JP2012022455A - Image processing inspection system of printing medium, genuineness determination method of printing medium and imaging apparatus suitable therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing inspection system for easily determining genuineness of a printing medium at a low cost.SOLUTION: A genuine printing medium 2 is printed with a first pattern 27a with a first ink, which contains a pigment that absorbs infrared ray and a color variable pigment, and a second pattern 27b with a second ink, which contains a pigment that reflects infrared ray and a color variable pigment on a surface thereof. The printing medium 2 is subjected to imaging several times while changing the irradiation angle of the visible light and the infrared ray respectively to take images of the surface thereof and every image data are compared with data of the first pattern and the second pattern. When any of the first image data includes data on the first pattern and data on the second pattern and any of the second image data does not include data on the first pattern but includes data on the second pattern, or when any of the second image data does not include data on the second pattern but includes data on the first pattern, the object is determined as genuine printing medium.

Description

  The present invention relates to an image processing inspection system for a printing medium printed using a special function ink such as pearl ink, a method for authenticating the printing medium, and an imaging apparatus suitable for them.

  Conventionally, in order to judge the authenticity of printing media such as securities, lotteries, gift certificates, etc., it has been proposed to conceal specific information in a part of a color variable printing layer such as pearl ink. (For example, refer to Patent Document 1). Further, it has been proposed to print a mark for authenticity determination on the color variable printing layer using an ink that emits fluorescence by ultraviolet rays or infrared rays (for example, see Patent Document 2). . Furthermore, it is also proposed to print another authenticity determination mark on top of the authenticity determination mark using infrared absorbing ink by using an ink that does not absorb infrared light (for example, patent document). 3).

  As the color variable printing layer, in addition to the pearl ink, special functional inks such as OVI (Optically Variable Inks) ink, cholesteric liquid crystal ink, metallic ink such as gold ink and silver ink can be used. However, the printed pattern using these special function inks shows a predetermined pattern only when observed from a specific direction using light reflection and interference, and a different pattern when observed from another specific direction. It is printed so that it can be seen. For example, when illumination is performed from a direction substantially perpendicular to the printing surface, the reflectance is increased so that almost no pattern can be observed.

  Therefore, when a print pattern is imaged using a conventional imaging device in which the positional relationship between the light source and the image sensor is fixed, the pattern that should be imaged may not be imaged. Was not easy. The same applies to the case where a mark for authenticity determination is printed on the color variable printing layer using infrared absorbing ink or infrared reflecting ink, and the specific color is reflected by the color variable printing layer. Due to the influence of the infrared rays, there are cases where it is not possible to image the authenticity determination mark drawn using the infrared absorbing ink or the infrared reflecting ink.

  By the way, the authenticity judgment technique is not limited to the above-mentioned securities and the like, and is becoming necessary in the field of product packages such as pharmaceuticals and tobacco. That is, it is necessary to identify and eliminate a counterfeit product or a counterfeit product in which an imitation product with inferior quality is packaged in the same manner as the real product. However, unlike securities, the cost of image processing inspection systems and the like cannot be very high with regard to authenticating the package of these products. In addition, it is desired that authenticity can be easily performed at the site where products are handled.

JP 2000-6564 A JP 2002-274000 A JP-A-8-153233

  The present invention has been made to solve the above-described problems of the conventional example, and is an image processing inspection system and a printing medium authenticity judgment method capable of easily authenticating a printing medium at a relatively low cost. It is another object of the present invention to provide an imaging apparatus suitable for them.

  In order to achieve the above object, an image processing inspection system for a printing medium according to an aspect of the present invention includes a first pattern printed with a first ink containing a pigment that absorbs infrared rays and a color variable pigment on the surface; A genuine print medium having a second pattern printed with a second ink containing a pigment that reflects infrared rays and a color variable pigment, and a pattern printed on a predetermined area of the surface of the print medium to be verified Authenticating whether the appraisal target print medium is a genuine print medium using an image pickup apparatus that picks up an image using visible light and infrared light and image data output from the image pickup apparatus An image processing inspection system for a print medium including a determination device, wherein the imaging device irradiates visible light in a state where infrared light is shielded on a surface of the print medium to be verified, and sets an irradiation angle of the visible light. Change While taking a plurality of first images of the surface of the print medium to be verified, the surface of the print medium to be verified is irradiated with infrared light in a state where visible light is shielded, and the irradiation angle of the infrared light is changed. The authenticity determination device captures the plurality of first image data and the plurality of second image data with respect to the first pattern and the plurality of second image data, respectively. Compared with the data relating to the second pattern, any one of the plurality of first image data includes data relating to the first pattern and data relating to the second pattern, and any one of the plurality of second image data. If data relating to the first pattern is missing and data relating to the second pattern is included, or any of the plurality of second image data includes Pattern data missing about, if it contains data for the first pattern, determines the appraisal object print medium as authentic print media.

  In the print medium image processing inspection system, the authenticity determination device preferably binarizes the second image data obtained from the imaging device using a predetermined threshold.

  Moreover, it is preferable that the authenticity determination device performs binarization processing of the second image data a plurality of times while changing a threshold value.

  The color variable pigment is preferably a pearl pigment.

  According to another aspect of the present invention, there is provided a method for authenticating a print medium, wherein the first pattern is printed with a first ink containing a pigment that absorbs infrared rays and a color variable pigment on the surface of the authentic print medium. At the same time, the second pattern is printed with a second ink containing a pigment that reflects infrared rays and a color variable pigment, and visible light is irradiated on the surface of the print medium to be verified to shield the infrared light. And imaging a plurality of first images on the surface of the appraisal target print medium while changing the irradiation angle of the visible light, and irradiating infrared light in a state where the visible light is shielded on the surface of the appraisal target print medium Then, a plurality of second images on the surface of the appraisal target print medium are captured while changing the irradiation angle of the infrared light, and the first pattern and the second pattern are included in any of the plurality of first images. And the plurality of second When the first pattern is not included in any of the images and the second pattern is included, or data regarding the second pattern is missing in any of the plurality of second images, and the first pattern In the case where the data on the appraisal is included, the appraisal target print medium is determined to be an authentic print medium.

  In the print medium authenticity determination method, the authenticity determination device preferably binarizes the second image data obtained from the imaging device using a predetermined threshold.

  Moreover, it is preferable that the authenticity determination device performs binarization processing of the second image data a plurality of times while changing a threshold value.

  The color variable pigment is preferably a pearl pigment.

  Further, an imaging apparatus according to still another aspect of the present invention is an imaging apparatus suitable for any one of the above-described image processing inspection system for print media or a method for authenticating print media, and is an object to be verified. A light-shielding body that is in close contact with the surface of the print medium or covers at least part of the surface of the print medium to be verified, and shields visible light and infrared light, and imaging that images the surface of the print medium to be verified from a direction perpendicular thereto An illumination device capable of irradiating visible light and infrared light at a plurality of illumination angles different from perpendicular to the element, the surface of the print medium to be verified, and the illumination device to control the plurality of illumination angles Irradiate visible light sequentially from each of the above, and output a plurality of first image data by visible light on the surface of the print medium to be verified, and irradiate infrared light sequentially from each of the plurality of irradiation angles, Serial comprises appraisal an imaging control unit for outputting a plurality of second image data by infrared light on the surface of the target printing medium, a storage unit for storing the plurality of first image data and the plurality of second image data.

  In the imaging apparatus, the illumination device includes a plurality of LED arrays in which a plurality of LEDs are arranged in a ring shape, and a plurality of rows of light guides arranged concentrically, and a plurality of inclined surfaces at a distal end portion of the light guide. It is preferable that the reflecting surface formed by the above is formed, and the rear end surface of the light guide is opposed to a plurality of LED arrays arranged in an annular shape.

  The light shielding body is a light shielding cylinder that is in close contact with the surface of the appraisal target print medium, and the imaging device further includes an imaging lens, with the tip of the light shielding cylinder in contact with the appraisal target print medium. It is preferable that the surface of the verification target print medium is an object-side focal position of the imaging lens, and the imaging element is an image-side focal position.

  According to the present invention, since the first pattern is printed using the first ink containing the pigment that absorbs infrared rays and the color variable pigment, when the visible light is irradiated as the illumination light, the color variable pigment causes the visible light to be visible. Is reflected, and a pattern drawn using the first ink is imaged. Moreover, when infrared rays are irradiated as illumination light, infrared rays are absorbed in the portion where the first pattern is printed, and the infrared rays are not reflected from the portion, or the amount of reflected light is reduced and becomes darker (black) than the surroundings. . On the other hand, since the second pattern is printed using a second ink containing a pigment that reflects infrared rays and a color variable pigment, a pattern drawn using the second ink when irradiated with visible light as illumination light. Is imaged. Further, when infrared light is irradiated as illumination light, the infrared light is reflected in the portion where the second pattern is printed, and the amount of reflected light is larger than the amount of reflected light from other portions, so that it is brighter (whiter) than the surroundings. )Become. Therefore, when the second image data obtained by the imaging device is binarized using a predetermined threshold value, data relating to the first pattern is lost from the second image data depending on the setting of the threshold value, and data relating to the second pattern. Can also remain. On the contrary, it is possible to cause the data related to the second pattern to be missing from the second image data and to leave the data related to the first pattern. Further, the binarization process of the second image data can be performed a plurality of times by changing the threshold value. By performing these processes as appropriate, authenticity can be determined.

1 is a diagram illustrating a configuration of an image processing inspection system for a print medium according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a print medium according to the first embodiment. Sectional drawing which shows the structure of the image processing inspection apparatus in 1st Embodiment. The figure which shows the structure of the image processing test | inspection system of the printing medium which concerns on 2nd Embodiment of this invention. FIG. 10 is a diagram illustrating an example of a print medium according to a second embodiment. Sectional drawing which shows the structure of the imaging device in 2nd Embodiment.

(First embodiment)
An image processing inspection system for a print medium and a method for authenticating a print medium according to a first embodiment of the present invention will be described. FIG. 1 is a diagram showing an image processing inspection system suitable for authenticity verification on sheet-like print media such as securities, lotteries, and gift certificates. FIG. 3 is a cross-sectional view showing a configuration of an image processing inspection apparatus 1 suitable for this image processing inspection system. In this system, a sheet-like print medium 2 is inserted into a dedicated image processing inspection apparatus 1, the surface of the print medium 2 is scanned, an image of the surface of the print medium 2 is taken, and a predetermined printed on the surface is obtained. Authenticates by reading the pattern. The image processing inspection apparatus 1 uses the imaging device 3 that captures an image of the surface of the print medium 2 to be verified and the image data captured by the imaging device 3 to determine the authenticity of the print medium 2 to be verified. It consists of a true / false determination device 4 and the like.

  As shown in FIG. 2, predetermined information such as a trademark 21, a company name 22, a money amount 23, a number 24, and a barcode 25 is printed on the surface of the printing medium 2 using ink that absorbs or reflects visible light. Has been. In addition, a watermark 26 is provided at a predetermined position (for example, the central portion) of the print medium 2. Furthermore, a pattern 27 for authenticating the authenticity is printed at another predetermined position (for example, the peripheral portion) of the print medium 2 using a color variable ink such as pearl ink.

  The authenticity verification pattern 27 is printed using a plurality of inks having different pigment components, and different patterns are observed depending on the observation angle or the illumination light irradiation angle. More specifically, a first ink containing a pigment that absorbs infrared rays and a color variable pigment, a second ink that contains a pigment that reflects infrared rays and a color variable pigment, and a predetermined first ink with a first ink. One pattern 27a is printed, and a predetermined second pattern 27b different from the first pattern 27a is printed with the second ink. The pigment that absorbs infrared rays and the pigment that reflects infrared rays are invisible (so-called colorless and transparent) or the same color as the surface color (such as the ground color of paper), and are selected so that they cannot be directly recognized by the naked eye. The position, size, and specific contents of the first pattern 27a and the second pattern 27b are not particularly limited, and may be an identification code such as a one-dimensional barcode or a two-dimensional barcode, or identification of a figure or a symbol. It may be a mark.

  When the print medium 2 to be verified is inserted into the image processing inspection apparatus 1, the image processing inspection apparatus 1 irradiates the surface with visible light and infrared light, and the surface of the print medium 2 is imaged by an imaging element such as a CCD. An image is taken and the first pattern 27a and the second pattern 27b are read. Since the first ink and the second ink each reflect visible light, the image captured by the image sensor includes the first pattern 27a and the second pattern 27b, and the image data includes the first pattern 27a and the second pattern 27b. Information on the two patterns 27b is included. However, the color variable pigment uses interference or the like so that the color changes depending on the viewing angle, or a specific pattern is visible or invisible.

A pearl pigment, which is an example of a color variable pigment, is a half-layer transparent thin film formed by applying a metal oxide having a higher refractive index to a substrate surface such as mica, SiO ₂ , or Al ₂ O _3. It is a transparent plate pigment. Light reflected from the surface of the metal oxide layer, light transmitted through the metal oxide layer and reflected from the substrate surface, light transmitted through the substrate and reflected from the interface between the substrate and another metal oxide layer, etc. By interfering with each other, light of a specific wavelength is strengthened, and light of another specific wavelength cancels out, thereby expressing a pearly luster. Further, since the pearl pigment is oriented in layers in the ink, it has a property of reflecting incident light according to Snell's law. Therefore, depending on the refractive index and film thickness of the substrate or metal oxide, the wavelength of incident light, and the incident angle, light incident from a specific angle is reflected in a state in which the intensity is increased by interference and enters the image sensor. . If the intensity of the light incident on the image sensor is too higher than a predetermined threshold, the charge accumulated in the pixels of the image sensor overflows, and reproducible or image processable image data cannot be obtained.

  As shown in FIG. 3, the casing 11 of the image processing inspection apparatus 1 has a sealed structure so as to shield outside light, and also serves as a light shielding body of the imaging apparatus 3. Inside the housing 11, a plurality of illumination devices 12 such as LED arrays 12 a and 12 b constituting the imaging device 3, a lens array 13, an imaging device 14 such as a line CCD, and the print medium 2 are drawn into the housing 11. The authenticity determination device 4 (details will be described later) including a roller 15, a monitor device 16, a CPU, a memory, and the like are provided. Among the memories of the authenticity determination device 4, a volatile memory such as a RAM temporarily stores the image data output from the image sensor 14 and also serves as a part of the image pickup device 3.

  The illuminating device 12 can switch a plurality of sets, for example, the two sets of LED arrays 12a and 12b described above, so that the irradiation angle of the illumination light applied to the surface of the print medium 2 (incident angle to the surface of the print medium 2) can be switched. It has. Moreover, each LED array 12a and 12b has two types of light sources, visible light LED for irradiating visible light, and infrared light LED for irradiating infrared rays. These two types of visible light LEDs and infrared light LEDs may be alternately arranged in a line, or the same kind of LEDs may be arranged in two lines.

  In the first embodiment, since two sets of LED arrays 12a and 12b are provided, for example, the irradiation angle (incident angle to the surface of the print medium 2) of one LED array 12a is set to 60 degrees, and the other one LED is used. The irradiation angle of the array 12a is 30 degrees. However, the number of LED arrays and the irradiation angle are examples, and the present invention is not limited to this, and three or more LED arrays may be installed. Alternatively, only one set of LED arrays may be used, and the irradiation angle of the LED arrays may be variable.

  When the print medium 2 is inserted into the insertion port 11a of the housing 11, the roller 15 is rotated in a predetermined direction, and the print medium 2 is drawn into the housing 11 and printed from one LED array 12a of the illumination device 12. The surface of the medium 2 is irradiated with visible light, and an image of the surface of the print medium 2 is captured (scanned) by the image sensor 14. As a result, the first first images of the first pattern 27a and the second pattern 27b printed on the surface of the print medium 2 are captured, and the first first image data is obtained. Next, the roller 15 is rotated in the opposite direction, and the print medium 2 is temporarily ejected to the outside of the housing 11, and the surface of the print medium 2 is irradiated from the other LED array 12 b and printed by the imaging device 14. The surface of the medium 2 is scanned. As a result, the second first image of the first pattern 27a and the second pattern 27b printed on the surface of the print medium 2 is captured, and the second first image data is obtained. Further, the roller 15 is rotated again in a predetermined direction, and the surface of the printing medium 2 is irradiated with infrared light from one LED array 12a of the illumination device 12 while the printing medium 2 is drawn into the housing 11, and the imaging device 14 scans the surface of the print medium 2. As a result, the first second image of the first pattern 27a and the second pattern 27b printed on the surface of the print medium 2 is captured, and the first second image data is obtained. Next, the roller 15 is rotated in the opposite direction to irradiate the surface of the print medium 2 with infrared light from another LED array 12b while temporarily ejecting the print medium 2 to the outside of the casing 11, and the imaging element 14 The surface of the print medium 2 is scanned. As a result, the second second image of the first pattern 27a and the second pattern 27b printed on the surface of the print medium 2 is captured, and second second image data is obtained. Each obtained image data is stored in the memory of the authenticity determination device 4 that also serves as a storage unit of the imaging device 3. Depending on the size of the first pattern 27a and the second pattern 27n and the printed position, it is not always necessary to discharge the entire print medium 2 to the outside of the housing 11, and it is fed back by a distance necessary for image reading. You can do it. When three or more LED arrays are received or when the irradiation angle of one set of LED arrays is changed in three or more steps, the above operation may be repeated as appropriate according to the number of LED arrays. Alternatively, the LED arrays 12a and 12b may each emit light alone, and then the LED arrays 12a and 12b may simultaneously emit light to obtain three pieces of first image data and three pieces of second image data.

  The authenticity determination device 4 temporarily stores a CPU that executes pattern matching, a ROM that stores information on the pattern matching program and the first pattern and the second pattern, and image data captured by the imaging device 3. It consists of RAM etc. The first pattern 27a and the second pattern 27b are printed using a first ink containing a pigment that absorbs infrared rays and a color variable pigment, and a second ink that contains a pigment that reflects infrared rays and a color variable pigment, respectively. ing. Therefore, depending on the illumination angle of the illumination light, the obtained image data may not be processed. In the present embodiment, a plurality of images are picked up by changing the type of illumination light and the illumination angle of the illumination light, and the authenticity determination device 4 first sets the plurality of first image data and the plurality of second image data, respectively. It compares with the data regarding a pattern, and the data regarding a 2nd pattern. Then, data related to the first pattern and data related to the second pattern are included in any of the plurality of first image data, and data related to the first pattern is missing in any of the plurality of second image data. When data relating to the pattern is included, or when data relating to the second pattern is missing in any of the plurality of second image data and data relating to the first pattern is included, the print medium 2 to be verified Is a genuine print medium.

  Since the first pattern 27a is printed using a first ink containing a pigment that absorbs infrared rays and a color variable pigment, when visible light is irradiated as illumination light, the visible light is reflected by the color variable pigment, A pattern drawn using one ink is imaged. Further, when infrared light is irradiated as illumination light, the infrared light is absorbed in the portion where the first pattern 27a is printed, and the infrared light is not reflected from the portion or the amount of reflected light is reduced, and is darker (black) than the surroundings. Become. On the other hand, since the second pattern 27b is printed using a second ink containing a pigment that reflects infrared rays and a color variable pigment, it is drawn using the second ink when irradiated with visible light as illumination light. A pattern is imaged. Further, when infrared light is irradiated as illumination light, the infrared light is reflected at the portion where the second pattern 27b is printed, and the amount of reflected light is larger than the amount of reflected infrared light from other portions, so that it is brighter than the surroundings ( White). Therefore, when the second image data obtained from the imaging device 3 is binarized using a predetermined threshold value, data related to the first pattern is lost from the second image data depending on the setting of the threshold value, and the second pattern data is related to the second pattern. If data can be left, conversely, data relating to the second pattern can be lost from the second image data, and data relating to the first pattern can remain. Further, the binarization process of the second image data can be performed a plurality of times by changing the threshold value. By performing these processes as appropriate, authenticity can be determined.

  When the contents of the first pattern 27a and the second pattern 27b can be easily confirmed by the operator's visual observation such as predetermined figures and symbols, the image data captured by the imaging device 3 is output to the monitor device 16 as it is. . An image of the surface of the print medium 2 obtained by first irradiating visible light is displayed on the screen of the monitor device 16 as a first image. Next, an image of the surface of the print medium 2 obtained by irradiating infrared light is displayed on the screen of the monitor device 16 as a second image. When the first pattern 27a and the second pattern 27b are displayed as the first image and only the first pattern 27a or only the second pattern 27b is displayed as the second image on the screen of the monitor device 16, or When the above binarization process is performed a plurality of times while changing the threshold value, when both the first pattern 27a and the second pattern 27b are displayed, the handler determines that the print medium is genuine, and not so. Sometimes it can be determined to be fake.

  On the other hand, if the contents of the first pattern 27a and the second pattern 27b cannot be easily confirmed by the operator's visual observation such as a barcode, the image data captured by the imaging device 3 is input to the authenticity determination device 4, Predetermined image processing is performed. As a result of image processing such as pattern matching, it is confirmed that data related to the first pattern 27a and the second pattern 27b exists in any of the plurality of first image data, and any one of the plurality of second image data. When it is confirmed that only the first pattern 27a, only the second pattern 27b, or both the first pattern 27a and the second pattern 27b are present, the authenticity determination device 4 determines that the print medium 2 is genuine. If not, it is determined to be fake. Then, a predetermined warning is displayed on the screen of the monitor device 16 and / or the operator is warned by voice or flashing of an alarm lamp.

(Second Embodiment)
Next, a printing medium image processing inspection system and a printing medium authenticity evaluation method according to a second embodiment of the present invention will be described. FIG. 4 is a diagram showing an image processing inspection system suitable for authenticity verification on a three-dimensional print medium such as a product package. In this system, a handy type imaging device 6 constituting the image processing inspection apparatus 1 is brought into contact with the surface of a three-dimensional printing medium 3 to capture an image of the surface of the printing medium 5 and printed on the surface. The authenticity is verified by reading the predetermined pattern.

  As shown in FIG. 5, the printing medium 5 is a three-dimensional printing medium such as a paper box, for example, and the surface thereof is made of an ink that absorbs or reflects visible light, and is used for a trade name, a trademark, a company name, and a logo. A mark, a monetary amount, etc. (not shown) and a bar code 51 encoded with these are printed. Of these, metallic inks such as gold ink and silver ink are often used in addition to pearl ink for printing of trademarks and logo marks. These metallic inks contain metal powder as a pigment, have high reflectivity, and have a property of reflecting incident light according to Snell's law. Therefore, depending on the image sensor, the illumination angle of the illumination light, and the position of the printed pattern using metallic ink, the amount of light incident on the image sensor increases, and the charge accumulated in the pixels of the image sensor overflows, allowing playback or image processing. May not be obtained. Therefore, the imaging device 6 according to the second embodiment is also configured to change the illumination light irradiation angle.

  Further, in the case of a three-dimensional print medium 5 such as a product package, not only the size of the print medium 5 but also the weight of its contents is a restriction on handling. Therefore, it is preferable that at least the imaging device 6 in the image processing inspection device 1 can be held by a handler. Therefore, as shown in FIG. 4, the imaging device 6 is configured as a handy type provided separately from the monitor device 16 and the authenticity determination device 4.

  FIG. 6 shows a specific configuration of the handy type imaging device 6. The imaging device 6 includes an imaging lens 61, an imaging element 62, LED arrays 63 and 64, light guides 65 and 66, a protective cap 67, a light shielding cylinder 68 for shielding ambient light, and the like. . The imaging element 62 is provided at the image side focal position of the imaging lens 61 and is configured by a two-dimensional CCD or the like. The LED arrays 63 and 64 are arranged around the imaging lens 61, and, for example, a plurality of LEDs are arranged in a plurality of rows (for example, two rows) in a ring shape. The LED arrays 63 and 64 each have two types of light sources, a visible light LED for irradiating visible light and an infrared LED for irradiating infrared light. These two types of LEDs are arranged alternately, for example. ing.

  The light guides 65 and 66 are made of a translucent resin such as acrylic and are arranged in a plurality of rows (for example, two) concentrically. Further, the outer peripheral surface of the light guide 65 disposed on the inner side is painted with a light-shielding paint. Instead of providing the light-shielding cylinder (light-shielding body) 68, the outer peripheral surface of the light guide 66 disposed on the outside may be coated with a light-shielding paint. Reflecting surfaces 65a and 66a formed by a plurality of inclined surfaces are formed at the front ends of the light guides 65 and 66. The inner and outer diameters of the light guides 65 and 66 are set to dimensions so that the rear end surfaces of the light guides 65 and 66 can face the LED arrays 63 and 64 arranged in an annular shape, respectively.

  Further, the angles of the reflecting surfaces 65a and 66a of the light guides 65 and 66 go straight through the light guides 65 and 66, and the light reflected by the reflecting surfaces 65a and 66a has a predetermined irradiation angle (to the surface of the print medium 5). Is set to be 30 degrees and 60 degrees, for example. Further, the lengths of the light guides 65 and 66 are set so that the light reflected by the reflecting surfaces 65a and 66a irradiates the imaging target region having a predetermined diameter with a certain luminance or higher. Further, the focal lengths of the image pickup lens 61 on the object side and the image side are such that the surface of the print medium 5 is the object of the image pickup lens 61 when the protective cap 67 attached to the tip of the light shielding cylinder 68 is in contact with the print medium 5. The image pickup element 62 is set to be the focal position on the image side.

  The light output from the LED 63 or 64 travels straight inside the light guide 65 or 66, or travels inside the light guide 65 or 66 while being repeatedly reflected at the interface between the light guide 65 or 66 and air, and the reflecting surface 65a. Alternatively, the light guide 65 or 66 is reflected from the light guide 65 or 66 and is incident on the surface of the print medium 5. In addition to the illumination light having the predetermined incident angle, illumination light having other incident angles is also incident on the surface of the print medium 5, but the output light from the LED has high directivity. The illumination light having the incident angle is dominant.

  When this handy-type image pickup device 6 is brought into contact with the surface of the print medium 5 and the first pattern and the second pattern printed on the surface are read for authenticating, the visible light LED of one LED array 63 Is emitted, the image pickup device 62 picks up an image, the LED array 63 emits an infrared light LED, and the image pickup device 62 picks up an image. Next, the visible light LED of the other LED array 64 is caused to emit light and an image is taken by the imaging element 62, and the infrared light LED of the LED array 64 is caused to emit light and an image is taken by the imaging element 62. As a result, four images are continuously captured, and two pieces of first image data and second image data are obtained. Although switching of the illumination light and imaging are performed in a short time, in order to perform imaging more reliably, it is preferable to output an audio signal or the like when imaging is completed. In other words, it is preferable that the user keeps the imaging device 6 in contact with the surface of the print medium 5 until an audio signal is output. Since the processing of the first image data and the second image data in the authenticity determination device 4 is the same as that in the first embodiment, the description thereof is omitted.

  The second embodiment is not limited to the case where the second pattern is printed on the product package or the packaging film (exterior) thereof, and the interior material such as PTP (press through package) for individually mounting tablets and capsules. It can also be applied when printing on the surface. For example, when a drug is provided according to a prescription at a pharmacy in a medical institution, this image processing inspection system can be used to determine whether the drug is genuine or counterfeit. Since the printed surface on the back side of the PTP has a metallic luster, the imaging device 6 including the illumination device as described above is effective.

  Further, the angles of the plurality of inclined surfaces constituting the reflecting surfaces 65a and 66a of the light guides 65 and 66 do not have to be constant, and may be changed little by little in order. Furthermore, the light emission order of the LED arrays 63 and 64 is not particularly limited, and the visible light LED may be continuously emitted and then the infrared light LED may be continuously emitted, or vice versa. . Further, the LED arrays 63 and 64 may be made to emit light independently, and then the LED arrays 63 and 64 may be made to emit light at the same time to obtain three pieces of first image data and three pieces of second image data.

DESCRIPTION OF SYMBOLS 1 Image processing inspection apparatus 2 (Sheet form) Print medium 3 Imaging apparatus 4 Authenticity determination apparatus 5 (Stereoscopic) print medium 6 Imaging apparatus 11 Case 12 Illumination apparatus 12a, 12b LED array 13 Lens array 14 Imaging element 16 Monitor Device 27a First pattern 27b Second pattern 61 Imaging lens 62 Imaging element 63, 64 LED array 64, 65 Light guide 65a, 65b Reflecting surface 68 Light shielding cylinder

Claims (11)

A first pattern printed with a first ink containing a pigment that absorbs infrared rays and a color variable pigment on a surface, and a second pattern printed with a second ink containing a pigment that reflects infrared rays and a color variable pigment An authentic print medium having,
An imaging device that captures an image of a pattern printed on a predetermined area of the surface of the print medium to be verified, using visible light and infrared light, and
An image processing inspection system for a print medium comprising a true / false judgment device for judging whether or not the appraisal target print medium is a genuine print medium using image data output from the imaging device,
The imaging apparatus irradiates visible light in a state where infrared light is shielded on a surface of the appraisal target print medium, and a plurality of first images of the surface of the appraisal target print medium while changing an irradiation angle of the visible light. And irradiating infrared light in a state where visible light is shielded on the surface of the appraisal target print medium, and changing the irradiation angle of the infrared light, a plurality of second surfaces on the surface of the appraisal target print medium. Take an image,
The authenticity determination device compares the plurality of first image data and the plurality of second image data with data related to the first pattern and data related to the second pattern, respectively. The data regarding the first pattern and the data regarding the second pattern are included, and the data regarding the first pattern is missing in any of the plurality of second image data, and the data regarding the second pattern is included. If the data related to the second pattern is missing in any of the plurality of second image data and the data related to the first pattern is included, the appraisal target print medium is set to be authentic. An image processing inspection system for a print medium, characterized in that the print medium is determined to be a print medium.   The image processing inspection system for a print medium according to claim 1, wherein the authenticity determination device binarizes the second image data obtained from the imaging device using a predetermined threshold.   3. The print medium image processing inspection system according to claim 2, wherein the authenticity determination device performs binarization processing of the second image data a plurality of times while changing a threshold value.   The image processing inspection system for a print medium according to any one of claims 1 to 3, wherein the color variable pigment is a pearl pigment. A first pattern is printed with a first ink containing a pigment that absorbs infrared rays and a color variable pigment on the surface of the genuine print medium, and a second ink containing a pigment that reflects infrared rays and a color variable pigment is printed with the first ink. Print two patterns,
Irradiate visible light in a state where infrared light is shielded on the surface of the print medium to be verified for authenticity, and change the irradiation angle of the visible light to display a plurality of first images on the surface of the print medium to be verified. A plurality of second images of the surface of the appraisal target print medium are picked up and irradiated with infrared light in a state where visible light is shielded on the surface of the appraisal target print medium, and the irradiation angle of the infrared light is changed. Image
Any of the plurality of first images includes the first pattern and the second pattern, and any of the plurality of second images does not include the first pattern and includes the second pattern. If the data related to the second pattern is missing in any of the plurality of second images and the data related to the first pattern is included, the print medium to be verified is an authentic print medium. A method of authenticating a print medium that is judged to be   6. The method of authenticating a print medium according to claim 5, wherein the data relating to the second image is binarized using a predetermined threshold value.   7. The method of authenticating a print medium according to claim 6, wherein the binarization processing of data relating to the second image is performed a plurality of times.   The method of authenticating a print medium according to any one of claims 5 to 7, wherein the color variable pigment is a pearl pigment. An imaging apparatus suitable for the print medium image processing inspection system according to any one of claims 1 to 4 or the print medium authenticity judgment method according to any one of claims 5 to 8. There,
A light-shielding body which is in close contact with the surface of the print medium to be verified or covers at least a part of the surface of the print medium to be verified, and shields visible light and infrared light;
An image sensor for imaging the surface of the print medium to be verified from a direction perpendicular thereto;
An illumination device capable of irradiating visible light and infrared light at a plurality of irradiation angles different from perpendicular to the surface of the print medium to be verified;
The lighting device is controlled to emit visible light sequentially from each of the plurality of irradiation angles to output a plurality of first image data by visible light on the surface of the appraisal target print medium, and the plurality of irradiations An imaging control unit that irradiates infrared light sequentially from each of the angles, and outputs a plurality of second image data by infrared light on the surface of the print medium to be verified;
An image pickup apparatus comprising a storage unit that stores the plurality of first image data and the plurality of second image data. The lighting device has a plurality of LED arrays in which a plurality of LEDs are arranged in a ring shape, and a plurality of rows of light guides arranged concentrically,
10. The light guide according to claim 9, wherein a reflection surface formed by a plurality of inclined surfaces is formed at a front end portion of the light guide, and a rear end surface of the light guide is opposed to a plurality of LED arrays arranged in an annular shape. Imaging device. The light-shielding body is a light-shielding cylinder that is in close contact with the surface of the verification target print medium;
The imaging apparatus further includes an imaging lens, and the front surface of the appraisal target print medium is an object-side focal position of the image pickup lens in a state in which a tip of the light shielding tube is in contact with the appraisal target print medium, and the imaging element The image pickup apparatus according to claim 10, wherein is an image-side focal position.

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