JP2023172884A - Image formation system for inspecting quality of image formed on recording medium - Google Patents

Abstract

To reduce influence of reflection in reading of a test chart for generating a correction parameter used in inspection of the quality of an image.SOLUTION: At least one processor is configured to execute control of an image formation device so as to form a test chart on a first recording medium on the basis of image data corresponding to a test chart which is a prescribed image, and inspection of an inspection object image formed on a second recording medium on the basis of first image data obtained by reading, by a reading device, the inspection object image formed on a second recording medium by the image formation device, and the image data corresponding to the inspection object image, wherein the test chart includes a plurality of light patch images and a plurality of dark patch images formed so as to surround the plurality of light patch images, and respective concentrations of the plurality of light patch images and the plurality of dark patch images are different.SELECTED DRAWING: Figure 11

Description

The present invention relates to an image forming system having an inspection device for inspecting the quality of an image formed on a recording medium.

2. Description of the Related Art Conventionally, an inspection apparatus is known that inspects the quality of an image formed on a recording medium, that is, whether or not the image is formed on the recording medium as indicated by image data (Patent Document 1). The inspection device inspects an image formed on a recording medium by using, for example, RIP data as reference data and comparing inspection target data obtained by reading an image of a printed matter with a scanner or the like with the reference data. The inspection device inspects the tint of the image, for example, by comparing red (R) data in the reference data and red (R) data in the inspection target data. Similar processing is performed for green (G) and blue (B), respectively.

Here, the inspection target data read by the scanner is an image formed on a recording medium using yellow (Y), magenta (M), cyan (C), and black (K) toner by an image forming apparatus based on image data. This is image data obtained by reading. Therefore, even if the image is formed on the recording medium as indicated by the RIP data corresponding to the reference image, the color tone of the image indicated by the inspection target data may differ (error) from the color tone of the image indicated by the reference image. component) is generated. To solve this problem, a configuration is available in which a test chart having a predetermined pattern is formed on an image forming apparatus, and the test chart is read with a scanner to calculate correction parameters used to correct error components for RIP data. Are known.

JP2020-067732A

When reading a test chart with a scanner, the reading result of a pixel of interest may be influenced by a region different from the pixel of interest within the test chart. In the following description, a phenomenon in which the reading result of a pixel of interest is influenced by the surrounding area will be referred to as "reflection." If the reading results of the test chart are affected by reflection, the accuracy of the correction parameters may deteriorate. As a result, the accuracy with which the quality of the image formed on the recording medium is inspected decreases.

The present invention provides a technique for reducing the influence of reflection in reading a test chart for generating correction parameters used for inspecting image quality.

According to one aspect of the present invention, there is provided an image forming apparatus that forms an image on a recording medium based on image data, and an image forming apparatus that forms an image on a recording medium that is conveyed from the image forming apparatus. A reading means that reads through a transparent member at a reading position in a conveyance direction, the light emitting means emitting light to the recording medium, and a sensor receiving light emitted by the light emitting means and reflected by the recording medium. and a black background member provided at the reading position on the opposite side of the reading means with respect to the conveyance path along which the recording medium is conveyed; In the image forming system including: one processor, the at least one processor is configured to image the test chart so as to form the test chart on the first recording medium based on the image data corresponding to the test chart, which is a predetermined image. controlling a forming device; first image data obtained by the reading device reading an image to be inspected formed on a second recording medium by the image forming device; and the image corresponding to the image to be inspected. and inspecting the inspection target image formed on the second recording medium based on the data, and the test chart includes a plurality of light patch images and a plurality of light patch images. a plurality of dark patch images formed to surround a patch image, the plurality of light patch images and the plurality of dark patch images having different densities.

According to the present invention, it is possible to reduce the influence of reflection when reading a test chart for generating correction parameters used for inspecting image quality.

FIG. 1 is a configuration diagram of an image forming system according to one embodiment. FIG. 2 is a block diagram of a controller according to one embodiment. FIG. 2 is a configuration diagram of an inspection control unit according to an embodiment. FIG. 3 is a diagram showing an example of a screen displayed on an operation unit according to an embodiment. FIG. 3 is a diagram showing an example of a screen displayed on an operation unit according to an embodiment. An explanatory diagram of reflection. An explanatory diagram of reflection. A diagram showing an example of quantifying the degree of influence of reflection. An explanatory diagram of a method for determining the degree of influence of reflection. The figure which shows an example of a test chart. FIG. 2 is a diagram illustrating a test chart, according to one embodiment. FIG. 2 is a diagram illustrating a test chart, according to one embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the claimed invention. Although a plurality of features are described in the embodiments, not all of these features are essential to the invention, and the plurality of features may be arbitrarily combined. Furthermore, in the accompanying drawings, the same or similar components are designated by the same reference numerals, and redundant description will be omitted.

[Image forming system configuration]
FIG. 1 is a configuration diagram of an image forming system according to this embodiment. The operation unit 200 provides an input interface and an output interface with the user. The input interface is, for example, an input key, a touch panel, or the like. The output interface is, for example, a display, a speaker, etc. The operation unit 200 transmits instructions and data input by the user via the input interface to the controller 400. Furthermore, the operation unit 200 outputs information notified from the output interface according to instructions from the controller 400. The controller 400 controls the image forming apparatus 300, the inspection apparatus 500, the stacker 600, and the finisher 700 based on instructions and data input from the operation unit 200 or instructions and data acquired from an external device via the network. .

Image forming apparatus 300 includes image forming sections Y, M, C, and K. The image forming units Y, M, C, and K form yellow (Y), magenta (M), cyan (C), and black (K) images, respectively, and transfer them to the intermediate transfer body 306. By the image forming units Y, M, C, and K superimposing images of each color and transferring them to the intermediate transfer body 306, colors different from yellow, magenta, cyan, and black can be reproduced. The image forming units Y, M, C, and K have the same configuration and include a photoreceptor 301, a charger 302, an exposure device 303, and a developer 304. The photoreceptor 301 is rotated counterclockwise in the figure during image formation. The charger 302 uniformly charges the surface of the rotating photoreceptor 301. The exposure device 303 acquires image data from the controller 400 and forms an electrostatic latent image on the photoreceptor 301 by exposing the photoreceptor 301 to light according to the image data. The developing device 304 has toner of a corresponding color, and forms an image (toner image) on the photoreceptor 301 by developing the electrostatic latent image on the photoreceptor 301 with the toner.

As described above, the images formed by the image forming units Y, M, C, and K on each photoreceptor 301 are transferred to the intermediate transfer member 306. The intermediate transfer body 306 is rotated clockwise in the figure during image formation. Therefore, the image transferred to the intermediate transfer body 306 is conveyed to the transfer section 307. On the other hand, the recording media stored in the cassettes 311 and 312 are conveyed to the transfer unit 307 by rollers provided along the recording medium conveyance path. The transfer unit 307 transfers the image on the intermediate transfer body 306 to a recording medium. After the image is transferred, the recording medium is conveyed to a fixing device 308. The fixing device 308 fixes the image on the recording medium by heating and pressurizing the recording medium.

When an image is formed on only one side of the recording medium, after the image is fixed, the recording medium on which the image is formed, that is, the printed matter, is delivered to the inspection device 500 by the discharge roller 317. On the other hand, when forming images on both sides of the recording medium, after fixing the image formed on one side, the recording medium is again conveyed to the transfer unit 307 via the conveyance path 314 and the conveyance path 316, and then Image formation on the surface is performed. The recording medium with images formed on both sides is conveyed to the inspection device 500 after the images are fixed by the fixing device 308 .

In the inspection device 500, the printed material is conveyed on a conveyance path by conveyance rollers 504 and 505. The reading unit 501a reads an image on one side (first side) of the printed matter being conveyed to the reading position via the glass 502a. The reading unit 501b reads the image on the other side (second side) of the printed material being conveyed through the glass 502b. The reading sections 501a and 501b have a light emitting section and a light receiving section. The light emitting section includes, for example, a white LED (Light Emitting Diode). Further, the light receiving section includes a plurality of light receiving elements (pixels) capable of receiving each of red (R), green (G), and blue (B) light. As an example, the light receiving section is a CMOS sensor equipped with RGB color filters. Each pixel of the light receiving section receives reflected light emitted by the light emitting section and reflected by the printed material. The light receiving unit transmits inspection target data (RGB data), which is the reading result of the printed material, to the inspection control unit 510 based on the light reception result of each pixel. A backing 503a is provided on the opposite side of the glass 502a with respect to the conveyance path of the printed matter. Similarly, a backing 503b is provided on the opposite side of the glass 502b with respect to the conveyance path of the printed matter. The backings 503a and 503b are background members provided to fix the background color when the reading unit 501a and the reading unit 501b read the image of the printed matter.

The stacker 600 includes a large capacity tray 610 and a purge tray 620. The stacker 600 discharges printed matter to one of the large-capacity tray 610, the finisher 700, and the purge tray 620 based on instructions from the controller 400 and the results of quality inspection by the inspection control unit 510.

The finisher 700 has a function of performing post-processing such as stapling, binding, and cutting of printed matter according to instructions from the controller 400. The finisher 700 discharges the printed material to one of the paper discharge trays 710 to 730 according to instructions from the controller 400.

[Control configuration of image forming system]
FIG. 2 is a configuration diagram of the controller 400. In addition to the image forming apparatus 300, the inspection apparatus 500, the stacker 600, the finisher 700, and the operation section 200, the controller 400 is connected to a hard disk drive (HDD) 4100 and a power supply control section 4500. Note that in FIG. 2, the stacker 600 and finisher 700 are omitted for the sake of simplification. Power control unit 4500 controls power supply to the image forming system.

Each functional block within the controller 400 shown in FIG. 2 is connected to a bus 4319 or 4311. Bus I/F 4310 is a bridge that connects bus 4319 and bus 4311. The controller 400 includes a Central Processing Unit (CPU) 4301, a Read Only Memory (ROM) 4302, and a Random Access Memory (RAM) 4303.

The CPU 4301 controls the operation of the image forming system by executing a computer program stored in the ROM 4302. The RAM 4303 provides a work area when the CPU 4301 executes processing. The RAM 4303 is also used as an image memory for temporarily storing image data and the like. NVRAM 4304 stores various control parameters. A timer 4308 performs time management.

The operation unit I/F 4306 controls communication with the operation unit 200. The printer communication I/F 4307 controls communication with the image forming apparatus 300 under the control of the CPU 4301. The power supply control I/F 4308 instructs the power supply control unit 4500 to supply/stop various types of power according to commands from the CPU 4301. The inspection unit I/F 4317 controls communication with the inspection apparatus 500 under the control of the CPU 4301. The HDD I/F 4318 performs communication control with the HDD 4100 under the control of the CPU 4301.

A communication I/F 4305 is connected to a network such as a Local Area Network (LAN), and performs communication control such as sending and receiving e-mails and inputting and outputting PDL data from external devices. The compression unit 4312 performs compression and expansion processing such as JPEG, JBIG, MMR, and MH. The rotation unit 4313 performs image rotation processing. For example, the RIP 4314 develops PDL data received by the communication I/F 4305 from an external device into RIP data that is bitmap raster image data. RIP data is, for example, image data represented by RGB. When forming an image on a recording medium, RIP data is converted into image data corresponding to each color of YMCK, and the converted image data is sent to the image forming apparatus 300 by the printer I/F 4316. The image forming apparatus 300 forms an image on a recording medium using the method described above based on the transmitted image data.

FIG. 3 is a configuration diagram of the inspection control section 510. A CPU 5001, ROM 5002, RAM 5003, HDD I/F 5004, image processing unit 5008, determination unit 5006, RTC 5012, and host I/F 5007 are connected to the bus 5005 of the inspection control unit 510. The CPU 5001 controls the operation of the inspection apparatus 500 by executing a computer program stored in the ROM 5002. The RAM 5003 provides a work area when the CPU 5001 executes processing. The HDD I/F 5004 controls communication with the HDD 5011. The host I/F 5007 controls communication with the controller 400. For example, image data acquired by the host I/F 5007 from the controller 400 is stored in the HDD 5011. The RTC 5012 is a real-time clock and performs time management.

<Image position adjustment based on reading results>
In this embodiment, control is performed to adjust the position of the image formed by the image forming apparatus 300 based on the reading results of the reading units 501a and 501b. Specifically, for example, when a user uses the operation unit 200 to input an instruction to adjust the position of an image formed by the image forming apparatus 300, the controller 400 generates a position adjustment chart that is a predetermined test chart. The image forming apparatus 300 is controlled to form an image on a recording medium. As a result, the image forming apparatus 300 forms the position adjustment chart on the recording medium, and conveys the recording medium on which the position adjustment chart has been formed to the inspection apparatus 500. The reading units 501a and 501b of the inspection device 500 read the position adjustment chart. Note that the distance between the position on the recording medium where the image of the position adjustment chart is to be formed and the position of the edge of the recording medium is determined in advance to a predetermined value. The reading units 501a and 501b output the reading results of the position adjustment chart to the image processing unit 5008 via reading I/Fs 5052a and 5052b, respectively.

The image processing unit 5008 calculates the distance between the position of the edge of the recording medium in the image obtained by reading the position adjustment chart by the reading units 501a and 501b and the position of the image of the position adjustment chart. Furthermore, the image processing unit 5008 calculates a difference value between the calculated distance and the predetermined value, and transmits the difference value to the image forming apparatus 300. The image forming apparatus 300 adjusts the position of the image to be formed on the recording medium so that the difference value becomes small. That is, the image forming conditions for forming an image on the recording medium are reset so that the difference value becomes smaller. Note that the image of the position adjustment chart may be a registration mark (trim) mark, or a patch, for example.

Note that in this embodiment, a backing member with a high density (for example, black color) is used as the backings 503a and 503b. By using such a backing member, the position of the edge of the recording medium can be detected with high precision. As a result, the position of the image to be formed on the recording medium can be adjusted with high precision. Note that black in this embodiment means, for example, that the luminance values of each RGB color when the backing member is read by the reading units 501a and 501b are (R, G, B) = (0, 0, 0) to (50 , 50, 50).

<Image inspection based on reading results>
In this embodiment, the quality of the image formed by the image forming apparatus 300 is inspected based on the reading results of the reading units 501a and 501b. Specifically, for example, when a user uses the operation unit 200 to input an instruction to inspect the quality of an image formed by the image forming apparatus 300, the inspection apparatus 500 inspects the quality of an image formed on a recording medium by the image forming apparatus 300. Read the image. The inspection control unit 510 also acquires RIP data (details will be described later), which is the original data of the image data used to form the printed material, from the controller 400.

The image processing unit 5008 corrects the read data so as to reduce the influence of reflection included in the images read by the reading units 501a and 501b. Details will be described later.

The inspection control unit 510 has correction data indicating correction parameters. The correction parameter is a parameter for correcting error components included in the reading results by the reading units 501a and 501b, and is generated by calibration described later. Note that, as described above, the error component may include the difference between the color indicated by the RIP data and the color indicated by the inspection target data.

For example, the inspection control unit 510 corrects the read data (inspection target data) that has been corrected to reduce the influence of reflection using a correction parameter, and compares the corrected inspection target data with the RIP data to check the printed matter. Perform quality inspection. Note that the inspection control unit 510 may correct the RIP data using correction parameters.

Note that, as a quality inspection item for printed matter, for example, there is an inspection of the color tone of an image. The color test is performed, for example, based on the difference value between the R image data (luminance data) in the reference data and the R image data (luminance data) in the inspection target data. More specifically, if the difference value is greater than or equal to a predetermined value, it is determined to be "fail", and if the difference value is less than the predetermined value, it is determined to be "pass". Similar processing is performed for G and B, respectively.

As described above, in this embodiment, the reading units 501a and 501b are used for controlling the position of the image formed by the image forming apparatus 300 and for inspecting the quality of the image formed by the image forming apparatus 300. It will be done.

FIG. 4 shows an example of a print setting screen displayed on the display of the operation unit 200. The user can control the operation of the image forming apparatus 300 by operating the operation unit 200 based on the screen displayed on the display. For example, according to FIG. 4, the user can set the output destination of printed matter using button B104. Further, the user can select the size and paper type of the recording medium using the button B106. When button B102, which is a print start button, is pressed, controller 400 transmits image data to image forming apparatus 300 and causes image forming apparatus 300 to form an image. When button B103, which is a cancel button, is pressed, a predetermined initial screen is displayed on the display of operation unit 200. When button B105 is selected, the image forming apparatus 300 prints a test chart, which will be described later, and causes the inspection apparatus 500 to read the test chart, thereby generating correction parameters. When button B101 is selected, for example, an examination setting screen shown in FIG. 5 is displayed on the display.

The inspection setting screen shown in FIG. 5 is a screen for the user to make various settings when the inspection apparatus 500 performs a quality inspection. In area B401 of the inspection setting screen, an image to be inspected that is a target of quality inspection is displayed. Image data (RIP data) for forming an image to be inspected is stored in advance in the HDD 4100 of the image forming apparatus 300, for example. The user can set the inspection area by selecting the area B401 by touch operation while selecting the inspection area type buttons shown in buttons B402a to B402c. Note that the button B402a is a button for setting a region for performing a high-precision test, and the button B402b is a button for setting a region for performing a standard test. Further, button B402c is a button for setting an area where no inspection is performed.

Buttons B403a and B403b are buttons for setting the inspection level, that is, the accuracy of the inspection, in stages such as levels 1 to 5, for example. The user can set the inspection level for each area of buttons B402a and B402b. Button B405 is an inspection start button, and when the user selects this button, inspection printing processing is started. That is, the inspection device 500 reads the image of the printed matter formed by the image forming device 300, that is, the image to be inspected, generates inspection target data, and performs a quality inspection of the printed matter by comparing the data with reference data. Button B406 is a button for returning to the original screen, and when the user selects this button, the screen returns to the print setting screen shown in FIG. 4.

Next, "reflection" will be explained. FIG. 6 shows a state in which the surface 601a of a white recording medium on the reading unit 501a side is divided into a plurality of regions. Each region corresponds to one pixel of the light receiving section of the reading section 501a. Note that in FIG. 6, the sub-scanning direction corresponds to the conveyance direction of the recording medium, and the main scanning direction is a direction perpendicular to the conveyance direction of the recording medium. In an ideal state, one pixel of the light receiving section of the reading section 501a receives only the reflected light reflected from the corresponding area on the surface 601a. However, each pixel also receives reflected light reflected from a different area from the corresponding area. This situation is shown in FIG. In FIG. 7, a pixel of the reading unit 501a corresponding to the region of interest A on the surface 601a of the recording medium is referred to as a pixel of interest A.

As shown in FIG. 7, due to the difference between the refractive index of the glass 502a, which is a transparent member, and the refractive index of air, the light reflected in the region B and region C, which are different from the region of interest A, is reflected by the reflected light B in FIG. As shown as ' and C', the light propagates within the glass 502a and heads toward the region of interest A. Then, the reflected lights B' and C' reflected from the region of interest A enter the pixel of interest A as reflected light B'' and reflected light C''. Note that in FIG. 7, the reflected light A'' is the reflected light that is reflected only from the attention area A where the attention pixel A should originally receive light. Note that since the reflected light C' is reflected more times within the glass 502a than the reflected light B', the intensity of the reflected light C'' is weaker than the intensity of the reflected light B''. In FIG. 7, only the reflected light from areas B and C, which are at the same position in the sub-scanning direction as the area of interest A, is shown, but the pixel A of interest shows the reflected light from various areas around the area of interest A. Light also enters. Therefore, in addition to the necessary reflected light A'', unnecessary reflected light from the surrounding area also enters the pixel of interest A'', so that the amount of light received by the pixel of interest A increases, and "reflection" occurs.

FIG. 8 is a diagram illustrating numerically the degree of influence of reflection from the surrounding area of the region of interest corresponding to the pixel of interest. Note that the larger the numerical value, the greater the influence, and the area with the value "0" indicates that it is an area that does not have the effect of reflection on the pixel of interest. As shown in FIG. 8, the closer the distance to the region of interest corresponding to the pixel of interest is, the greater the influence of reflection becomes.

The degree of influence from the surrounding area of the region of interest shown in FIG. 8 is as shown in FIG. 9, where only the region of interest A is made white, the same as the surface 601a in FIG. This can be obtained by using a recording medium having 602a. In the recording medium of FIG. 9, the area different from the area of interest A is solid black, so the light that enters the pixel of interest A after being reflected in an area different from the area of interest A is more intense than in the case of the recording medium of FIG. 6. becomes smaller. Therefore, for example, if the amount of light received by the pixel A of interest in the recording medium of FIG. 6 is "260" and the amount of light received by the pixel of interest A of the recording medium of FIG. The amount increment is "10". Therefore, the degree of influence from the surrounding area of the attention area is determined to be 10/250=0.040. In this way, the degree of influence shown in FIG. 8 is a value that can be determined in advance, such as during the development stage.

The increase in the amount of light received by the pixel of interest shown in FIG. It can be obtained by integrating the amount over all the first regions. Note that since the amount of light received by a pixel corresponds to the brightness value, the "amount of light received" in this embodiment can be read as the "brightness value." Therefore, in the HDD 5011 shown in FIG. 3 or the ROM 5003 of the inspection control unit 510, information indicating the degree of influence from the surrounding area of the region of interest shown in FIG. 9 is stored in advance. The image processing unit 5008 in FIG. 3 calculates an increase in the amount of light received by the pixel of interest due to reflection based on information indicating the degree of influence from surrounding areas of the region of interest, and corrects the amount of light received by the pixel of interest. Thereby, the image processing unit 5008 corrects the inspection target data so as to reduce the influence of reflection included in the images read by the reading units 501a and 501b. Note that instead of performing processing to reduce the influence of reflection on the inspection target data, processing may be performed to add the influence of reflection to the reference data.

Next, a test chart formed by the image forming apparatus 300 upon pressing the button B105 in FIG. 4 will be described. FIG. 10 shows an example of a test chart. In the example of FIG. 10, a total of 48 patch images (hereinafter simply referred to as patches) are formed on the surface of the recording medium. Note that the colors and densities of the patches are different from each other.

FIG. 11 shows an example of a test chart according to this embodiment. In this embodiment, since the density of the backing 503 is high, patches with high density are arranged at the periphery (edge) of the recording medium, and the patches are arranged so that the density decreases as it approaches the center of the recording medium. There is. As shown in FIG. 8, the effect of reflection becomes greater as the distance from the region of interest becomes smaller. Therefore, as shown in FIG. 11, by arranging the patches on the test chart so that the difference between the density of the patch and the density of the surrounding area of the patch is small, the influence of reflection can be suppressed. Note that the density around the patch includes the density of the patches surrounding the patch and the density of the backing 503 adjacent to the patch.

In Figure 11, the patch with (R, G, B) = (0, 0, 0) is formed furthest from the center, and the patch with (R, G, B) = (255, 255, 255) is formed the furthest from the center. It is formed near the center, and the (R, Although a patch of G, B)=(128, 128, 128) is formed, this is not the case. For example, as shown in FIG. 12, among the plurality of patches formed on the recording medium, the upper left patch (patch at the reference position) is set to (R, G, B) = (0, 0, 0), and the Alternatively, the density of the patch may be gradually thinned in a counterclockwise spiral.

Furthermore, the group of high-density patches may include, for example, dummy patches and low-density patches. A patch with high density (dark patch) means, for example, that the brightness value of each RGB color when read by the reading units 501a and 501b is (R, G, B) = (0, 0, 0) to (80, 80). , 80). In addition, a patch with low density (light patch) is, for example, a luminance value of each RGB color when read by the reading units 501a and 501b (R, G, B) = (180, 180, 180) to (255 , 255, 255).

When button B105 in FIG. 4 is pressed, image forming apparatus 300 forms a test chart shown in FIG. 11. The inspection device 500 reads the image of the test chart using the reading units 501a and 501b. The CPU 5001 determines correction parameters based on the difference (or ratio) between the read data and the RIP data corresponding to the test chart. The correction parameters are used in the inspection print process when button B405 in FIG. 5 is pressed. In this manner, the image forming system has a first operation mode in which a test chart is formed on a recording medium to generate correction parameters, and a second operation mode in which an image to be inspected is inspected based on the correction parameters. The configuration is such that the user can specify the operating mode to be executed.

As described above, in this embodiment, a backing member with a high density (for example, black color) is used as the backing 503. By using such a backing member, the edge of the recording medium can be detected with high precision, and the position of the image to be formed on the recording medium can be adjusted with high precision. As a result, it is possible to suppress the relative position shift between the image to be inspected and the reference image, so it is possible to suppress a decrease in the ratio of "passes" to the number of inspections when the image to be inspected is inspected. . In this configuration, patches with high density on the test chart are placed at the periphery (edge) of the recording medium, and patches with lower density are placed closer to the center of the recording medium, thereby suppressing the effects of glare. This makes it possible to read a test chart based on the reading results, and the accuracy of correction parameters generated based on the reading results can be increased. As a result, it is possible to prevent the accuracy of inspecting the quality of an image formed on a recording medium from decreasing.

[Other embodiments]
The present invention provides a system or device with a program that implements one or more of the functions of the embodiments described above via a network or a storage medium, and one or more processors in the computer of the system or device reads and executes the program. This can also be achieved by processing. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

The invention is not limited to the embodiments described above, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the following claims are hereby appended to disclose the scope of the invention.

300: Image forming apparatus, 501a, 501b: Reading section, 400: Controller

Claims (8)

an image forming device that forms an image on a recording medium based on image data;
A reading means for reading the image formed on the recording medium conveyed from the image forming apparatus through a transparent member at a reading position in a conveyance direction in which the recording medium is conveyed, the reading means configured to illuminate the recording medium with light. The reading means includes a light emitting means that emits light, a sensor that receives light emitted by the light emitting means and reflected by the recording medium, and the reading means with respect to a conveyance path along which the recording medium is conveyed. a reading device comprising: a black background member provided at the reading position on the opposite side;
at least one processor;
An image forming system comprising:
The at least one processor includes:
controlling the image forming apparatus to form the test chart on a first recording medium based on the image data corresponding to the test chart that is a predetermined image;
Based on the first image data obtained by the reading device reading the image to be inspected formed on the second recording medium by the image forming device and the image data corresponding to the image to be inspected, Inspecting the inspection target image formed on a second recording medium;
configured to run
The test chart includes a plurality of light patch images and a plurality of dark patch images formed to surround the plurality of light patch images,
An image forming system, wherein each of the plurality of light patch images and the plurality of dark patch images have different densities. The at least one processor includes:
Generating correction data based on second image data obtained by the reading device reading the test chart formed on the first recording medium and the image data corresponding to the test chart. and,
correcting the first image data using the correction data;
Inspecting the inspection target image formed on the second recording medium based on the corrected first image data and the image data corresponding to the inspection target image;
The image forming system according to claim 1, wherein the image forming system is configured to perform the following. The at least one processor includes:
Generating correction data based on second image data obtained by the reading device reading the test chart formed on the first recording medium and the image data corresponding to the test chart. and,
correcting the image data corresponding to the image to be inspected using the correction data;
Inspecting the image to be inspected formed on the second recording medium based on the first image data and the image data corresponding to the corrected image to be inspected;
The image forming system according to claim 1, wherein the image forming system is configured to perform the following. The at least one processor includes:
controlling the image forming apparatus to form a second test chart, which is a predetermined image, on a third recording medium;
Detecting the position of an edge of the third recording medium based on third image data obtained by the reading device reading the second test chart formed on the third recording medium;
determining a difference value between a predetermined value and a distance between the detected edge position and the second test chart formed on the third recording medium;
configured to run
The image forming system according to claim 1, wherein the image forming apparatus sets image forming conditions for forming an image on the fourth recording medium based on the difference value. The image forming system includes:
Based on a first operation mode in which the test chart is formed on the recording medium to generate the correction data, and the first image data corrected by the correction data or the image data corresponding to the image to be inspected. and a second operation mode for inspecting the image to be inspected;
2. The first operation mode is executed when the first operation mode is specified by the user, and the second operation mode is executed when the second operation mode is specified by the user. Or the image forming system according to 3. The image forming system according to claim 2 or 3, wherein the correction data is generated based on a ratio between the second image data and the image data corresponding to the test chart. The image forming system according to claim 1, wherein the image forming apparatus forms the image based on data generated from the image data. The test chart is arranged on the surface of the recording medium on which an image is formed so that the density of the patch image decreases in a spiral shape from a reference position toward the center of the recording medium. The imaging system described.

Images