiment or another image forming apparatus different from the image forming apparatus.

[0014] As when a specified process is executed, the reading unit is corrected using a second image formed on a second recording medium supplied by the supply unit, thereby accurately correcting the reading unit in the same state as when the process is executed by the process execution unit.

[0015] In the following, an embodiment will be described using an image forming system having an image forming apparatus as an example. This image forming system is, for example, an image forming system for commercial printing (production printing) that prints desired images on a large amount of recording media. Note that the terms printing, image formation, and printing in the embodiments are all synonymous.

[0016] <Example of Overall Configuration of Image Forming System 100> First, an example of the configuration of an image forming system 100 will be described with reference to Fig. 1. Fig. 1 is a diagram for explaining an example of the configuration of the image forming system 100. As shown in Fig. 1, the image forming system 100 has a client PC (Personal Computer) 101, a DFE (Digital Front End) 102, an image forming apparatus 103, and a management server 104. These are connected to each other so as to be able to communicate with each other via the Internet or the like.

[0017] The client PC 101 creates a print job that the user wants to print, and transmits the print job to the DFE 102 or the management server 104. The client PC 101 is equipped with a display unit that is a liquid crystal display, and input devices such as a mouse and a keyboard.

[0018] The DFE102 receives a print job from the client PC101 or the management server 104, creates rendering data by a RIP (Raster Image Processor) engine based on the received print job, and transmits the rendering data to the image forming apparatus 103. Here, the DFE102 is an example of an information processing apparatus.

[0019] The image forming apparatus 103 forms an image on a recording medium based on the rendering data received from the DFE102.

[0020] The management server 104 manages the print jobs received from the client PC101. Further, in response to a request from the DFE102, the management server 104 transmits the print jobs to the DFE102.

[0021] Note that a plurality of image forming apparatuses and a plurality of client PCs may be communicably connected to the image forming system 100.

[0022] <Example of the hardware configuration of the DFE102> Next, with reference to FIG. 2, the hardware configuration of the DFE102 will be described. FIG. 2 is a block diagram for explaining an example of the hardware configuration of the DFE102.

[0023] As shown in FIG. 2, the DFE102 includes a CPU (Central Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, an HDD (Hard Disk) / SSD (Solid State Drive) 204, and an I / F (Interface) 205.

[0024] Among these, the CPU 201 uses the RAM 203 as a work area and controls the overall operation of the DFE102 by executing the programs stored in the ROM 202.

[0025] The HDD / SSD 204 is used as a storage unit and stores preset setting values. The information stored in the HDD / SSD 204 may be read by the CPU 201 and used when executing a program.

[0026] The I / F 205 is an interface that enables communication between the DFE 102 and the client PC 101, the image forming apparatus 103, and the management server 104.

[0027] <Example of Hardware Configuration of Image Forming Apparatus 103> Next, the hardware configuration of the image forming apparatus 103 will be described with reference to Fig. 3. Fig. 3 is a block diagram illustrating an example of the hardware configuration of the image forming apparatus 103.

[0028] As shown in FIG. 3, the image forming apparatus 103 includes a CPU 301, a ROM 302, a RAM 303, an HDD / SSD 304, an I / F 305, an image forming unit 306, a reading unit 307, and a paper feeding unit 500.

[0029] Of these, the CPU 301 uses a RAM 303 as a working area and executes a program stored in a ROM 302 to control the overall operation of the image forming apparatus 103 .

[0030] The HDD / SSD 304 is used as a storage unit and stores preset setting values. The information stored in the HDD / SSD 304 may be read by the CPU 301 and used when executing a program.

[0031] The I / F 305 is an interface that enables communication between the image forming apparatus 103, the DEF 102, the client PC 101, and the management server 104.

[0032] The image forming unit 306 is a print engine that forms a print image on a print sheet. Here, the print sheet is an example of a first recording medium, and the print image is an example of a first image. The reading unit 307 is a reading device that reads the print image formed on the print sheet. The paper feeding unit 500 is an example of a feeding unit that can feed the print sheet to the image forming unit 306.

[0033] <Example of configuration of image forming apparatus 103> Next, the configuration of the image forming apparatus 103 will be described with reference to Fig. 4. Fig. 4 is a diagram for explaining an example of the configuration of the image forming apparatus 103. As shown in Fig. 4, the image forming apparatus 103 has tandem electrophotographic photoconductor drums 403K, 403C, 403M, and 403Y, an intermediate transfer belt 402, a secondary transfer roller 404, a paper feed section 500, a pair of conveying rollers 401, a fixing roller 405, in-line sensors 406a and 406b, a reversing path 407, and a conveying path 408.

[0034] 3 includes photoconductor drums 403K, 403C, 403M, and 403Y, an intermediate transfer belt 402, a secondary transfer roller 404, and a fixing roller 405. Also, the reading unit 307 in FIG. 3 includes in-line sensors 406a and 406b.

[0035] The image forming apparatus 103 is a so-called tandem type image forming apparatus having a configuration in which photoconductor drums 403Y, 403M, 403C, and 403K (hereinafter collectively referred to as photoconductor drums 403) of each color are arranged along an intermediate transfer belt 402, which is an endless moving means. The photoconductor drums 403Y, 403M, 403C, and 403K are arranged in order from the upstream side in the transport direction of the intermediate transfer belt 402 along the intermediate transfer belt 402, on which an intermediate transfer image to be transferred to a print paper (an example of a first recording medium) fed from a paper feeder 500 and transported by a pair of transport rollers 401 is formed.

[0036] The image forming apparatus 103 forms a full-color image by superimposing and transferring images of each color developed with toner on the surface of the photoconductor drum 403 of each color onto the intermediate transfer belt 402. Here, the intermediate transfer belt 402 is an example of an image carrier that carries an image.

[0037] The image forming device 103 transfers the full-color image formed on the intermediate transfer belt 402 onto the surface of the printing paper transported along the transport path 408, indicated by the dashed line in the figure, by the function of the secondary transfer roller 404 at the position closest to the printing paper transport path 408.

[0038] Image forming device 103 further transports the print paper on which the image has been formed, and fixes (forms) the image on the print paper by fixing roller 405. Fixing roller 405 is an example of a fixing unit that thermally fixes the print image on the print paper. Fixing roller 405 fixes the full-color toner image to the print paper by applying heat and pressure to the print paper onto which the full-color toner image has been transferred. Fixing roller 405 can generate heat by a built-in heater such as a halogen heater to heat the print paper.

[0039] When performing double-sided printing, the image forming device 103 forms an image on the front side, then transports the print paper to a reversal path 407 in a transport path 408, inverts the paper, and transports it again to the position of the secondary transfer roller 404.

[0040] The paper feed section 500 has a paper feed tray 501, a pickup roller 502, and a paper feed roller 503. The paper feed tray 501 is an example of a storage section capable of storing print paper.

[0041] The paper feed tray 501 accommodates a plurality of overlapping printing papers. The first recording medium includes printing papers such as recording paper (transfer paper), but is not limited thereto, and may be coated paper, cardboard, an overhead projector (OHP) sheet, a plastic film, a prepreg, copper foil, or the like, as long as it is a medium on which an image can be formed (recorded).

[0042] The paper feed unit 500 picks up the printing papers stacked and stored in the paper feed tray 501 in order from the top by a pickup roller 502, and supplies the picked up printing papers to the conveying roller pair 401 by using a pair of rollers, paper feed rollers 503. The paper feed unit 500 may be configured to have other rollers for conveying.

[0043] The image forming apparatus 103 includes in-line sensors 406a and 406b (hereinafter collectively referred to as in-line sensor 406) downstream of a fixing roller 405 in the conveying direction of a print sheet.

[0044] In-line sensor 406 reads both sides of the print paper by fixing roller 405, and obtains read image data of the image fixed on the print paper. Note that two in-line sensors 406 (406a, 406b) are not necessarily required, and only in-line sensor 406a may be used. When only sensor 406a is used, reading is performed by in-line sensor 406a at the time when an image is formed on the front side. Image forming apparatus 103 then forms an image on the back side.

[0045] Here, the in-line sensor 406 is a CCD (Charge Coupled Device) line sensor in which pixels that output electrical signals according to the intensity of the received light are arranged in a one-dimensional array. The direction in which the pixels are arranged intersects with the conveyance direction of the print paper. The in-line sensor 406 also includes a pixel array that receives red light (R), a pixel array that receives green light (G), and a pixel array that receives blue light (B).

[0046] The in-line sensor 406 outputs an electrical signal according to the light intensity of the reflected light from the print image formed on the print paper by the pixel array of each color. The image forming apparatus 103 uses the light intensity (density) of each color of the image read by the in-line sensor 406 as color information for correcting the print color.

[0047] The in-line sensor 406 may include a light source that irradiates light onto the printing paper. By irradiating the printing paper with light from the light source, it is possible to ensure the brightness for reading by the in-line sensor 406. Also, the in-line sensor 406 may include a CMOS (Complementary metal-oxide-semiconductor) or a PD (Photo Diode) array, etc., instead of a CCD.

[0048] <Example of Functional Configuration of Image Forming Apparatus 103> Next, the functional configuration of the image forming apparatus 103 will be described with reference to FIG. 5 and also with reference to the configuration diagram of FIG. 4 as appropriate. FIG. 5 is a block diagram for explaining an example of the functional configuration of the image forming apparatus 103. As shown in FIG. 5, the image forming apparatus 103 has an image formation control unit 11, a stop control unit 12, a paper feed control unit 13, a storage unit 14, an inspection processing unit 15, a non-printing color correction processing unit 16, a printing color correction processing unit 17, and a reading characteristic correction unit 18. Of these, the function of the storage unit 14 is realized by the HDD / SSD 304 or the like. In addition, each function of the components other than the storage unit 14 is realized by the CPU 301 in FIG. 3 executing a predetermined program, or the like. Note that, although only the main components are shown in FIG. 5, the image forming apparatus 103 may also have components other than those described above.

[0049] The image forming control unit 11 has a function of controlling the image forming operation by the image forming unit 306 .

[0050] The stop control unit 12 has a function of stopping the operation of the image forming unit 306 when the reading characteristic correction unit 18 corrects the reading characteristic of the reading unit 307.

[0051] The stop control unit 12 also has a heat generation stop control unit 121 and a separation control unit 122. The heat generation stop control unit 121 stops the heat generation of the fixing roller 405 in the image forming unit 306. The separation control unit 122 can separate the intermediate transfer belt 402 from the transport path 408 along which the print paper is transported.

[0052] The paper feed control unit 13 has a function of controlling the operation of the paper feed unit 500 .

[0053] The storage unit 14 stores inspection standard image data 141 used by the inspection processing unit 15, color correction standard data 142 used by the non-printing color correction processing unit 16 and the printing color correction processing unit 17, and reading standard image data 143 used by the reading characteristic correction unit 18, etc.

[0054] The inspection processing unit 15 performs inspection processing of the print image formed on the print paper. For example, the inspection processing unit 15 compares the read image obtained by reading the print image by the reading unit 307 with a predetermined inspection reference image acquired by referring to the storage unit 14. If a position shift exceeding a predetermined position shift threshold or a color shift exceeding a predetermined color shift threshold is detected with respect to the inspection reference image, the print paper corresponding to the read image is excluded as a defective product. In addition, if the print paper or the print image has scratches or stains, the print paper corresponding to the read image can also be excluded as a defective product.

[0055] The non-printing color correction processing unit 16 executes color correction processing of the image forming unit 306 during non-image formation. Note that the non-image formation time refers to the time when the image forming apparatus 103 is not forming an image.

[0056] For example, before the image forming device 103 forms images continuously on a large amount of printing paper, the non-printing color correction processing unit 16 compares the read image obtained by reading the print image with the reading unit 307 with a predetermined color correction reference image acquired by referring to the storage unit 14. Then, the non-printing color correction processing unit 16 adjusts color conversion parameters such as a gamma curve in the image forming unit 306 to perform color correction in the image forming unit 306 so that the color of the read image matches the color of the color correction reference image.

[0057] The timing for executing the color correction process by the non-printing color correction processor 16 is not limited to before image formation by the image forming apparatus 103, but may be periodically at predetermined intervals.

[0058] The printing color correction processing unit 17 executes color correction processing of the image forming unit 306 during image formation. During image formation means a time when the image forming apparatus 103 is forming an image. The processing by the printing color correction processing unit 17 corresponds to so-called real-time color correction.

[0059] For example, when the image forming device 103 is continuously forming images on a large amount of printing paper, the printing time color correction processing unit 17 uses the reading unit 307 to read the printed image on the printing paper immediately after the image formation. Then, the reading unit 307 compares the image read by the reading unit 307 with a predetermined color correction reference image acquired by referring to the storage unit 14, and adjusts color conversion parameters such as a gamma curve in the image forming unit 306 so that the color of the read image matches the color of the color correction reference image, thereby correcting the print color by the image forming unit 306. The image forming device 103 reflects the correction result in the image formation on the printing paper after the correction process is executed.

[0060] Each of the above-mentioned inspection processing unit 15, non-printing color correction processing unit 16, and printing color correction processing unit 17 is an example of a processing execution unit that executes a specified process based on the read image read by the reading unit 307 of the printed image formed on the printing paper.

[0061] The reading characteristic correction unit 18 is an example of a correction unit that corrects the reading unit 307 based on a read image obtained by reading the reading unit 307 from a correction chart image formed on chart paper supplied by the paper feed unit 500, and a predetermined reading reference image.

[0062] Here, the chart paper is an example of a second recording medium, and the correction chart image is an example of a second image. The chart paper includes a correction chart image that has been formed in advance by the image forming apparatus 103 or another image forming apparatus different from the image forming apparatus 103.

[0063] When the reading characteristic correction unit 18 performs correction, the image forming apparatus 103 stores chart paper in a paper feed tray 501 of a paper feed unit 500 , and supplies the chart paper to the image forming unit 306 by the paper feed unit 500 under the control of the paper feed control unit 13 .

[0064] In other words, the image forming apparatus 103 transports the chart paper along the transport path 408 in the same manner as when printing paper is transported during image formation, and the reading unit 307 reads the correction chart image on the chart paper that has passed the position of the fixing roller 405. Note that the chart paper is placed in the paper feed tray 501 manually, for example, by a user or an administrator of the image forming apparatus 103.

[0065] During correction by the reading characteristic correction unit 18, a print image is not formed on the chart paper, so the operation of the image forming unit 306 is stopped by the stop control unit 12. Furthermore, if the fixing roller 405 generates heat, power consumption is wasted, and the chart paper may become heated when passing the position of the fixing roller 405, damaging the correction chart image on the paper. Therefore, the image forming device 103 stops the heat generation of the fixing roller 405 by the heat generation stop control unit 121.

[0066] Furthermore, residual toner that was not transferred to the print paper during image formation may adhere to the intermediate transfer belt 402, and if the chart paper comes into contact with the residual toner, the residual toner may contaminate the correction chart image. Therefore, during correction by the reading characteristic correction unit 18, the image forming apparatus 103 separates the intermediate transfer belt 402 from the transport path 408 by the separation control unit 122 so that the intermediate transfer belt 402 does not come into contact with the chart paper transported along the transport path 408.

[0067] In this state, the reading unit 307 reads the correction chart image on the chart paper transported along the transport path 408. The reading characteristic correction unit 18 compares the image read by the reading unit 307 with the read reference image acquired by referring to the storage unit 14, and corrects the reading characteristics of the reading unit 307 so that the color of the read image matches the color of the read reference image. For example, the reading characteristics of the reading unit 307 can be corrected by adjusting the gain and offset of each color in the CCD of the reading unit 307.

[0068] <Chart paper example> Next, the chart paper used for correction by the reading characteristic correction unit 18 will be described with reference to Fig. 6. Fig. 6 is a diagram for explaining an example of chart paper.

[0069] The image forming apparatus 103′ in FIG. 6 is another image forming apparatus different from the image forming apparatus 103 according to the embodiment, and is an image forming apparatus that serves as a reference for correcting the reading characteristics of the reading unit 307 in the image forming apparatus 103.

[0070] The chart paper 181 is a paper on which a correction chart image 181a is formed by the image forming device 103'. The correction chart image 181a is an image in which color patches for each of a plurality of colors are formed in an array. Note that a color patch means an area on the chart paper where one color is formed. The number and arrangement of the color patches, as well as the type of color, can be appropriately selected according to the application.

[0071] The image forming apparatus 103' forms a correction chart image 181a on a chart paper 181, reads the correction chart image 181a using a reading unit included in the image forming apparatus 103', and stores this read image in a storage device or the like as read reference image data.

[0072] The chart paper 181 on which the correction chart image 181a is formed is carried by a user or administrator of the image forming apparatus 103, and is set in the paper feed tray 501 of the paper feed unit 500 in the image forming apparatus 103 when the reading unit 307 is corrected. The read reference image data is transferred to the image forming apparatus 103 via a network or a storage medium, and stored in the storage unit 14 (see FIG. 5) of the image forming apparatus 103. After that, the reading unit 307 in the image forming apparatus 103 is corrected.

[0073] In this embodiment, an example in which the correction chart image 181a is formed by the image forming apparatus 103' is shown, but the present invention is not limited to this. The image forming apparatus 103 itself may use a chart paper on which a correction chart image has been formed in the past as the second recording medium, and the read image of the chart paper may be used as the read reference image data.

[0074] Also, a correction chart image and reading reference image data can be prepared according to the type of image formed by the image forming device 103, such as a photo image or a text image. In this case, the type of image is associated in advance with the correction chart image and reading reference image data, and the image forming device 103 uses the correction chart image and reading reference image data according to the type of image in correcting the reading unit 307.

[0075] Furthermore, when there are a large number of color patches, the correction chart image can be formed by dividing the color patches into multiple chart papers. When the image forming apparatus 103 uses multiple chart papers to correct the reading unit, the multiple chart papers are set in the paper feed tray 501 and fed sequentially by the paper feed unit 500.

[0076] <Example of separation of intermediate transfer belt 402> Next, separation of the intermediate transfer belt 402 will be described with reference to Fig. 7. Fig. 7 shows an example of the intermediate transfer belt 402 separated from the transport path 408 under the control of the separation control unit 122 (see Fig. 5).

[0077] 7, the position of the secondary transfer roller 404 has moved in a direction away from the transport path 408. The movement of the secondary transfer roller 404 can be performed by a contact / separation mechanism using an eccentric cam or the like. As a result of the movement of the secondary transfer roller 404, the intermediate transfer belt 402 supported by the secondary transfer roller 404 is separated from the transport path 408 by a distance D. This prevents the chart paper transported along the transport path 408 from coming into contact with the intermediate transfer belt 402, and prevents the correction chart image from being contaminated by residual toner remaining on the intermediate transfer belt 402.

[0078] Although FIG. 7 shows an example of a configuration in which only the secondary transfer roller 404 moves, the photosensitive drum 403, the secondary transfer roller 404, and the intermediate transfer belt 402 may all move.

[0079] <Example of Correction Operation of the Reading Unit 307 by the Image Forming Apparatus 103> Next, a correction operation of the reading unit 307 by the image forming apparatus 103 will be described with reference to Fig. 8 and also with reference to the functional configuration diagram of Fig. 5 as appropriate. Fig. 8 is a flowchart for explaining an example of the correction operation of the reading unit 307 by the image forming apparatus 103.

[0080] In addition, the image forming apparatus 103 is set to correct the reading unit 307 at a predetermined timing in the activated state, and Fig. 8 shows the operation starting from the timing when the image forming apparatus 103 starts correcting the reading unit 307. The above-mentioned predetermined timing can be appropriately selected from a timing every time image formation is performed by the image forming apparatus 103, a timing every time a predetermined period is performed, etc.

[0081] First, in step S81, the reading characteristic correction unit 18 refers to the storage unit 14 to obtain the read reference image data.

[0082] Next, in step S82, heat generation stop control unit 121 stops heat generation from fixing roller 405 (see FIG. 4).

[0083] Next, in step S83, the separation control unit 122 separates the intermediate transfer belt 402 from the transport path 408 along which the print paper is transported.

[0084] Next, in step S84, the paper feed section 500, under the control of the paper feed control section 13, feeds the chart paper accommodated in the paper feed tray 501.

[0085] Next, in step S85, the reading unit 307 reads the correction chart image formed on the chart paper being transported along the transport path 408 (see FIG. 4).

[0086] Next, in step S86, the image read by the reading unit 307 is compared with a reference image obtained by referring to the storage unit 14, and the reading characteristics of the reading unit 307 are corrected so that the color of the read image matches the color of the reference image.

[0087] In this manner, the image forming apparatus 103 can correct the reading characteristics of the reading unit 307.

[0088] <Functions and Effects of Image Forming Apparatus 103> Next, the effects of the image forming apparatus 103 will be described. Conventionally, in image forming apparatuses, a technique is known in which a print image printed by an image forming unit is inspected and a color correction of the image forming unit is performed based on an image read by a reading unit from the print image printed by the image forming unit. In the inspection of a print image and the correction of the image forming unit, the image forming unit forms a print image on a recording medium supplied from a supply unit such as a paper feed tray, and the reading unit reads the print image inline immediately after the image is formed.

[0089] In this case, if the reading characteristics of the reading unit change over time or differ from one image forming apparatus to another, the accuracy of the inspection process and color correction process described above may decrease.

[0090] On the other hand, in order to correct changes over time in the reading characteristics of the reading unit, a configuration is disclosed in which the reading characteristics of the reading units in the first and second image forming devices are determined based on an image printed by the first image forming device and read by the second image forming device.

[0091] However, in the disclosed configuration, the reading unit reads the printed image using a platen or ADF, and it is not possible to correct the reading unit for inspecting the printed image or correcting the image forming unit.

[0092] In this embodiment, the image forming device 103 corrects the reading unit based on a read image obtained by the reading unit reading a correction chart image (second image) formed on chart paper (second recording medium) supplied by a paper feed unit (supply unit) and a predetermined reading reference image.

[0093] The image forming apparatus 103 uses a correction chart image formed on chart paper transported from a paper feed unit along a transport path for image formation, similar to printing paper (first recording medium) in inspection, color correction, etc., so that the usage state of the reading unit can be the same as when inspection, color correction, etc. are performed. This makes it possible to accurately correct the reading unit.

[0094] In this embodiment, the image forming apparatus 103 prepares in advance a chart paper on which a correction chart image is formed, and uses this to correct the reading unit. Therefore, the image forming apparatus 103 does not need to form a correction chart image on chart paper every time the reading unit is corrected, and the image forming apparatus 103 can reduce the effort, time, and cost required for correcting the reading unit.

[0095] In this embodiment, the image forming apparatus 103 stops the operation of the image forming unit by the stop control unit when the reading unit reads the chart paper, which enables the image forming apparatus 103 to transport the chart paper from the paper feed unit along the transport path for image formation.

[0096] Furthermore, in this embodiment, the image forming apparatus 103 stops the heat generation of the fixing roller (fixing unit) when the reading unit reads the chart paper. This allows the image forming apparatus 103 to save power consumption for heating the fixing roller, and also prevents the chart paper from being heated and damaging the correction chart image when the chart paper passes the fixing roller.

[0097] In this embodiment, when the reading unit reads the chart paper, the image forming apparatus 103 separates the intermediate transfer belt (image carrier) from the transport path along which the print paper is transported. This allows the image forming apparatus 103 to prevent contamination of the correction chart image caused by the chart paper coming into contact with residual toner adhering to the intermediate transfer belt.

[0098] [Second embodiment] Next, an image forming system 100a according to a second embodiment will be described. The same components as those in the first embodiment will be denoted by the same reference numerals, and duplicated descriptions will be omitted as appropriate. This also applies to the other embodiments described below.

[0099] Fig. 9 is a diagram showing an example of the configuration of an image forming apparatus 103a included in an image forming system 100a. As shown in Fig. 9, the image forming apparatus 103a has a photoconductor drum 403W in addition to photoconductor drums 403K, 403C, 403M, and 403Y.

[0100] Photoconductor drum 403K can form an image using black (K) toner, photoconductor drum 403C can form an image using cyan (C) toner, photoconductor drum 403M can form an image using magenta (M) toner, photoconductor drum 403Y can form an image using yellow (Y) toner, and photoconductor drum 403W can form an image using white (W) toner.

[0101] K, C, M, and Y are process colors, and are an example of a first color. A process color is a color expressed in a printed matter by combining four basic colors of toner. On the other hand, white is a color other than the process colors, that is, a so-called spot color, and is an example of a second color. In addition to white, the image forming device 103a can form an image using a number of other spot color toners, such as fluorescent pink and fluorescent yellow.

[0102] When correcting the reading characteristics of the reading unit for such spot colors, if the image forming apparatus 103a itself were to form a correction chart image, it would be necessary to replace the photosensitive drum a number of times corresponding to the number of spot colors, which could be time-consuming and laborious.

[0103] In the embodiment, the image forming system 100a prepares in advance a chart paper on which a correction chart image is formed as described above, and uses this to correct the reading unit. Therefore, if a chart paper on which a correction chart image including multiple spot colors is formed is prepared in advance, it becomes unnecessary to replace the photoconductor drum a number of times corresponding to the number of spot colors. This allows the image forming system 100a to reduce the effort and time required to correct the reading unit.

[0104] Effects other than those described above are similar to those described in the first embodiment.

[0105] [Third embodiment] An image forming system 100b according to the third embodiment will be described.

[0106] <Configuration of image forming system 100b> 10 is a diagram showing an example of the configuration of an image forming system 100b. The image forming system 100b includes an image forming apparatus 103, two image forming apparatuses 103' corresponding to other image forming apparatuses, and a management server 104. The image forming apparatuses 103, 103', and the management server 104 are communicatively connected to each other via a network N. The image forming system 100b is also communicatively connected to an external color measuring device 105 via the network N. The external color measuring device 105 is, for example, a spectrophotometer.

[0107] <Correction Operation by Image Forming System 100b> Fig. 11 shows an example of an in-line sensor correction operation by image forming system 100b. Fig. 11 shows the operation of image forming system 100b triggered by the timing when image forming apparatus 103 and another image forming apparatus 103' start generating correction parameters for the in-line sensors included in each of them. Image forming apparatus 103 and another image forming apparatus 103' each start generating correction parameters in response to an operation input by a user, for example.

[0108] First, in step S10, the image forming system 100b causes the image forming apparatus 103 to adjust the state of the image forming unit 306 included in the image forming apparatus 103.

[0109] Next, in step S20, the image forming system 100b causes the image forming apparatus 103 to form an image of a gradation correction pattern used for correcting the in-line sensor 406 of the image forming apparatus 103 on chart paper.

[0110] Next, in step S30, the image forming system 100b causes the in-line sensor 406 of the image forming apparatus 103 to read the gradation correction pattern formed on the chart paper.

[0111] Next, in step S40, the image forming system 100b stores the read data of the gradation correction pattern read by the in-line sensor 406 of the image forming apparatus 103 in the RAM 203 or the like.

[0112] Next, in step S50, the image forming system 100b uses the external colorimetric device 105 to measure the gradation correction pattern formed by the image forming device 103, and stores the colorimetric data. The colorimetric data is a target (standard) for the image forming device 103 itself. Of the image forming devices 103 and 103' included in the image forming system 100b, the standard image forming device uses the colorimetric data when generating read standard data indicating the correspondence between the colorimetric data and the read data by the inline sensor. The image forming devices 103 and 103' can input the colorimetric data from the external colorimetric device 105, for example, via the network N or by using a portable recording medium such as a USB (Universal Serial Bus) memory or an SD card.

[0113] Next, in step S60, the image forming system 100b causes the image forming device 103 to associate the read data with the color measurement data for each color patch included in the tone correction pattern, and generates read reference data.

[0114] The read reference data is a pair of read data and color measurement data. The image forming system 100b stores the read reference data in the HDD / SSD 304 in the image forming apparatus 103. Alternatively, in step S70, the image forming system 100b transmits the read reference data to the image forming apparatus 103' via the network N and stores the read reference data in the HDD / SSD 304 in the image forming apparatus 103'. The image forming system 100b may also store the read reference data in a storage server device or the like independent of the image forming apparatuses 103 and 103'.

[0115] Of the read reference data, the image forming apparatus 103' does not use the read data by the inline sensor 406 of the image forming apparatus 103. The image forming apparatus 103' uses the read reference data in order to keep a reference data set and for comparison when verifying the accuracy of the correction parameters.

[0116] Next, in step S80, the image forming system 100b generates and registers correction parameters for correcting the inline sensor 406 of the image forming device 103 to match either the reading reference data generated in step S60 or previously generated reading reference data.

[0117] Next, in step S90, the image forming system 100b holds the chart paper on which the gradation correction pattern has been formed in step S20, in the image forming device 103. Note that holding the chart paper in this case means storing the chart paper.

[0118] Next, in step S100, the chart paper held in step S90 is set (stored) in the paper feed tray 501 of the image forming apparatus 103'. By setting the chart paper on which an image has already been formed in the paper feed tray 501 of the image forming apparatus 103' that is the target of correction, it becomes unnecessary to form an image of a gradation correction pattern on the chart paper by the image forming apparatus 103'. Since it takes time to install or replace the photoconductor drum 403W for the spot color, mainly for white toner, by eliminating the need to form an image of a gradation correction pattern on the chart paper, a significant reduction in the number of steps can be achieved.

[0119] Next, in step S110, the image forming system 100b causes the image forming apparatus 103′ to separate the photosensitive drum 403 of the image forming apparatus 103′ from the intermediate transfer belt 402, and then conveys chart paper from the paper feed tray 501 of the image forming apparatus 103′.

[0120] Next, in step S120, the image forming system 100b reads the gradation correction pattern on the conveyed chart paper by the in-line sensor 406 of the image forming apparatus 103'.

[0121] Next, in step S130, the image forming system 100b associates the read data read by the inline sensor 406 of the image forming apparatus 103' with the read reference data stored in step S70. In this association, the image forming apparatus 103' associates the read data by the inline sensor 406 of the image forming apparatus 103 with the colorimetric data by the external colorimetric device 105, and further associates the read data by the inline sensor 406 of the image forming apparatus 103'.

[0122] Next, in step S140, the image forming system 100b generates and registers correction parameters for the in-line sensor 406 of the image forming apparatus 103' so as to match the read reference data, using the image forming apparatus 103'.

[0123] In this manner, the image forming system 100b can generate correction parameters for the in-line sensor 406 of the image forming apparatus 103 and correction parameters for the in-line sensor 406 of the image forming apparatus 103′. Also, the image forming system 100b can correct each in-line sensor 406 using these correction parameters.

[0124] <Example of reading reference data> Fig. 12 is a diagram showing an example of read reference data in which the read data and color measurement data generated in step S60 in the operation of Fig. 11 are associated with each other. That is, Fig. 12 shows the read reference data generated by the image forming apparatus 103.

[0125] Fig. 13 is a diagram showing an example of read reference data in which the read data and color measurement data generated in step S130 in the operation of Fig. 11 are associated with each other. That is, Fig. 13 shows the read reference data generated by the image forming apparatus 103'.

[0126] <Example of correction operation screen> 14 is a diagram showing an example of a correction operation screen 110 for an in-line sensor of the image forming apparatuses 103 and 103' included in the image forming system 100b. This correction operation screen 110 is a screen displayed on at least one of the operation panels of the image forming apparatuses 103 and 103', and is a screen on which a user or the like can input operations.

[0127] As shown in FIG. 14, the correction operation screen 110 has a read reference data generation button 111, a read reference data registration button 112, an inline sensor correction execution button 113, a correction parameter list button 114, a chart print & read button 115, a chart color measurement button 116, and a chart transport & read button 117.

[0128] The read reference data generation button 111 is a button for executing the operations of steps S10 to S60 in the correction operation shown in Fig. 11. When this button is pressed, the image forming device 103 forms an image of a gradation correction pattern on chart paper, reads the formed gradation correction pattern with the in-line sensor 406, measures the color of the gradation correction pattern with the external colorimetric device 105, and then generates read reference data.

[0129] The reading reference data registration button 112 is a button for importing and registering the reading data obtained by the inline sensor 406 during image design in the image forming device 103, the colorimetric data measured by the external colorimetric device 105, and the reading reference data into the image forming device 103.

[0130] The inline sensor correction execution button 113 is a button for executing the operations of steps S10 to S90 in the correction operation shown in Fig. 11. When this button is pressed, the image forming apparatus 103 forms an image of a gradation correction pattern on chart paper, reads the formed gradation correction pattern with the inline sensor 406, and measures the gradation correction pattern with the external colorimetric device 105. The read data by the inline sensor 406 and the colorimetric data by the external colorimetric device 105 are read in different orders, and the color patches are not arranged in order of gradation. Therefore, the read data and the colorimetric data are associated with each other for each color patch ID and rearranged in order of ID. After that, the image forming apparatus 103 generates correction parameters based on the acquired information so as to match the registered read reference data, and registers them.

[0131] The correction parameter list button 114 is a button for displaying a list of correction parameters held for each of the image forming apparatuses 103 and 103' included in the image forming system 100b. The correction parameter list button 114 is used for correction parameter analysis performed when the result of color accuracy evaluation after the correction parameters are generated is NG, for cause analysis performed when a failure occurs in the market, and for reinstalling the correction parameters in the image forming apparatus as provisional information when a part is suddenly replaced in the image forming apparatus 103 or 103'.

[0132] When there are multiple image forming devices that perform correction using the read reference data, the image forming system 100b generates different correction parameters for each of the multiple image forming devices. The correction parameter list for each image forming device 103 and 103' that can be viewed by pressing the correction parameter list button 114 corresponds to the list of image forming devices shown in Fig. 13. When there are multiple image forming devices, data is added to Fig. 13 accordingly.

[0133] The chart print & read button 115 is a button for executing the operations of steps S10 to S40 in the correction operation shown in Fig. 11. When this button is pressed, the image forming apparatus 103 forms an image of a gradation correction pattern required for correction on chart paper. When generating correction parameters for a spot color such as white, it takes a lot of time to set or replace a photoconductor drum for the spot color in the image forming apparatus. In contrast, the operation of the image forming system 100b in response to pressing of the chart print & read button 115 makes it possible to generate correction parameters for the spot color without performing the above-mentioned setting or replacement work in the other image forming apparatus 103'.

[0134] The chart color measurement button 116 is a button for executing the operations of steps S10 to S30 in the correction operation shown in Fig. 11. Pressing this button enables color measurement of the gradation correction pattern by the external color measurement device 105. This is used when evaluating the density of the gradation correction pattern or updating the color measurement data by storing the chart paper.

[0135] The chart transport and reading button 117 is a button for executing the operations of steps S70 and 100 to S140 in the correction operation shown in FIG. 11 in response to pressing of the button.

[0136] Although the embodiments have been described above, the present invention is not limited to the above specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims.

[0137] Note that the image forming system 100 may be configured by providing some of the functions of the image forming apparatus 103, or some or all of the functions of the DFE 102 in an external device. An example of the external device is a cloud server. Alternatively, the DFE 102 may include some of the functions of the image forming apparatus 103.

[0138] In addition, when a post-processing device that performs inspection processing, color correction processing, etc. is provided separately from the image forming device, at a stage downstream of the image forming device, the post-processing device may be provided with some of the functions of the image forming device 103.

[0139] Further, in the above-described embodiment, an image forming system including an electrophotographic image forming apparatus has been described, but the present invention is also applicable to an image forming system including an image forming apparatus of another type, such as an inkjet type.

[0140] In addition, all numbers such as ordinal numbers and quantities used in the description of the embodiments are merely examples for specifically explaining the technology of the present invention, and the present invention is not limited to the exemplified numbers. Furthermore, the connection relationships between the components are merely examples for specifically explaining the technology of the present invention, and the connection relationships for realizing the functions of the present invention are not limited to these.

[0141] In addition, the division of blocks in the functional block diagram is an example, and multiple blocks may be realized as one block, one block may be divided into multiple blocks, and / or some functions may be transferred to another block. Furthermore, the functions of multiple blocks having similar functions may be processed in parallel or in a time-division manner by a single piece of hardware or software.

[0142] The embodiment also includes a program. For example, the program is a program used in an image forming apparatus having an image forming unit that forms a first image on a first recording medium, a supply unit that can supply the first recording medium to the image forming unit, a reading unit that reads the first image formed on the first recording medium, and a processing execution unit that executes a predetermined processing based on a read image obtained by reading the first image by the reading unit, and causes a computer to execute a process of correcting the reading unit based on a read image obtained by reading a second image formed on a second recording medium supplied by the supply unit and a predetermined read reference image. Such a program can provide the same effect as the image forming system described above.

[0143] Furthermore, each function of the above-described embodiments can be realized by one or more processing circuits. Here, the term "processing circuit" in this specification includes a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, and a device such as an ASIC (Application Specific Integrated Circuit), a DSP (digital signal processor), an FPGA (field programmable gate array), or a conventional circuit module designed to execute each function described above. [Explanation of symbols]

[0144] 11 Image formation control section 12 Stop control section 13 Paper feed control unit 14 Storage area 15 Inspection processing unit (an example of a processing execution unit) 16 Non-printing color correction processing unit (an example of a processing execution unit) 17 Printing color correction processing unit (an example of a processing execution unit) 18 Reading characteristic correction unit (an example of a correction unit) 100 Image forming system 101 Client PC 102 DFE (an example of information processing equipment) 103 Image forming device 104 Management Server 181 Chart paper (an example of a second recording medium) 181a Correction chart image (example of the second image) 306 Image forming section 307 Reading Unit 402 Intermediate transfer belt (an example of an image carrier) 403 Photoconductor drum 405 Fixing roller (an example of a fixing unit) 406 In-line sensor (example of reading section) 407 Reverse Path 408 Transport Route 500 Paper feed section (example of supply section) 501 Paper feed tray 502 Pickup roller 503 Paper feed roller [Prior art documents] [Patent documents]

[0145] [Patent Document 1] JP 2015-176517 A

Claims

1. An image forming apparatus for forming an image on a recording medium, comprising: an image forming unit for forming an image on the recording medium; a supply unit that supplies the recording medium to the image forming unit; a reading unit that reads the image formed on the recording medium; a processing execution unit that executes a predetermined process based on the read image data obtained by reading the image by the reading unit; a correction unit that corrects the reading unit based on read correction parameters of the reading unit generated based on read image data obtained by the reading unit reading a gradation correction pattern formed in advance on the recording medium supplied by the supply unit and color measurement data of the gradation correction pattern obtained in advance by an external color measurement device; a display means for displaying the reading correction parameters of the reading unit, the correction unit generates a reading correction parameter for the other reading unit based on read data obtained by reading the gradation correction pattern by the other reading unit provided in the other image forming apparatus different from the image forming apparatus and the color measurement data; The display means displays a list of the reading correction parameters of the reading unit and the reading correction parameters of the other reading units. Image forming device.

2. The predetermined process is at least one of an inspection process of the image, a color correction process of the image forming unit when no image is formed, or a color correction process of the image forming unit when an image is formed. The image forming apparatus according to claim 1 .

3. A storage section for storing the recording medium, The supply unit supplies the recording medium accommodated in the accommodation unit.

3. The image forming apparatus according to claim 1, wherein the image forming apparatus comprises:

4. a stop control unit that stops the operation of the image forming unit when the reading unit reads the gradation correction pattern; The image forming apparatus according to claim 1 .

5. the image forming unit has a fixing unit that thermally fixes the image on the recording medium, The stop control unit stops heat generation of the fixing unit. The image forming apparatus according to claim 4 .

6. the image forming unit has an image carrier that carries an image, The stop control unit separates the image carrier from a transport path along which the recording medium is transported.

6. The image forming apparatus according to claim 4 or 5.

7. The image forming unit forms an image in a first color and a second color different from the first color. The image forming apparatus according to claim 1 .

8. the first color is a process color; The second color is a color other than a process color. The image forming apparatus according to claim 7.

9. An information processing device that can be attached to an image forming device having an image forming unit that forms an image on a recording medium and a supply unit that supplies the recording medium to the image forming unit, a reading unit that reads the image formed on the recording medium; a processing execution unit that executes a predetermined process based on the read image data obtained by reading the image by the reading unit; and a correction unit that corrects the reading unit based on read correction parameters of the reading unit generated based on read image data obtained by the reading unit reading a gradation correction pattern formed in advance on the recording medium supplied by the supply unit and color measurement data of the gradation correction pattern obtained in advance by an external color measurement device. Information processing device.

10. An image forming unit that forms an image on a recording medium; a supply unit that supplies the recording medium to the image forming unit; a reading unit that reads the image formed on the recording medium; a processing execution unit that executes a predetermined process based on read image data obtained by reading the image by the reading unit, The reading unit is corrected based on read correction parameters of the reading unit generated based on read image data obtained by the reading unit reading a gradation correction pattern formed in advance on the recording medium supplied by the supply unit and color measurement data of the gradation correction pattern obtained in advance by an external color measurement device. A program that causes a computer to carry out processing.

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