Image forming device and image forming method

Abstract

To provide an image forming device and an image forming method which can selectively achieve restriction on driving of the image forming device and prevention of delay of a timing of improving an image quality when a normal image forming process is not executed.SOLUTION: An image forming device (100) is provided with an image forming part (3), a first image forming processing part (51) and a second image processing part (52). When a preliminarily set execution condition is satisfied, the second image processing part (52) executes an image forming process for detection for making the image forming part (3) form an image for detection, which is used to adjust an image formation condition in the image forming part (3), on a region (A3) outside a printing region in a transferred subject (26). The second image processing part (52) starts the image forming process for detection during execution of a normal mage forming process, and then switches whether the image forming process for detection should be continued or not in accordance with a preliminarily set switching condition, when the normal image forming process is completed prior to the image forming process for detection.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus and an image forming method. [Background technology]

[0002] An electrophotographic image forming apparatus includes an image forming unit that forms an image on a transfer medium based on input image data. The image forming apparatus then executes a normal image forming process in which the image forming unit forms a print image on the transfer medium based on image data of the print target. During the normal image forming process, the image forming apparatus may also execute a detection image forming process that forms a detection toner image used to adjust image formation conditions in the image forming unit (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-293240 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the number of prints corresponding to the image data to be printed may be less than the number of prints required to form the detection toner image on the transfer medium. In this case, if the detection image formation process is continued after the normal image formation process is completed, the image forming device will operate when the normal image formation process is not being performed. On the other hand, if the detection image formation process is completed at the same time as the normal image formation process is completed, the timing for improving image quality will be delayed.

[0005] An object of the present invention is to provide an image forming apparatus and an image forming method that can selectively limit the drive of the image forming apparatus when normal image forming processing is not being performed and prevent delays in the timing of improving image quality. [Means for solving the problem]

[0006] According to one aspect of the present invention, an image forming apparatus includes an image forming unit, a first image processing unit, and a second image processing unit. The image forming unit forms an image on a transfer medium based on input image data. The first image processing unit executes a normal image forming process in which the image forming unit forms a print image based on image data of a print target in a predetermined print area on the transfer medium. The second image processing unit executes a detection image forming process in which the image forming unit forms a detection image used to adjust image formation conditions in the image forming unit in an area outside the print area on the transfer medium when a predetermined execution condition is satisfied. Furthermore, after starting the detection image forming process during execution of the normal image forming process, the second image processing unit switches whether to continue the detection image forming process in accordance with a predetermined switching condition when the normal image forming process ends before the detection image forming process.

[0007] According to another aspect of the present invention, an image forming method is executed by a processor of an image forming apparatus including an image forming unit that forms an image on a transfer medium based on input image data. The image forming method includes a first image processing step and a second image processing step. The first image processing step executes a normal image forming process in which the image forming unit forms a print image based on image data of a print target in a predetermined print area on the transfer medium. The second image processing step executes a detection image forming process in which the image forming unit forms a detection image used to adjust image formation conditions in the image forming unit in an area on the transfer medium outside the print area, when predetermined execution conditions are satisfied. Furthermore, the second image processing step starts the detection image forming process during execution of the normal image forming process, and then switches whether to continue the detection image forming process in accordance with a predetermined switching condition when the normal image forming process ends before the detection image forming process. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an image forming apparatus and an image forming method that can selectively realize drive restriction of the image forming apparatus when normal image forming processing is not being executed and prevention of delay in timing for improving image quality. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing the configuration of an image forming apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing the system configuration of the image forming apparatus according to the embodiment of the present invention. [Figure 3] FIG. 3 is a schematic diagram showing the configuration of the image forming unit of the image forming apparatus according to the embodiment of the present invention. [Figure 4] FIG. 4 is a bottom view showing the configuration of the intermediate transfer belt of the image forming apparatus according to the embodiment of the present invention. [Figure 5] FIG. 5 is a diagram schematically showing an example of a detection toner image formed on the intermediate transfer belt in the image forming apparatus according to the first embodiment of the present invention. [Figure 6] FIG. 6 is a flowchart showing an example of the condition adjustment process executed in the image forming apparatus according to the first embodiment of the present invention. [Figure 7] FIG. 7 is a flowchart showing another example of the condition adjustment process executed by the image forming apparatus according to the second embodiment of the present invention. [Figure 8] FIG. 8 is a diagram schematically showing an example of a detection toner image formed on an intermediate transfer belt in an image forming apparatus according to a second embodiment of the present invention. [Figure 9] FIG. 9 is a flowchart showing another example of the condition adjustment process executed in the image forming apparatus according to the third embodiment of the present invention. [Figure 10] FIG. 10 is a diagram schematically showing an example of a detection toner image formed on an intermediate transfer belt in an image forming apparatus according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Note that the following embodiment is an example of a specific embodiment of the present invention and does not limit the technical scope of the present invention.

[0011] [First embodiment] First, the configuration of an image forming apparatus 100 according to a first embodiment of the present invention will be described with reference to FIGS.

[0012] For ease of explanation, the vertical direction in the installation state where image forming apparatus 100 is usable (the state shown in FIG. 1) is defined as the up-down direction D1. Also, the front-to-back direction D2 is defined with the left side of image forming apparatus 100 on the paper surface shown in FIG. 1 as the front (front face). Also, the left-to-right direction D3 is defined with the front face of image forming apparatus 100 in the installation state as the reference point.

[0013] Image forming apparatus 100 is a multifunction peripheral that has multiple functions, such as a scanning function for reading an image from an original document, a printing function for forming an image based on image data, a fax function, and a copy function. Note that the present invention may also be applied to image forming apparatuses such as printers, fax machines, and copy machines that are capable of forming images using an electrophotographic method.

[0014] As shown in FIGS. 1 and 2, the image forming apparatus 100 includes an ADF (Auto Document Feeder) 1, an image reading unit 2, an image forming unit 3, a paper feeding unit 4, an operation display unit 5, a storage unit 6, and a control unit .

[0015] The ADF 1 transports documents to be scanned by the scanning function, and includes a document setting section, a plurality of transport rollers, a document holder, and a paper ejection section.

[0016] The image reading unit 2 realizes the scanning function and includes a document table, a light source, a plurality of mirrors, an optical lens, and a CCD (Charge Coupled Device).

[0017] The image forming unit 3 realizes the printing function. Specifically, the image forming unit 3 forms a color or monochrome image on a sheet fed from the paper feed unit 4 according to an electrophotographic method.

[0018] The paper feed unit 4 supplies sheets to the image forming unit 3. The paper feed unit 4 includes a paper feed cassette, a manual feed tray, and multiple transport rollers. The control unit 7 can set the sheet type of the sheets to be printed and stored in the paper feed cassette in advance in response to a user operation. In particular, if the paper feed unit 4 is provided with multiple paper feed cassettes, the sheet type can be set for each paper feed cassette.

[0019] The operation display unit 5 is a user interface of the image forming apparatus 100. The operation display unit 5 has a display unit such as a liquid crystal display that displays various information in response to control instructions from the control unit 7, and an operation unit such as operation keys or a touch panel that inputs various information to the control unit 7 in response to user operations.

[0020] The storage unit 6 is a nonvolatile storage device. For example, the storage unit 6 is a nonvolatile memory such as a flash memory. The storage unit 6 may be a solid state drive (SSD) or a hard disk drive (HDD).

[0021] The control unit 7 performs overall control of the image forming apparatus 100. As shown in FIG. 2, the control unit 7 includes a CPU 11, a ROM 12, and a RAM 13. The CPU 11 includes one or more processors that execute various types of arithmetic processing. The ROM 12 is a non-volatile storage device that stores in advance information such as control programs for causing the CPU 11 to execute various types of processing. The RAM 13 is a volatile or non-volatile storage device that is used as a temporary storage memory (work area) for the various types of processing executed by the CPU 11. The CPU 11 performs overall control of the image forming apparatus 100 by executing the various control programs that are stored in advance in the ROM 12.

[0022] The control unit 7 may be a control unit provided separately from a main control unit that performs overall control of the image forming apparatus 100. The control unit 7 may also be configured with an electronic circuit such as an integrated circuit (ASIC).

[0023] [Configuration of image forming unit 3] Next, the configuration of the image forming section 3 will be described with reference to Figures 1 to 4. Here, Figure 3 is a schematic diagram showing the configuration of multiple image forming units 20, intermediate transfer belt 26, and secondary transfer roller 27. Also, Figure 4 is a bottom view showing the configuration of photosensitive drum 31 of image forming unit 24, intermediate transfer belt 26, drive roller 26A, and secondary transfer roller 27.

[0024] 1, the image forming section 3 includes four image forming units 20, an optical scanning device 25, an intermediate transfer belt 26, a secondary transfer roller 27, a fixing device 28, and a paper discharge tray 29. As shown in FIGS. 2 and 3, the image forming section 3 also includes four first power sources 40, a second power source 45, and a detection section 46. The image forming section 3 forms a toner image based on input image data on the intermediate transfer belt 26, and transfers the toner image from the intermediate transfer belt 26 to a sheet.

[0025] The four image forming units 20 include image forming units 21 to 24. Image forming unit 21 (see FIG. 3) forms a Y (yellow) toner image. Image forming unit 22 (see FIG. 3) forms a C (cyan) toner image. Image forming unit 23 (see FIG. 3) forms an M (magenta) toner image. Image forming unit 24 (see FIG. 3) forms a K (black) toner image. As shown in FIGS. 1 and 3, the four image forming units 20 are arranged side by side in the order of yellow, cyan, magenta, and black from the front side of image forming apparatus 100 along the front-rear direction D2.

[0026] 3, each image forming unit 20 includes a photosensitive drum 31, a charging roller 32, a developing device 33, a primary transfer roller 34, and a drum cleaning unit 35. Each image forming unit 20 also includes a toner container 36 shown in FIG.

[0027] An electrostatic latent image is formed on the surface of the photosensitive drum 31. For example, the photosensitive drum 31 has a photosensitive layer made of amorphous silicon. The photosensitive drum 31 receives a rotational driving force supplied from a motor (not shown) and rotates in a drum rotation direction D4 shown in FIG. 3. As a result, the photosensitive drum 31 transports the electrostatic latent image formed on its surface.

[0028] A preset charging voltage is applied to the charging roller 32, which charges the surface of the photosensitive drum 31. For example, the charging roller 32 charges the surface of the photosensitive drum 31 to a positive polarity. The surface of the photosensitive drum 31 charged by the charging roller 32 is irradiated with light based on image data emitted from the optical scanning device 25. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 31.

[0029] The developing device 33 develops the electrostatic latent image formed on the surface of the photosensitive drum 31. The developing device 33 includes a pair of stirring members, a magnet roller, and a developing roller. The pair of stirring members stir the developer, which contains toner and a carrier, contained within the developing device 33. For example, the toner contained in the developer is positively charged due to friction with the carrier contained in the developer. The magnet roller draws up the developer stirred by the pair of stirring members and supplies the toner contained in the developer to the developing roller. The developing roller transports the toner supplied from the magnet roller to a position facing the photosensitive drum 31. Furthermore, the developing roller receives a preset development bias voltage and supplies the toner transported to the facing position to the photosensitive drum 31. As a result, toner is selectively supplied to an exposure area of ​​the photosensitive drum 31 irradiated with light emitted from the optical scanning device 25, thereby developing the electrostatic latent image formed on the surface of the photosensitive drum 31. The developing device 33 is supplied with toner from a toner container 36 .

[0030] Upon receiving a predetermined primary transfer current, the primary transfer roller 34 transfers the toner image formed on the surface of the photosensitive drum 31 onto the outer circumferential surface of the intermediate transfer belt 26. As shown in Fig. 3, the primary transfer roller 34 is disposed opposite the photosensitive drum 31 with the intermediate transfer belt 26 sandwiched therebetween. The intermediate transfer belt 26 is an example of a transfer-receiving body in the present invention.

[0031] The drum cleaning unit 35 removes the toner remaining on the surface of the photosensitive drum 31 after the toner image has been transferred by the primary transfer roller 34 .

[0032] The optical scanning device 25 emits light based on image data toward the surface of the photosensitive drum 31 of each image forming unit 20.

[0033] The intermediate transfer belt 26 is an endless belt member onto which the toner images formed on the surfaces of the photosensitive drums 31 of each image forming unit 20 are transferred. For example, the intermediate transfer belt 26 is made of a resin material such as polyimide. The intermediate transfer belt 26 is stretched with a predetermined tension by a drive roller 26A (see FIG. 3) and a tension roller 26B (see FIG. 3). The intermediate transfer belt 26 rotates in a belt rotation direction D5 shown in FIG. 3 when the drive roller 26A rotates due to a rotational driving force supplied from a motor (not shown). As a result, the intermediate transfer belt 26 transports the toner images transferred from each photosensitive drum 31 to a transfer position onto a sheet by a secondary transfer roller 27. After the toner images are transferred by the secondary transfer roller 27, the outer peripheral surface of the intermediate transfer belt 26 is cleaned by a belt cleaning unit 26C (see FIG. 3).

[0034] The secondary transfer roller 27 receives a preset secondary transfer current and transfers the toner image transferred onto the outer peripheral surface of the intermediate transfer belt 26 onto a sheet supplied from the paper feed unit 4. As shown in FIG. 3, the secondary transfer roller 27 is disposed opposite the drive roller 26A with the intermediate transfer belt 26 sandwiched therebetween.

[0035] 4, the size of the secondary transfer roller 27 in the axial direction (left-right direction D3) is smaller than the width (size in the left-right direction D3) of the intermediate transfer belt 26. Therefore, a non-contact area A3 (see FIG. 4) that does not come into contact with the secondary transfer roller 27 is generated on the outer circumferential surface of the intermediate transfer belt 26. The non-contact area A3 is an area on the outer circumferential surface of the intermediate transfer belt 26 outside the contact area A2 (see FIG. 4) that comes into contact with the secondary transfer roller 27, and includes the ends of the intermediate transfer belt 26 in the width direction.

[0036] The fixing device 28 fixes the toner image transferred onto the sheet by the secondary transfer roller 27 onto the sheet.

[0037] The sheet on which the toner image has been fixed by the fixing device 28 is discharged onto the paper discharge tray 29.

[0038] Of the four first power sources 40, first power source 41 (see FIG. 2) is a constant current power source that supplies the primary transfer current to the primary transfer roller 34 of the image forming unit 21. Of the four first power sources 40, first power source 42 (see FIG. 2) is a constant current power source that supplies the primary transfer current to the primary transfer roller 34 of the image forming unit 22. Of the four first power sources 40, first power source 43 (see FIG. 2) is a constant current power source that supplies the primary transfer current to the primary transfer roller 34 of the image forming unit 23. Of the four first power sources 40, first power source 44 (see FIG. 2) is a constant current power source that supplies the primary transfer current to the primary transfer roller 34 of the image forming unit 24. Each of the first power sources 40 supplies the primary transfer current set by the control unit 7 to the primary transfer roller 34. For example, the primary transfer current is a negative current.

[0039] The second power supply 45 is a constant current power supply that supplies the secondary transfer current to the secondary transfer roller 27. The second power supply 45 supplies the secondary transfer current set by the control unit 7 to the secondary transfer roller 27. For example, the secondary transfer current is a negative current.

[0040] The detection unit 46 is used to detect the density and position of a toner image transferred to the non-contact area A3 (see FIG. 4) on the outer circumferential surface of the intermediate transfer belt 26. For example, the detection unit 46 is a reflective photosensor including a light-emitting unit that emits light toward the non-contact area A3 of the intermediate transfer belt 26 and a light-receiving unit that receives light emitted from the light-emitting unit and reflected by the non-contact area A3 of the intermediate transfer belt 26. The detection unit 46 inputs an electrical signal corresponding to the density of the toner image to be detected to the control unit 7. Note that in the image forming apparatus 100, detection toner images (described below) may be formed in the non-contact areas A3 on both sides of the contact area A2 on the intermediate transfer belt 26, and two detection units 46 may be provided at positions capable of detecting the detection toner images formed in the non-contact areas A3 on both ends. In this case, the image formation conditions are adjusted based on the detection results by the two detection units 46 in the adjustment process (described below).

[0041] 3, the detection unit 46 is disposed downstream in the belt rotation direction D5 of the position where the toner image is transferred by the secondary transfer roller 27, and upstream in the belt rotation direction D5 of the position where the belt cleaning unit 26C cleans the outer circumferential surface of the intermediate transfer belt 26. Alternatively, the detection unit 46 may be disposed downstream in the belt rotation direction D5 of the photosensitive drum 31 of the image forming unit 24, and upstream in the belt rotation direction D5 of the position where the toner image is transferred by the secondary transfer roller 27.

[0042] [Configuration of control unit 7] Next, the configuration of the control unit 7 will be described with reference to FIG.

[0043] 2, the control unit 7 includes a first image processing unit 51, a second image processing unit 52, a detection processing unit 53, a count processing unit 54, and an adjustment processing unit 55. Specifically, a condition adjustment program for causing the CPU 11 to function as each of the above-mentioned processing units is stored in advance in the ROM 12 of the control unit 7. The CPU 11 then executes the condition adjustment program stored in the ROM 12 to function as each of the above-mentioned processing units.

[0044] The condition adjustment program may be recorded on a computer-readable recording medium such as a CD, DVD, or flash memory, and may be read from the recording medium and stored in a storage device such as the memory unit 6. In addition, some or all of the first image processing unit 51, the second image processing unit 52, the detection processing unit 53, the count processing unit 54, and the adjustment processing unit 55 may be configured using electronic circuits such as an application specific integrated circuit (ASIC).

[0045] The first image processing unit 51 executes a normal image forming process in which a print image based on image data of the print target is formed in a predetermined print area A1 (see FIG. 4) on the intermediate transfer belt 26 by the image forming unit 3. Specifically, the first image processing unit 51 controls the optical scanning device 25 based on the image data of the print target to form an electrostatic latent image corresponding to each color on the photosensitive drum 31 of each image forming unit 20 at a predetermined timing. As a result, in each image forming unit 20, the electrostatic latent image formed on the photosensitive drum 31 is developed into a toner image, and the toner images are sequentially transferred to the intermediate transfer belt 26. Thereafter, the color or monochrome image formed on the intermediate transfer belt 26 is transferred to a sheet by the secondary transfer roller 27, and the intermediate transfer belt 26 is cleaned by the belt cleaning unit 26C.

[0046] In the normal image forming process, the first image processing unit 51 controls the amount of laser light emitted by the optical scanning device 25 based on preset input / output characteristics and the image data. In the normal image forming process, the first image processing unit 51 also controls the development bias voltage in each image forming unit 20 to a value preset for that image forming unit 20. In the normal image forming process, the first image processing unit 51 also controls the charging voltage, the primary transfer current, the secondary transfer current of the secondary transfer roller 27, and the like in each image forming unit 20.

[0047] Furthermore, in the normal image forming process, the first image processing unit 51 sets the conveying speed (hereinafter referred to as "linear speed") of the intermediate transfer belt 26 to a speed preset for each print type depending on the sheet type (plain paper, thick paper, etc.) and print type (monochrome printing, color printing). For example, when the sheet type is thick paper, the first image processing unit 51 slows the linear speed compared to when the sheet type is plain paper. Furthermore, when the print type is color, the first image processing unit 51 slows the linear speed compared to when the print type is monochrome.

[0048] Furthermore, in the normal image forming process, the first image processing unit 51 executes a preset inter-sheet process during an inter-sheet period P0 (see FIG. 5) between a process of forming an image based on image data for one page on the intermediate transfer belt 26 and a process of forming an image based on image data for the next page on the intermediate transfer belt 26. For example, in the inter-sheet process, cleaning of the photosensitive drum 31 by the drum cleaning unit 35 is executed. Also, in the inter-sheet process, various types of image processing may be executed for image data corresponding to the next sheet in the normal image forming process.

[0049] The second image processing unit 52 executes a detection image formation process when preset execution conditions are satisfied. In the detection image formation process, a detection toner image X10 (an example of a detection image) used to adjust the image formation conditions in the image forming unit 3 is formed by the image forming unit 3 in a non-contact area A3 (see FIG. 4) outside a print area A1 (see FIG. 4) on the intermediate transfer belt 26. The print area A1 is an area inside a contact area A2 (see FIG. 4) on the outer circumferential surface of the intermediate transfer belt 26. For example, the print area A1 is an area on the outer circumferential surface of the intermediate transfer belt 26 that contacts a sheet of the largest size that can be used in the image forming apparatus 100.

[0050] In this embodiment, since the detection toner image X10 is formed in the non-contact area A3 (see FIG. 4), compared to a configuration in which the detection toner image X10 is formed in the contact area A2, there is no need to provide a cleaning unit that removes the detection toner image X10 adhering to the secondary transfer roller 27 from the secondary transfer roller 27, making it possible to simplify the configuration. On the other hand, the detection toner image X10 may be formed in an area outside the print area A1 (see FIG. 4) and inside the contact area A2 (see FIG. 4). In this case, however, the detection unit 46 is disposed downstream in the belt rotation direction D5 of the photosensitive drum 31 of the image forming unit 24 and upstream in the belt rotation direction D5 of the transfer position of the toner image by the secondary transfer roller 27.

[0051] Furthermore, the second image processing unit 52 sequentially forms, on the intermediate transfer belt 26, detection toner images X11 to X14 corresponding to the multiple colors corresponding to the multiple image forming units 20, as detection toner image X10, based on preset detection image data corresponding to each color. For example, the detection toner image X10 is a rectangular single-color image.

[0052] 5, the second image processing unit 52 sequentially forms a plurality of detection toner images X11 corresponding to K (black), a plurality of detection toner images X12 corresponding to C (cyan), a plurality of detection toner images X13 corresponding to M (magenta), and a plurality of detection toner images X14 corresponding to Y (yellow). Each of the detection toner images X11 is a K (black) toner image corresponding to a different preset density. Similarly, the detection toner images X12 to X14 are C (cyan), M (magenta), and Y (yellow) toner images corresponding to different preset densities.

[0053] Also, in this embodiment, for convenience of explanation, the width in the belt rotation direction D5 required to form a group of multiple detection toner images X11 is the same as the width of one page's worth of print area P1 in the image data to be printed. Similarly, for the detection toner images X12-X14, the width in the belt rotation direction D5 required to form the detection toner images X12-X14 is the same as the width of three pages' worth of print areas P2-P4 in the image data to be printed. Also, in the detection image forming process, the detection toner image X10 is not formed during the inter-sheet process. Therefore, in this embodiment, the number of pages required to form all of the detection toner images X11-X14 on the intermediate transfer belt 26 is "4." Therefore, when the detection image forming process is executed during the normal image forming process and the number of pages in the normal image forming process is "4" or less, the normal image forming process ends before the detection image forming process ends. In another embodiment, the width in the belt rotation direction D5 in which the detection toner images X11 to X14 are formed may exceed the print area of ​​one page of the image data to be printed.

[0054] In this embodiment, the execution condition is that the cumulative number of printed sheets in image forming apparatus 100 reaches a multiple of a predetermined first reference number. Alternatively, the execution condition may be that the number of printed sheets during execution of the normal image forming process reaches a multiple of a predetermined second reference number. Alternatively, the execution condition may be that the condition occurs at a predetermined time interval.

[0055] The detection processing unit 53 uses the detection unit 46 to detect the density and position of the detection toner image X10 formed in the non-contact area A3 of the intermediate transfer belt 26. Note that the detection processing unit 53 may detect only either the density or the position of the detection toner image X10. For example, if only the density correction process is performed in the adjustment process described below, it is sufficient to detect the density of the detection toner image X10, and if only the position deviation correction process is performed in the adjustment process described below, it is sufficient to detect the position of the detection toner image X10.

[0056] The count processing unit 54 executes a counting process to count the cumulative number of printed sheets in the image forming apparatus 100. The cumulative number of printed sheets counted in the counting process is used to determine the timing for executing the adjustment process by the adjustment processing unit 55. For example, the count processing unit 54 resets the count value to 0 each time the adjustment process is executed in the image forming apparatus 100. Note that the count processing unit 54 may also count the cumulative number of printed sheets for each printing type, such as color and monochrome.

[0057] The adjustment processing unit 55 executes an adjustment process for adjusting the image forming conditions based on the detection result by the detection processing unit 53. Specifically, the adjustment processing unit 55 executes a density correction process, a positional deviation correction process, and the like in the adjustment process.

[0058] In the density correction process, if the difference between the density of the detection toner image X10 detected by the detection processing unit 53 and a predetermined reference density is less than a predetermined threshold, the amount of light emitted by the optical scanning device 25 is adjusted as the image formation condition based on the difference. Furthermore, in the density correction process, if the difference between the density of the detection toner image X10 detected by the detection processing unit 53 and the reference density is equal to or greater than the threshold, the developing bias voltage is adjusted as the image formation condition based on the difference. For example, the reference density is the density of the detection toner image X10 detected during the previous adjustment of the image formation conditions. Note that the image formation conditions adjusted in the density correction process are not limited to the amount of light emitted by the optical scanning device 25 and the developing bias voltage. For example, the image formation conditions may include the input / output characteristics, the charging voltage, the primary transfer current, and the secondary transfer current.

[0059] In the positional deviation correction process, the image formation timing (light irradiation timing by the optical scanning device 25) by the image forming unit 20 of each color is adjusted based on the difference between the detection position of the detection toner image X10 detected by the detection processing unit 53 and a predetermined specific position.

[0060] However, the number of prints corresponding to the image data to be printed may be less than the number of prints required to form the detection toner image X10 on the intermediate transfer belt 26. In this case, if the detection image formation process is continued even after the normal image formation process has ended, the image forming apparatus 100 will operate when the normal image formation process is not being performed. On the other hand, if the detection image formation process is ended when the normal image formation process has ended, the timing for improving image quality will be delayed. In contrast, the image forming apparatus 100 according to this embodiment can selectively limit the operation of the image forming apparatus when the normal image formation process is not being performed and prevent a delay in the timing for improving image quality.

[0061] [Condition adjustment process] 6, the image forming method of the present invention will be described below along with an example of the procedure of the condition adjustment process executed by the control unit 7 in the image forming apparatus 100. Here, steps S11, S12, etc. represent the numbers of the processing procedures (steps) executed by the control unit 7. The control unit 7 starts executing the condition adjustment process when a normal image forming process is executed in which a print image is printed on a sheet based on image data to be printed.

[0062] <Step S11> In step S11, the second image processing unit 52 of the control unit 7 determines whether a preset execution condition is met. Specifically, the execution condition is that the cumulative number of printed sheets in the image forming apparatus 100, as counted by the count processing unit 54, reaches a multiple of a predetermined first reference number. For example, the first reference number is 100 or 200 sheets. If it is determined that the execution condition is met (S11: Yes), the process proceeds to step S12. If it is determined that the execution condition is not met (S11: No), the process proceeds to step S12.

[0063] <Step S12> In step S12, the control unit 7 determines whether or not it is within the inter-sheet period P0 in the normal image forming process. If it is determined that it is within the inter-sheet period P0 (S12: Yes), the process proceeds to step S13, and if it is determined that it is not within the inter-sheet period P0 (S12: No), the condition adjustment process ends.

[0064] The control unit 7 can determine that the timing to start the inter-sheet processing has arrived when irradiation of laser light from the optical scanning device 25 based on image data for one page of the print target has started and irradiation of laser light based on that image data has ended. Alternatively, the control unit 7 may determine that the timing to start the inter-sheet processing has arrived when a preset time has elapsed since irradiation of laser light from the optical scanning device 25 based on image data for one page of the print target has started. After the timing to start the inter-sheet processing arrives, the control unit 7 starts irradiation of laser light based on image data for the next page of the print target when the inter-sheet processing has ended or when a preset time has elapsed. Therefore, in step S12, the control unit 7 determines that the inter-sheet processing is being performed from the time it determines that the start timing of the inter-sheet processing has arrived until the inter-sheet processing has ended or until a preset time has elapsed (S12: Yes).

[0065] <Step S13> In step S13, the second image processing unit 52 of the control unit 7 executes a process of sequentially forming the detection toner images X11 to X14 on the intermediate transfer belt 26. Specifically, the second image processing unit 52 sequentially inputs the detection image data corresponding to the detection toner images X11 to X14 to the image forming unit 3 each time step S13 is executed while the first image processing unit 51 is executing the normal image formation process. As a result, as shown in FIG. 5, the detection toner images X11 to X14 based on the detection image data are sequentially formed in the non-contact area A3 of the intermediate transfer belt 26 in the image forming unit 3. Note that the second image processing unit 52 does not execute step S13 while the inter-sheet process is being executed (S12: Yes). Therefore, the detection toner images X11 to X14 are not formed on the intermediate transfer belt 26 while the inter-sheet process is being executed, as shown in FIG. 5.

[0066] <Step S14> In step S14, the detection processing unit 53 of the control unit 7 uses the detection unit 46 to detect the density and position of the detection toner image X10 formed on the intermediate transfer belt 26 in step S13, and stores the detected density and position in the storage unit 6. The detected density and position of the detection toner image X10 are used in the image formation condition adjustment process described below.

[0067] <Step S15> In step S15, the control unit 7 determines whether the normal image forming process has ended. Specifically, the control unit 7 determines that the normal image forming process has ended when the last print image in the normal image forming process has been formed on the intermediate transfer belt 26 and the inter-sheet process has ended. If it is determined that the normal image forming process has ended (S15: Yes), the process proceeds to step S21. If it is determined that the normal image forming process has not ended (S15: No), the process proceeds to step S16.

[0068] In another embodiment, instead of steps S14 to S15, the control unit 7 may determine that the normal image forming process will end before the detection image forming process ends if the number of sheets printed in the normal image forming process is four or less, which is the number required to execute the detection image forming process, and may transition to step S21.

[0069] <Step S16> In step S16, the control unit 7 determines whether the densities and positions of all of the detection toner images X11 to X14 formed in step S13 have been detected. For example, the control unit 7 determines that the densities and positions of all of the detection toner images X11 to X14 have been detected when it has detected the densities and positions of the same number of detection toner images X10 as a preset number of detection toner images X11 to X14. The control unit 7 may also determine that the densities and positions of all of the detection toner images X11 to X14 have been detected when a preset time required to detect the densities and positions of all of the detection toner images X11 to X14 has elapsed. If it is determined that the densities and positions of all of the detection toner images X11 to X14 have been detected (S16: Yes), the process proceeds to step S17. If it is determined that the densities and positions of all of the detection toner images X11 to X14 have not been detected (S16: No), the process returns to step S12.

[0070] <Step S17> In step S17, the adjustment processing unit 55 of the control unit 7 executes an adjustment process to adjust the image formation conditions in the image forming unit 3 based on the density and position of each of the detection toner images X11 to X14 detected in step S14. As a result, the adjustment contents in the adjustment process in step S17 are reflected in the normal image formation process and the detection image formation process executed after execution of step S17. As described above, the position deviation correction process, the density correction process, etc. are executed in the adjustment process.

[0071] <Step S18> In step S18, the control unit 7 determines whether the normal image formation process has been completed, similarly to step S15. If it is determined that the normal image formation process has been completed (S18: Yes), the condition adjustment process is terminated, and if it is determined that the normal image formation process has not been completed (S18: No), the process returns to step S11.

[0072] In this embodiment, the case where the adjustment process is performed in step S17 will be described as an example, but the adjustment process may be performed at any timing after the detection of the density and position of each of the detection toner images X11 to 14 in step S14. For example, part or all of the adjustment process may be performed between step S14 and step S15, or between step S15 and step S16.

[0073] As described above, when all of the detection toner images X11 to X14 are formed during the execution of the normal image forming process, the condition adjustment process is executed until the normal image forming process is completed.

[0074] <Step S21> On the other hand, if the detection image formation process is started during the execution of the normal image formation process and the normal image formation process ends before the detection image formation process (S16: No, S15: Yes), the process proceeds to step S21. Then, in step S21, the second image processing unit of the control unit 7 switches whether or not to continue the detection image formation process according to a preset switching condition. Here, if it is determined that the detection image formation process should be continued (S21: Yes), the process proceeds to step S22, and if it is determined that the detection image formation process should not be continued (S21: No), the condition adjustment process ends together with the normal image formation process.

[0075] For example, during the initial setup of the image forming apparatus 100, the control unit 7 sets whether or not to continue the detection image formation process when the normal image formation process ends before the detection image formation process in response to a user operation, and stores the setting in the storage unit 6. Then, in step S21, if the continuation of the detection image formation process when the normal image formation process ends before the detection image formation process is set to yes, it is determined that the detection image formation process is to be continued (S21: Yes). In other words, if the continuation of the detection image formation process when the normal image formation process ends before the detection image formation process is set to no (S21: No), the detection image formation process will end midway when the normal image formation process ends. In this case, the user's setting of whether or not to continue the detection image formation process is an example of a switching condition in the present invention.

[0076] Furthermore, if the content of the image data to be printed in the normal image formation process executed together with the condition adjustment process is a photograph or image with a high print rate, there is a high possibility that a photograph or image will also be printed in the next normal image formation process. Therefore, the second image processing unit 52 may switch, in the control unit S21, whether to continue the detection image formation process depending on the content of the image data to be printed. Specifically, if the content of the image data to be printed in the normal image formation process executed together with the condition adjustment process is a photograph or image, the second image processing unit 52 may determine to continue the detection image formation process. On the other hand, if the content of the image data to be printed in the normal image formation process executed together with the condition adjustment process is text, the second image processing unit 52 may determine not to continue the detection image formation process depending on the content of the image data. In this case, the content of the image data is an example of a switching condition in the present invention. Note that, if image data to be printed in the normal image formation process scheduled to be executed after the normal image formation process executed together with the condition adjustment process has been input, the second image processing unit 52 may switch, in the control unit S21, whether to continue the detection image formation process depending on the content of the image data.

[0077] In another embodiment, when it is determined that the detection image formation process should not be continued (S21: No), it is possible to set the non-execution flag to 1. Then, in step S11, the control unit 7 determines that the execution condition is met even when the non-execution flag is 1. As a result, even if the detection image formation process ends before the normal image formation process is executed, the detection image formation process and the adjustment process are executed when the next normal image formation process is executed, and delays in the timing of improving image quality are suppressed.

[0078] In another embodiment, if it is determined not to continue the detection image formation process (S21: No), a non-execution counter may be incremented by one. The non-execution counter indicates the number of times that the normal image formation process ends before the detection image formation process and the detection image formation process is not continued after the normal image formation process ends, and is reset when the adjustment process is executed. Then, in step S21, if the non-execution counter has reached a preset number of times, the control unit 7 determines to continue the detection image formation process. As a result, if the event of the detection image formation process ending before the normal image formation process is executed occurs a preset number of times, the detection image formation process and the adjustment process are executed, thereby suppressing delays in the timing of image quality improvement. Note that if it is determined to continue the detection image formation process, the detection toner images X11 to X14 may be formed from the beginning in the detection image formation process.

[0079] <Step S22> In step S22, the second image processing unit 52 of the control unit 7 controls the image forming unit 3 to continue driving the intermediate transfer belt 26 and the image forming units 20, etc., even after the normal image forming process is completed. As a result, the driving of the intermediate transfer belt 26 and the image forming units 20, etc., which would normally stop when the normal image forming process is completed, continues.

[0080] <Step S23> In step S23, the second image processing unit 52 of the control unit 7 determines whether or not it is within the inter-sheet period P0 during which the inter-sheet processing is being performed, assuming that the normal image formation processing is continuing. For example, the control unit 7 starts timing after image data corresponding to the last sheet in the normal image formation processing is transferred to the intermediate transfer belt 26 and the timing for performing the inter-sheet processing has passed, and determines whether or not it is the inter-sheet processing based on the measured time. If it is determined that it is within the inter-sheet period P0 (S23: No), the processing proceeds to step S24, and if it is determined that it is not within the inter-sheet period P0 (S23: Yes), the processing proceeds to step S25.

[0081] <Step S24> In step S24, the second image processing unit 52 of the control unit 7 continues to execute the detection image formation process started in step S13. For example, if a K (black) detection toner image X11 and a C (cyan) detection toner image X12 have been formed on the intermediate transfer belt 26 in parallel with the normal image formation process for two pages in step S13, the second image processing unit 52 forms a subsequent M (magenta) detection toner image X13 and Y (yellow) detection toner image X14 on the intermediate transfer belt 26 in step S24. Furthermore, in step S13, if a K (black) detection toner image X11, a C (cyan) detection toner image X12, and an M (magenta) detection toner image X13 are formed on the intermediate transfer belt 26 in parallel with the normal image formation process for three pages, the second image processing unit 52 forms a subsequent Y (yellow) detection toner image X14 on the intermediate transfer belt 26 in step S24.

[0082] <Step S25> In step S25, the detection processing unit 53 of the control unit 7 uses the detection unit 46 to detect the density and position of the detection toner image X10 formed on the intermediate transfer belt 26 in step S13, as in step S14, and stores the detected density and position in the memory unit 6.

[0083] <Step S26> In step S26, the detection processing unit 53 of the control unit 7 determines whether the densities and positions of all of the detection toner images X11 to X14 have been detected, similar to step S16. If it is determined that the densities and positions of all of the detection toner images X11 to X14 have been detected (S26: Yes), the process proceeds to step S27, but if it is determined that the densities and positions of all of the detection toner images X11 to X14 have not been detected (S26: No), the process returns to step S23.

[0084] <Step S27> In step S27, the second image processing unit 52 of the control unit 7 controls the image forming unit 3 to stop driving the intermediate transfer belt 26 and the image forming units 20.

[0085] <Step S28> In step S28, the adjustment processing unit 55 of the control unit 7 executes an adjustment process to adjust the image forming conditions in the image forming unit 3 based on the density and position of each of the detection toner images X11 to X14 detected in steps S14 and S25, etc. As described above, the adjustment process executes the positional deviation correction process, the density correction process, etc.

[0086] As described above, in the image forming apparatus 100, when the normal image formation process ends before the detection image formation process, it is possible to switch between continuing the detection image formation process and executing it. This makes it possible to prevent a delay in the timing of improving image quality when the detection image formation process continues, and when the detection image formation process does not continue, the operation of the image forming apparatus 100 when the normal image formation process is not being executed is limited.

[0087] [Second embodiment] Next, another example of the condition adjustment process executed in the image forming apparatus according to the second embodiment will be described with reference to Figures 7 and 8. Note that the configuration of the image forming apparatus 100 that will not be described here is the same as that of the first embodiment.

[0088] 7, in the condition adjustment process executed in the image forming apparatus 100 according to this embodiment, step S23 is omitted, and steps S24 to S25 are repeatedly executed until the densities and positions of all of the detection toner images X11 to X14 are detected (S26: No). That is, in the first embodiment, the formation of the detection toner image X10 is interrupted when the inter-sheet process is executed, but in the condition adjustment process according to this embodiment, the formation of the detection toner image X10 continues without interruption even during the inter-sheet period P0 when it is assumed that the normal image formation process is continuing.

[0089] Specifically, Fig. 8 shows an example in which only an image based on one page's worth of image data is formed in the printing area P1 of the intermediate transfer belt 26, and the normal image formation process ends after all of the detection toner image X11 has been formed in the printing area P1 of the intermediate transfer belt 26. In this case, as shown in Fig. 8, the remaining detection toner images X12 to X14 are formed on the intermediate transfer belt 26 in step S24. At this time, when the detection toner images X12 to X14 are formed in step S24, the formation of the detection toner image X10 is not interrupted at the timing of execution of the sheet interval process, so the detection toner images X12 to X14 are formed continuously. Therefore, it is possible to shorten the execution time of the detection image formation process.

[0090] [Third embodiment] Next, another example of the condition adjustment process executed in the image forming apparatus according to the third embodiment will be described with reference to Figures 9 and 10. Note that the configuration of the image forming apparatus 100 that will not be described here is the same as that of the first embodiment.

[0091] As shown in FIG. 9, in the condition adjustment process executed by the image forming apparatus 100 according to this embodiment, if it is determined in step S21 that the detection image formation process will not be continued (S21: No), the process proceeds to step S31.

[0092] <Step S31> In step S31, the second image processing unit 52 of the control unit 7 resets the formation history of the detection toner images X11-X14 in step S13. As a result, even if the detection toner images X11-X14 were partially formed in step S13, the detection toner images X11-X14 will be formed from the beginning in step S24. In this way, in the condition adjustment process according to this embodiment, if the normal image formation process ends before the detection image formation process, the detection image formation process is executed again and the detection toner images X11-X14 are formed under the same conditions, thereby improving the accuracy of the adjustment process.

[0093] Also, as in the second embodiment, step S23 is omitted in the condition adjustment process according to this embodiment. Therefore, steps S24 to S25 are repeatedly executed until the densities and positions of all of the detection toner images X11 to X14 are detected (S26: No). That is, in the first embodiment, the formation of the detection toner image X10 is interrupted when the inter-sheet period P0 is executed, but in the condition adjustment process according to this embodiment, the formation of the detection toner image X10 continues without interruption even during the inter-sheet period P0, which would be the case if the normal image formation process were continuing.

[0094] Specifically, FIG. 10 shows an example in which only an image based on one page of image data is formed in the printing area P1 of the intermediate transfer belt 26, and the normal image formation process is completed after all of the detection toner image X11 has been formed in the printing area P1 of the intermediate transfer belt 26. In this case, as shown in FIG. 10, in step S24, the detection toner images X11 to X14 are formed on the intermediate transfer belt 26 from the beginning. At this time, when the detection toner images X11 to X14 are formed in step S24, the formation of the detection toner image X10 is not interrupted at the timing of the execution of the sheet interval process, so the detection toner images X11 to X14 are formed continuously. Therefore, it is possible to shorten the execution time of the detection image formation process. It is also possible that step S23 is not omitted in other embodiments.

[0095] [Notes on the Invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0096] <Appendix 1> an image forming unit that forms an image on a transfer medium based on input image data; a first image processing unit that executes a normal image forming process in which a print image based on image data of a print target is formed in a predetermined print area on the transfer receiving body by the image forming unit; a second image processing unit that, when a preset execution condition is satisfied, executes a detection image forming process in which the image forming unit forms a detection image used for adjusting the image forming conditions in the image forming unit in an area outside the print area on the transfer object; and Equipped with the second image processing unit starts the detection image formation process during the execution of the normal image formation process, and then switches whether or not to continue the detection image formation process in accordance with a preset switching condition when the normal image formation process ends before the detection image formation process; Image forming device.

[0097] <Appendix 2> The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; Even when the detection image forming process is continued after the normal image forming process is completed, the detection image is not formed on the transfer medium during the inter-sheet period when the normal image forming process is continued. 2. The image forming apparatus according to claim 1.

[0098] <Appendix 3> The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; When the detection image forming process is continued after the normal image forming process is completed, the detection image is formed on the transfer medium during the inter-sheet period when it is assumed that the normal image forming process is continuing. 3. The image forming apparatus according to claim 1 or 2.

[0099] <Appendix 4> when the second image processing unit does not continue the detection image forming process after the normal image forming process is completed, the second image processing unit re-executes the detection image forming process from the beginning after the normal image forming process is completed. 4. The image forming apparatus according to claim 1.

[0100] <Appendix 5> The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; When the detection image forming process is executed again from the beginning after the normal image forming process is completed, the detection image is formed on the transfer object during the inter-sheet period on the assumption that the normal image forming process is continuing. 5. The image forming apparatus according to claim 4.

[0101] <Appendix 6> The second image processing unit When the normal image forming process is completed before the detection image forming process, and the detection image forming process is not continued after the normal image forming process is completed, The detection image forming process is executed when the next normal image forming process is executed. 6. The image forming apparatus according to any one of claims 1 to 5.

[0102] <Appendix 7> When an event occurs in which the normal image formation process is completed before the detection image formation process and the detection image formation process is not continued after the completion of the normal image formation process, the second image processing unit executes the detection image formation process after the completion of the normal image formation process. 7. The image forming apparatus according to any one of claims 1 to 6.

[0103] <Appendix 8> the second image processing unit switches whether or not to continue the detection image formation process when the normal image formation process ends before the detection image formation process, in accordance with a setting made by a user operation; 8. The image forming apparatus according to any one of claims 1 to 7.

[0104] <Appendix 9> the second image processing unit switches whether or not to continue the detection image forming process when the normal image forming process ends before the detection image forming process, depending on the content of the image data to be printed. 9. The image forming apparatus according to any one of claims 1 to 8.

[0105] <Appendix 10> a processor of an image forming apparatus having an image forming unit that forms an image on a transfer medium based on input image data, a first image processing step of executing a normal image forming process in which a print image based on image data of a print target is formed in a predetermined print area on the transfer medium by the image forming unit; a second image processing step of executing a detection image forming process in which, when a preset execution condition is satisfied, the image forming unit forms a detection image used for adjusting the image forming conditions in the image forming unit in an area outside the printing area on the transfer object; An image forming method that performs the above steps, In the second image processing step, after the detection image formation process is started during the execution of the normal image formation process, whether or not to continue the detection image formation process in the case where the normal image formation process ends before the detection image formation process is started is switched according to a preset switching condition. Image forming method. [Explanation of symbols]

[0106] 1 ADF 2 Image reading unit 3 Image forming unit 4 Paper feed section 5 Operation display section 6 Memory section 7 Control Unit 20 Image forming unit 25 Optical scanning device 26 Intermediate transfer belt 27 Secondary transfer roller 28 Fixing device 31 Photosensitive drum 32 Charging roller 33 Developing device 34 Primary transfer roller 35 Drum Cleaning Department 36 Toner container 40 1st power supply 45 2nd power supply 46 Detector 100 Image forming device

Claims

1. an image forming unit that forms an image on a transfer medium based on input image data; a first image processing unit that executes a normal image forming process in which a print image based on image data of a print target is formed in a predetermined print area on the transfer target by the image forming unit; a second image processing unit that, when a preset execution condition is satisfied, executes a detection image forming process in which the image forming unit forms a detection image used for adjusting the image forming conditions in the image forming unit in an area outside the print area on the transfer object; and Equipped with the second image processing unit starts the detection image formation process during the execution of the normal image formation process, and then switches whether or not to continue the detection image formation process in accordance with a preset switching condition when the normal image formation process ends before the detection image formation process; Image forming device.

2. The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; Even when the detection image forming process is continued after the normal image forming process is completed, the detection image is not formed on the transfer object during the inter-sheet period when it is assumed that the normal image forming process is continuing. The image forming apparatus according to claim 1 .

3. The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; When the detection image forming process is continued after the normal image forming process is completed, the detection image is formed on the transfer medium during the inter-sheet period when it is assumed that the normal image forming process is continuing. The image forming apparatus according to claim 1 .

4. when the second image processing unit does not continue the detection image forming process after the normal image forming process is completed, the second image processing unit re-executes the detection image forming process from the beginning after the normal image forming process is completed. The image forming apparatus according to claim 1 .

5. The second image processing unit During an inter-sheet period in which the print image is not formed on the transfer medium in the normal image forming process, the detection image is not formed on the transfer medium; When the detection image forming process is re-executed from the beginning after the normal image forming process is completed, the detection image is also formed on the transfer medium during the inter-sheet period when it is assumed that the normal image forming process is continuing. The image forming apparatus according to claim 4 .

6. The second image processing unit When the normal image forming process is completed before the detection image forming process, and the detection image forming process is not continued after the normal image forming process is completed, The detection image forming process is executed when the next normal image forming process is executed. The image forming apparatus according to claim 1 .

7. the second image processing unit executes the detection image formation process after the end of the normal image formation process when an event occurs in which the normal image formation process is completed before the detection image formation process and the detection image formation process is not continued after the end of the normal image formation process, the second image processing unit executes the detection image formation process after the end of the normal image formation process. The image forming apparatus according to claim 1 .

8. the second image processing unit switches whether or not to continue the detection image formation process when the normal image formation process ends before the detection image formation process, in accordance with a setting made by a user operation; The image forming apparatus according to any one of claims 1 to 7.

9. the second image processing unit switches whether or not to continue the detection image forming process when the normal image forming process ends before the detection image forming process, depending on the content of the image data to be printed. The image forming apparatus according to any one of claims 1 to 7.

10. a processor of an image forming apparatus having an image forming unit that forms an image on a transfer medium based on input image data, a first image processing step of executing a normal image forming process in which a print image based on image data of a print target is formed in a predetermined print area on the transfer receiving body by the image forming unit; a second image processing step of executing a detection image forming process in which, when a preset execution condition is satisfied, the image forming unit forms a detection image used for adjusting the image forming conditions in the image forming unit in an area outside the printing area on the transfer medium; An image forming method that performs the above steps, In the second image processing step, after the detection image formation process is started during the execution of the normal image formation process, whether or not to continue the detection image formation process in the case where the normal image formation process is completed before the detection image formation process is completed is switched according to a preset switching condition. Image forming method.

Images