JP2006333410A - Image forming apparatus and method of adjusting image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To relieve a load imposed on an operator attended with read adjustment of an image read section and print adjustment of a print section. <P>SOLUTION: The image forming apparatus includes: a scanner 200 for reading an image of an original placed on an original platen; and a printer 100 for executing printing on the basis of image data of the original obtained from the scanner 200. A main control section 401 executes the read adjustment of the image read section on the basis of image data of a reference chart included in adjustment image data obtained by consecutive reading of the reference chart by the scanner 200 and a test print sheet obtained by the printing at the printer 100 arranged in the subscanning direction on the original platen in this order and executes the print adjustment of the printer 100 on the basis of the image data of the test print sheet included in the adjustment image data and read by the scanner after the read adjustment of the scanner 200. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that includes an image reading unit and a printing unit, and performs adjustment for both, and a method for adjusting the image forming apparatus.

  In recent years, digital copying machines have been widely used as image forming apparatuses using an electrophotographic system. The digital copying machine includes an image reading unit and a printing unit. The image reading unit reads an image of a document, and the printing unit forms an image on the sheet as a visible image, that is, prints the image data. In such a digital copying machine, reading adjustment of an image reading unit and printing adjustment of a printing unit are performed after assembly in a factory. The detailed method is disclosed in Patent Document 1, for example.

  Here, a general case where the reading adjustment of the image reading unit is performed using a reference chart prepared in advance, and the adjustment of the printing unit is performed using a test print sheet obtained by printing on the printing unit Will be described.

  As shown in FIG. 13, the reference chart 1001 has a rectangular frame image formed on the entire sheet. As shown in FIG. 14, the test print sheet 1002 is a sheet in which a rectangular frame image is printed on the full sheet, like the reference chart 1001, and the image data of the test print pattern is printed by the printing unit to be adjusted. It was obtained by this. Note that the image of the test print pattern can normally use the same image as the image of the reference chart, and the image data is stored in, for example, the image forming apparatus.

  Reading adjustment of the image reading unit is performed based on image data obtained by reading the reference chart 1001 with the image reading unit. The print adjustment of the printing unit is performed based on the image data obtained by reading the test print sheet 1002 with the image reading unit. In the order of these two adjustments, first, reading adjustment of the image reading unit is performed, and then printing adjustment of the printing unit is performed. Therefore, when performing these adjustments, the operator first places the reference chart 1001 on the document table of the image forming apparatus, and operates the start button to cause the image reading unit to read the reference chart 1001. Then, after completion of the reading adjustment of the image reading unit in the image forming apparatus, a test print sheet 1002 that has been printed in advance or printed after completion of the reading adjustment is arranged on the document table, and the start button is operated. An operation of causing the image reading unit to read the test print sheet 1002 is performed.

  Hereinafter, the adjustment method of the image reading unit and the adjustment method of the printing unit will be specifically described. In the following description, the frame portion on the reading start end side in the sub-scanning direction in the rectangular frame image is referred to as the front frame portion, the frame portion on the reading rear end side is referred to as the rear frame portion, and the reading start end side in the main scanning direction. The frame portion is referred to as an upper frame portion, and the frame portion on the reading rear end side is referred to as a lower frame portion.

  In the reading adjustment of the image reading unit, for example, (A1) adjustment of reading magnification in the sub-scanning direction, (A2) reading tip position adjustment in the sub-scanning direction, and (A3) main scanning when the image reading unit reads an original image. Direction reading off-center adjustment is performed. Note that the reading magnification adjustment in the main scanning direction is already performed correctly in the image reading unit (image reading apparatus) alone, and is not performed here.

  For these adjustments, for example, a sheet (hereinafter simply referred to as a reference chart) on which an image of a reference chart for reading adjustment of the image reading unit shown in FIG. 13 is printed is used. That is, adjustment is performed using the image data of the reference chart 1001 obtained by reading the reference chart 1001 with the image reading unit.

  The reference chart 1001 has a rectangular frame image as shown in FIG. In the figure, P1 indicates the front end position of the front frame portion of the rectangular frame, P2 indicates the rear end position of the rear frame portion of the rectangular frame, P3 indicates the upper end position of the upper frame portion of the rectangular frame, and P4 indicates the rectangular shape. The lower end position of the lower frame part of the frame is shown.

  (A1) In the reading magnification adjustment in the sub-scanning direction, the sub-scanning direction in the image data of the reference chart 1001 is set so that the P1-P2 interval in the image data of the reference chart 1001 matches the specified interval stored in the memory in advance. Adjust the magnification.

  (A2) In the reading leading edge position adjustment in the sub-scanning direction, on the memory, the position P1 in the image data of the reference chart 1001 matches the prescribed reading leading edge position (reading start edge position) stored in the memory in advance. The image data of the reference chart 1001 is moved back and forth in the sub-scanning direction.

  (A3) In reading off-center adjustment in the main scanning direction, the reference chart 1001 is stored on the memory so that the position P3 and the position P4 in the image data of the reference chart 1001 coincide with the prescribed positions stored in the memory in advance. Are moved back and forth in the main scanning direction.

  In the printing adjustment of the printing section, (B1) printing magnification adjustment in the sub-scanning direction, (B2) printing magnification adjustment in the main scanning direction, (B3) printing off-center adjustment in the main scanning direction, and (B4) printing in the sub-scanning direction. The tip position is adjusted.

  For these adjustments, for example, a sheet (hereinafter referred to as a test print sheet) obtained by printing an image of a test print pattern for print adjustment of the printing unit shown in FIG. 14 by the printing unit itself is used. That is, adjustment is performed using the image data of the test print sheet 1002 obtained by reading the test print sheet 1002 by the image reading unit.

  The test print sheet 1002 has a rectangular frame image as shown in FIG. In the figure, P11 indicates the rear end position of the front frame portion of the rectangular frame, P12 indicates the front end position of the rear frame portion of the rectangular frame, P13 indicates the lower end position of the upper frame portion of the rectangular frame, and P14 is a rectangular shape. The upper end position of the lower frame part of the frame is shown.

  (B1) In the sub-scanning direction printing magnification adjustment, the magnification in the sub-scanning direction of the image data of the test print sheet 1002 is adjusted so that the P11-P12 interval coincides with a predetermined interval stored in the memory in advance.

  (B2) In the print magnification adjustment in the main scanning direction, the magnification in the main scanning direction of the image data of the test print sheet 1002 is adjusted so that the P13-P14 interval coincides with a predetermined interval stored in the memory in advance.

  (B3) In the print off-center adjustment in the main scanning direction, the image of the test print sheet 1002 is displayed on the memory so that the width W2 of the upper frame portion of the rectangular frame matches the specified print width stored in the memory in advance. Data is moved back and forth in the main scanning direction.

(B4) In the print leading edge position adjustment in the sub-scanning direction, the image of the test print sheet 1002 is displayed on the memory so that the width W1 of the front frame portion of the rectangular frame matches the specified print width stored in the memory in advance. Data is moved back and forth in the sub-scanning direction.
JP2005-10733 (published on January 13, 2005)

  In the above-described conventional configuration, when performing reading adjustment of the image reading unit and printing adjustment of the printing unit, the operator arranges the reference chart 1001 on the document table of the image forming apparatus, operates the start button, and operates the image reading unit. After completion of the reading adjustment, it is necessary to perform operations such as placement of the test print sheet 1002 on the document table and operation of the start button, and this adjustment work is troublesome.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus and an image forming apparatus adjustment method that can reduce a burden on an operator associated with reading adjustment of an image reading unit and printing adjustment of a printing unit.

In order to solve the above problems, an image forming apparatus of the present invention is based on an image reading unit that reads an image of a document placed on a document table, and image data of the document obtained from the image reading unit. In an image forming apparatus having a printing unit for performing printing, image reading is performed in this order on a reference chart arranged in the sub-scanning direction on the document table and a test print sheet obtained by a printing operation in the printing unit. Image reading unit adjustment means for performing reading adjustment of the image reading unit based on the image data of the reference chart in the adjustment image data obtained by the unit reading continuously,
And a printing unit adjusting unit configured to perform printing adjustment of the printing unit based on the image data of the test print sheet in the adjustment image data after the reading adjustment of the image reading unit.

  The image forming apparatus adjusting method according to the present invention includes an image reading unit that reads an image of a document placed on a platen, and printing that performs printing based on the image data of the document obtained from the image reading unit. In the adjustment method of the image forming apparatus provided with the image reading unit, the reference chart arranged in the sub-scanning direction on the document table and the test print sheet obtained by the printing operation in the printing unit in this order A reading step for continuously reading, an image reading unit adjustment step for adjusting the reading of the image reading unit based on the image data of the reference chart in the adjustment image data obtained in the reading step, and an image reading unit A printing unit adjustment step of performing printing adjustment of the printing unit based on the image data of the test print sheet in the adjustment image data after the reading adjustment. That.

  According to the above configuration, when performing the read adjustment of the image reading unit and the print adjustment of the printing unit, the operator can print the reference chart for the read adjustment of the image reading unit and the print on the document table of the image forming apparatus. It is only necessary to perform a simple operation such as simultaneously arranging the test print sheets for printing adjustment of the copies and turning on the start button for starting reading. That is, a series of troublesome procedures such as placement of the reference chart on the platen, turning on the start button for reading, turning on the test print sheet on the platen after waiting for completion of reading adjustment of the image reading unit, and turning on the start button for starting reading. There is no need to perform any operation. Therefore, it is possible to reduce the burden on the operator due to the reading adjustment of the image reading unit and the printing adjustment of the printing unit.

  In the reading adjustment of the image reading unit, for example, the magnification adjustment and the position adjustment of the read image are performed, and in the printing adjustment of the printing unit, for example, the printing magnification adjustment and the printing position adjustment are performed.

  In the image forming apparatus, the image data for adjustment is divided into image data of a reference chart and image data of a test print sheet, the former is supplied to the image reading unit adjusting unit, and the latter is supplied to the printing unit adjusting unit. It is good also as a structure provided with a means.

  According to the above configuration, since the image cutting unit separates the images individually from the adjustment image data including the image data of the reference chart and the image data of the test print sheet, the image reading unit adjustment unit and the printing unit adjustment unit Means that each adjustment operation can be appropriately performed based on necessary image data.

  The image forming apparatus includes a gradation adjustment unit, the reference chart includes a reading adjustment chart and a gradation adjustment chart, and the image reading unit adjustment unit includes an image of the reference chart of the adjustment image data. The image reading unit performs reading adjustment based on the image data of the reading adjustment chart included in the data, and the gradation adjusting unit includes the image data of the gradation adjusting chart included in the image data of the reference chart of the adjustment image data. The gradation may be adjusted based on the above.

  According to the above configuration, the reading adjustment of the image reading unit is performed based on the image data of the reading adjustment chart included in the image data of the reference chart, and the image of the gradation adjustment chart included in the image data of the reference chart Since gradation adjustment is performed based on the data, the operator performs an operation for gradation adjustment by placing a gradation adjustment chart on the document table in addition to the operation for reading adjustment of the image reading unit. There is no need to do such work. As a result, the burden on the operator in adjusting the image forming apparatus can be further reduced.

  In the above-described image forming apparatus, the test print sheet has an image indicating a reference position on the sheet that is a predetermined distance from the edge of the sheet to the inside of the sheet at both ends of the sheet in the main scanning direction. The electrostatic latent image formed on the photosensitive member is developed with a developer, and the developer image is transferred onto a sheet. The beam detector and a light beam on the photosensitive member with the beam detector as a reference position. The printing unit adjustment means has a printing magnification adjustment based on the measured distance between the reference positions on both sheets indicated by the image data of the test print sheet and the specified distance between the reference positions on both sheets. A correction value is calculated, and a virtual position of the beam detector with respect to the reference position on the sheet detector indicated by the image data of the test print sheet is obtained. The print position correction value is calculated from the ideal distance to the reference position on the sheet and the specified reference position on the sheet, the print magnification is adjusted based on the print magnification correction value, and the print position is determined based on the print position correction value. It is good also as a structure which adjusts.

  According to the above configuration, it is possible to read one test print sheet and adjust the printing magnification and the printing position in the printing unit based on the image data, so that the work associated with the adjustment of the printing unit is easy. It becomes.

  An image forming apparatus of the present invention includes an image reading unit that reads an image of a document placed on a document table, and a printing unit that performs printing based on the image data of the document obtained from the image reading unit. The printing unit develops the electrostatic latent image formed on the photosensitive member with a developer and transfers the developer image onto a sheet. The beam detector and the beam detector serve as a reference position on the photosensitive member. In an image forming apparatus having a light beam irradiating unit that irradiates a light beam, an image showing a reference position on the sheet that is a predetermined distance from the edge of the sheet to the inside of the sheet at both ends of the sheet in the main scanning direction Image data obtained by reading the test print sheet on which the image is read by the image reading unit, and the measured distance between the reference positions on both sheets indicated by the image data and the bases on both sheets The correction value of the printing magnification is calculated from the specified distance between the positions, the virtual position of the beam detector with respect to the reference position on the sheet side indicated by the image data of the test print sheet is obtained, and from this virtual position and this virtual position The print position correction value is calculated from the ideal distance to the reference position on the sheet and the specified reference position on the sheet, the print magnification is adjusted based on the print magnification correction value, and the print position is determined based on the print position correction value. It is characterized in that it is provided with a printing unit adjusting means for adjusting the above.

  The image forming apparatus adjusting method according to the present invention includes an image reading unit that reads an image of a document placed on a platen, and printing that performs printing based on the image data of the document obtained from the image reading unit. The printing section is for developing the electrostatic latent image formed on the photosensitive member with a developer and transferring the developer image onto a sheet. The beam detector and the beam detector are used as a reference. In an adjustment method of an image forming apparatus having a light beam irradiating unit that irradiates a photosensitive member with a light beam as a position, a predetermined distance is entered from the edge of the sheet to the inside of the sheet at both ends of the sheet in the main scanning direction A reading step for reading a test print sheet on which an image indicating the reference position on the sheet is formed, and an actually measured distance between the reference positions on both sheets indicated by the image data obtained in the reading step; The correction value of the printing magnification is calculated from the prescribed distance between the reference positions on the sheet, and the virtual position of the beam detector with respect to the reference position on the sheet on the beam detector side indicated by the image data of the test print sheet is obtained. Calculate the print position correction value from the ideal distance from the virtual position to the reference position on the sheet and the specified reference position on the sheet, adjust the print magnification based on the print magnification correction value, and based on the print position correction value And a printing section adjusting step for adjusting the printing position.

  According to the above configuration, it is possible to read one test print sheet and adjust the printing magnification and the printing position in the printing unit based on the image data, so that the work associated with the adjustment of the printing unit is easy. It becomes.

  As described above, in the image forming apparatus of the present invention, the reference chart arranged in the sub-scanning direction on the document table and the test print sheet obtained by the printing operation in the printing unit are arranged in this order in the image reading unit. Read adjustment of the image reading unit based on the image data of the reference chart in the adjustment image data obtained by continuously reading, and the adjustment for the adjustment after the reading adjustment of the image reading unit A printing unit adjustment unit that performs printing adjustment of the printing unit based on the image data of the test print sheet in the image data.

  As a result, when performing the reading adjustment of the image reading unit and the printing adjustment of the printing unit, the operator can adjust the reference chart for reading adjustment of the image reading unit and the printing adjustment of the printing unit with respect to the document table of the image forming apparatus. It is only necessary to perform a simple operation such as simultaneously placing a test print sheet and turning on a start button for reading. That is, a series of troublesome procedures such as placement of the reference chart on the platen, turning on the start button for reading, turning on the test print sheet on the platen after waiting for completion of reading adjustment of the image reading unit, and turning on the start button for starting reading. There is no need to perform any operation. Therefore, it is possible to reduce the burden on the operator due to the reading adjustment of the image reading unit and the printing adjustment of the printing unit.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to the drawings.
The image forming apparatus according to the present embodiment is a multifunction machine including a scanner as an image reading unit and a printer as a printing unit. As shown in the overall configuration diagram of FIG. 3, the multifunction machine 1 schematically includes an automatic document feeder 210, a scanner 200 (image reading unit), a printer 100 (printing unit), and a paper feed desk device 20. Yes.

  In the present embodiment, a scanner 200 is arranged on the upper part of the multifunction device 1, and a document table 209 made of transparent glass is provided on the upper surface of the scanner 200. An automatic document feeder 210 is arranged on the document table 209. In addition, a printer 100 is disposed below the scanner 200, and a sheet feeding desk device 20 is disposed below the printer 100.

  The automatic document feeder 210 is a device that automatically conveys a plurality of sheets (documents) set on the document set tray 211 one by one onto the document table 209.

  The scanner 200 is a device that scans and reads an image of a sheet placed on the document table 209. The scanner 200 of this embodiment is a color scanner. The scanner 200 includes a first scanning unit 201, a second scanning unit 202, an optical lens 203, and a CCD line sensor 204, which is a photoelectric conversion element, below the document table 209.

  The first scanning unit 201 includes an exposure lamp 205 that exposes the surface of the sheet, a first mirror 206 that reflects a reflected light image from the sheet in a predetermined direction, and the like. The second scanning unit 202 includes a second mirror 207 and a third mirror 208 that guide the reflected light from the sheet reflected from the first mirror 206 of the first scanning unit 201 to the CCD line sensor 204 that is a photoelectric conversion element. Has been. The optical lens 203 forms an image of the reflected light from the original on the CCD line sensor 204. The CCD line sensor 204 uses a three-line image sensor of R (red), G (green), and B (blue), and can read an image by separating it into three colors.

  Next, the configuration of the printer 100 and the configuration of each unit related to the printer 100 will be described.

  The printer 100 forms multicolor and single color images on a predetermined sheet (recording paper) in accordance with image data transmitted from the outside of the printer 100.

  The printer 100 has four image forming stations for handling color images. The image data handled in the printer 100 corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y).

  Therefore, as shown in FIG. 3, the printer 100 includes an exposure unit 10 (10a, 10b, 10c, 10d), a developing device 2 (2a, 2b, 2c, 2d), and a photosensitive drum (image carrier) 3 ( 3a, 3b, 3c, 3d), cleaner unit 4 (4a, 4b, 4c, 4d) and charger 5 (5a, 5b, 5c, 5d) so as to form four types of latent images corresponding to the respective colors. , Each image forming station is provided. Each image forming station is set so that a corresponds to black (K), b corresponds to cyan (C), c corresponds to magenta (M), and d corresponds to yellow (Y). Has been. If there is no need to distinguish between the image forming stations, they will be referred to as an exposure unit 10, a developing device 2, a photosensitive drum 3, a cleaner unit 4, and a charger 5 for the sake of simplicity.

  The printer 100 further includes a transfer conveyance belt unit 8, a fixing unit 12, a paper conveyance path S, a paper feed tray 19, paper discharge trays 15 and 33, an image processing board 300, a control circuit board 400, and the like. The image processing substrate 300 includes an image processing unit 301. The control circuit board 400 includes a main control unit (image reading unit adjustment unit, printing unit adjustment unit) 401, printer control unit 402, scanner control unit 403, γ adjustment unit (gradation adjustment unit) 501, and storage unit 600. Yes. Hereinafter, each unit of the printer 100 will be described.

  The photosensitive drum 3 is disposed at the substantially central portion of the printer 100. The charger 5 is a charging means for uniformly charging the surface of the photosensitive drum 3 to a predetermined potential. In addition to the charger type shown in FIG. 3, a contact type charging roller type or brush type is available. Used.

  The exposure unit 10 is a laser scanning unit (LSU) including, for example, an EL or LED writing head in which light emitting elements are arranged in an array, a laser irradiation unit, and a reflection mirror. The exposure unit 10 exposes the charged photosensitive drum 3 according to an input image, thereby forming an electrostatic latent image according to image data on the surface.

  The developing device 2 visualizes the electrostatic latent images formed on the respective photosensitive drums 3 with K, C, M, and Y toners. The cleaner unit 4 removes and collects toner remaining on the surface of the photosensitive drum 3 after development and image transfer.

  The transfer conveyance belt unit 8 disposed below the photosensitive drum 3 includes a transfer belt 7, a transfer belt drive roller 71, a transfer belt tension roller 72, a transfer belt driven roller 73, a transfer belt support roller 74, and a transfer roller 6 ( 6a, 6b, 6c, 6d) and a transfer belt cleaning unit 9.

  The transfer belt driving roller 71, the transfer belt tension roller 72, the transfer roller 6, the transfer belt driven roller 73, the transfer belt support roller 74, and the like stretch the transfer belt 7 and rotate it in the direction of arrow B.

  The transfer roller 6 is rotatably supported by a frame (not shown) inside the transfer belt unit, and transfers the toner image on the photosensitive drum 3 to a sheet conveyed by being attracted to the transfer belt 7. Is.

  The transfer belt 7 is provided so as to be in contact with each photosensitive drum 3. Then, the toner images of the respective colors formed on the photosensitive drum 3 are sequentially transferred onto the sheet on the transfer belt 7. As a result, a color toner image (multicolor toner image) is formed on the sheet.

  Transfer of the toner image from the photosensitive drum 3 to the sheet is performed by the transfer roller 6 that is in contact with the back side of the transfer belt 7. A high voltage (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the transfer roller 6 in order to transfer the toner image. For example, a brush or the like can be used instead of the transfer roller 6.

  Thus, each member of the transfer / conveyance belt unit 8 functions as a transfer unit that transfers the toner image from the photosensitive drum 3 to the sheet.

  The toner adhering to the transfer belt 7 due to contact with the photosensitive drum 3 causes the back surface of the sheet to become dirty, and is removed and collected by the transfer belt cleaning unit 9.

  The paper feed tray 19 is a tray that stores sheets used for image formation, and is provided below the printer 100. A paper discharge tray 15 provided in the upper part of the printer 100 is a tray for placing printed sheets face down. A paper discharge tray 33 provided on the side of the printer 100 is a tray for placing sheets with images formed face up.

  The printer 100 is provided with an S-shaped paper conveyance path S for sending sheets from the paper feed tray 19 to the paper discharge tray 15 via the sheet transfer conveyance unit 8 and the fixing unit 12. Further, in the vicinity of the sheet conveyance path S from the sheet feed tray 19 to the sheet discharge tray 15 and the sheet discharge tray 33, a pickup roller 16, a registration roller 14, a fixing unit 12, a conveyance direction switching gate 34, and a conveyance for conveying a sheet. A roller 25 and the like are arranged.

  The conveyance rollers 25 are small rollers for promoting and assisting conveyance of the sheet, and a plurality of conveyance rollers 25 are provided along the sheet conveyance path S. The pickup roller 16 is provided at an end portion of the paper feed tray 19 and is a drawing roller that feeds sheets one by one from the paper feed tray 19 to the paper transport path S.

  The conveyance direction switching gate 34 is configured to separate the sheet from the middle of the conveyance path S and to discharge the sheet to the sheet discharge tray 33 by changing the state indicated by the solid line to the state indicated by the broken line. In the state indicated by the solid line, the sheet passes through the conveyance unit S ′ (part of the sheet conveyance path S) formed between the fixing unit 12, the side cover 35, and the conveyance switching guide (gate) 34, and is discharged at the top. It is discharged to the paper tray 15.

  The registration roller 14 temporarily holds the sheet being conveyed on the sheet conveyance path S. The sheet has a function of transporting the sheet with good timing in accordance with the rotation of the photosensitive drum 3 so that the toner image on the photosensitive drum 3 can be satisfactorily transferred onto the sheet.

  The fixing unit 12 includes a heat roller 31, a pressure roller 32, and the like. The heat roller 31 and the pressure roller 32 rotate while sandwiching the sheet, and the sheet is thermocompression bonded to melt, mix, and press the multicolor toner image transferred to the sheet, and thermally fix the sheet.

  The image processing board 300 is a circuit board that performs predetermined processing on image data, and the control circuit board 400 is a circuit board that controls an image forming process.

  Next, the sheet feeding desk device 20 will be described. The paper feed desk device 20 is provided below the paper feed tray 19 of the printer 100. The paper feed desk device 20 includes three stages of paper feed trays 20a to 20c, and can supply paper to the printer 100 via the paper transport path S. The multi-function device 1 according to the present embodiment is not limited to the configuration of the paper feed desk device 20, and includes a single-stage paper feed tray or a tandem tray that includes two trays in parallel. Alternatively, it can be mounted according to the user's request, such as a device that simply functions as a desk.

  In this embodiment, the printer 100 is described as a multicolor printer that forms a multicolor image. However, a printer that forms a monochrome (black and white) image can perform functions other than a part of the present invention. To do. Further, although the multi-function device 1 has been described as including the automatic document feeder 210, the present invention is not limited to this, and the automatic document feeder may not be mounted.

  The multifunction device 1 also includes an operation panel as a user interface of the multifunction device 1 at the position of the scanner 200. As shown in FIG. 4, a touch panel liquid crystal display device (referred to as LCD) 221 is arranged on the left side of the operation panel 220, and a numeric key 231, a start key 241, a clear key 251, and all keys are arranged on the right side thereof. A release key 261 is arranged.

  Various screens are switched and displayed on the screen of the LCD 221. In these screens, touch keys for setting various conditions are arranged, and various condition settings (for example, monochrome / color mode selection, document type selection, automatic selection are performed by directly pressing the touch keys with a finger. / Manual selection, other special function selection, etc.). In addition, operation guidance, warnings, and the like are also displayed on the LCD 221.

  Between the LCD 221 and the numeric keypad 231, as keys for switching functions when the multifunction device 1 having the printer 100 operates as a multifunction device, a printer key 271, a facsimile / image transmission key 281, a copy key 291, and the like, respectively. A job key 311 for confirming the job status registered for each function is arranged.

  Among the keys arranged on the right side of the LCD 221, the numeric keypad 231 is a key used for inputting a numerical value (such as the number of copies) on the LCD 221 screen, and the start key 241 is an image forming operation or reading in each processing mode. This is a key for instructing the start of operation. The clear key 251 is a key for clearing a set value displayed on the LCD 221 or interrupting an operation currently being executed such as an image forming operation. The all cancel key 261 is a reading condition, an image forming condition, or the like. It is a key to return the setting of to the default value. The interrupt key 321 is a key for temporarily interrupting an image forming operation being executed and allowing other image formation.

  FIG. 1 is a block diagram illustrating a main part of a functional configuration of the multifunction machine 1. As shown in the figure, the multifunction device 1 includes a main control unit 401 that controls the entire multifunction device 1, a printer 100, a printer control unit 402 that controls the printer 100, a scanner 200, and a scanner control unit 403 that controls the scanner 200. An image processing unit 301, a γ adjustment unit 501, and a storage unit 600. The storage unit 600 includes an image data storage unit 601, a reference data storage unit 602, and a test print pattern storage unit 603.

  The image data storage unit 601 stores image data read by the scanner 200. The image data storage unit 601 serves as a work area for the main control unit 401. The reference data storage unit 602 stores various reference values necessary for reading adjustment of the scanner 200 and printing adjustment of the printer 100. For example, the vertical and horizontal lengths of sheets of various sizes including A4 size are stored as reference values. The test print pattern storage unit 603 stores a test print pattern for printing a test print sheet 702 having at least one size including, for example, A4 size.

  FIG. 2 is a block diagram showing the main part of the functional configuration of the main control unit 401 shown in FIG. As shown in the figure, the main control unit 401 includes an image first cut unit (image cut unit) 411, an image second cut unit 421, a reading adjustment unit 431, and a print adjustment unit 441.

  As shown in FIG. 8, the first image segmentation unit 411 reads image data (reference chart image) of the reference chart 701 from an image obtained by simultaneously reading the reference chart 701 and the test print sheet 702 by the scanner 200. ) And image data of the test print sheet 702 (test print image). The reference chart image obtained in this way is input to the image second cut section 421, and the test print image is input to the print adjustment section 441.

  From the reference chart image, the image second cut-out unit 421 includes a reading adjustment image (an image of the reading adjustment chart 711 shown in FIG. 5) that is a rectangular frame-shaped image and an image inside the reading adjustment image. A certain γ adjustment chart image (image of the γ adjustment chart 712 shown in FIG. 5) is cut out. The read adjustment image obtained in this way is input to the read adjustment unit 431, and the γ adjustment chart image is input to the γ adjustment unit 501.

  The read adjustment unit 431 performs read adjustment of the scanner 200 based on the read adjustment image, the print adjustment unit 441 performs print adjustment of the printer 100 based on the test print image, and the γ adjustment unit 501 generates the γ adjustment chart image. Based on this, the gamma adjustment of the scanner 200 is performed.

  In the present embodiment, it is assumed that the reading magnification of the scanner 200 in the main scanning direction has already been correctly adjusted. This is because the magnification in the main scanning direction of the scanner 200 is mechanically adjusted by a jig or the like during assembly at the factory.

  FIGS. 5A and 5B are explanatory diagrams showing a reference chart and a test print sheet used in the multifunction machine 1 of the present embodiment. That is, in the present embodiment, the reference chart 701 shown in FIG. 5A is used instead of the reference chart 1001 shown in FIG. 13, and FIG. 5B is used instead of the test print sheet 1002 shown in FIG. The test print sheet 702 shown in FIG.

  The reference chart 701 has a γ adjustment chart (tone adjustment chart) 712 that is an image used for γ adjustment inside a reading adjustment chart 711 (corresponding to the reference chart 1001) made of a rectangular frame-shaped image. It has become a thing. Accordingly, the reference chart 701 can be used for reading adjustment and γ adjustment of the scanner 200.

  The test print sheet 702 is obtained by printing the test print pattern image data stored in the test print pattern storage unit 603. The image (test print pattern) of the test print sheet 702 is not a continuous rectangular frame-shaped image like the image of the test print sheet 102 but an image in which the frame-shaped portion image is partially thinned out. ing. As a result, the test print sheet 702 (test print pattern) can reduce the amount of toner used when it is printed.

  FIG. 6 is an explanatory diagram showing the relationship between the test print pattern stored in the test print pattern storage unit 603 and the test print sheet 702 on which the test print pattern is printed. Specifically, for example, a state in which a test print pattern image 751 formed based on the test print pattern is transferred from the photosensitive drum 3 to an area including the test print sheet 702 on the transfer belt 7 is shown. Alternatively, the correspondence between the test print pattern image 751 formed on the surface of the photosensitive drum 3 based on the test print pattern and the test print sheet 702 on the transfer belt 7 when the test print pattern image 751 is printed is shown. ing.

  As shown in the figure, the test print pattern printed on the test print sheet 702 is larger than the paper size of the test print sheet 702, so that the test print image is filled up to the end edge portion of the test print sheet 702. Can be printed. In the present embodiment, the size of the test print sheet 702 is A4.

  The test print sheet 702 (test print pattern) has a direction mark 731 inside the frame image 721. The direction mark 731 serves as a mark in the direction of the test print sheet 702 when the operator places the test print sheet 702 on the document table 209 or the like.

  5A and 5B are perspective views, and the reference chart 701 and the test print sheet 702 placed on the document table 209 with the surface on which the image is printed face down are displayed on the document table 209. It is a figure of the state seen through from the top. This also applies to the following drawings.

  In the above configuration, a reading adjustment method of the scanner 200 and a printing adjustment method of the printer 100 in the multifunction machine 1 of the present embodiment will be described below based on the flowchart of FIG.

  When the above adjustment is performed in the multifunction device 1, first, a test print sheet 702 is prepared (S1). For example, the test print sheet 702 is obtained by printing what is stored in advance in the test print pattern storage unit 603 by the printer 100.

  Next, as shown in FIG. 8, a reference chart 701 and a test print sheet 702 are arranged on the document table 209 in the sub-scanning direction (scanning direction of the exposure lamp 205) so as to be scanned in this order. It arranges on 209 (S2).

  In this case, both are arranged on the document table 209 with the document placement guide 101 as a reference. Specifically, the document placement guide 101 includes a front guide portion 111 that extends in the main scanning direction at a starting end position of document scanning (scanning in the sub-scanning direction) on the document table 209 and the multifunction device 1 on the document table 209. At the back side position, there is an upper guide portion 112 extending in the document scanning direction (sub-scanning direction) at a right angle to the front guide portion 111. Therefore, the reference chart 701 is arranged at the corner of the document placement guide 101 so as to be guided by the front guide part 111 and the upper guide part 112, and the reference chart 701 is guided only by the upper guide part 112, and for example, the reference chart 701 and an appropriate interval.

  FIG. 8 is an explanatory diagram showing a state in which the reference chart 701 and the test print sheet 702 are placed on the document table 209 by a perspective state of the printing surface of the reference chart 701 and the test print sheet 702.

  Next, when the start key 241 (corresponding to the reading start button) of the operation panel 220 is turned on (S3), the scanner 200 continuously scans the reference chart 701 and the test print sheet 702 and reads these images ( S4). The image data obtained thereby is input to the main control unit 401 via the image processing unit 301, and the main control unit 401 performs arithmetic processing on the image data (S5) and writes it in the image data storage unit 601.

  Next, in the main control unit 401, the image data of the reference chart 701 (reference chart image) and the image data of the test print sheet 702 (reference data) in the image data stored in the image data storage unit 601 by the first image cutout unit 411. The test print image) is separated (S6). Then, the image first cut unit 411 outputs the reference chart image to the image second cut unit 421, and outputs the test print image to the print adjustment unit 441.

  Next, the main control unit 401 performs reading adjustment of the scanner 200 and γ adjustment of the scanner 200 based on the inputted reference chart image (S7).

  Next, the main control unit 401 performs print adjustment of the printer 100 based on the input test print image (S8).

  Thereafter, the main control unit 401 feeds back various adjustment values obtained by the reading adjustment and the print adjustment to the scanner control unit 403 and the printer control unit 402 (S9).

  In the present embodiment, the print adjustment of the printer 100 needs to be performed based on the image data of the test print sheet 702 read by the scanner 200 after the read adjustment of the scanner 200 is completed. Therefore, the reading adjustment of the scanner 200 is preferably completed before the reading of the test print sheet 702 is started when the reference chart 701 and the test print sheet 702 are successively read in this order. . If the reading adjustment of the scanner 200 is not completed before the reading of the test printing sheet 702 is started, the reading operation by the scanner 200 is performed again after the reading adjustment of the scanner 200 is completed, and the test printing sheet 702 obtained thereby is read. The print adjustment of the printer 100 may be performed based on the image data.

  Next, reading adjustment and γ adjustment of the scanner 200 in S7 shown in FIG. 7 will be described based on the flowchart of FIG.

  In the reading adjustment of the scanner 200, in the main control unit 401, the image second cut-out unit 421 includes a reading adjustment image that is a rectangular frame-shaped image from the reference chart image and an image inside the reading adjustment image. A certain γ adjustment chart image is cut out (S11). Then, the second image cutout unit 421 outputs the read adjustment image to the read adjustment unit 431 and outputs the γ adjustment chart image to the γ adjustment unit 501.

The γ adjustment unit 501 performs γ adjustment of the scanner 200 based on the γ adjustment chart image (S12). This γ adjustment is performed by a known method. On the other hand, the reading adjustment unit 431 performs reading adjustment of the scanner 200 based on the reading adjustment image (S13 to S14).
In the γ adjustment, for example, when the color data of the read reference chart image is A1, and the color data when this is corrected with the initial color correction coefficient B1 is A2, the reference values Aref and A2 are compared. If the allowable range is exceeded, the color correction coefficient is changed so as to be within the allowable range. Thereby, the output color data is made close to the reference value.

  In the reading adjustment of the scanner 200, the reading adjustment unit 431 first adjusts the magnification of the read image in the sub-scanning direction (S13). Next, the reading adjustment unit 431 adjusts the tip position in the sub-scanning direction (S14). Finally, the reading adjustment unit 431 performs off-center adjustment in the main scanning direction (S15). The details of the reading adjustment of the scanner 200 are as described above based on FIG.

  Next, the print adjustment of the printer 100 in S8 shown in FIG. 7 will be described based on the flowchart of FIG.

  In the print adjustment of the printer 100, the print adjustment unit 441 of the main control unit 401 first detects the arrangement direction and size of the test print sheet 702 on the document table 209 from the test print image input from the scanner 200 (S21). ).

  Next, a calculation for adjusting the printing position is performed (S22), and then a calculation for adjusting the printing magnification is performed (S23). The process of S23 corresponds to the above-described (B1) print magnification adjustment in the sub-scanning direction and (B2) print magnification adjustment in the main scanning direction. Next, the printing off-center adjustment in the main scanning direction is performed (S24), and then the printing leading edge position adjustment in the sub scanning direction is performed (S25). The details of the print adjustment of the printer 100 are as described above based on FIG. 14 although there are differences between the test print sheet 702 and the test print sheet 1002 as test print sheets to be used.

  As described above, in the adjustment method of the multifunction peripheral 1 according to the present embodiment, the reference chart 701 and the test print sheet 702 are arranged on the document table 209 when reading adjustment of the scanner 200 and print adjustment of the printer 100 are performed. The reference chart 701 and the test print sheet 702 are read simultaneously by operating the start key 241 once. Further, the multifunction device 1 separates the image data of the reference chart and the image data of the test print from the image data obtained by the reading, and uses the respective image data to read adjustment of the scanner 200 and print adjustment of the printer 100. And do. Therefore, the burden on the worker accompanying these adjustments can be reduced.

[Embodiment 2]
Another embodiment of the present invention will be described below with reference to the drawings.
The multifunction device 1 of the present embodiment performs print adjustment of the printer 100 by a method different from the method described above. The method will be described in detail below. Here, for example, the test print sheet 1002 shown in FIG. 14 is used as the test print sheet. It is also possible to use the test print sheet 702 in the same manner. The size of the test print sheet 1002 is A4.

  FIG. 11 is a schematic diagram showing an example of the exposure unit 10 shown in FIG. In the figure, laser light emitted from an LED head (light beam irradiating unit) 801 is shaken in the main scanning direction by a polygon mirror (light beam irradiating unit) 802 and irradiated onto the photosensitive drum 3. As a result, an electrostatic latent image is formed on the photosensitive drum 3, and the electrostatic latent image is developed with toner to become a toner image. In irradiating the photosensitive drum 3 with laser light, the laser light is applied to the photosensitive drum 3 through a lens 803 for magnification adjustment and with a beam detector (BD) 804 as a reference position.

  FIG. 12 is an explanatory diagram illustrating a process in which print adjustment of the printer 100 is performed. In the figure, a read image of the test print sheet 1002 by the scanner 200, a virtual image after the printing magnification correction, and a virtual image after the off-center adjustment are shown. The read image is a test print image 761 stored in the image data storage unit 601 obtained by reading the test print sheet 1002. However, in order to clarify the positional relationship, it is shown as an image on the photosensitive drum 3 in FIG.

  In the print adjustment of the printer 100, the print adjustment unit 441 of the main control unit 401 first performs (1) magnification correction calculation. In this process, the white part width actual value a1 is obtained from the read image, and the magnification correction value is obtained from the white part width actual value a1 and the white part width ideal value a2. Note that the white portion width corresponds to the interval of P13 (reference position on sheet) -P14 (reference position on sheet) in FIG. For example, when the white part width actual value a1 is 198 mm and the white part width ideal value a2 is 200 mm, the white part width actual value a1 is 1% (1-198 / 200) shorter than the white part width ideal value a2. It will be.

  Next, (2) BD distance virtual value calculation is performed. In this process, the virtual BD distance b1 is obtained from the result of the above (1) magnification correction calculation and the ideal BD distance b2. In this case, the reference position (the reference position on the sheet) is the lower end portion (corresponding to the position P13 in FIG. 14) of the upper frame portion of the test print image 761, and from this reference position to the virtual BD position existing in the main scanning direction. Find the distance. For example, assuming that the ideal BD distance b2 is 60 mm, the virtual BD distance b1 is 59.4 mm (60 mm × 0.99) considering that the actually measured value is 99% of the ideal value from the result of (1) above. It becomes.

  Next, (3) frame width calculation after magnification correction is performed. In this process, the upper frame actual measurement width c1 (P3-P13 interval) in the read image and the difference d1 between the ideal BD distance b2 and the virtual BD distance b1 are obtained, and the print magnification correction is performed from the obtained both values (c1, d1). An upper frame magnification correction width c2 (P3-P13 interval) in the rear virtual image is obtained. For example, if the upper frame portion actual measurement width c1 in the read image is 50 mm, the ideal BD distance b2 is 60 mm, and the virtual BD distance is 59.4 mm, the difference d1 is 0.6 mm. The partial magnification correction width c2 is 50.6 mm (50 mm + 0.6 mm).

  Finally, (4) off-center correction distance calculation is performed. In this process, a difference d2 between the upper frame portion reference width c3 and the upper frame portion magnification correction width c2 is obtained and set as an off-center correction distance. For example, if the upper frame portion reference width c3 is 48.5 mm and the upper frame portion magnification correction width c2 is 50.6 mm, the difference d2 is −2.1 mm (48.5 mm−50.6 mm). The off-center correction distance is -2.1 mm.

  Through the above processing, the print magnification correction value (+ 1%) and the off-center adjustment value (off-center correction distance: -2.1 mm) are obtained, and the print adjustment of the scanner 200 can be performed using these values.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  The configuration of the image forming apparatus of the present invention can be applied to a multifunction peripheral of a digital copying machine including a scanner and a printer.

FIG. 2 is a block diagram illustrating a functional configuration for reading adjustment of a scanner and print adjustment of a printer of an image forming apparatus according to an embodiment of the present invention. It is a block diagram which shows the structure of the main control part shown in FIG. 1 is a front view illustrating an internal configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 4 is a plan view showing an operation panel provided in the image forming apparatus shown in FIG. 3. FIG. 5A is an explanatory diagram showing a reference chart used for scanner read adjustment in the image forming apparatus shown in FIG. 3, and FIG. 5B is a test used for printer print adjustment in the image forming apparatus. It is explanatory drawing which shows a printing sheet. It is explanatory drawing which shows the relationship between the test print pattern memorize | stored in the test print pattern memory | storage part shown in FIG. 1, and the test print sheet on which this test print pattern was printed. 2 is a flowchart illustrating a method of reading adjustment of a scanner and printing adjustment of a printer having the configuration illustrated in FIG. 1. FIG. 4 is an explanatory diagram showing a state in which a reference chart and a test print sheet are placed on the document table shown in FIG. 3. It is a flowchart which shows the detail of the reading adjustment of the scanner in S7 shown in FIG. FIG. 8 is a flowchart showing details of print adjustment of the printer in S8 shown in FIG. 7. FIG. FIG. 4 is a schematic diagram showing an example of an exposure unit shown in FIG. 3. FIG. 9 is a diagram illustrating another embodiment of the present invention and illustrating a process in which print adjustment of a printer is performed with the configuration illustrated in FIG. 1. It is explanatory drawing which shows the conventional reference | standard chart used for the reading adjustment of a scanner. It is explanatory drawing which shows the conventional test print sheet used for the printing adjustment of a printer.

Explanation of symbols

1 MFP (image forming device)
3 Photosensitive drum 101 Document placement guide 111 Front guide part 112 Upper guide part 100 Printer (printing part)
200 Scanner (image reading unit)
209 Document table 401 Main control unit (image reading unit adjusting unit, printing unit adjusting unit)
411 First image segmentation unit (image segmentation means)
421 Image second cutout section 431 Reading adjustment section 441 Print adjustment section 501 γ adjustment section (gradation adjustment means)
603 Test print pattern storage unit 701 Reference chart 702 Test print sheet 711 Reading adjustment chart 712 γ adjustment chart (gradation adjustment chart)
721 Frame image 731 Direction mark 751 Test print pattern image 761 Test print image 801 LED head (light beam irradiation unit)
802 Polygon mirror (light beam irradiation part)
804 Beam detector 1001 Reference chart 1002 Test print sheet P13 Lower end position of upper frame portion of rectangular frame (reference position on sheet)
P14 Upper end position of the lower frame part of the rectangular frame (reference position on the sheet)

Claims (7)

An image forming apparatus including an image reading unit that reads an image of a document placed on a document table, and a printing unit that performs printing based on image data of the document obtained from the image reading unit.
An adjustment image obtained by continuously reading a reference chart arranged in the sub-scanning direction on the document table and a test print sheet obtained by the printing operation in the printing unit in this order. Image reading unit adjustment means for performing reading adjustment of the image reading unit based on the image data of the reference chart in the data;
An image forming apparatus comprising: a printing unit adjustment unit configured to perform printing adjustment of a printing unit based on image data of a test print sheet in the adjustment image data after the reading adjustment of the image reading unit.   The image data for adjustment is divided into image data of a reference chart and image data of a test print sheet, and an image separation unit is provided that supplies the former to the image reading unit adjustment unit and the latter to the printing unit adjustment unit. The image forming apparatus according to claim 1, wherein: Gradation adjustment means,
The reference chart includes a reading adjustment chart and a gradation adjustment chart,
The image reading unit adjustment means performs reading adjustment of the image reading unit based on the image data of the read adjustment chart included in the image data of the reference chart of the adjustment image data,
The image forming apparatus according to claim 1, wherein the gradation adjustment unit performs gradation adjustment based on image data of a gradation adjustment chart included in image data of a reference chart of adjustment image data. The test print sheet has an image showing a reference position on the sheet that is a predetermined distance from the edge of the sheet to the inside of the sheet at both ends of the sheet in the main scanning direction,
The printing unit develops the electrostatic latent image formed on the photosensitive member with a developer and transfers the developer image onto a sheet. The beam detector and the beam detector serve as a reference position on the photosensitive member. A light beam irradiating unit for irradiating the light beam,
The printing unit adjusting means calculates a correction value of the printing magnification from the measured distance between the reference positions on both sheets indicated by the image data of the test print sheet and the specified distance between the reference positions on both sheets, A virtual position of the beam detector with respect to the reference position on the sheet on the beam detector side indicated by the image data is obtained, and the virtual position, an ideal distance from the virtual position to the reference position on the sheet, and a printing position from the specified reference position on the sheet are determined. The image forming apparatus according to claim 1, wherein a correction value is calculated, the print magnification is adjusted based on the print magnification correction value, and the print position is adjusted based on the print position correction value. An image reading unit that reads an image of a document placed on a platen and a printing unit that performs printing based on the image data of the document obtained from the image reading unit. The printing unit is formed on a photoconductor. The developed electrostatic latent image is developed with a developer, the developer image is transferred onto a sheet, and a beam detector and a light beam for irradiating the photosensitive member with a light beam with the beam detector as a reference position In an image forming apparatus having an irradiation unit,
An image obtained by reading the test print sheet on which the image indicating the reference position on the sheet, which is a predetermined distance from the edge of the sheet to the inside of the sheet, is formed on both ends of the sheet in the main scanning direction, by the image reading unit. Using the data, the correction value of the printing magnification is calculated from the measured distance between the reference positions on both sheets indicated by the image data and the specified distance between the reference positions on both sheets, and the image data of the test print sheet indicates Calculates the virtual position of the beam detector relative to the reference position on the sheet on the beam detector side, and calculates the correction value of the printing position from the virtual position, the ideal distance from the virtual position to the reference position on the sheet, and the specified reference position on the sheet. Printing section adjustment means for adjusting the print magnification based on the print magnification correction value and adjusting the print position based on the print position correction value. An image forming apparatus comprising. In an adjustment method for an image forming apparatus, comprising: an image reading unit that reads an image of a document placed on a document table; and a printing unit that performs printing based on image data of the document obtained from the image reading unit.
A reading step in which the image reading unit sequentially reads the reference chart arranged in the sub-scanning direction on the document table and the test print sheet obtained by the printing operation in the printing unit in this order;
An image reading unit adjustment step for performing reading adjustment of the image reading unit based on the image data of the reference chart in the adjustment image data obtained in the reading step;
An image forming apparatus adjustment comprising: a printing unit adjustment step of performing printing adjustment of a printing unit based on image data of a test print sheet in the adjustment image data after the reading adjustment of the image reading unit Method. An image reading unit that reads an image of a document placed on a platen and a printing unit that performs printing based on the image data of the document obtained from the image reading unit. The printing unit is formed on a photoconductor. The developed electrostatic latent image is developed with a developer, the developer image is transferred onto a sheet, and a beam detector and a light beam for irradiating the photosensitive member with a light beam with the beam detector as a reference position In an adjustment method of an image forming apparatus having an irradiation unit,
A reading step of reading a test print sheet on which an image showing a reference position on the sheet, which is a predetermined distance from the edge of the sheet to the inside of the sheet, is formed at both ends of the sheet in the main scanning direction;
The correction value of the printing magnification is calculated from the measured distance between the reference positions on both sheets indicated by the image data obtained in the reading step and the specified distance between the reference positions on both sheets, and the image data of the test print sheet The virtual position of the beam detector with respect to the reference position on the sheet on the beam detector side indicated by is obtained, the ideal position from the virtual position to the reference position on the sheet from the virtual position, and the correction value of the printing position from the specified reference position on the sheet An image forming apparatus comprising: a printing unit adjustment step that calculates a print magnification based on a print magnification correction value and adjusts a print position based on a print position correction value. Method.

Images