JP2007060551A - Deviation measuring method, deviation correcting apparatus, and deviation correction program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deviation measuring method with which deviation of images output onto front and rear sides of paper can be accurately and easily measured, a deviation correcting apparatus and deviation correction program with which the deviation of images output onto front and rear sides of paper can be accurately corrected. <P>SOLUTION: A deviation measuring method for measuring deviation between both sides in double-sided printing includes: a chart output process of outputting, from an image output device, charts having reference curves with a known curvature and a scale for reading positions on these reference curves onto a first side and a second rear side between both sides of paper; a crossing position read process of reading, from the scale, the position of a crossing where a tangent with respect to a reference curve existent inside curving, between reference curves output onto the first side and the second side, crosses the other reference curve; and a curve distance calculation process of calculating a distance, vertical to the tangent, mutually between the reference curves output onto the first side and the second side based on the read position. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a deviation measuring method for measuring a deviation of images output on both sides of a sheet, a deviation correction apparatus for correcting a deviation of images scheduled to be output on both sides of a sheet, and a computer. The present invention relates to a shift correction program for operating as a correction device.

  Conventionally, in the field of printing, double-sided printing for outputting images on both sides of paper has been widely performed. Image output devices for double-sided printing include a double-sided simultaneous type that outputs images on both sides of the paper simultaneously, and a single-sided type that outputs an image on the back side of the paper after outputting the image on the front side of the paper, etc. It has been known. Also, when creating multiple printed materials such as booklets and business cards, the operator edits a layout in which multiple images are placed on a single large sheet, and images are output according to such a layout. The paper is cut according to the finished size.

  Here, when creating a business card etc. with double-sided printing, if the image is shifted between the front and back sides, when the paper is cut to fit on the image on one side, the edge is printed on the other side. There is a risk of problems such as missing. Normally, the layout is edited so that the positions of the front and back images match exactly, but the actual output position of the image is slightly shifted from the position on the layout due to defects in the image output device. It may end up. In order to prevent such problems, the image is actually output by arranging the image on the layout by deviating from the original writing position in consideration of characteristics such as wrinkles of the image output device. Offset adjustment that corrects the offset (deviation of the writing position) is known.

  In recent years, in the field of printing, an electrophotographic image output device that fixes a toner image on paper has been widely used. In an image output device that employs this electrophotographic method, an image is placed on the paper. When forming, the paper may be deformed due to heat or pressure applied to the paper. In particular, when double-sided output is performed with the single-sided image output device described above, the front side image is output, and then the back side image is output with the paper deformed. For this reason, even when images of the same size are output on the front and back surfaces of the paper, as a result, the sizes of the images output on the front and back surfaces are different from each other. There is a problem that it is not possible to prevent such image displacement.

As a method of matching the size of the image output on each of the front and back surfaces, the same size frame is output on the front and back surfaces of the paper, and the size deviation is calculated by measuring the dimensions of those frames. In addition, when actually outputting a desired image, a method of outputting an image whose size has been corrected based on the amount of dimensional deviation has been proposed (for example, see Patent Document 1).
JP 2004-54802 A

  However, in the method described in Patent Document 1, the measurement for calculating the dimensional deviation amount takes time, and the entire correction work becomes troublesome.

  SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides a deviation measuring method capable of accurately and easily measuring a deviation of an image output on the front and back surfaces of a sheet, and accurately correcting a deviation of an image output on the front and back sides of a sheet. It is an object of the present invention to provide a deviation correction apparatus and a deviation correction program that can be used.

The deviation measuring method of the present invention that achieves the above object is as follows.
An image that outputs a first image on the first side of both sides of the paper and outputs a second image on the second side of the back side of the first side, thereby outputting an image on both sides of the paper. In a displacement measuring method for measuring a displacement between the first image and the second image output by an output device,
A chart output process of outputting a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the reference curves output to the first surface and the second surface in the chart output process, the position of the intersection where the tangent to the reference curve existing on the inside of the curve intersects the other reference curve is determined by the scale. Reading intersection position reading process;
A curve distance calculating step of calculating a distance in a direction perpendicular to the tangent line between the reference curves output to the first surface and the second surface based on the position read in the intersection position reading step. It is characterized by that.

  Here, the “reference curve having a known curvature” output to the first surface and the “reference curve having a known curvature” output to the second surface are the same curve as long as the curvature is known. There may be a different curve.

  When using the single-sided image output device described above, the paper is deformed due to the effects of heat and pressure applied when the image is output on the first side of the paper, and the toner used to form the image. However, when the image is output on the second surface in a state where the paper is deformed, there is a possibility that the position of the image output on each of the both surfaces of the paper and the size of the image are relatively shifted.

  According to the misalignment measuring method of the present invention, it is not necessary to use a measuring instrument such as a ruler to measure such misalignment, so that it is easy to measure the misalignment of the images output on the front and back surfaces of the paper. it can. In addition, since the intersection point between the reference curve and the tangent line is read on the scale, a slight deviation is enlarged on the scale, and measurement can be performed with high accuracy.

  Further, in the deviation measuring method of the present invention, “the chart has the reference curve at a position corresponding to each of a plurality of locations on the paper, and the intersection position reading process includes the intersection points at each of the plurality of locations. The curve distance calculation process is a process of calculating the distance at each of the plurality of locations, and the first image and the first image are calculated based on the distance calculated in the curve deviation calculation process. The form of “having a dimensional deviation calculation process for calculating a dimensional deviation from the second image” is a preferable form.

  With such a configuration, it is possible to easily and accurately measure a relative shift in size when images are output on both sides of a sheet.

Further, in the deviation measuring method of the present invention, “the chart has the reference curve at a position corresponding to each of a plurality of locations on the paper,
The intersection position reading process is a process of reading the position of the intersection at each of the plurality of locations,
The curve distance calculation process is a process of calculating a distance at each of the plurality of locations,
It is also a preferable mode to have a misregistration calculation process of calculating a misregistration between the first image and the second image based on the distance calculated in the curve distance calculation process.

  With such a configuration, it is possible to easily and accurately measure a relative shift in position when images are output on both sides of a sheet.

  Further, in the deviation measuring method of the present invention, “the chart has a reference curve in which a portion parallel to the edge of the paper exists as the reference curve, and the intersection position reading process includes the edge of the paper. "The process of reading the position of the intersection point with respect to a tangent line parallel to" is also a preferred form.

  With such a configuration, it is possible to measure the deviation of the paper in the vertical direction and the horizontal direction.

  Further, in the deviation measuring method of the present invention, “the cutting process of cutting the paper at the position of the tangent line, and the intersection position reading process is the edge of the paper cut in the cutting process and the reference curve. The form “is the process of reading the position of the intersection of the above-mentioned on the scale” is also a preferable form.

  By cutting the paper at the position of the tangent, the tangent of the reference curve on one side of the paper can be easily recognized from the other side of the paper, and the deviation can be measured.

  Further, in the deviation measuring method of the present invention, “the chart has a plurality of arcs sharing a center as the reference curve, and has a radial angle scale extending from the center as the scale”. The form is a preferred form.

  If the “distance perpendicular to the tangent” is very small and difficult to read, read the position of the above intersection as an angle, and convert the read angle to obtain the distance in the direction perpendicular to the tangent. It is easier to measure the deviation than reading the distance in the direction perpendicular to the tangent.

Moreover, the deviation correction apparatus of the present invention that achieves the above-described object is
An image that outputs a first image on the first side of both sides of the paper and outputs a second image on the second side of the back side of the first side, thereby outputting an image on both sides of the paper. In a shift correction device that corrects a shift between the first image and the second image output by an output device,
A chart output unit for outputting a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the reference curves output to the first surface and the second surface, reading is performed by reading the position of the intersection where the tangent to the reference curve existing on the inside of the curve intersects the other reference curve by the scale. A value acquisition unit that acquires a value at any stage from a value to a deviation value that represents a deviation between the first image and the second image, which is finally derived based on the read value; ,
A shift correction unit that performs shift correction on the second image based on the value acquired by the value acquisition unit and causes the image output apparatus to output the second image that has been corrected. It is characterized by.

  According to the misalignment correction apparatus of the present invention, misalignment of images scheduled to be output on the front and back surfaces of a sheet can be accurately corrected. Further, by converting the positional deviation amount into the deviation correction amount, it is possible to save the operator from manually calculating the deviation correction amount.

  Further, in the misalignment correction apparatus of the present invention, “the chart has a plurality of arcs sharing a center as the reference curve, and has a radial angle scale extending from the center as the scale, A preferred embodiment is a form in which the reading value is a value obtained by reading the position of the intersection point where the tangent to the arc intersects the other arc by the angle scale, and the value acquisition unit acquires the reading value itself. It is.

  With such a configuration, the operator can easily correct the image shift on the front and back surfaces of the sheet only by reading and inputting the angle scale.

Further, the deviation correction program of the present invention is executed in a computer system, and the computer system
An image that outputs an image on both sides of the paper by outputting a first image on the first side of both sides of the paper and outputting a second image on the second side of the back side of the first side In a shift correction program for correcting a shift between the first image and the second image output by the output device,
On the computer system,
A chart output unit for outputting a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the reference curves output to the first surface and the second surface, reading is performed by reading the position of the intersection where the tangent to the reference curve existing on the inside of the curve intersects the other reference curve by the scale. A value acquisition unit that acquires a value at any stage until a deviation value representing a deviation between the first image and the second image, which is finally derived from the reading unit based on the read value; ,
A deviation correction unit configured to apply a deviation correction based on the value acquired by the value acquisition unit to the second image and to output the second image subjected to the deviation correction to the image output device; It is characterized by.

  Note that the misalignment correction apparatus and misalignment correction program according to the present invention are only shown in its basic form here, but this is merely to avoid duplication, and the misalignment correction apparatus and misalignment correction program according to the present invention. Includes not only the above basic form but also various forms corresponding to the above-described forms of the deviation measuring method.

  Further, in the deviation correction apparatus of the present invention and the deviation correction program, the same name such as a chart output unit is given as a component name constituting them, but in the case of a deviation correction program, In the case of a deviation correction device, the software includes hardware.

  ADVANTAGE OF THE INVENTION According to this invention, the shift | offset | difference measuring method which can measure the shift | offset | difference of the image output on the front and back of a sheet | seat accurately and easily, and the shift | offset | difference of the image output on the front and back | rear side of a sheet | seat can be correct | amended accurately. A deviation correction apparatus and a deviation correction program can be provided.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is an overall configuration diagram of an image output system to which an embodiment of the present invention is applied.

  Here, editing workstations 101, 102, and 103, an image processing apparatus 200, and a printer 300 are shown.

  In the editing workstations 101, 102, and 103, editing software is used, and an editing operation for determining a layout of objects (pictures, texts, and line drawings) constituting an image is performed. As a result, page data such as PS (Post Script: registered trademark) data or PDF (Portable Document Format) data is generated, and the generated page data is output to the image processing apparatus 200.

  The image processing apparatus 200 operates as an embodiment of the deviation correction apparatus of the present invention. In the image processing apparatus 200, image correction processing for correcting the size and color of the image represented by the page data is performed on the page data sent from the editing workstations 101, 102, and 103. Since the page data cannot be output by the printer 300 as it is, the image processing apparatus 200 converts the page data into raster data for image output suitable for the printer 300, and sends the raster data to the printer 300. It is done.

  The printer 300 outputs the image represented by the raster data sent from the image processing apparatus 200 to both sides or one side of the designated paper. Here, in this embodiment, the printer 300 is a printer that employs an electrophotographic method that forms an image using toner while applying heat or pressure to the paper, and further outputs an image on the surface of the paper. After that, it is a single-sided printer that outputs an image on the back side. Therefore, if an image is output to both sides of the paper without going through the image correction processing in the image processing apparatus 200, the paper may be warped by the toner used when the image is output on the front surface. The sheet is deformed by heat and pressure, and an image is output on the back surface in this state. Therefore, there is a problem that the size of the image on the front surface and the back surface and the writing position are shifted. In order to prevent such a problem, in the present embodiment, the image processing apparatus 200 performs a process of correcting the size and the writing position of the back image in accordance with the front image output on the front surface.

  Here, the feature of the image output system shown in FIG. 1 as an embodiment of the present invention is the processing content executed by the image processing apparatus 200. First, the internal structure of the image processing apparatus 200 will be described.

  FIG. 2 is a hardware configuration diagram of the image processing apparatus 200 shown in FIG.

  As shown in FIG. 2, the image processing apparatus 200 includes a CPU 211 that executes various programs, a main memory 212 that reads programs stored in the hard disk device 213 and develops them for execution by the CPU 211, An input interface for receiving page data connected to a hard disk device 213 storing various programs and data, an image display device 214 for displaying an image on a display screen, and editing workstations 101, 102 and 103 (see FIG. 1). 215, a keyboard 216 for inputting various information according to key operations, a mouse 217 for inputting an instruction corresponding to an icon or the like displayed at the position by designating an arbitrary position on the display screen, a flexible disk ( (Hereinafter referred to as FD) 400 is loaded and the loaded F FD drive 218 that accesses 400, CD-ROM 410 is loaded, CD-ROM drive 219 that accesses the loaded CD-ROM 410, and output interface 220 that sends raster data to printer 300 are built in. The elements are connected to each other via a bus 221.

  Here, an image correction for operating the image processing apparatus 200 shown in FIG. 1 as an embodiment of the shift correction apparatus of the present invention, to which the shift correction program of the present invention is applied, is applied to the CD-ROM 410. The program is stored. The CD-ROM 410 is loaded into the CD-ROM drive 219, and the image correction program stored in the CD-ROM 410 is uploaded to the image processing apparatus 200 and stored in the hard disk device 213. When the image correction program is activated and executed, the image processing apparatus 200 operates as an embodiment of the deviation correction apparatus of the present invention.

  Next, an image correction program executed in the image processing apparatus 200 will be described.

  FIG. 3 is a conceptual diagram showing a CD-ROM 410 in which an image correction program which is an embodiment of the deviation measurement program of the present invention is stored.

  The image correction program 500 includes a data input unit 510, a correction amount calculation unit 570, a measurement value acquisition unit 560, an image correction unit 540, and a rasterization unit 550. Details of each part of the image correction program 500 will be described together with actions of each part of the image processing apparatus 200 that operates as an embodiment of the deviation correction apparatus of the present invention.

  FIG. 4 is a functional block diagram of the image processing apparatus 200 when the image correction program 500 is installed in the image processing apparatus 200 shown in FIG. 1 and the image processing apparatus 200 is operated as an embodiment of the deviation correction apparatus of the present invention. It is.

  The image processing apparatus 200 illustrated in FIG. 4 includes a data input unit 610, a rasterization unit 640, an image correction unit 650, a correction amount calculation unit 680, and a measurement value acquisition unit 670. When the image correction program 500 shown in FIG. 4 is installed in the image processing apparatus 200 shown in FIG. 1, the data input unit 510 of the image correction program 500 constitutes the data input unit 610 of FIG. Reference numeral 570 constitutes a correction amount calculation unit 680, measurement value acquisition unit 560 constitutes a measurement value acquisition unit 670, image correction unit 540 constitutes an image correction unit 650, and rasterization unit 550 constitutes a rasterization unit 640. To do.

  The data input unit 610 receives page data such as PS data (registered trademark) generated by the editing workstations 101, 102, and 103 shown in FIG. The printer 300 shown in FIG. 1 is a single-sided single-sided double-sided printer, and when double-sided printing is performed, in addition to the table data representing the front image output on the front side of the paper, it is output on the back side of the paper. Back data representing the back image is also input. Hereinafter, a case where duplex printing is performed using the printer 300 will be described.

  Here, in the image processing apparatus 200 according to the present embodiment, before actually printing out a desired image, “trial” is performed in order to correct the deviation of the writing position and the dimensional deviation between the front surface image and the back surface image in double-sided printing. "Print" is executed. When the operator instructs execution of “trial print” using the mouse 217 or the keyboard 216 shown in FIG. 2, the “trial print” mode is set, and page data for “trial print” is sent from the data input unit 610 to the rasterized unit. 640. After being converted into raster data in a format suitable for the printer 300 by the rasterizing unit 640, the raster data is sent to the printer 300, and a double-sided image 700 of “trial print” is output from the printer 300 on both sides.

  The operator uses the output result of the “test print” double-sided image 700, and in the double-sided image 700, several types of parameters necessary for calculating the shift amount and dimensional shift amount of the writing position between the front image and the back image. And the measured value is input to a setting screen prepared in advance using the mouse 217 or the like. The measurement values of various parameters input by the operator are acquired by the measurement value acquisition unit 670, and the correction amount calculation unit 680 further calculates the front surface image and the back surface image according to a predetermined procedure to be described later based on the acquired measurement values. A correction amount for correcting the deviation of the writing position and the dimensional deviation is calculated.

  When the “trial print” is completed and the operator instructed the double-sided output of the image to be output this time, the “normal print” mode is set, and the page data representing the image is corrected from the data input unit 610. The image correction unit 650 corrects the writing position shift and the size shift between the front surface image and the back surface image in double-sided printing based on the result of the “trial print”, and then corrects the page. The data is converted into raster data by the rasterizing unit 640 and a “normal print” double-sided image 730 is output on both sides from the printer 300.

  The image processing apparatus 200 is basically configured as described above.

  FIG. 5 is a flowchart showing a series of work procedures performed by the image processing apparatus 200 when correcting the dimensional deviation of the image output on both sides of the paper and the positional deviation of the writing.

  In the following, this flowchart is used to apply one embodiment of the deviation measurement method of the present invention to measure and correct the deviation of the image that is scheduled to be output on both sides of the paper, and then the image on both sides of the paper. A series of processing until output is described.

  First, according to the parameter setting screen provided by the image correction program 500 shown in FIG. 3, various parameters for outputting the “test print” double-sided image 700 are set by the operator (step S1 in FIG. 5).

  FIG. 6 is a diagram showing a parameter setting screen displayed on the display screen of the image processing apparatus 200 shown in FIG.

  A setting screen 800 shown in part (A) of FIG. 6 includes a copy number setting unit 810 for setting the number of output images and a print pattern setting unit 820 for setting an output format such as single-sided / double-sided printing. , A page direction setting unit 830 for setting the orientation of each of the front and back pages, and a print range setting for setting a page range to be printed when a series of image data composed of a plurality of pages is sent. A section 840, a sheet setting section 850 for setting the sheet size, a printing color plate setting section 860 for setting the color of toner used for image formation, and a printing mode setting section 870, which will be described later. Further, an OK button 881 for confirming the setting contents and a cancel button 882 for canceling the setting contents are provided. The print mode setting unit 870 further includes a print target setting unit 871 for designating an object to be output on paper among image and line drawing objects included in page data (PS data and PDF data), and back surface dimension / position correction. Button 872 is provided.

When the operator selects the back dimension / position correction button 872 with the mouse 217 or the like, a pop-up screen 873 as shown in part (B) of FIG. 6 is displayed. In the pop-up screen 873, when printing is performed on the back surface, a measurement value necessary for calculating a correction amount for dimensional deviation or positional deviation with respect to the front surface is input. As will be described later, this measured value is represented by an angle and a circle designation.

  When outputting the “trial print” double-sided image 700, the “copy number setting unit 810” shown in Part (A) of FIG. 6 sets the number of copies to one, and the “print pattern setting unit 820”. The fifth selection number for performing double-sided printing is set, and the “front and back page direction setting unit 830”, “print range setting unit 840”, “paper selection setting unit 850”, “print color plate setting” are set. Section 860 ”and“ print mode setting section 870 ”are set to the initial state (default) state shown in the drawing. In the initial state (default), the pop-up screen 873 that appears when the back surface dimension / position correction button 872 of the “print mode setting unit 870” is selected, as shown in part (B) of FIG. “Upstream Measurement Value Input Unit 874a in Scanning Direction”, “Downstream Measurement Value Input Unit 874b in Main Scanning Direction”, “Upstream Measurement Value Input Unit 874a in Sub Scanning Direction”, “Downstream Measurement Value Input in Sub Scanning Direction” “0.00” is input as the value of “angle” in any measurement value input part of “part 874b”, and there is no check (designation) in any of the four fields designated by the circle. It has become. Such a state where the “angle” is “0.00” and no check (designation) is entered in any of the four columns designated by the circle means that the size of the back image is shifted from the front image. This corresponds to outputting as it is without correcting the positional deviation of the writing.

  When outputting the “trial print” double-sided image 700, the selection is performed as described above, and the OK button 881 shown in Part (A) of FIG. 6 is pressed to confirm these selections.

At this time, in the image processing apparatus 200 shown in FIG. 4, the value input on the pop-up screen 873 is acquired by the measurement value acquisition unit 660. -
Subsequently, using a “trial print instruction button” (not shown) prepared in advance, an instruction to output the “trial print” duplex image 700 shown in FIG. A double-sided image 700 is output on both sides (step S2 in FIG. 5).
The process of step S2 corresponds to an example of a chart output process in the deviation measuring method of the present invention. The image output by the “trial print” is a chart in which a radial scale represented by four concentric circles having different radii around a predetermined reference position and an angle scale centered on the reference position are drawn. Yes, this chart is output on each of the front and back sides of the paper.

  FIG. 7 is a diagram illustrating the surface of the double-sided image 700 of “trial print”.

  As shown in the figure, on the surface 710, four concentric circles 11, 12, 13, and 14 having different radii centered on the origin O and angle scales in increments of 0.5 ° centered on the origin O are drawn. A chart is output. The printer 300 cannot output an image over the entire surface 710 because of its function, and what is actually printed on the surface 710 is a print surrounded by the four-dot chain lines S1 to S4 in the figure. Limited to possible areas. In the figure, in order to clearly show four concentric circles 11, 12, 13, and 14, each circle outside the printable area is also represented by a dotted line. Here, the data of the ratio of the radii of the four concentric circles 11, 12, 13, and 14 having different radii are stored in advance in the correction amount calculation unit 680 shown in FIG. The radial scales represented by the four concentric circles and the angular scales in increments of 0.5 ° constitute a two-dimensional polar coordinate system for representing the position on the paper. Further, the direction from right to left toward the front surface 710 of the sheet is the sub-scanning direction (direction in which the sheet is sent to the printer 300), and the direction from top to bottom is the main scanning direction.

Of the four concentric circles, the first concentric circle 11 is substantially in contact with the two alternate long and short dash lines S1 and S2 extending in the sub-scanning direction, which are the boundaries of the printable area, at the contacts P ₁ and P ₂ , respectively. In addition, the third concentric circle 13 is substantially in contact with two alternate long and short dash lines S3 and S4 extending in the main scanning direction, which are boundaries of the printable area, respectively, at the contact points P ₃ and P ₄ , respectively. The operator prints the “test print” double-sided image 700 along the tangent lines (almost two dash-dot lines S1 and S2) at the contacts P ₁ and P ₂ extending in the sub-scanning direction. The double-sided image 700 is cut, and the “test print” double-sided image 700 after cutting is then tangent to the contact points P ₃ and P ₄ extending in the main scanning direction (almost two one-dot chain lines S3). , S4). The first concentric circles 11 so that both the back and front sides of the cut paper are within the printable area even if there is a shift in the position of the printable area between the back and front when output. Is printed slightly inside the area sandwiched between the two dashed-dotted lines S1 and S2, and the third concentric circle 13 is printed slightly inside the area sandwiched between the two dashed-dotted lines S3 and S4. Has been.

As a result of the above cutting, when the radius of the first concentric circle 11 and the radius of the third concentric circle 11 are the radii R ₁ and R ₃ , respectively, the width in the sub-scanning direction is the diameter “2 × R of the first concentric circle 11. ₃ ”and the rectangular portion having the diameter“ 2 × R ₁ ”of the third concentric circle 11 in the main scanning direction is cut out from the double-sided image 700 of“ trial print ”.

  FIG. 8 is a view of the rectangular portion cut out from the “trial print” double-sided image 700 in FIG. 7 as seen from the back side.

  The same chart as FIG. 7 is also printed on the back side of the double-sided image 700 of “trial print”. Originally, the origin O of the chart of the front surface 710 shown in FIG. 7 and the origin O ′ of the chart of the back surface 720 of FIG. 8 exactly match each other, and each of the four concentric circles 11, 12, 13, 14 of the front surface 710 The radius and the radius of each of the four concentric circles 21, 22, 23, 24 on the back surface 720 should be exactly the same. However, due to the heat and pressure applied when printing the front surface 710, the influence of paper warpage due to the toner used when printing is performed on the front surface 710, or the wrinkles of the printer 300, the back surface 720 When the print output is performed, the position of the origin O ′ of the chart on the back surface 720 and the radius of the concentric circle may be shifted from the position of the origin O of the chart of the front surface 710 and the radius of the concentric circle. For this reason, as shown in FIG. 8, the first concentric circle 21 on the back surface moves upward (upstream in the main scanning direction) in the figure and protrudes from the upper side of the rectangle, or the third concentric circle 23 on the back surface is illustrated. May move to the left side (downstream in the sub-scanning direction) and protrude from the left side of the rectangle. Further, as shown in the figure, the dimensional shift (that is, the magnification with respect to the surface 710) is different between the main scanning direction and the sub-scanning direction, and may be slightly shifted from the circle to become an ellipse. Accordingly, it is possible to calculate a positional deviation or a dimensional deviation between the chart on the front surface 710 and the chart on the rear surface 720, and reflect the result on the correction amount of the deviation when outputting the actual image desired by the operator. I need it. Hereinafter, measurement that provides data necessary for calculating the deviation will be described. This measurement is performed on the back chart.

  As shown in FIG. 8, the first concentric circle 21 on the back surface intersects the upper side of the rectangle (upstream side in the main scanning direction), and similarly, the second concentric circle 22 on the back surface 720 has the lower side of the rectangle (main The third concentric circle 23 on the back surface 720 intersects the left side of the rectangle (downstream in the sub-scanning direction), and the fourth concentric circle 24 on the back surface 720 intersects the right side of the rectangle (secondary side in the scanning direction). It intersects with the edge on the upstream side in the scanning direction. When each of these concentric circles intersects each side, a part of the arc of each concentric circle is cut off. Hereinafter, the first concentric circle 21 on the back surface 720 that intersects the upper side of the rectangle (upstream in the main scanning direction) will be described as an example.

  FIG. 9 is a view showing the vicinity of the intersection where the side on the upstream side in the main scanning direction and the first concentric circle on the back surface 720 intersect among the four sides of the rectangular portion cut out from the double-sided image 700 of “trial print”. It is.

As shown in the figure, the first concentric circle 21 on the back surface 720 intersects the first scanning point A ₁ and the second intersecting point A ₂ with the upstream side in the main scanning direction among the four sides of the rectangular portion of FIG. ing. In FIG. 7, the concentric circle 11 that is in contact with the side on the upstream side in the main scanning direction of the rectangular portion at the contact P <b> 1 moves upward in the drawing, and as a result, the back surface 720 corresponding to the contact P ₁ on the front surface 710. The upper point indicates that it has moved out of the rectangular portion and moved to a point P ₁ ′ on the back surface 720 shown in FIG. Here, using the angle scale on the chart, the operator uses the vertical line O′A ₃ drawn down from the origin O ′ on the back surface 720 to the line segment A ₁ A ₂ , the origin O ′ on the back surface 720, and the first The angle formed by the line segment O′A ₁ connecting the intersection A ₁ is measured. Since the angle scale on the chart is in increments of 0.5 °, it can be seen in FIG. 9 that this angle is “2.5 °” as shown in the figure. This angle is half of the angle (so-called defect angle) at which the arc A ₁ A ₂ of the first concentric circle 21 on the back surface 720 is seen from the origin O ′. The operator performs the same measurement of the missing angle (half) as described above for the other three sides of the rectangular portion shown in FIG. 7, and concentric circular arcs B ₁ B ₂ , C ₁ cut at each side. C ₂ and D ₁ D ₂ are performed, and the half value of the measured missing angle is input on the pop-up screen 873 shown in Part (B) of FIG. 6 together with the check of the corresponding concentric circles (FIG. 5). Step S3). The process of step S3 corresponds to an example of the intersection position reading process of the deviation measuring method of the present invention. With this input, the measurement value acquisition unit 670 shown in FIG. 4 acquires data necessary for calculating a correction amount for dimensional deviation and positional deviation during double-sided printing. Next, the calculation of the correction amount for the dimensional deviation and the positional deviation, which is performed using the acquired missing angle (half) data, will be described. This calculation is performed by a correction amount calculation unit 680 shown in FIG.

  First, the dimensional deviation will be described.

From the defect angle (half) data obtained in FIG. 9 (2.5 ° in FIG. 9), the perpendicular line O′A ₃ drawn down from the origin O ′ on the back surface 720 onto the line segment A ₁ A ₂ is obtained. The length is determined by using the radius R ₁ ′ of the first concentric circle 21 on the back surface 720,
Line segment O′A ₃ = R ₁ ′ × cos (missing angle of the first concentric circle 21 on the back surface 720/2)
Can be obtained as In FIG. 9, the “missing angle / 2 of the first concentric circle 21 on the back surface 720” in the above equation is 2.5 °.

The same measurement as described above is performed on the second concentric circle 22 of the back surface 720 and the lower side of the rectangle (downstream in the main scanning direction) in FIG. Accordingly, the length of the perpendicular line O′B ₃ lowered on the line segment B ₁ B ₂ connecting the _two intersections B ₁ and B ₂ is determined by using the radius R ₂ ′ of the first concentric circle 21 on the back surface 720. O′B ₃ = R ₂ ′ × cos (missing angle of the second concentric circle 22 on the back surface 720/2)
It is expressed.

A line segment A ₃ B ₃ , which is the sum of the line segment O′A ₃ and the line segment O′B ₃ , is the length in the main scanning direction of the rectangular portion of FIG. 8, and this length is the surface of FIG. It is the same as the diameter “2 × R ₁ ” of the first concentric circle 11 of 710. Therefore,
2 × R ₁ = R ₁ ′ × cos (missing angle of the first concentric circle 21 on the back surface 720/2)
+ R ₂ '× cos (missing angle of the second concentric circle 22 on the back surface 720/2) (1)
The following formula is established. Here, the ratio of the radius R ₁ ′ of the first concentric circle 21 on the back surface 720 to the radius R ₂ ′ of the second concentric circle 22 on the back surface 720 is equal to the radius R ₁ of the first concentric circle 11 on the front surface 710 and the back surface 720. It can be approximated to be the same as the ratio K ₁₂ to the radius R ₂ of the second concentric circle 12. The ratio K ₁₂ with a radius R ₂ of the second concentric 12 of radius R ₁ and the rear surface 720 of the first concentric circle 11 of the surface 710, since it is previously grasped, with the ratio K _12, the above equation From (1)
2 × R ₁ = R ₁ ′ × cos (missing angle of the first concentric circle 21 on the back surface 720/2)
+ R ₁ '× K ₁₂ × cos (missing angle of the second concentric circle 22 on the back surface 720/2)
Further, from this equation, the magnification ratio in the main scanning direction between the front surface 710 and the back surface 720, that is, the dimensional ratio T _m is T _m = R ₁ ′ / R ₁ = 2 / {cos (back surface 720 Deficit angle of the first concentric circle 21 of the / 2)
+ K ₁₂ × cos (missing angle of second concentric circle 22 on back surface 720/2)} (2)
As determined. Such a process of calculating the dimensional ratio T _m corresponds to an example of a dimensional deviation calculation process in the deviation measuring method of the present invention. From this dimensional ratio T _m , the dimensional deviation correction amount in the main scanning direction to be corrected when output to the back surface 720 in order to match the size (magnification) to the front surface 710 is the reciprocal of the dimensional ratio T _{m in} the main scanning direction. the be calculated as 1 / T _m.

A similar dimensional ratio calculation is performed by calculating the value of half of the defect angle measured with respect to the arcs D ₁ D ₂ and C ₁ C _{2 of the two} concentric circles 23 and 24 on the back surface 720 of FIG. using the ratio K ₃₄ with a radius R ₄ of the fourth concentric 14 of radius R ₃ of 3 concentric 13 and the rear surface 720 in turn performs the sub-scanning direction in FIG. 8. As a result, the radius R ₃ of the third concentric 13 surface 710, a third sub-scanning direction given by the ratio of the radius R ₃ 'of the concentric 23 size ratio T _s of the back surface 720,
T _s = R ₃ ′ / R ₃ = 2 / {cos (missing angle of the third concentric circle 23 on the back surface 720/2)
+ K ₃₄ × cos (missing angle of the fourth concentric circle 24 on the back surface 720/2)} (3)
As determined. From this dimensional ratio T _s , the dimensional deviation correction amount in the sub-scanning direction to be corrected when outputting to the back surface 720 in order to match the size (magnification) to the front surface 710 is the reciprocal of the dimensional ratio T _{s in} the sub-scanning direction. It is calculated as 1 / T _s .

When the dimensional ratio T _{m in the} main scanning direction and the dimensional ratio T _{s in the} sub-scanning direction are different, it means that the concentric circle on the back surface 720 is not completely a circle (perfect circle) but an ellipse. Therefore, the calculation based on the above-described angle measurement of the defect angle and the assumption that the four “concentric circles” on the back surface 720 in FIG. 8 are perfect circles (perfect circles) are not strictly correct but complete. Since the deviation from the circle (perfect circle) is extremely small, the dimensional ratio is calculated from the defect angle based on the assumption that the four “concentric circles” on the back surface 720 in FIG. 8 are perfect circles (true circles). By doing so, an approximate value with sufficient accuracy can be obtained.

  Next, the positional shift will be described. In the printer 300, when the dimensional deviation and the positional deviation are corrected and output, the upper right vertex (intersection of the alternate long and short dash lines S1 and S3) of the rectangle representing the printable area shown in FIG. The origin of Therefore, the deviation in the main scanning direction is corrected according to the distance from the reference line using the upstream side of the rectangle in the main scanning direction as a reference line. On the other hand, correction according to the distance from the reference line is performed with the side upstream in the sub-scanning direction as the reference line.

  Hereinafter, a description will be given by taking as an example a positional shift in the main scanning direction.

Of the four sides of the rectangular portion cut out from the double-sided image 700 of “trial print” shown in FIG. 7, the back surface 720 is located on the front surface 710 at a distance x from the upstream side in the main scanning direction. Is output at a distance x ′ from the upstream side in the main scanning direction on the back surface 720. Due to the effect of dimensional deviation and displacement (translation) between the front surface 710 and the back surface 720, between the two points x ′ and x,
x ′ = T _m × x + x ₀ (5)
The relationship is established. Here, T _m in the above equation (5) is a dimensional ratio calculated by the above-described dimensional displacement, and x _{0 in the} above equation (5) is a displacement amount representing the effect of displacement (parallel movement). is there. By obtaining the x _0, you can grasp the positional deviation (parallel movement). Such a process of calculating the positional deviation corresponds to an example of a positional deviation calculating process in the deviation measuring method of the present invention. This misregistration amount x ₀ corresponds to the amount of change at a point located on the upstream side of the main scanning direction that is the reference line on the surface 710 (that is, x = 0 in equation (5)). the contact P ₁ of the surface 710 shown in FIG. 7, is determined as the difference between the contact point P ₁ 'of the back surface 720 shown in FIG. Therefore, the positional deviation amount x ₀ is given by the line segment O′A ₃ -line segment O′P ₁ ′ in FIG. This amount is obtained by using the data of the missing angle (half of the above-described arc A ₁ A ₂ of the concentric circle 21 in FIG. 8 from the origin O ′.
x ₀ = T _m × R ₁ × {cos (missing angle of the first concentric circle 21 on the back surface 720/2) −1}
... (6)
It is expressed. Here, in FIG. 9, the “missing angle / 2 of the first concentric circle 21 on the back surface 720” in the above equation (6) is 2.5 °.
-X ₀ obtained by inverting the sign of the positional deviation amount x ₀ becomes the positional deviation correction amount for canceling the effects of positional deviation (called offset).

  With the calculation method described above, the correction amount calculation unit 680 in FIG. 4 calculates the dimensional deviation correction amount and the positional deviation correction amount (step S4 in FIG. 5), and performs “normal printing” performed after “trial printing”. The dimensional deviation correction amount and the positional deviation correction amount are set for print output by (step S5 in FIG. 5).

  A series of processing performed based on the operations from step S1 to step S5 in FIG. 5 described above is processing for setting the dimensional deviation correction amount and the positional deviation correction amount of the image.

  When printing the “normal print” double-sided image 730 that the operator actually wants to output as shown in FIG. 4, the print is output in an output method in which the set dimensional deviation correction amount and positional deviation correction amount are reflected. (Step S6 in FIG. 5).

  In this way, for example, double-sided edges are corrected by correcting the positional deviation and dimensional deviation of the image on the back surface with reference to the image on the front surface that is difficult to deviate from the position and dimension set for the first output. When creating a business card for printing, you can create a business card in which the size and the writing position of the front and back images are exactly the same, and when the paper is cut to fit the front image, the edge of the back image It is possible to suppress problems such as missing. In addition, in this method, since the operator can read the angle scale on the chart and input the value to the image processing apparatus 200 to correct the positional deviation and dimensional deviation, the operator uses a measuring instrument such as a ruler. There is no need to measure the correction, and the work for correction becomes simple.

  In the above description, the combination of the data input unit 610 and the rasterizing unit 550 corresponds to an example of the chart output unit of the deviation correction apparatus of the present invention, and the measured value acquisition unit 670 is the value acquisition unit of the deviation correction apparatus of the present invention. The image correction unit 650 corresponds to an example of a value acquisition unit of the deviation correction apparatus of the present invention.

  The above is the description of the present embodiment.

In this embodiment, when the “test print” double-sided image 700 is output, the “copy number setting unit 810” shown in part (A) of FIG. 6 outputs the copy number set to one. Although the positional deviation and the dimensional deviation were corrected using one “test print” double-sided image 700, in the present invention, the number of copies was set to 2 or more, for example, 10 and output. By calculating the misregistration correction amount and the dimensional misalignment correction amount for each of the ten “test print” double-sided images 700, and correcting the misalignment correction amount and the dimensional misalignment correction amount for the ten sheets, the correction is performed. It may be provided with a device for increasing the accuracy of the quantity.

  In the present embodiment, the operator inputs a measurement value of the concentric defect angle (half) on the back surface 720 to the image processing apparatus 200, and the image processing apparatus 200 calculates the positional deviation correction amount and The dimensional deviation correction amount is calculated, and when the desired double-sided image is output, these correction amounts are used as set values. However, according to the present invention, the operator can calculate the positional deviation correction amount and the dimensional deviation correction from the measured values. The amount may be calculated and input to the image processing apparatus, and the image processing apparatus may use the correction amount as a set value when outputting a desired double-sided image.

1 is an overall configuration diagram of an image output system to which an embodiment of the present invention is applied. It is a hardware block diagram of the image processing apparatus 200 shown in FIG. It is a conceptual diagram which shows CD-ROM410 in which the image correction program which is one Embodiment of the shift | offset | difference measurement program of this invention was memorize | stored. 2 is a functional block diagram of an image processing apparatus 200. FIG. 6 is a flowchart illustrating a series of work procedures performed by the image processing apparatus 200 when correcting a dimensional deviation and an output positional deviation of images output on both sides of a sheet. It is a figure which shows the parameter setting screen displayed on the display screen of the image processing apparatus 200 shown in FIG. FIG. 6 is a diagram illustrating a double-sided image 700 of “trial print”. FIG. 8 is a view of a rectangular portion cut out from a double-sided image 700 of “trial print” in FIG. 7 as viewed from the back side. FIG. 10 is a diagram illustrating the vicinity of an intersection where an upstream side in the main scanning direction and a first concentric circle on the back surface 720 intersect among four sides of a rectangular portion cut out from a double-sided image 700 of “trial print”.

Explanation of symbols

101, 102, 103 Editing workstation 200 Image processing apparatus 211 CPU
212 Main memory 213 Hard disk device 214 Image display device 215 Input interface 216 Keyboard 217 Mouse 218 FD drive 219 CD-ROM drive 220 Output interface 221 Bus 300 Printer 400 Flexible disk 410 CD-ROM
500 Image correction program 510 Data input unit 540 Image correction unit 550 Rasterization unit 560 Measurement value acquisition unit 570 Correction amount calculation unit 610 Data input unit 640 Rasterization unit 650 Image correction unit 670 Measurement value acquisition unit 680 Correction amount calculation unit 700 “Trial print” "Double-sided image" 710 Front side 720 Back side 730 "Normal printing" double-sided image 800 Setting screen 810 Copy number setting part 820 Print pattern setting part 830 Page orientation setting part 840 Printing range setting part 850 Printing color plate setting part 860 Paper setting part 870 Print mode setting section 871 Print target setting section 872 Back dimension / position correction button 873 Pop-up screen 874a Upstream measurement value input section 874a in the main scanning direction 875b Downstream measurement value input section in the main scanning direction 875a Upstream measurement value in the subscanning direction Force part 875b Downstream measurement value input part in the sub-scanning direction 881 OK button 882 Cancel button 11 First concentric circle on the surface 12 Second concentric circle on the surface 13 Third concentric circle on the surface 14 Fourth concentric circle on the surface 21 First concentric circle 22 Second concentric circle on the back surface 23 Third concentric circle on the back surface 24 Fourth concentric circle on the back surface

Claims (9)

An image that outputs a first image on the first side of both sides of the paper and outputs a second image on the second side of the back side of the first side, thereby outputting an image on both sides of the paper. In a displacement measuring method for measuring a displacement between the first image and the second image output by an output device,
A chart output process for outputting a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the respective reference curves output to the first surface and the second surface in the chart output process, the position of the intersection where the tangent to the reference curve existing inside the curve intersects the other reference curve is determined by the scale. Reading intersection position reading process;
A curve distance calculating step of calculating a distance in a direction perpendicular to the tangent line between the reference curves output to the first surface and the second surface based on the position read in the intersection position reading step. A deviation measuring method characterized by the above. The chart has the reference curve at a position corresponding to each of a plurality of locations on the paper;
The intersection position reading process is a process of reading the position of the intersection at each of the plurality of locations,
The curve distance calculation process is a process of calculating a distance at each of the plurality of locations,
The deviation measurement according to claim 1, further comprising a dimension deviation calculation process for calculating a dimension deviation between the first image and the second image based on the distance calculated in the curve deviation calculation process. Method. The chart has the reference curve at a position corresponding to each of a plurality of locations on the paper;
The intersection position reading process is a process of reading the position of the intersection at each of the plurality of locations,
The curve distance calculation process is a process of calculating a distance at each of the plurality of locations,
The displacement measurement process according to claim 1, further comprising: a displacement calculation process for calculating a displacement between the first image and the second image based on the distance calculated in the curve distance calculation process. Method. The chart has a reference curve having a portion parallel to the edge of the paper as the reference curve,
2. The deviation measuring method according to claim 1, wherein the intersection position reading step is a step of reading the position of the intersection point with respect to a tangent line parallel to the edge of the sheet. A cutting process of cutting the paper at the position of the tangent line;
2. The deviation measuring method according to claim 1, wherein the intersection position reading process is a process of reading the position of the intersection between the edge of the sheet cut in the cutting process and the reference curve by the scale.   The deviation measurement method according to claim 1, wherein the chart has a plurality of arcs sharing a center as the reference curve, and has a radial angle scale extending from the center as the scale. . An image that outputs a first image on the first side of both sides of the paper and outputs a second image on the second side of the back side of the first side, thereby outputting an image on both sides of the paper. In a shift correction device that corrects a shift between the first image and the second image output by an output device,
A chart output unit that outputs a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the reference curves output to the first surface and the second surface, reading is performed by reading the position of the intersection where the tangent to the reference curve existing on the inner side of the curve intersects the other reference curve by the scale. A value acquisition unit that acquires a value at any stage from a value to a shift value that is finally derived based on the read value and represents a shift between the first image and the second image; ,
A shift correction unit that performs shift correction on the second image based on the value acquired by the value acquisition unit and outputs the second image on which the shift correction has been performed to the image output device. A deviation correction device characterized by the above. The chart has a plurality of arcs sharing a center as the reference curve, and has a radial angle scale extending from the center as the scale,
The read value is a value obtained by reading the position of an intersection where a tangent to the arc intersects the other arc by the angle scale,
The deviation correction apparatus according to claim 7, wherein the value acquisition unit acquires the read value itself. Executed in a computer system,
An image that outputs a first image on the first side of both sides of the paper and outputs a second image on the second side of the back side of the first side, thereby outputting an image on both sides of the paper. In a shift correction program for correcting a shift between the first image and the second image output by an output device,
On the computer system,
A chart output unit that outputs a chart having a reference curve having a known curvature and a scale for reading a position on the reference curve on each of the first surface and the second surface by the image output device. When,
Of the reference curves output to the first surface and the second surface, reading is performed by reading the position of the intersection where the tangent to the reference curve existing on the inner side of the curve intersects the other reference curve by the scale. A value acquisition unit that acquires a value at any stage until a deviation value representing a deviation between the first image and the second image, which is finally derived from the reading unit based on the read value; ,
Forming a shift correction unit that applies a shift correction based on the value acquired by the value acquisition unit to the second image and outputs the second image subjected to the shift correction to the image output device; A misalignment correction program.

Images