JP2012247264A - Printed matter inspection method and printed matter inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for inspecting the printing state of a printed matter capable of recognizing the overall area of the printed matter in a pickup image from a first imaging part, and recognizing only the section of specific ink to be used for the printed matter in a pickup image from a second imaging part.SOLUTION: This printed matter inspection method includes: imaging a first image including an inspection reference mark and a printed matter by emitting first inspection rays of light; imaging a second image including the inspection reference mark and the printed matter by emitting second inspection rays of light having wavelength different from that of the first inspection rays of light; identifying the position of predetermined print content on the first image, and identifying the range of the printed matter on the basis of the position of the print content to inspect the print content included in the first image on the basis of the range of the printed matter; and identifying the range of the printed matter on the second image on the basis of a relative positional relation between the range of the printed matter identified in the first image and the inspection reference mark to inspect the print content included in the second image on the basis of the range of the printed matter.

Description

  The present invention relates to a printed matter inspection method and a printed matter inspection apparatus for inspecting the printed state of a printed matter, and in particular, based on the surface optical characteristics, the printed state of a large-sized printed matter that is printed by regularly arranging a plurality of printed original images with a blank portion interposed therebetween. The present invention relates to a printed matter inspection method and a printed matter inspection apparatus.

  As a method of printing a large amount of printed material, it was obtained by printing large originals that regularly arranged the same printing objects on large paper, instead of printing one printing object as an original image one by one A method is known in which each printed object is cut from a large-sized printed material to create a printed material (hereinafter referred to as “small piece”). In such a large-sized printed matter, each small piece is inspected on the large-sized printed matter before cutting each small piece. Specifically, it is inspected whether the printed content is appropriate or not by examining the optical characteristics of each small-sliced surface on a large-format printed material. This inspection is performed by comparing measurement data obtained by optically measuring a small cut area on a large-sized printed material to be inspected and reference data generated from a normally printed small cut.

  In order to accurately compare the reference data and the measurement data, it is necessary to accurately specify the position of the small cut on the large-sized printed material and measure the optical characteristics of the region corresponding to the reference data. As a technique for this purpose, for example, Patent Document 1 discloses a method for specifying a region having the highest correlation with reference data from image data obtained by imaging a region including a small slice.

JP 2002-63566 A

  In the printed matter, in addition to print contents such as characters printed with normal ink recognizable under visible light, print with special ink that cannot be recognized under visible light but can be recognized under a light source of a predetermined wavelength. Some have print contents such as a security mark.

  For example, FIG. 15A shows an infrared light image of a large-sized print printed with a plurality of small pieces arranged at regular intervals, and FIG. 15B irradiates the same large-sized print with ultraviolet light. The fluorescence image at the time is shown. The infrared light image is an image obtained by capturing infrared light reflected by irradiating the printed material with infrared light, and is an image close to a state visually recognized under natural light. A fluorescent image is an image of a state in which fluorescent ink is emitted by irradiating ultraviolet light, and such an image cannot be seen under natural light.

  As shown in FIG. 15A, number 102, characters, and patterns appear in the infrared light image, but the security mark 103 and the two-dimensional barcode on the fluorescent image shown in FIG. 15B do not appear. As shown in FIG. 15B, the security mark 103 or the like appears on the fluorescent image, but the number 102 or the like on the infrared light image shown in FIG. 15A does not appear. As described above, when the print contents captured by the two inspection lights are different, it is not possible to inspect the print contents such as the security mark 103 that appears only at the time of irradiation with ultraviolet light even if an infrared light image is used. However, even if a fluorescent image is used, it is not possible to inspect the printed content such as the number 102 that appears only in the infrared image. Depending on the ambient light at the time of image capture, characters and patterns captured in the infrared light image may appear blurry on the fluorescent image, but the image was captured more clearly for use in printed matter inspection. An image is desirable.

  For this reason, in the example of the large-sized printed matter shown in FIG. 15, two types of images are used: an infrared light image picked up using infrared light and a fluorescent image picked up by fluorescence irradiated with ultraviolet light. However, it is necessary to inspect the print contents included in each image. According to the above prior art, it is possible to specify the print contents included in each image by separately using the infrared light image and the fluorescent image and inspect the print state.

  However, since there is no print content included in both the infrared light image and the fluorescent image, the print content included in the infrared light image and the print content included in the fluorescent image are printed in the correct positional relationship. You may not be able to check that

  Specifically, for example, the image shown in FIG. 15A and the image shown in FIG. 15B are captured by different imaging devices. Since there is a possibility that each imaging device has captured a different area, the positional relationship between the images cannot be specified with reference to the edge of the image. In addition, although a large-sized printed material includes a plurality of small slices, the boundary between each small slice and a blank portion is not clear, so that the positional relationship of each print content cannot be specified based on the boundary. For this reason, for example, it cannot be confirmed that there is no printing misalignment between the position where the number 102 is printed and the position where the security mark 103 is printed, and the printed matter inspection cannot be completed.

  In such a case, there is a method in which a mark to be registered is printed on a sheet to be inspected, that is, a large-sized printed material, and the positional relationship of each print content is specified using this register. However, in this method, it is necessary to request the user of the printed matter inspection apparatus to print a mark on the printed matter. Further, since it is necessary to print marks on all printed materials to be inspected, the cost for ink and the like increases.

  The present invention has been made to solve the above-described problems of the prior art, and even if there is no print content that is commonly included in two images captured under two types of inspection light, this 2 An object of the present invention is to provide a printed matter inspection method and a printed matter inspection apparatus capable of completing a printed matter inspection using two images.

  In order to solve the above-described problems and achieve the object, the present invention performs a printed matter inspection by comparing the optical characteristics of the surface of the printed matter placed on the inspection table with a plurality of wavelengths and the reference data serving as a printing reference. A printed matter inspection method to be performed, an inspection reference mark whose position can be specified by all of a plurality of wavelengths, and a first inspection light irradiation step for irradiating a first inspection light to a printed matter placed on the inspection table, A first image capturing step for capturing a first image including a printed matter and an inspection reference mark under the first inspection light; and a second inspection light having a wavelength different from that of the first inspection light for the inspection reference mark and the printed matter. A second inspection light irradiation step of irradiating; a second image imaging step of capturing a second image including a printed material and an inspection reference mark under the second inspection light; and a position of predetermined print content on the first image. And the position of the printed content A first print range specifying step for specifying a print range based on the first print range, and a first print range inspection for checking a print content included in the first image based on the print range specified by the first print range specifying step. Specify the relative positional relationship between the printed material inspection step and the printed material range specified by the first printing range specifying step and the inspection reference mark, and specify the printed material range on the second image based on the positional relationship A second print range specifying step, and a second print inspection step for inspecting the print content included in the second image based on the range of the print specified by the second print range specification step. It is characterized by.

  Moreover, the present invention is characterized in that in the above invention, the inspection reference mark is provided on the inspection table.

  Further, the present invention is characterized in that, in the above-mentioned invention, the printed content on the printed material that can be recognized on the first image cannot be recognized on the second image.

  Also, in the present invention according to the present invention, the inspection reference mark includes a first area that is recognizable on the first image and a second area that is recognizable on the second image. Features.

  Further, according to the present invention, in the above invention, the inspection reference mark is a light emission that can emit light at a first wavelength that is recognizable on the first image and a second wavelength that is recognizable on the second image. It is formed by a unit.

  In the invention described above, the present invention is characterized in that a plurality of inspection reference marks are provided.

  In the invention described above, the present invention is characterized in that infrared rays are used as the first inspection light and ultraviolet rays are used as the second inspection light.

  In the first aspect of the present invention, in the first printing range specifying step, the partial region image on the inspection standard image included in the standard data is used as a position reference image, and the position reference image is detected by pattern matching on the first image. The position is specified, and the range of the printed matter is specified based on the position of the specified position reference image.

  Further, the present invention is the above-described invention, wherein the printed matter is a large-sized printed matter formed by a plurality of small pieces obtained by repeatedly printing the same print content at regular intervals, and a margin between the small pieces. One image and the second image are images obtained by capturing a plurality of small pieces arranged in one direction.

  Moreover, this invention is a printed matter inspection apparatus, Comprising: The 1st irradiation part which irradiates 1st inspection light with respect to printed matter, and 2nd inspection light with a wavelength different from 1st inspection light are irradiated to printed matter An inspection table having an inspection reference mark including two irradiation units, a region imaged recognizable under the first inspection light, and a region imaged recognizable under the second inspection light, and the first irradiation unit A first image pickup unit that picks up a first image including a printed matter and an inspection reference mark under the first inspection light emitted from the second printed matter and an inspection reference mark under the second inspection light emitted from the second irradiation unit. A second image pickup unit that picks up a second image including: a position of a predetermined print content on the first image, a range of the print product based on the position of the print content, and a specified print range Print on second image based on relative position with inspection reference mark An image position specifying unit for specifying the range of the print, and a print for inspecting the print content included in the first image and the print content included in the second image based on the range of the printed material specified by the image position specifying unit And an inspection processing unit.

  In the invention described above, the printed content on the printed material that can be recognized on the first image is unrecognizable on the second image, and the printed content on the printed material that can be recognized on the second image is It is unrecognizable on the first image.

  In the invention described above, the first irradiating unit irradiates infrared rays as first inspection light, and the first imaging unit images infrared light reflected from the printed matter or transmitted through the printed matter. The second irradiation unit irradiates ultraviolet rays, and the second imaging unit images visible light excited by fluorescent ink on the printed matter.

  Further, the present invention is the above invention, wherein the printed material is a large-sized printed material formed by a plurality of small pieces in which the same printing content is repeatedly printed at regular intervals, and the first image captured by the first imaging unit and The second image picked up by the second image pickup unit is an image obtained by picking up a plurality of small pieces arranged in one direction.

  According to the present invention, since the inspection reference mark common to the first image and the second image is reflected, regardless of the positional relationship between the camera that captures the first image and the camera that captures the second image. In addition, a small cut area captured in the first image and the second image is specified using the relative positional relationship with the inspection reference mark, and the print content and the print standard such as characters and patterns in the range are used as a print reference. By comparing with the data, it is possible to complete the printed matter inspection including confirmation that there is no printing misalignment.

  Further, according to the present invention, since the inspection reference mark is provided on the inspection table, it is not necessary to print the inspection reference mark on all the printed materials to be inspected, and the cost associated with the printed material is not incurred.

  In addition, according to the present invention, even if the printed content such as characters and patterns that can be recognized in common on the first image and the second image is not included in the printed matter, it is relative to the inspection reference mark. By using the positional relationship, it is possible to complete the printed matter inspection including confirmation that there is no printing misalignment.

  In addition, according to the present invention, the inspection reference mark can be recognized in the region that is recognizable in the first image captured under the first inspection light and in the second image captured under the second inspection light. Therefore, the position of the inspection reference mark can be specified in both the first image and the second image.

  In addition, according to the present invention, as the inspection reference mark, the second image is emitted at the first wavelength that is recognizable in the first image captured under the first inspection light and is imaged under the second inspection light. Since the light emitting unit that emits light at the second wavelength that is recognizable is used, the position of the inspection reference mark can be specified in both the first image and the second image.

  In addition, according to the present invention, since a plurality of inspection reference marks are provided, for example, two inspection reference marks are provided in the horizontal direction, and the inclination and image resolution of the printed material captured from the first image and the second image are determined. Information such as differences can be easily obtained.

  In addition, according to the present invention, when infrared rays and ultraviolet rays are used as inspection light, printing contents such as characters and patterns that are transferred in common to each image captured under the two inspection lights are not included. Even in this case, calculate the positional relationship between the printed content captured with the infrared light image and the printed content captured with the fluorescent image from the relative positional relationship with the inspection reference mark, and confirm that there is no print misalignment. The printed matter inspection can be completed.

  In addition, according to the present invention, the position of the position reference image is specified on the first image using the pattern matching technique, and the cut image is specified on the first image based on the relationship with the position reference image. While performing the inspection, it is possible to perform the printed matter inspection by specifying the small cutting area on the second image based on the positional relationship between the small cutting area on the first image and the inspection reference mark.

  Further, according to the present invention, when inspecting a large-sized printed material on which a plurality of small pieces are printed, even if the first image and the second image include a plurality of small pieces, By utilizing the positional relationship with the mark, it is possible to complete the printed matter inspection including that there is no printing deviation for each small piece.

FIG. 1 is a schematic diagram illustrating a schematic configuration of a printed matter inspection apparatus. FIG. 2 is a block diagram illustrating a schematic configuration of the printed matter inspection apparatus. FIG. 3 is a diagram illustrating a schematic configuration of a stage used as an inspection table on which a printed material is placed during printed material inspection. FIG. 4 is a diagram illustrating a schematic configuration of the inspection reference mark. FIG. 5 is a diagram for explaining a state in which the wire stretched on the upper frame of the stage is attached. FIG. 6 is a diagram for explaining the print contents included in each small piece on the large-format printed material. FIG. 7 is a diagram illustrating a state in which a large-sized printed material to be inspected is set on the stage. FIG. 8 is a diagram illustrating an example of an image obtained by capturing a large-sized printed material. FIG. 9 is a flowchart showing a method for inspecting printed matter. FIG. 10 is a diagram for explaining a method for specifying a small-cut range on an image obtained by capturing a large-sized printed material. FIG. 11 is a flowchart illustrating a method for performing various settings relating to the printed matter inspection. FIG. 12 is a diagram illustrating an example of a display displayed on the display unit when various settings relating to the printed matter inspection are performed. FIG. 13 is a diagram for explaining another example of the inspection reference mark provided on the stage. FIG. 14 is a diagram for explaining another example of a region constituting the inspection reference mark. FIG. 15 is a diagram for explaining a conventional printed matter inspection method.

  Hereinafter, preferred embodiments of a printed matter inspection method and a printed matter inspection apparatus according to the present invention will be described in detail with reference to the accompanying drawings. The present invention can be applied to inspection of printed matter using special ink that is not recognizable in the visible light range but can be recognized under a light source of a predetermined wavelength. Examples of such special inks include infrared absorbing ink that absorbs infrared light, ultraviolet absorbing ink that absorbs ultraviolet light, infrared transmitting ink that transmits only infrared light, and fluorescent ink that emits light upon receiving ultraviolet light. In the present embodiment, a case where a large-sized printed material including a plurality of small pieces printed using fluorescent ink is inspected will be described as an example. In the following, when describing each component, a plurality of components having the same function and operation are described using the same numerals with alphabetical symbols such as “10A, 10B”. When referring to all of the constituent parts, it is described using a reference numeral consisting only of numerals such as “10”.

  First, an outline of the printed matter inspection apparatus 1 according to the present embodiment will be described with reference to FIG. FIG. 1A is a schematic diagram illustrating a schematic configuration when the printed matter inspection apparatus 1 is viewed from the side, and FIG. 1B is a schematic view when the printed matter inspection apparatus 1 is viewed from the upper surface.

  As shown in FIG. 1A, the printed matter inspection apparatus 1 includes an ultraviolet light camera 10, an ultraviolet light irradiation unit 11, an infrared light camera 20, infrared light irradiation units 21 and 22, and a rail 50. And a stage 30 movable in the Y-axis direction (positive direction and negative direction). The stage 30 is composed of a frame body in which a glass plate 31 on which the large-sized printed material 100 is placed is fitted. On the stage 30, as shown in FIG. 1B, an inspection reference mark 39 is provided on the outer frame body of the glass plate 31. Details of the structure of the stage 30 and the inspection reference mark 39 will be described later.

  The ultraviolet light irradiation unit 11 has a function of irradiating the large-sized printed material 100 with ultraviolet light. Specifically, for example, LEDs or lamps that emit ultraviolet light are used. The ultraviolet light irradiation unit 11 is installed above the stage 30 (on the Z axis positive direction) moving on the rail 50.

  The infrared light irradiation units 21 and 22 have a function of irradiating infrared light toward the large format printed matter 100. As for the infrared light irradiation units 21 and 22, similarly to the ultraviolet light projection unit 21, the type of the light source is not particularly limited as long as infrared light can be irradiated.

  The infrared light irradiation unit 21 is installed above the stage 30 moving on the rail 50 (Z-axis positive direction). Infrared light irradiated from the infrared light irradiation unit 21 is reflected on the surface of the printed material 100 placed on the upper surface of the stage 30. On the other hand, the infrared light irradiation part 22 is installed under the stage 30 (Z-axis negative direction). The infrared light irradiated from the infrared light irradiation unit 22 passes through the glass plate 31 and the printed material 100 placed on the glass plate 31.

  The ultraviolet light camera 10 is a line camera for imaging the surface of the large-size printed material 100 irradiated with ultraviolet light by the ultraviolet light irradiation unit 11. The ultraviolet light camera 10 includes a line camera that generates an image using visible light, and an ultraviolet cut filter provided in front of the line camera. The ultraviolet light camera 10 cuts off the ultraviolet light with an ultraviolet cut filter, and images the state in which the printed content printed with the fluorescent ink receives the ultraviolet light and emits light. That is, a fluorescent image is captured by the ultraviolet light camera 10. Note that the printed matter inspection apparatus 1 has a structure that blocks other light at the time of imaging by the ultraviolet light camera 10 so that the printed content emitted under ultraviolet light can be imaged.

  An optical system including a lens is provided on the light receiving side of the ultraviolet light camera 10 so that the focal length can be adjusted according to the distance from the large-sized printed material 100 so that a clear image can be captured. It has become. However, the present invention is not limited to this, and an area camera or a line sensor may be used instead of a line camera as long as an image of the large format printed matter 100 can be generated. Further, the focal length may be adjusted by adjusting the distance between the camera and the printed material without using the optical system, in addition to adjusting the focal length using the optical system in a state where the positions of the camera and the printed material are fixed.

  As shown in FIG. 1A, the large-sized printed material 100 to be imaged is placed on the glass plate 31 of the stage 30 so that the lower side of the ultraviolet light camera 10 is placed in the Y-axis direction (positive or negative). (Direction). Thereby, the large-sized printed material 100 can be scanned using the ultraviolet light camera 10 and an image over the entire Y-axis direction can be taken.

  As shown in FIG. 1B, the large-sized printed material 100 to be subjected to print inspection in this embodiment includes three sheets in the X-axis direction (row direction) and three sheets in the Y-axis direction (column direction), for a total of nine. Small pieces 101 of sheets are printed side by side. As shown in FIG. 1B, the printed matter inspection apparatus 1 includes three ultraviolet light cameras (10A to 10C) in the X-axis direction, and images the small slices 101 for each column by each camera. . As a result, three fluorescent images corresponding to the number of columns are captured. However, the present invention is not limited to this, and a plurality of rows of images may be taken by one camera. Here, the “initial position” refers to a position when the printed material is placed on the stage 30 before the printed material is inspected.

  The infrared light camera 20 captures an infrared light reflection image that receives infrared light reflected on the surface of the large-sized printed material 100 and an infrared light transmission image that receives infrared light transmitted through the large-sized printed material 100. It is a line camera to do. The infrared light camera 20 has a line camera that receives visible light and generates an image, and a band-pass filter provided in front of the line camera. The infrared light camera 20 captures a reflected image or a transmitted image by infrared light by receiving infrared light in a predetermined wavelength region with a band-pass filter.

  For example, in the printed material inspection apparatus 1, the stage 30 on which the large-sized printed material 100 is placed moves in the positive Y-axis direction from the initial position shown in FIG. Before returning to the position, three infrared light reflection images including the inspection reference mark 39 and the three pieces 101 are reflected by three infrared light cameras (20A to 20C) and three red lights. An external light transmission image can be taken. Since the structure including the optical system, the three infrared light cameras 20A to 20C in the X-axis direction, and the like are the same as those of the ultraviolet light camera 10, detailed description thereof is omitted. Note that by using a line camera, it is possible to continuously capture images of a plurality of small pieces 101 moving under the camera in the same frame.

  FIG. 2 is a block diagram illustrating a schematic configuration of the printed matter inspection apparatus 1. The printed matter inspection apparatus 1 includes a control unit 2 and a storage unit 3 in addition to the components described with reference to FIG. The control unit 2 includes a light projection control unit 2A, a camera control unit 2B, a stage control unit 2C, an image position specifying unit 2D, and a print inspection processing unit 2E. The control unit 2 includes, for example, a CPU, a software program executed by the CPU, and various hardware controlled by the CPU that executes the software program. For storing software programs and data necessary for the operation of each unit, a memory such as a RAM and a ROM constituting the storage unit 3, a hard disk and the like are used.

  The light projection control unit 2 </ b> A has a function of controlling the ultraviolet light irradiation unit 11 and the infrared light irradiation units 21 and 22. Specifically, while a fluorescent image is captured by the ultraviolet light camera 10, the ultraviolet light is irradiated from the ultraviolet light irradiation unit 11 toward the large-sized printed material 100. Similarly, the infrared light irradiating unit 21 captures the infrared light reflected image by the infrared light camera 20 and the infrared light irradiating unit 22 captures the infrared light while capturing the infrared light transmissive image. Irradiate light. The light projecting control unit 2A performs control to turn on each light projecting unit, and also performs control to turn off other light projecting units that are not necessary for image capturing. Since the light source and the camera are arranged as shown in FIG. 1, the light source 11 for ultraviolet reflection and the light source 21 for infrared reflection are turned on simultaneously when each of the light projecting units (11, 21, or 22) is turned on. Although it is possible, the infrared reflection light source 21 and the transmission light source 22 are controlled not to be lit simultaneously.

  The camera control unit 2 </ b> B has a function of controlling the ultraviolet light camera 10 and the infrared light camera 20. Specifically, a fluorescent image, an infrared light reflection image, and an infrared light transmission image obtained by imaging the large-sized printed material 100 passing under the cameras 10 and 20 are displayed using an A / D converter (not shown). Each digitized data is stored in the storage unit 2.

  The stage control unit 2C has a function of controlling the movement of the stage 30. Specifically, for example, the stage 30 is moved by controlling a driving unit (not shown) including a gear, a motor, and the like. The stage control unit 2C has a function of calculating the position of the stage 30 that moves in the Y-axis direction from the rotation angle of a gear or a motor using, for example, a rotary encoder. The light projecting control unit 2A and the camera control unit 2B control each light projecting unit (11, 21 and 22) and each camera (10 and 20) using the position information calculated by the stage control unit 2C. .

  The image position specifying unit 2D has a function of specifying the position of each slice 101 and the inspection target region included in each slice 101 on the image generated by the ultraviolet light camera 10 and the infrared light camera 20. Have. Details of this processing will be described later.

  The print inspection processing unit 2E has a function of performing a printed matter inspection using the image of the inspection target area specified by the image position specifying unit 2D. Based on the result specified by the image position specifying unit 2D, an image of the inspection target area is extracted as measurement data from an image obtained by capturing the large-sized printed matter 100, and reference data indicating an appropriate printing state stored in the storage unit 3 and The print state is inspected by comparison. Note that the method for comparing the measurement data with the reference data and performing the printed matter inspection is the same as the conventional method, and thus detailed description thereof is omitted.

  The storage unit 3 is a storage device such as a memory or a hard disk. In the storage unit 3, programs and data necessary for realizing the functions and operations of the respective components constituting the printed matter inspection apparatus 1 are stored. The storage unit 3 includes a print inspection infrared image 3B and a print inspection fluorescent image 3C, which are reference data for comparison with measurement data when a printed material is inspected, and various types of data required for the print inspection. Print inspection data 3D including data, and printed material position data 3A used for specifying an area to be inspected are stored. Details of these data will be described later.

  The display unit 4 is a display device such as a liquid crystal display and has a function of displaying data stored in the storage unit 3, an image captured by the ultraviolet light camera 10 and the infrared light camera 20, and the like. The display unit 4 is used to display information required when various settings are added, changed, or deleted.

  The operation unit 5 has a function of accepting an instruction operation from a user when performing various processes including a printed material inspection by the printed material inspection apparatus 1. For example, when an instruction to inspect printed matter is given from the operation unit 5, this instruction information is input to the control unit 2. Based on the instruction information input from the operation unit 5, the control unit 2 controls each unit to execute each process related to the printed matter inspection. The operation unit 5 is used for inputting necessary information when various settings are added, changed, or deleted.

  Next, details of the stage 30 used in the printed matter inspection apparatus 1 will be described with reference to FIG. 3A is a diagram when the state of the stage 30 when performing the printed matter inspection is viewed from above (Z-axis positive direction), and FIG. 3B is a state when the printed matter is set on the stage 30. FIG. FIG.

  The stage 30 is configured by a glass plate 31 on which a printed material is placed and a frame body that holds the glass plate 31. The stage 30 is configured to be slidable and movable in the Y-axis direction when the groove 34 provided on the back side and the rail 50 provided in the printed matter inspection apparatus 1 are engaged with each other. The movement control of the stage 30 will be described later.

  An upper frame 32 is connected to the stage 30. The upper frame 32 is provided so as to be openable and closable with respect to the stage 30 by a hinge at the end on the back side (Y-axis positive direction). The stage 30 and the upper frame 32 are connected by dampers 36 at the left and right (X-axis positive direction and negative direction) ends, and the upper frame 32 is moved with a slight force using a handle provided on the upper frame 32. It opens upward and can be changed from the closed state of FIG. 3A to the open state of FIG. Further, the damper 36 can maintain an open state in which the upper frame 32 is lifted and opened with respect to the stage 30.

  The upper frame 32 is opened at a substantially central portion larger than the printed material so that the printed material placed on the glass plate 31 can be imaged from the upper side (Z-axis positive direction) outside in the closed state of FIG. It has a structure having an open portion. Then, three wires (35A to 35C) are stretched in the X-axis direction in the opening. The position of each wire (35A to 35C) in the Y-axis direction is adjusted to be a margin position between the small cuts 101 in each row when the upper frame 32 is closed and closed. Thereby, in the closed state, as shown in FIG. 7, the margin positions between the 101 rows of small slices are pressed against the glass plate 31 and fixed by the wires (35A to 35C). The attachment state of the wire 35 to the upper frame 32 and how to hold the printed material will be described later.

  As shown in FIG. 3A, on the left side of the stage 30, a plurality of clamps (38A to 38F) for fixing a printed material placed on the glass plate 31 are arranged in the Y-axis direction. . Similarly, a plurality of clamps (37A to 37D) are also arranged in the X-axis direction on the front side. In the open state shown in FIG. 3B, the printed material is abutted and fixed to the clamps 37 and 38, thereby positioning the printed material. The large-sized printed material 100 positioned by the clamps 37 and 38 is fixed at a position where all the small pieces 101 are on the glass plate 31.

  On the stage 30, three inspection reference marks 39 </ b> A to 39 </ b> C are fixedly provided on the inner peripheral side of the glass plate 31. The inspection reference marks 39A to 39C are provided corresponding to the columns of the small slices 101 printed on the large size printed matter 100, and at least one inspection reference mark is provided for the number of columns captured by one camera. In this embodiment, as shown in FIG. 4, the inspection reference mark 39 is positioned on the stage 30 at a position that is approximately the center in the X-axis direction in each row of the small slices 101 and the upper frame 32 shown in FIG. It is provided at a position where imaging can be performed from the outside in the direction.

  The inspection reference mark 39 is formed of a material that can be recognized on the fluorescence image and the infrared light reflection image captured by the ultraviolet light camera 10 and the infrared light camera 20. Specifically, for example, the entire inspection reference mark 39 (black portion in the drawing) shown in FIG. 4A is formed by infrared absorbing ink, and a predetermined region 139 outside the inspection reference mark 39 is emitted by ultraviolet light. Formed with fluorescent ink. As a result, in the infrared light reflection image captured using infrared light, the infrared light is absorbed by the inspection reference mark 39, so that the inspection reference mark 39 is a dark portion as shown in FIG. Is generated. On the other hand, in the fluorescence image picked up using ultraviolet light, the portion of the predetermined area 139 around the inspection reference mark 39 excites visible light by the ultraviolet light. Therefore, as shown in FIG. Only an image with a bright part is generated. Thus, by providing the inspection reference mark 39 that can be recognized in both the fluorescence image and the infrared light reflection image, the position of the inspection reference mark 39 can be specified on each image.

  If the position of the inspection reference mark 39 can be recognized on each image captured using a plurality of inspection lights, the shape of the inspection reference mark 39, the position where the inspection reference mark 39 is provided, the inspection reference mark The material etc. which form 39 are not limited to the said content. For example, the shape of the inspection reference mark 39 may be a triangle or a rectangle, or a metal such as aluminum or a resin may be used instead of ink. Further, the inspection reference mark 39 may be provided on the side or lower side of each row of the small pieces 101, or may be provided on the upper frame 32 instead of the stage 30.

  In addition to providing the reference mark 39 directly on the stage 30, the inspection reference mark 39 may be provided on a flat plate such as paper, resin or metal, and the plate may be fixed on the stage 30 for use. In this case, for example, a fixing member using a clamp or a magnet may be provided on the stage 30, and the plate including the reference mark 39 may be fixed to the stage 30 by this fixing member.

  Next, the attachment state of the wire 35 to the upper frame 32 of the stage 30 and how to hold the printed matter by the wire 35 will be described. FIG. 5 is a schematic cross-sectional view of the upper frame 32 showing how the wires 35 are attached. As shown to FIG. 5 (A), each wire 35A-35C is being fixed to the upper frame 32 by the fastener 42 at the one end side. The wire 35 extends from the fastener 42 in the X-axis direction through the cylindrical member 41 constituting a part of the upper frame 32, the wire support member 39, and the opening, and the other end is rotatably fixed to the tip of the bolt 43A. ing.

  The bolt 43 </ b> A is inserted through the through hole provided in the upper frame 32 and the inner hole of the coil spring 43 </ b> C, and is in a state of being able to advance and retract with respect to the upper frame 32. A predetermined tension is generated in the wire 35 by a coil spring 43 </ b> C between the nut 43 </ b> B engaged with the bolt 43 and the upper frame 32. The tension of the wire 35 can be adjusted by changing the position of the axial nut 43B with respect to the bolt 43A. Since the wire 35 is fixed to the tip of the bolt 43A so as to be rotatable around the X axis, the wire 35 is not twisted even if the bolt 43A is rotated.

  A region where the wire 35 is curved and contacts on the cylindrical member 41 and the wire support member 39 is formed of a curved surface so that the wire 35 is not cut due to wear or the like. Further, a shallow groove is formed in the X-axis direction at a position where the wire 35 on the cylindrical member 41 and the wire support member 39 contacts so that the wire 35 does not shift in the Y-axis direction.

  In the open state shown in FIG. 3 (B), as shown in FIG. 5 (A), the wire 35 is stretched straight in the X-axis direction at the opening of the upper frame 32. On the other hand, when it is in the closed state shown in FIG. 3 (A), that is, in the state where the large-sized printed material 100 placed on the glass plate 31 is pressed, as shown in FIG. The position in the Z-axis direction is lower than that of the large format printed material 100. Along with this, the wire 35 is deformed in the Z-axis direction between the two wire indicating members 39. At this time, the bolt 35A is pulled by the wire 35, and the coil spring 43C is compressed. Since the wire 35 is adjusted and tensioned so as to generate an appropriate tension, the large-sized printed material 100 can be pressed against the glass plate 31 and securely fixed. In addition, it is preferable that the height H from the upper surface of the printed matter 100 in the closed state shown in FIG. 5B to the lower end of the wire support member 39 is about 0.2 to 0.5 mm. Moreover, as the wire 35, a piano wire, a carbon fiber, a glass ribbon, etc. other than the wire which consists of metals, such as iron, and the alloy containing brass etc. can be utilized. The wire used for the wire 35 preferably has high tensile strength and a diameter of 0.5 mm or less.

  Next, details of the large-sized printed material 100 to be inspected will be described. As shown in FIG. 6A, a total of nine small pieces 101 of three columns from A to C in the X direction and three rows from 1 to 3 in the Y direction are printed on the large-sized printed material 100. Yes. A blank portion where nothing is printed is provided between the outer peripheral portion of the large-sized printed material 100 and each small piece 101.

  FIG. 6B is a diagram showing the print contents printed on each small slice 101. Each of the small pieces 101 is printed with a color such as a number 102, characters, patterns, and the like in color. The security mark 103 and the two-dimensional barcode 104 (hereinafter simply referred to as “barcode”) printed on the small piece 101 are printed with fluorescent ink that excites visible light with ultraviolet rays.

  In FIG. 6B, a small piece 101 is shown so that the positional relationship among the number 102, characters, patterns, security marks 103, and barcodes 104 can be understood. However, when the small slice 101 is viewed under natural light, the security mark 103 and the barcode 104 printed with fluorescent ink cannot be recognized as shown in FIG. When an infrared light reflected image is captured by the infrared light camera 20, an image shown in FIG. 6C is obtained.

  On the other hand, when other light is blocked and ultraviolet light is irradiated to emit fluorescent ink, and this is imaged by the ultraviolet light camera 10, a fluorescent image shown in FIG. 6D is obtained. In the fluorescent image, the security mark 103 and the barcode 104 printed with fluorescent ink are in a recognizable state.

  In the fluorescent image, the portion by the fluorescent ink becomes a bright portion and the other portion becomes a dark portion. For this reason, the fluorescent image actually obtained is an image obtained by reversing the image shown in FIG. However, in order to simplify the description including this figure, the visible image of the fluorescent image is represented by black and the background by white, as in the case of the infrared reflection image.

  The large-sized printed material 100 on which the small pieces 101 described in FIG. 6 are printed is placed on the glass plate 31 in a state where it abuts against the clamps 37 and 38 on the stage 30 shown in FIG. Then, at the blank portion between each row of the small slices 101, it is pressed against the glass plate 31 from above by the wire 35 stretched on the upper frame 32 and fixed as shown in FIG. At this time, all the small slices 101 set on the stage 30 and the inspection reference marks 39 provided on the stage 30 are in a state where they can be imaged from above the stage 30 (Z-axis positive direction).

  When the stage 30 is controlled by the stage control unit 2C to move in the Y-axis direction, the large format printed matter 100 is captured by the ultraviolet light camera 10 and the infrared light camera 20, and each image data is generated. In the printed matter inspection apparatus 1, a fluorescence image, an infrared light reflection image, and an infrared light transmission image are generated. In the following, the description of the fluorescence image and the infrared light reflection image will be continued to simplify the description.

  As shown in FIG. 1, the printed matter inspection apparatus 1 includes three ultraviolet light cameras 10, and three fluorescent images corresponding to each column are captured by each camera. Similarly, three infrared light reflection images corresponding to each column are picked up by the three infrared light cameras 20. Specifically, for example, an inspection reference mark 39A and three small pieces (1, A), (2, A), and (3, A) are included in a fluorescent image captured by the ultraviolet light camera 10A. included. Similarly, the infrared light reflection image captured by the infrared light camera 20A includes the inspection reference mark 39A and small cuts (1, A) to (3, A). Similarly, for images picked up by other cameras for ultraviolet light (10B and 10C) and infrared cameras (20B and 20C), inspection reference marks (39B and 39C) in each row and small slices in each row ( (1, B) to (3, B) and (1, C) to (3, C)).

  FIG. 8 shows an example of an image generated by the infrared light camera 20 and the ultraviolet light camera 10. FIG. 8A shows an example of an infrared light reflection image, and FIG. 8B shows an example of a fluorescence image. As described above, the image picked up for each column is a long and narrow image including three rows 101 of small rows 101 arranged in the Y-axis direction, as shown in FIG. The uppermost part of each image includes an inspection reference mark 39 provided corresponding to each column. As can be seen from the comparison between the infrared light reflected image and the fluorescent image shown in FIG. 8, the numbers 102, characters, and patterns that can be recognized in the infrared light reflected image do not appear in the fluorescent image. Further, the security mark 103 and the bar code 104 that can be recognized by the fluorescent image do not appear in the infrared light reflected image.

  However, in the printed matter inspection apparatus 1, the common inspection reference mark 39 is included on both the infrared light reflected image of FIG. 8A and the fluorescent image of FIG. 8B. Therefore, if the positional relationship between the small-cut range and the inspection reference mark 39 is specified on the infrared light reflection image, the positional relationship is applied to the inspection reference mark 39 on the fluorescent image, so that Also, the range of the small slice 101 can be specified. If the range of the small cut 101 can be specified, it is possible to complete the printed matter inspection including the inspection of printing deviation by comparing with the reference data as in the conventional case.

  Details of the printed matter inspection method using the inspection reference mark 39 will be described below with reference to FIGS. 9 and 10. These processes are processes performed by the image position specifying unit 2D and the print inspection processing unit 2E using the infrared light reflected image and the fluorescent image.

   FIG. 9 is a flowchart showing the flow of processing for printed matter inspection. As shown in the figure, first, the image position specifying unit 2D specifies the position of the position reference image using the infrared light reflected image shown in FIG. Here, the position reference image is a partial region image selected from print contents such as numbers, characters, and patterns printed on the small slice 101. In this embodiment, the number 102 shown in FIG.

  The position reference image is set in advance on the reference data serving as the reference for the print inspection, that is, the reference image, for each of the small slices 101 to be subjected to the print inspection, and stored in the storage unit 3 as a part of the print inspection data 3D. Has been. The image position specifying unit 2D reads information related to the position reference image from the storage unit 3, and searches for an area that matches the position reference image on the infrared light reflected image. That is, an area showing the highest correlation with the position reference image on the infrared light reflected image is specified by pattern matching, and the image in this area is set as the position reference image.

  Next, the image position specifying unit 2D specifies the range of each small slice 101 based on the specified position reference image 102 (step S2 in FIG. 9). The print inspection data 3D in the storage unit 3 includes the relationship between the position reference image and the range of the small slice 101, that is, the positional relationship between the position reference image and the outer periphery of the small slice 101. The image position specifying unit 2D reads these pieces of information from the storage unit 3 and specifies the range of the small slice 101 on the infrared light reflected image.

  Specifically, the information about the positional relationship between the position reference image and the outer periphery of the small slice is acquired when correctly printed, and the position of the number 102 on the infrared light reflected image as shown in FIG. The small cut range 105 is specified with reference to. At this time, the image position specifying unit 2D sets the coordinates of the upper left corner of the small cut range 105 as the infrared image small cut base point 115, and stores this in the storage unit 3 as a part of the printed material position data 3A.

  Next, the image position specifying unit 2D specifies the positional relationship between the small cut area 105 and the inspection reference mark 39 on the infrared light reflected image (step S3 in FIG. 9). More specifically, the relative positional relationship between the infrared image small cut base point 115 and the inspection reference mark 39 is specified and stored in the storage unit 3 as a part of the printed material position data 3A.

  As described above, when each small cut area 105 is specified on the infrared light reflection image, the print inspection processing unit 2E cuts out the image of the small cut 101 from the infrared light reflection image and performs the printed matter inspection (step S4). ). The print inspection processing unit 2E compares the characteristics of the image of the small cut range 105 cut out from the infrared light reflected image with the print inspection infrared image 3B which is the inspection reference image stored in the storage unit 3. The printed matter is inspected as before.

  A series of processing (steps S1 to S4 in FIG. 9) for specifying the small-cut area 105 using the position reference image and inspecting the printed material using the image of the small-cut 101 included in this range is an unprocessed small area. While the cut 101 exists (step S5; No), the process is repeated. First, an inspection is performed on each of the three small slices 101 included in one infrared light reflection image.

  When processing is performed on the three infrared light reflection images generated from the large-sized printed material 100 in this way, and the printed material inspection is completed for all nine small pieces 101 printed on the large-sized printed material 100 (step S5; Yes), then The image position specifying unit 2D specifies the small cut area 106 on the fluorescent image (step S6).

  When the printed matter inspection using the infrared light reflection image is completed, information specifying the relative positional relationship between the infrared image small cut base point 115 and the inspection reference mark 39 for all nine small pieces 101 is stored in the storage unit 3. It is in a state where it is stored as printed matter position data 3A. The image position specifying unit 2D applies this information to the fluorescent image, and specifies the coordinates of the fluorescent image small base point 116 on the fluorescent image as shown in FIG. 10B.

  That is, on the fluorescent image shown in FIG. 10B, based on the relative positional relationship between the infrared image small cut base point 115 and the inspection reference mark 39 on the infrared light reflected image shown in FIG. The position of the fluorescence image small cut base point 116 is specified from the inspection reference mark 39. The fluorescent image small cut base point 116 indicates the coordinates of the upper left corner of the small cut 101 on the fluorescent image. Therefore, if the fluorescent image small cut base point 116 is specified, the small cut range 106 can be specified on the fluorescent image.

  When the small cut area 106 is specified on the fluorescent image, the print inspection processing unit 2E cuts out the image of each small cut 101 and inspects the printed matter (step S7 in FIG. 9). The print inspection processing unit 2E compares the characteristics of the image of the small cut area 106 cut out from the fluorescent image with the fluorescent image 3C for print inspection that is the inspection reference image stored in the storage unit 3 as in the conventional case. Perform printed matter inspection.

  A series of processes (steps S6 and S7 in FIG. 9) for specifying the small cut area 106 using the inspection reference mark 39 and inspecting the printed material using the image of the small cut 101 included in this range are unprocessed. The process is repeated while the small piece 101 exists (step S8; No). When the inspection for each of the three small slices 101 included in one fluorescent image is completed, the processing of another fluorescent image is performed.

  The three fluorescent images generated from the large-sized printed material 100 are processed in this manner, and the printed material inspection is completed for all nine small sheets 101 printed on the large-sized printed material 100 (step S8; Yes).

  Note that the printed matter inspection apparatus 1 can recognize the small cut areas 105 and 106 correctly by recognizing this even when the small cut 101 is imaged at an angle. Specifically, for example, with respect to the small slice 101 on the same image, the angle at which the image is tilted can be calculated from the shift amount in the X-axis direction of the position reference image 102 of each small slice specified by pattern matching. By specifying the small cut areas 105 and 106 based on the calculated inclination, for example, as shown in FIG. 10C, the small cut area 105 can be correctly specified even when the small chip 101 is imaged at an angle. Can do.

  As described above, information that can specify the positional relationship between the infrared light reflected image of the small slice 101 captured by the infrared light camera 20 and the fluorescent image of the small slice 101 captured by the ultraviolet light camera 10. Even if nothing is included, by providing the inspection reference mark 39 on the stage 30, it is possible to specify the cut area 105 on the infrared light reflected image and the cut area 106 on the fluorescent image. As a result, the printed matter can be inspected in the same manner as before for all print contents on the small slice 101 including the number 102, the security mark 103, the barcode 104, the characters, and the pattern shown in FIG. 6B. it can.

  Note that the printed matter inspection method described above with reference to FIG. 9 is an example, and the present invention is not limited thereto. For example, the printed matter inspection using the fluorescent image may be performed prior to the printed matter inspection using the infrared light reflection image using the security mark 103 or the like included in the fluorescent image as a position reference image. Further, the specification of the small cut area 105 on the infrared light reflection image and the specification of the small cut area 106 on the fluorescent image may be performed first, and then the printed matter inspection may be performed.

  Further, the printed matter inspection may be performed based on the positional relationship between the number 102 on the reference image and other print contents including the security mark 103 without specifying the range of the small cut 101 on the image. Specifically, for example, based on the positional relationship between the number 102 on the infrared light reflected image and the inspection reference mark 39 and the positional relationship between the inspection reference mark 39 and the security mark 103 on the fluorescent image, the number 102 and The positional relationship with the security mark 103 is calculated. Then, if this is compared with the positional relationship between the number 102 on the inspection reference image and the security mark 103, the printed matter including confirmation that there is no printing misalignment without performing processing relating to the specification of the small cut ranges 105 and 106. Inspection can be performed.

  On the image of either the infrared light reflection image or the fluorescence image, the position of the printed content such as the number 102 or the security mark 103 included in the small slice 101 is specified using the pattern matching technique, and the inspection reference mark As long as the range of the small slice 101 or the position of the print content is specified and inspected on the other image using 39, the order of processing and the content of the printed matter inspection are not particularly limited.

  As described above, the position reference image and information such as the positional relationship between the position reference image and the small cut ranges 105 and 106 are stored in the storage unit 3 as the print position data 3A or the print inspection data 3D. The data included in the printed matter position data 3A and the print inspection data 3D can be created by another device and stored in the storage unit 3, but can be created or modified on the printed matter inspection device 1. It can also be stored in the storage unit 3.

  Hereinafter, an operation for setting a position reference image or the like using the display unit 4 and the operation unit 5 included in the printed matter inspection apparatus 1 will be described with reference to FIGS. 11 and 12. FIG. 11 is a flowchart showing a flow of processing when setting a position reference image, a small cut range (105 and 106), and an inspection target area for performing printed matter inspection. FIG. 12 shows an example of display contents displayed on the display unit 4 when making these settings.

  First, a position reference image is set using one of the infrared light reflected images captured by the infrared light camera 20 provided in the printed matter inspection apparatus 1 (step S11). When one of the three captured infrared light reflection images is selected, the infrared light reflection image shown in FIG. 8A is displayed in the frame 110 of the display unit 4 as shown in FIG. Some areas are displayed. At this time, an arbitrary area can be displayed by enlarging, reducing, and moving the display image. When the number 102 included in the small slice 101 is set as the position reference image, the position reference is made on the screen by using an input device such as a mouse constituting the operation unit 5 while confirming the display on the display unit 4. An area 111 surrounding a number 102 set as an image is selected. At this time, information on the coordinates and size of the selected region 111 is displayed on the right side of the screen. It is also possible to finely adjust the position and size of the region 111 by designating the region 111 on the image displayed on the display unit 4 and then changing these coordinates and size. It is also possible to display an enlarged or reduced image on the screen.

  Next, the range of the small cut 101 is set (step S12). As shown in FIG. 12B, in the frame 110 of the display unit 4, a region 111 indicating the previously set position reference image 102 is displayed in a visible manner on the infrared light reflected image. While confirming these displays, the operation unit 5 is used to select the range 114 of the small slice 101 on the screen. On the right side of the screen, as with the setting of the position reference image, information on the coordinates and size of the selected cut area 114 is displayed. It is also possible to finely adjust the position and size of the small cut area 114 by specifying the small cut area 114 on the image displayed on the screen and then changing these coordinates and size. It is also possible to display an enlarged or reduced image on the screen.

  The cut range 114 can be set automatically as well as being set manually as described above. Specifically, when the operator presses the automatic setting button on the display unit 4, the position of the number 102 on the standard image serving as the inspection standard of the small slice 101 is based on the previously set position reference image. Identified. Based on the positional relationship between the number 102 on the reference image and the range of the small slice 101, the small slice range 114 on the infrared light reflected image is automatically calculated and displayed on the display unit 4. At this time, the coordinates and the like displayed on the right side of the screen can be changed to finely adjust the position and size of the small cut area 114.

  When the “Next” button is pressed after setting the small cut area 114 in this way, the coordinates of the infrared small cut base point 115 on the infrared light reflected image are specified, and stored together with information such as coordinates regarding the small cut area 114. Stored in part 3.

  Next, an inspection target region on the infrared light reflection image is set (step S13). When the cut area 114 is set, as shown in FIG. 12C, an infrared light reflected image of the set cut area 114 is displayed in the frame 110 on the display unit 4 screen. The image displayed on the display unit 4 can be appropriately changed by a check box 117 provided at the lower part of the frame 110 for displaying the image.

  Specifically, when an image to be displayed is selected using the check box 117, a corresponding image is displayed in the frame 110. When an infrared light image is selected by the check box 117, an infrared light reflected image in the previously set small cut area 114 is displayed.

  In addition, when a fluorescent image is selected by the check box 117, an explanation will be given with reference to FIG. 10 based on the positional relationship between the infrared short cut base 115 and the inspection reference mark 39 included in the infrared light reflected image. By the method described above, the fluorescent image small cut base point 116 and the small cut range 106 are specified on the fluorescent image, and the fluorescent image included in this range is displayed.

  When both the infrared light reflection image and the fluorescence image are selected, the fluorescence image is displayed as an overlay on the infrared light reflection image. As a result, as shown in FIG. 12C, within the frame 110, the printed content such as the number 102 included in the infrared light reflected image and the security mark 103 and the barcode 104 included in the fluorescent image are printed. Both contents are displayed.

  When the operation unit 5 is operated while confirming the display of FIG. 12C and the range 112 as the inspection target region is selected on the infrared light reflection image on the screen, the selected region 112 is displayed on the right side of the screen. Information about coordinates and size is displayed. After specifying the area 112 on the image displayed on the screen using the mouse constituting the operation unit 5, the coordinates and size values are changed to fine-tune the position and size of the area 112. You can also. It is also possible to display an enlarged or reduced image on the screen.

  Also, a plurality of areas can be set as target areas for printed matter inspection. After selecting a certain area 112 and performing a registration operation, a plurality of areas can be registered and set as inspection target areas by repeating the same operation and selecting another area 113.

  Next, an inspection target area on the fluorescence image is set (step S14). The inspection target region on the fluorescence image can be set by the same operation as that performed on the infrared light reflection image. That is, different areas can be set as the inspection target areas on the infrared light reflected image and the fluorescent image as the inspection target areas.

  Information set using the display unit 4 and the operation unit 5 is stored in the storage unit 3 as part of the print inspection data 3D. And as mentioned above, it is used when performing printed matter inspection. If the inspection target area is set in this way and only that area is inspected, only the important area can be inspected efficiently.

  In the example described above, an example in which one inspection reference mark 39 is provided for each row of the small slices 101 included in the large-sized printed material 100 has been shown, but the present invention is not limited to this. For example, a plurality of inspection reference marks 39 may be provided for each row of small pieces 101. As shown in FIG. 13A, if two inspection reference marks 39 are provided on the stage 30 for each row of the small slices 101, two inspection reference marks are provided as shown in FIG. By recognizing that the image is captured in a state in which the small slice 101 is tilted from the tilt of 39, the small slice range 105 or 106 corresponding to this tilt can be easily set. Further, the resolution of the image can be calculated and used from the actual distance between the two inspection reference marks 39 and the distance between the inspection reference marks 39 on each image. For example, even when an image used for printed matter inspection is captured by a plurality of cameras having different resolutions, it is possible to calculate the resolution of each image and perform the printed matter inspection in consideration of this.

  In addition, as described with reference to FIG. 4, the inspection reference mark 39 is formed of infrared absorbing ink, and the predetermined region 139 around the inspection reference mark 39 is formed of fluorescent ink whose visible light is excited by ultraviolet light. Although an example has been shown, the present invention is not limited to this. For example, as shown in FIG. 14A, the inspection reference mark 39 may be formed separately in an infrared absorbing ink region 121 and a fluorescent ink region 122 that emits ultraviolet light. Further, the shape of the inspection reference mark 39 and the material forming the inspection reference mark 39 are not particularly limited as long as the position can be specified on each image captured by the printed matter inspection apparatus 1 using a plurality of inspection lights. For example, the mark shape may be a circle or the like, or a metal or resin that can be imaged under each inspection light instead of ink.

  Moreover, although the example which utilizes two test | inspection light of infrared light and ultraviolet light was shown in the example mentioned above, this invention is not limited to this. For example, when three types of inspection light are used, if the print contents such as numbers and patterns included in the small slice 101 are captured only under one of the inspection lights, for example, FIG. As shown, the inspection reference mark 39 may be formed by three regions (121 to 123) provided so that any one region is recognizable and imaged under each inspection light. Similarly, when four types of inspection light are used, an inspection reference mark 39 formed by four regions (121 to 124) may be used as shown in FIG.

  At this time, if an area that can be recognized by a plurality of inspection lights can be formed on the inspection reference mark 39, the number of areas for forming the inspection reference mark 39 can be smaller than the number of inspection lights. . Specifically, for example, three types of inspection light are used. If the region 121 constituting the inspection reference mark 39 can be recognized under two types of inspection light, as shown in FIG. An inspection reference mark 39 formed from two regions (121 and 122) can be used. In addition, the inspection reference mark 30 may not be divided if a recognizable region can be formed by all three types of inspection light.

  In this way, by dividing the inspection reference mark 39 into a plurality of areas so as to be imaged so as to be recognizable under all inspection light, a printed matter inspection can be performed in the same manner as described above. Even when the printed matter inspection apparatus 1 performs inspection for a plurality of types of printed matter, an inspection reference mark 39 that can be used for all types of printed matter is provided in consideration of ink and inspection light used for each printed matter. Then, it is possible to perform all printed matter inspections using the same inspection reference mark 39.

  Further, since the range of the small slice is obtained from the base points 115 and 116 of the image, it is possible to inspect all the small slices by setting the inspection region in one small slice image.

  Further, the inspection reference mark 39 may be configured using a light emitting element such as an LED instead of ink, resin, metal or the like. If a light emitting element such as an LED element is controlled and turned on so that the position of the inspection reference mark 39 can be recognized under each inspection light and does not interfere with the inspection, the printed matter is inspected in the same manner as described above. be able to. In addition, the printed matter inspection can be similarly performed when the filter is controlled so as to be imaged under each inspection light by using a light emitting element that emits multi-wavelength light, a filter, and the like. By configuring the inspection reference mark 39 as a light emitting unit including such light emitting elements and filters, it is possible to cope with inspection light having various wavelengths.

  As described above, according to the present embodiment, when performing a printed matter inspection using a plurality of images obtained by imaging a printed matter on a printed matter, printing of numbers, characters, and the like that are commonly imaged under each inspection light Even when the contents are not included in the printed matter, by providing the inspection reference mark 39 on the stage 30 on which the printed matter is placed, the numbers and characters included in each image are based on the positional relationship with the inspection reference mark 39. The printed matter inspection including the positional relationship inspection such as the above can be performed. At this time, even when the camera for picking up the printed matter differs for each inspection light, the printed matter inspection including the confirmation that there is no printing misalignment is specified by identifying the positional relationship such as numbers and characters from the positional relationship with the inspection reference mark 39. It can be carried out.

  Further, since the inspection reference mark 39 is provided not on the printed matter but on the stage 30 provided in the printed matter inspection apparatus 1, it is not necessary to print the inspection reference mark 39 on all the printed matters to be inspected, thereby reducing the cost. Can be suppressed.

  Further, even when there are a plurality of types of printed materials to be inspected, if the inspection reference marks 39 corresponding to all types of printed materials are used, the printed materials can be easily printed without having to change the inspection reference marks 39 according to the types of printed materials. Inspection can be performed.

  Even when not all types of printed matter are supported, if the inspection reference mark 39 is provided on a plate of paper, resin, metal, etc., and this plate is fixed on the stage 30 and used, it corresponds to the type of printed matter. With a small number of plates, all types of printed material inspection can be handled. Since the plate provided with the inspection reference mark 39 can be easily switched and used, it is possible to easily cope with inspection of various types of printed matter.

  As described above, the printed matter inspection method and the printed matter inspection apparatus according to the present invention are useful when inspecting a printed matter using a plurality of types of inspection light.

DESCRIPTION OF SYMBOLS 1 Printed product inspection apparatus 2 Control part 2A Light projection control part 2B Camera control part 2C Stage control part 2D Image position specification part 2E Print inspection process part 3 Memory | storage part 4 Display part 5 Operation part 10 Camera for ultraviolet light 11 Ultraviolet light light projection part 20 Infrared cameras 21 and 22 Infrared light projector 30 Stage 31 Glass plate 39 Inspection reference mark 100 Large format print 101 Small cut

Claims (15)

A printed matter inspection method for inspecting a printed matter by comparing the optical characteristics of a plurality of wavelengths on the surface of the printed matter placed on the inspection table with reference data serving as a printing reference,
A first inspection light irradiation step of irradiating a first inspection light to an inspection reference mark whose position can be specified by all of the plurality of wavelengths and a printed matter placed on the inspection table;
A first image capturing step of capturing a first image including the printed matter and the inspection reference mark under the first inspection light;
A second inspection light irradiation step of irradiating the inspection reference mark and the printed matter with a second inspection light having a wavelength different from that of the first inspection light;
A second image capturing step of capturing a second image including the printed matter and the inspection reference mark under the second inspection light;
A first print range specifying step of specifying a position of a predetermined print content on the first image and specifying a range of the printed matter based on the position of the print content;
A first printed matter inspection step of inspecting a print content included in the first image based on the range of the printed matter specified by the first print range specifying step;
A relative positional relationship between the range of the printed matter specified by the first printing range specifying step and the inspection reference mark is specified, and the range of the printed matter is defined on the second image based on the positional relationship. A second printing range identifying step to identify;
A printed matter inspection method comprising: a second printed matter inspection step for inspecting a print content included in the second image based on the range of the printed matter specified by the second print range specifying step. .   The printed matter inspection method according to claim 1, wherein the inspection reference mark is provided on the inspection table.   The printed matter inspection method according to claim 1, wherein the printed content on the printed matter that can be recognized on the first image cannot be recognized on the second image.   The inspection reference mark includes a first area that is recognizable on the first image and a second area that is recognizable on the second image. 4. The printed matter inspection method according to any one of 3 above.   The inspection reference mark is formed by a light emitting unit that can emit light at a first wavelength that is recognizable on the first image and a second wavelength that is recognizable on the second image. The printed matter inspection method according to any one of claims 1 to 4, wherein   The printed matter inspection method according to claim 1, wherein a plurality of the inspection reference marks are provided.   The printed matter inspection method according to claim 1, wherein infrared rays are used as the first inspection light and ultraviolet rays are used as the second inspection light. In the first printing range specifying step,
Using the partial area image on the inspection standard image included in the standard data as a position reference image, the position of the position reference image is specified by pattern matching on the first image, and the position reference image of the specified position reference image is specified. The printed matter inspection method according to claim 1, wherein a range of the printed matter is specified based on a position.   The printed matter is a large-sized printed matter formed by a plurality of small slices in which the same print content is repeatedly printed at regular intervals, and margins between the small slices, and the first image and the second image are The printed matter inspection method according to claim 1, wherein the printed image is an image obtained by imaging the plurality of small pieces arranged in one direction. A first irradiation unit that irradiates the printed material with the first inspection light;
A second irradiation unit that irradiates the printed matter with second inspection light having a wavelength different from that of the first inspection light;
An inspection table having an inspection reference mark including an area that is imaged recognizable under the first inspection light and an area that is imaged recognizable under the second inspection light;
A first imaging unit that captures a first image including the printed matter and the inspection reference mark under the first inspection light irradiated from the first irradiation unit;
A second imaging unit that captures a second image including the printed matter and the inspection reference mark under the second inspection light irradiated from the second irradiation unit;
A position of a predetermined print content is specified on the first image, a range of the printed matter is specified based on the position of the print content, and a relative position between the specified range of the printed matter and the inspection reference mark An image position specifying unit for specifying a range of the printed matter on the second image based on a relationship;
A print inspection processing unit that performs inspection of the print content included in the first image and inspection of the print content included in the second image based on the range of the printed matter specified by the image position specifying unit; A printed matter inspection apparatus comprising:   The printed content on the printed material that can be recognized on the first image cannot be recognized on the second image, and the printed content on the printed material that can be recognized on the second image is on the first image. The printed matter inspection apparatus according to claim 10, wherein the printed matter inspection device cannot recognize the printed matter.   The inspection reference mark is formed by a light emitting unit capable of emitting light at a first wavelength that is recognizable on the first image and a second wavelength that is recognizable on the second image. The printed matter inspection apparatus according to claim 10, wherein the printed matter inspection device is a printed matter inspection device.   The printed matter inspection apparatus according to claim 10, wherein a plurality of the inspection reference marks are provided.   The first irradiation unit irradiates infrared light as the first inspection light, and the first imaging unit images infrared light reflected from the printed matter or transmitted through the printed matter, and the second The printed matter inspection according to any one of claims 10 to 13, wherein the irradiation unit irradiates ultraviolet rays, and the second imaging unit images visible light excited by fluorescent ink on the printed matter. apparatus. The printed matter is a large-sized printed matter formed by a plurality of small prints in which the same printing content is repeatedly printed at regular intervals, and is picked up by the first image pick-up unit and the second image pick-up unit. The printed material inspection apparatus according to claim 10, wherein the second image to be obtained is an image obtained by capturing a plurality of the small pieces arranged in one direction.

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