JP2022139020A - Information recording medium, label, reading device, program and authenticity determining method - Google Patents

Abstract

To provide an information recording medium, a label, a reading device, a program and an authenticity determining method which make information printed by a transparent material not easily visually recognizable by visual inspection, and which improve precision in reading by the reading device.SOLUTION: An information recording medium 30 includes a luminance layer 31 and a transparent layer 32. The luminance layer 31 and the transparent layer 32 are formed on one surface of a base 10, and are configured to have respective different amounts of reflected light in accordance with an observation angles. The luminance layer 31 is a first image including a solid image. The transparent layer 32 is a second image including a code that has variable information formed of a transparent material. A recognition region to recognize a reading region of the code, of the second image is formed on the solid image.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to an information recording medium, a label, a reader, a program, and an authentication method.

2. Description of the Related Art Conventionally, there is a digital watermarking technique for embedding specific information in an image or the like. If this technology is used in printed matter, information can be embedded at a level that cannot be visually recognized by humans, and the artistic effect of the printed matter is not impaired. Also, the information embedded in the printed matter can be read by a reading device.

When this embedded information is used for authenticity determination, for example, it is desirable that the embedded information is difficult to be estimated from the copy. For this reason, a technology related to an information recording medium designed to make the embedded information less likely to be estimated has been disclosed (for example, Patent Document 1).

JP 2016-93895 A

In the information storage medium described in Patent Document 1, when the information to be read by the reading device is composed of transparent ink, depending on the lamination state of the lower layer and the transparent ink, noise may occur when reading by the reading device, and reading may be impossible. There was a problem that made it difficult.
Further, in order to improve the readability of information composed of transparent ink, for example, a method of thickly laminating transparent ink or printing the lower layer in a solid pattern to increase the density is conceivable. However, when these methods are adopted, there is a problem that the visibility of the transparent ink is increased by visual observation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an information recording medium or the like in which information printed with a transparent material is difficult to visually recognize and is devised to improve reading accuracy by a reading device.

The present invention solves the above problems by means of the following solutions. In order to facilitate understanding, reference numerals corresponding to the embodiments of the present invention are used for explanation, but the present invention is not limited to these. Also, the configurations described with reference numerals may be improved as appropriate, and at least a part of them may be replaced with other components.

A first invention is an information recording medium (30) comprising a first ink layer (31) and a second ink layer (32), wherein the first ink layer and the second ink layer are , provided on one surface of the base material (10), each configured so that the amount of reflected light varies depending on the observation angle, the first ink layer is a first image including a solid image (B1), and the second ink layer The ink layer is a second image containing a code having variable information formed of a transparent material, and an identification area for recognizing a reading area of the code in the second image is formed on the solid image. It is an information recording medium formed.
In a second invention based on the information recording medium (30) of the first invention, the first image further includes a pattern image (C1), and at least part of the second image is formed over the pattern image. It is an information recording medium.
A third invention is the information recording medium (30) according to the first invention or the second invention, wherein the second image includes a pattern image (C2).
A fourth invention is the information recording medium (30) according to any one of the first to third inventions, wherein the code is a two-dimensional code, and the identification area of the code is an outer peripheral frame of the code. It is an information recording medium.
A fifth invention is the information recording medium (30-2) according to any one of the first to third inventions, wherein the code is a two-dimensional code, and the identification area of the code is the code. It is an information recording body, which is a mark indicating existence.
A sixth invention is the information recording medium according to any one of the first to fifth inventions, wherein the first image includes a code image different from the second image.
A seventh invention is an information recording medium (30) according to any one of the first invention to the sixth invention, wherein the first ink layer (31) is formed of a glittering material. be.
An eighth invention is a label (1) comprising an information recording medium (30) according to any one of the first invention to the seventh invention.
A ninth invention is a reading device (5) for reading an information recording medium (30) according to any one of the first invention to the seventh invention, comprising a reading section (5C) and a reading section in the vicinity of the reading section. a light-emitting portion (5L) that emits light; and reading means (52) in which the reading portion reads an image including the second image of the information recording medium while the light-emitting portion is emitting light. ); a code area acquisition means (53) for detecting the identification area from the image read by the reading means and acquiring a code area based on the detected identification area; a code specifying means (54) for specifying the code by performing image processing on the code area.
A tenth invention is the reader (5) according to the ninth invention, wherein the code identifying means (54) divides the code area into cells and binarizes the code area using the luminance value of each cell. to identify the code.
An eleventh invention is the reader (5) according to the tenth invention, wherein the binarization process obtains an average value for each classification based on the luminance value of each cell, and converts the obtained average value to the It is a reading device that makes the luminance value of each cell belonging to the classification.
A twelfth invention is the reader (5) according to the tenth invention or the eleventh invention, wherein the binarization process is performed by dividing the brightness value of one cell and each cell located near the one cell. is a reading device that binarizes the one cell using an average value of luminance values in the above.
A thirteenth invention is the reader (5) according to any one of the ninth invention to the twelfth invention, wherein the code identifying means (54) has a pre-stored shape of the detected identification area. In this case, the reading device performs binarization processing corresponding to the shape.
A fourteenth invention is the reading device (5) according to any one of the ninth invention to the thirteenth invention, wherein the information acquisition acquires the variable information from the code specified by the code specifying means (54). A reading device comprising means (55) and information output means (56) for outputting information based on the variable information acquired by the information acquisition means to a display section (67).
A fifteenth invention is a program (61a) executed by a computer (5) for determining the authenticity of any one of the information recording mediums (30, 30-2) of the first invention to the seventh invention, reading means for reading an image including the second image of the information recording medium; and code area acquisition for detecting the identification area from the read image and obtaining a code area based on the detected identification area. means, code identifying means for performing image processing on the obtained code region to identify the code, information obtaining means for obtaining the variable information from the identified code, and when the variable information can be obtained and a program for functioning as authenticity determination means for determining that the information recording medium is true.
A sixteenth invention is a method for determining the authenticity of an information recording medium (30, 30-2) according to any one of the first invention to the seventh invention, wherein a computer (5) comprises: reading an image including a second image; detecting the identification area from the read image; obtaining a code area based on the detected identification area; and performing image processing on the obtained code area. obtaining the variable information from the identified code; and determining that the information recording body is true when the variable information is obtained. It is an authenticity determination method.

According to the present invention, it is possible to provide an information recording medium or the like in which information printed with a transparent material is difficult to visually recognize and is devised to improve reading accuracy by a reading device.

FIG. 3 is a diagram for explaining a printed matter according to the embodiment; FIG. 4 is a diagram showing an example of an image of an information recording medium according to the embodiment; FIG. FIG. 4 is a diagram showing an example of a pattern image of an information recording medium according to the embodiment; FIG. 10 is a diagram showing another example of the pattern image of the information recording medium according to the embodiment; It is a figure for demonstrating the observation mode based on the structure of the information recording medium which concerns on this embodiment. FIG. 4 is a diagram for explaining the positional relationship between an illumination light source and a camera when copying a printed matter according to the embodiment; It is a figure which shows the positional relationship of the out camera of the reader which reads the information recording medium which concerns on this embodiment, and a mobile light. FIG. 4 is a diagram showing an example of reading patterns of an information recording medium by the reading device according to the embodiment; FIG. 4 is a diagram showing a specific example of a reading pattern of an information recording medium by the reading device according to the embodiment; 3 is a functional block diagram of the reader according to the embodiment; FIG. 5 is a flowchart showing reading processing in the reading device according to the embodiment; 6 is a flowchart showing code identification processing in the reading device according to the embodiment; It is a figure for demonstrating the code specific processing in the reading device which concerns on this embodiment. It is a figure for demonstrating the binarization process in the reading device which concerns on this embodiment. It is a figure for demonstrating the binarization process in the reading device which concerns on this embodiment. It is a figure which shows the example of the image of the information recording medium which concerns on a deformation|transformation. It is a figure for demonstrating the binarization process in the reading device which concerns on a modification.

EMBODIMENT OF THE INVENTION Hereafter, the form for implementing this invention is demonstrated, referring a figure. This is just an example, and the technical scope of the present invention is not limited to this.
(embodiment)
FIG. 1 is a diagram for explaining a printed matter 1 according to this embodiment.
Each figure shown below, including FIG. 1, is a schematic diagram, and the size and shape of each part are shown by exaggerating or omitting them as appropriate for easy understanding. .
Also, in the following description, specific numerical values, shapes, materials, and the like are shown and described, but these can be changed as appropriate.
In the present invention, the term "transparent" refers to a material that transmits at least the light of the wavelength used.

<Printed matter 1>
A printed matter 1 shown in FIG. 1A is, for example, a label attached to an article. By attaching the printed matter 1 to an article, the printed matter 1 can be used for authenticity determination in product management, distribution, sales, and the like.
FIG. 1A shows a plan view of the printed matter 1 viewed from above in the vertical direction Z. FIG. The printed matter 1 includes a base 10 (substrate) and an information recording medium 30 .

<Structure of base 10>
FIG. 1(B) is a partial schematic diagram of a cross section in the XX direction in FIG. 1(A). FIG. 1B shows a cross-sectional view of the printed matter 1 viewed from the front in the Y direction. As shown in FIG. 1B, the base 10 includes a substrate layer 11, an adhesive layer 12, and a peelable support layer 13 arranged downward in the Z direction from the side having the information recording medium 30. They are stacked in this order.
For example, a resin film, a resin sheet, paper, or the like can be used for the base material layer 11 . Materials for the base material layer 11 include, for example, inkjet paper, high-quality paper, kraft paper, copy paper, glassine paper, rayon paper, coated paper, synthetic paper, paper laminated with a resin film, NIP high-quality paper, oriented polypropylene, and polyethylene. Terephthalate, oriented polystyrene, polyvinyl chloride and the like can be used. The base material layer 11 may have a flat surface capable of supporting the information recording medium 30 .

The adhesive layer 12 is made of an adhesive to be attached to an article when the printed matter 1 is used. As the adhesive layer 12, a common adhesive having an adhesive action can be widely used to form the adhesive layer. Rubber-based adhesives such as NR, SBR, IR, and CR are mainly used as solvent-based adhesives, but emulsion-type acrylic adhesives can also be used. In addition, there are silicone-based adhesives, polyvinyl ether-based adhesives, and the like, and any of them can be used.

The peelable support layer 13 protects the adhesive layer 12 in an unused state, that is, in the printed matter 1 before being attached to an article, and is provided so as to prevent the adhesive layer 12 from inadvertently sticking to other articles. It is a member called so-called release paper, release sheet, etc. In FIG. 1B, the peelable support layer 13 is shown as a single layer, but the peelable support layer 13 may be configured as a laminate of a substrate layer and a peeling layer, for example. The peelable support layer 13 is peeled off and removed when the printed matter 1 is attached to an article. For the releasable support layer 13, for example, the same material as that of the substrate layer 11 can be used, and the surface on which the adhesive layer is to be formed can be coated with ink for forming a release layer to impart releasability.

<Structure of information recording medium 30>
An information recording medium 30 is provided on the surface side of the base 10, that is, on the upper side in the Z direction. The information recording medium 30 is printed with information such as a code, which is used for authenticity determination, by latent image printing. The image printed on the information recording medium 30 is changed by changing the viewing direction of the base 10 .

As shown in FIG. 1B, the information recording medium 30 has a composite image including a bright layer 31 (first ink layer) and a transparent layer 32 (second ink layer) on the base 10 . The composite image is an image formed by a composite layer in which the bright layer 31 and the transparent layer 32 are superimposed.
The glitter layer 31 is a layer on which a first image including a solid image and a pattern image is printed with ink containing a glitter material.
The transparent layer 32 is a layer on which a second image including a two-dimensional code (code) image with a pattern image different from the pattern image of the bright layer 31 is printed with transparent ink (transparent material).
In this example, the bright layer 31 and the transparent layer 32 are square-shaped, and the transparent layer 32 is formed on the entire bright layer 31 .

Here, a method for manufacturing the information recording medium 30 will be briefly described.
First, the base 10 is prepared, and a first image is gravure-printed as the glitter layer 31 on the base 10 with glossy ink or the like containing a glitter material. Various types of ink are assumed as the ink containing the glitter material for drawing the first image, for example, as exemplified below.
For example, it may be silver ink containing aluminum powder, copper powder, zinc powder, tin powder, iron phosphide, or the like. Moreover, it may be an ink obtained by mixing a chromatic ink containing a pigment or a dye with a silver ink.

Furthermore, the glitter layer 31 may be ink of only a glitter material exhibiting bluish gold or reddish gold. Moreover, the ink of the luster material showing bluish gold or reddish gold may be mixed with the chromatic ink of the above-mentioned colored pigment.
Furthermore, pearl ink, liquid crystal ink, OVI (Optical Variable Ink), CSI (Color Shifting Ink), etc., which are inks containing functional pigments that change color by reflecting light, may also be used. Incidentally, the pearl ink is an ink containing a pearl pigment that has a pearl luster compared to ordinary pigments, and has safety, luster, and high-class feeling. Liquid crystal inks are inks containing liquid crystals that have the property of changing color with temperature.
In this example, the glitter layer 31 uses silver ink containing a glitter material.

Next, a second image as a transparent layer 32 is superimposed on the first image of the bright layer 31 using transparent ink or the like and gravure-printed. The ink for drawing the second image is, for example, achromatic ink such as matte OP varnish, transparent varnish, ink varnish, transparent ink or medium ink. These inks may be any printing inks such as ultraviolet curable inks, oxidative polymerization inks, penetrating inks, heat drying inks, and evaporation drying inks.
The materials used for the bright layer 31 and the transparent layer 32 described above are merely examples, and other materials may be used as long as the amount of reflected light varies depending on the viewing angle.

Here, the thickness of each applied ink is, for example, about 1 micrometer. In addition, the thickness of the ink is not limited to this. Also, for example, the thickness of the ink may vary depending on the material.
The above-described printing process is not limited to gravure printing, and may be wet offset printing, dry offset printing, letterpress printing, waterless lithographic printing, flexographic printing, screen printing, intaglio printing, and the like.

Next, an image printed in the printing process of the information recording medium 30 will be described.
FIG. 2 is a diagram showing an example of an image on the information recording medium 30 according to this embodiment.
3 and 4 are diagrams showing examples of pattern images of the information recording medium 30 according to this embodiment.

FIG. 2A shows a mode in which the second image of the transparent layer 32 is superimposed on the first image of the bright layer 31 . The first image includes an image B1 that is a solid image and an image C1 that is a pattern image. The image B1 forms the outer frame, and the image C1 forms the microcharacters. Also, the second image includes an image C2 that is a pattern image. The image C2 forms an image including a two-dimensional code typified by a QR code (registered trademark).
As shown in FIG. 2(B), an identification area of an image C2, which is an outer frame of a two-dimensional code, which is a part of the second image, is superimposed on the image B1.

Next, regarding the printing of the images C1 and C2 shown in FIG. 2A, the printing condition in which the area that can hide the background is expressed in % is defined as the area ratio. described as a rate.
FIG. 3A shows a part of the image C1 of the bright layer 31 and an enlarged view of a region E1 which is a part thereof. The image C1 is a pattern image in which a foreground portion C1a and a background portion C1b are expressed in binary, as shown in an area E1.
For example, the foreground portion C1a is printed with a halftone dot area ratio of 100%, and the background portion C1b is printed with a halftone dot area ratio of 75%, for example. However, this ratio is an example and is not limited to this. For example, the dot area ratio of the foreground portion C1a may be less than 100%, and the dot area ratio of the background portion C1b may be other than 75%. In that case, it is desirable to set the difference in halftone dot area ratio between the foreground portion C1a and the background portion C1b to 15% or more and 50% or less. Also, the density of the foreground portion C1a and the background portion C1b may be reversed.
Note that the image B1, which is a solid image, is printed with a halftone dot area ratio of 100% over the entire image B1.

FIG. 3B shows a part of the image C2 of the transparent layer 32 and an enlarged view of the region E2 which is a part thereof. The image C2 is a pattern image in which a foreground portion C2a and a background portion C2b are expressed in binary, as shown in an area E2.
For example, the foreground portion C2a is printed with a halftone dot area ratio of 100%, and the background portion C2b is printed with a halftone dot area ratio of 25%, for example. However, this ratio is also an example and is not limited to this. For example, the halftone dot area ratio of the foreground portion C2a may be less than 100%. The rate may be greater than or equal to 25% or less. Also, the density of the foreground portion C2a and the background portion C2b may be reversed.
The density difference between the foreground portion C2a and the background portion C2b is greater than the density difference between the foreground portion C1a and the background portion C1b.

Here, the pattern images of the bright layer 31 and the transparent layer 32 of the information recording medium 30 are not limited to printed pattern images each having a foreground portion and a background portion.
FIGS. 4A and 4B show the case where the image Cx of the bright layer 31 and the image Cy of the transparent layer 32 are pattern images consisting only of the foreground portion. In this case, the print regions Cxa and Cya of the image Cx and the image Cy are printed at a halftone dot area ratio of 100%, and the pattern image is expressed in binary by the print regions Cxa and Cya and the non-printing regions Cxb and Cyb. become a thing.

In the information recording medium 30 described above, the recognizable image changes depending on the viewing angle (observation angle).
FIG. 5 is a diagram for explaining an observation mode based on the structure of the information recording medium 30 according to this embodiment.

FIG. 5A shows three positional relationships among the illumination light source L in the diffuse reflection area and the regular reflection (specular reflection) area, the viewpoint E (Ea to Ec), and the information recording medium 30. .
When the viewpoint E (Ea) is at the position P1 with respect to the positions of the illumination light source L and the information recording medium 30 as shown in FIG. This is the case where the illumination light source L is illuminating the surface of the information recording medium 30 from an oblique direction, and the position P1 at this time is the normal direction (Z direction) of the information recording medium 30, This is the position facing the information recording medium 30 . Also, when the illumination light source L and the information recording medium 30 are under the same conditions and the viewpoint E (Eb) is at the position P2, the observation is made in the specular reflection area at the position P2. In this case, the position P2 is a position symmetrical to the illumination light source L with respect to the normal to the information recording medium 30, where the angle between the normal to the information recording medium 30 and the illumination light source L is an angle θL, This is the position where the information recording medium 30 is viewed from the direction of the angle θR, which is the same angle as the angle θL.

Here, the illumination light source L outputs visible light.
When the viewpoint E (Ec) is at a position P3 with respect to the positions of the illumination light source L and the information recording medium 30 as shown in FIG. , the illumination light source L and the position P3 are at line-symmetrical positions. Therefore, in this case as well, the observation is made in the specular reflection area at the position P3.
The image C1 and the image C2 shown in FIG. 3 will be described below as an example.

When the information recording medium 30 is composed of only the bright layer 31, in the diffuse reflection area, a large difference in the amount of reflected light occurs due to the density difference between the foreground portion C1a and the background portion C1b of the image C1 in FIG. 3A. , the foreground portion C1a and the background portion C1b can be distinguished. On the other hand, in the specular reflection area, both the foreground portion C1a and the background portion C1b reflect large amounts of light, so that the difference cannot be perceived and the foreground portion C1a and the background portion C1b cannot be distinguished.

Next, when the information recording medium 30 consists of only the transparent layer 32, the foreground portion C2a and the background portion C2b in FIG. 3B are transparent and cannot be distinguished from each other in the diffuse reflection area. On the other hand, in the specular reflection area, since the amount of reflected light varies depending on the density difference between the foreground portion C2a and the background portion C2b, the foreground portion C2a and the background portion C2b can be distinguished.
When the information recording medium 30 has the transparent layer 32 formed on the bright layer 31, the foreground portion C1a and the background portion C1b can be distinguished from each other in the diffuse reflection area. Since C2b cannot be distinguished, the foreground portion C1a and the background portion C1b are observed as a whole. In the specular reflection area, the foreground portion C1a and the background portion C1b cannot be distinguished, but the foreground portion C2a and the background portion C2b can be distinguished, and the foreground portion C2a and the background portion C2b are observed as a whole.

In this way, the bright layer 31 and the transparent layer 32 are made of a material (such as ink) that reflects light in different amounts depending on the viewing angle. It can be displayed in various ways, such as visible or invisible.
Using this principle, the information recording medium 30 is photographed by the reading device 5, and an image of only the transparent layer 32 or the bright layer 31 is acquired, thereby using the information recording medium 30 for authenticity determination.

<Reproduction of printed matter 1>
Next, in order to show that the information recording medium 30 is used for authenticity determination, a case where the printed matter 1 is duplicated will be described.
FIG. 6 is a diagram for explaining the positional relationship between the illumination light source L and the camera C when copying the printed matter 1 according to this embodiment.
The image of the information recording medium 30 of the printed matter 1 is captured by the camera C while the information recording medium 30 is irradiated with light from the illumination light source L shown in FIG.

FIG. 6 shows a case where the illumination light source L irradiates the information recording medium 30 from a slightly oblique direction, and the camera C photographs the information recording medium 30 from a vertical direction to obtain an image. When the illumination light source L, the camera C, and the printed material 1 are in a positional relationship as shown in FIG. Secondly, the camera C reads the light diffusely reflected by the surface of the printed matter 1 . Therefore, the camera C captures images of both the bright layer 31 and the transparent layer 32 of the information recording medium 30 depending on the positional relationship between the illumination light source L and the information recording medium 30 .
Based on the image obtained by the camera C in this manner, a copy of the printed matter 1 is produced in the copier.

Then, the copy product has a printed body on which the information recording body 30 is printed at a position corresponding to the information recording body 30 (see FIG. 1A) of the printed matter 1 . The printed body has a composite image of the pattern image of the bright layer 31 of the information recording body 30 and the pattern image of the transparent layer 32 . The printed body also has a layer of, for example, black ink containing carbon in general, or colored ink in the case of a color copy. Therefore, even when the printed material is observed at an observation angle from any area (diffuse reflection area, specular reflection area, etc.), only the composite image can be seen on the printed material. Therefore, only the pattern image of the transparent layer 32 cannot be observed on the printed material, and the printed material can be determined to be false when authenticity determination is performed.

Next, reading of the information recording medium 30 by the reading device 5 will be described.
FIG. 7 is a diagram showing the positional relationship between the out-camera 5C and the mobile light 5L of the reading device 5 that reads the information recording medium 30 according to this embodiment.
FIG. 8 is a diagram showing an example of reading patterns of the information recording medium 30 by the reading device 5 according to this embodiment.
FIG. 9 is a diagram showing a specific example of the reading pattern of the information recording medium 30 by the reading device 5 according to this embodiment.

The reading device 5 shown in FIG. 7 is, for example, a mobile terminal represented by a smart phone. In the example described in the present embodiment, the information recording medium 30 is read at each location (warehouse, during transportation, at a store, etc.) using the reading device 5 for checking the article to which the printed matter 1 is pasted from the time of manufacture to distribution. to read. Therefore, the reading device 5 is not a dedicated device but a mobile terminal owned by the user. The reading device 5 can be used for authenticity determination by installing a processing program 61a, which will be described later.
An out-camera 5C (reading unit) and a mobile light 5L (light-emitting unit) are provided at positions close to each other on the rear surface of the housing of the reading device 5 . A touch panel display 67, which will be described later, is provided on the front surface of the housing opposite to the side having the out-camera 5C and the mobile light 5L.

8A shows the layer structure of the information recording medium 30. FIG. Although the layer structure of the information recording medium 30 is illustrated in FIG. 1B, the information recording medium 30 in FIG. 2 is actually as shown in FIG. It becomes a layered structure of the state.

When obtaining an image of the bright layer 31 of the information recording medium 30, the user operating the reading device 5 photographs the information recording medium 30 using the out-camera 5C without turning on the mobile light 5L. At this time, the out-camera 5C is positioned at the viewpoint Ea in the positional relationship between the illumination light source L and the information recording medium 30 in FIG. 5(A). The illumination light source L in this case is ambient external light. As a result, as shown in FIG. 8B, the reading device 5 can acquire an image of the pattern 41 of only the image C1 of the bright layer 31 .

When obtaining an image of the transparent layer 32 of the information recording medium 30, the user operating the reading device 5 photographs the information recording medium 30 using the out-camera 5C while the mobile light 5L is turned on. At this time, the out-camera 5C is positioned at the viewpoint Ec in the positional relationship between the illumination light source L and the information recording medium 30 in FIG. 5B. As described above, theoretically, an image of the pattern 42 of only the image C2 of the transparent layer 32 can be obtained as shown in FIG. 8(C). However, in practice, the reading device 5 acquires an image including black noise 44 and white noise 45 in addition to the pattern 42 of only the image C2 of the transparent layer 32, as shown in FIG. 8(D). Here, the black noise 44 is a portion that is not originally obtained as a pattern, but is reflected black under the influence of the bright layer 31 . In addition, the white noise 45 is a portion that is originally obtained as a pattern, but is affected by the bright layer 31 and appears whiter than the bright layer 31 as a background.

An image obtained by photographing the information recording medium 30 using the out-camera 5C with the mobile light 5L of the reading device 5 turned on will be described with a more specific example.
FIG. 9A shows an image 48 in which an image showing a finder pattern (mark) by the transparent layer 32 is superimposed on the high-density pattern image by the bright layer 31 .
On the other hand, FIG. 9B shows an image 49 in which the image of the finder pattern of the transparent layer 32 is superimposed on the pattern image of the bright layer 31 having a low density.

White noise 45 and black noise 44 are more likely to occur in image 49 than in image 48 . Therefore, considering only the reading of the image of the transparent layer 32, it is preferable to form the image of the transparent layer 32 on the pattern image of the bright layer 31 with high density. However, when the image of the transparent layer 32 is formed on the high-density pattern image of the bright layer 31, the visual visibility of the image of the transparent layer 32 is improved, and the image of the transparent layer 32 may appear at first glance. is more likely to be recognized.
Therefore, in the present embodiment, the black noise 44 and the white noise 45 are processed by the reading device 5 to convert the pattern 42 of only the image C2 of the transparent layer 32 shown in FIG. 8C.

<Reading device 5>
Next, the reading device 5 for reading the code from the information recording medium 30 of the printed matter 1 will be described.
FIG. 10 is a functional block diagram of the reader 5 according to this embodiment.
The reading device 5 includes a control unit 50 , a storage unit 60 , an out-camera 5C, a mobile light 5L, a touch panel display 67 (display unit), and a communication interface unit 69 .

The control unit 50 is a CPU (central processing unit) that controls the entire reading device 5 . The control unit 50 cooperates with the hardware described above and executes various functions by appropriately reading and executing an OS (operating system) and application programs stored in the storage unit 60 .
The control unit 50 includes a light control unit 51, an image reception unit 52 (reading means), a code area acquisition unit 53 (code area acquisition means), a code identification unit 54 (code identification means), and an information acquisition unit 55 ( information acquisition means, authenticity determination means) and an information output section 56 (information output means).

In response to the activation of the processing program 61a, the light control unit 51 causes the mobile light 5L to irradiate the light, thereby continuing the light output. The light control section 51 may stop the output of the light emitted from the mobile light 5L when the image data of the information recording medium 30 is received by the image receiving section 52 described below.
Image reception unit 52 receives image data of information recording medium 30 via out camera 5C by facing out-camera 5C to information recording medium 30 and reading information recording medium 30 with out-camera 5C.

The code area acquisition unit 53 detects an identification area from image data and acquires a code area (reading area) based on the detected identification area. Here, the identification area may be an outer frame of the two-dimensional code (see FIG. 2), or may be a finder pattern (to be described later) or the like, which can be used to detect the code area.
The code identification unit 54 performs image processing on the code area to identify the code. Here, the code identification unit 54 divides the code area into cells and identifies the code by performing binarization processing using the luminance value of each cell. Further, the binarization process is a process of changing the luminance value of one cell using the average value of the luminance value of the one cell and the luminance values of the cells located in the vicinity of the one cell. In the binarization, a threshold value is used for the luminance value of each cell after the change to make it black or white.

The information acquisition unit 55 performs predetermined conversion on the code specified by the code specification unit 54 and acquires variable information.
Information output unit 56 outputs information based on the variable information acquired by information acquisition unit 55 to touch panel display 67 .

The storage unit 60 is a storage area such as a semiconductor memory device for storing programs, data, etc. necessary for the control unit 50 to execute various processes.
A computer is an information processing apparatus having a control unit, a storage device, etc. The reading device 5 is an information processing apparatus having a control unit 50, a storage unit 60, etc., and is included in the concept of a computer.

Storage unit 60 stores program storage unit 61 .
The program storage unit 61 is a storage area that stores various programs. The program storage unit 61 stores a processing program 61a (program). The processing program 61 a is a program for executing each function of the control section 50 .

The touch panel display 67 has a function as a display section configured by a liquid crystal panel or the like and a function as an input section for detecting touch input by a user's finger or the like.
The communication interface unit 69 is an interface for communicating with an external server or the like.

<Processing of reading device 5>
Next, processing of the reading device 5 will be described.
FIG. 11 is a flowchart showing reading processing in the reading device 5 according to this embodiment.
FIG. 12 is a flowchart showing code identification processing in the reading device 5 according to this embodiment.
FIG. 13 is a diagram for explaining code identification processing in the reading device 5 according to this embodiment.
14 and 15 are diagrams for explaining the binarization processing in the reading device 5 according to this embodiment.

First, when the user operates the reading device 5 to start the processing program 61a, the control section 50 of the reading device 5 starts reading processing shown in FIG.
In step S (hereinafter, "step S" is simply referred to as "S") 11 in FIG. 11, the control unit 50 of the reading device 5 activates the out-camera 5C.
In S12, the control unit 50 (light control unit 51) causes the mobile light 5L to emit light.

In this reading process, since it is desired to determine the authenticity of the information recording medium 30, the user specifies a specular reflection area where only the second image of the transparent layer 32 used for authenticity determination of the information recording medium 30 can be visually recognized, and reads the image. Do an operation to read. To specify the specular reflection area, for example, the user may position the reading device 5 so as to face the information recording medium 30 in the normal direction of the information recording medium 30 . With this configuration, the positional relationship between the mobile light 5L of the reading device 5 and the out-camera 5C becomes the same as the relationship between the illumination light source L and the position P3 in FIG. The second image of the transparent layer 32 of the information recording medium 30 can be read.

In S13, the control unit 50 determines whether or not a shooting operation has been accepted. The control unit 50 causes the touch panel display 67 to display, for example, a shutter button (not shown). Then, upon accepting the selection of the shutter button by the user, the control unit 50 determines that the shooting operation has been accepted. If the shooting operation has been accepted (S13: YES), the control unit 50 shifts the process to S14. On the other hand, if the photographing operation has not been accepted (S13: NO), the control unit 50 remains in this process until the photographing operation is accepted.
In S14, the control unit 50 (image accepting unit 52) accepts image data captured via the out-camera 5C.
In the processing of S13 and S14, the photographing by the photographing operation has been described, but the control unit 50 may automatically photograph.
In S15, the control unit 50 performs code identification processing for identifying the code from the image data.

Here, the code identification processing will be described with reference to FIG. 12 .
In S21 of FIG. 12, the control unit 50 (code area acquisition unit 53) detects an identification area included in the image data.
FIG. 13A shows a photographed image 70 with lines for dividing each cell. Also, FIG. 13B shows an image 71 in which the identification area 71a is detected.

In S22 of FIG. 12, the control unit 50 (code region acquisition unit 53) acquires the code region based on the detected identification region.
FIG. 13(C) shows an image 72 of only the code region based on the identification region 71a detected from the image 71 of FIG. 13(B). The control unit 50 can acquire an image 72 of only the code area by deleting the identification area 71a and the inner width of the identification area 71a.

In S23 of FIG. 12, the control unit 50 (code specifying unit 54) divides the code region into cells.
FIG. 13(D) shows an image 73 obtained by dividing the image 72 of FIG. 13(C) into cells.
In S24 of FIG. 12, the control unit 50 (code specifying unit 54) performs binarization processing for each cell using the luminance value of each cell.
FIG. 13(E) shows an image 74 obtained by averaging the image 73 of FIG. 13(D) using the luminance value of each cell, and FIG. An image 75 after the value conversion process is shown.

Here, the binarization processing will be described with reference to FIGS. 14 and 15. FIG.
In FIG. 14, the control unit 50 classifies each cell in the image 73 shown in FIG. 13(D). Next, the control unit 50 acquires the average value for each category, and uses the acquired average value as the brightness value of each cell belonging to the category. For example, in a small image 81 including a cell 81a and its surrounding cells, a small image 91 in which the noise (black noise and white noise) of each cell is absorbed can be acquired. The control unit 50 can obtain the image 74 of FIG. 13(E) by performing this process on each cell included in the image 73 (FIG. 13(D)).

The image of the code area transitions like a gradation between a bright area and a dark area depending on the position of the mobile light 5L. In addition, the mobile light 5L is a low light source, and the brightness of the light source is gradually attenuated as the light continues to be emitted, so the difference between the bright area and the dark area gradually occurs. Therefore, if the same threshold value is used throughout the binarization, there is a problem that the noise portion cannot be determined correctly. Therefore, as the binarization process, a process of setting a threshold based on the average of the peripheral luminance values for each cell and making a determination is performed for each cell.
FIG. 15 shows an example of processing. The image 74 includes a small image 91 contained in the bright area Ra and a small image 92 contained in the dark area Rb. Here, FIG. 15 shows the luminance value of each cell in the small images 91 and 92 .

Here, the process of converting to binary will be described using the small image 91 as an example. The average luminance value of all the cells included in the small image 91 is 144. Also, the luminance value of the cell 91a, which is the target cell, is 125. Since the luminance value (125) of the cell 91a is lower than the average luminance value (144), the controller 50 determines that the cell 91a is a black cell.
Next, in the small image 92, the average luminance value of all the cells included in the small image 92 is 78. Also, the luminance value of the cell 92a, which is the target cell, is 90. Since the luminance value (90) of the cell 92a is higher than the average luminance value (78), the controller 50 determines that the cell 92a is a white cell.
In the above example, since the cells 91a and 92a are not located around the image 74, there are eight peripheral cells, and the average luminance value is the sum of the self cell and the eight peripheral cells. is the average value of 9 cells. If the cells are around the image 74, there may be five or three peripheral cells.

In this way, if the process of setting a threshold based on the average of the peripheral luminance values for each cell and making a determination is performed for each cell, even if the image 74 has a bright region Ra and a dark region Rb, the surrounding Binarization can be performed using the average brightness value of the cell, and correct determination can be made.

After the control unit 50 performs the code identification processing, in S16 of FIG. 11, the control unit 50 (information acquisition unit 55) performs predetermined conversion processing on the code identified in the processing of S15 to acquire variable information. do. Here, if the code can be correctly specified by the process of S15, variable information can be obtained by a predetermined conversion process. On the other hand, if the code cannot be specified correctly by the process of S15, or if the image of an illegal printed matter such as a duplicate is read and processed, the variable information cannot be obtained by the predetermined conversion process.

In S17, the control unit 50 (information acquisition unit 55) determines whether variable information has been acquired. If the variable information has been acquired (S17: YES), the control unit 50 shifts the process to S18. On the other hand, if the variable information could not be acquired (S17: NO), the control unit 50 moves the process to S19.

In S<b>18 , the control unit 50 (information output unit 56 ) outputs information based on the variable information to the touch panel display 67 . Here, the information based on the variable information may be, for example, a serial number unique to the information recording medium 30 or a message such as "This is a genuine product." After that, the control unit 50 terminates this process.
On the other hand, in S<b>19 , the control unit 50 outputs a read error to the touch panel display 67 . It should be noted that the output may be a counterfeit message instead of a reading error message. After that, the control unit 50 terminates this process.

Thus, according to this embodiment, the following effects are obtained.
(1) Since the information recording medium 30 includes the image B1, which is a solid image, in the bright layer 31, and the outer frame of the two-dimensional code of the transparent layer 32 is superimposed on the image B1, the code area can be reliably read. be able to.
(2) Since the image on the bright layer 31 is microcharacters and the two-dimensional code is formed on the microcharacters, the two-dimensional code can be made difficult to recognize visually.
Further, by forming the two-dimensional code on the transparent layer 32 with a pattern image, it is possible to make it more difficult to visually recognize the two-dimensional code.

(3) The information recording medium 30 uses the two-dimensional code and the outer frame of the code as the second image, so that the code area of the two-dimensional code can be grasped by recognizing the outer frame. As a result, the code area can be reliably read.

(4) In the information recording medium 30, the glitter layer 31 is made of a glitter material, so the transparent layer 32 can be more visible depending on the viewing angle.
(5) Since the printed matter 1 having the information recording medium 30 can be attached to various articles, the information recording medium 30 can be used for brand protection by reading codes.

(6) The reader 5 outputs light to read the information recording medium 30 at an observation angle where only the transparent layer 32 can be seen, detects the identification area from the read image, and acquires the code area based on the detected identification area. Then, image processing is performed on the obtained code area to identify the code. Therefore, the code region can be obtained more reliably than the identification region. Also, the code can be identified by image processing.

(7) The reading device 5 divides the code area into cells and performs binarization processing using the luminance value of each cell to specify the code. Makes code easier to identify.
In the binarization process, the luminance value of one cell is changed by using the average value of the luminance values of the cells of the same classification, so the luminance values of the cells of the same classification as the cell to be processed are leveled. can.
Furthermore, in the binarization process, the target cell is binarized using the average luminance value of the surrounding cells. can be valuated.

(8) The reading device 5 acquires variable information from the specified code, and outputs information based on the acquired variable information to the touch panel display 67 . Therefore, for example, the authenticity determination result can be output to the touch panel display 67 .

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. Moreover, the effects described in the embodiments are merely enumerations of the most suitable effects produced by the present invention, and the effects of the present invention are not limited to those described in the embodiments. The above-described embodiments and modifications described later can be used in combination as appropriate, but detailed description thereof will be omitted.

(deformed form)
(1) In the present embodiment, the peripheral frame is used as an identification area, but the identification area is not limited to this. For example, it may be a mark indicating the existence of the code, and in the case of a two-dimensional code, the mark may be a finder pattern.
FIG. 16 is a diagram showing an example of an image of an information recording medium according to a modification.
FIG. 17 is a diagram for explaining binarization processing in the reading device according to the modification.
In FIG. 16(A), the image C1 and the image B1 of the bright layer 31-2 and the image C2 of the transparent layer 32-2 are superimposed to form the information recording medium 30-2 of FIG. 16(B). indicates Here, the finder pattern of the transparent layer 32 is formed over the image B1.
With this information recording medium 30-2, when the reader 5 reads the transparent layer 32-2 of the information recording medium 30-2, the finder pattern can be reliably read, so that the code area can be easily specified. can be done.

Further, as shown in FIG. 17, if the finder pattern is stored in advance in the storage unit 60 in the binarization process by the reading device 5, the image 174 can be converted to the finder pattern part like the image 174-2. Binary processing can be done by deciding. By doing so, the code identification process can be made easier.

(2) In the present embodiment, an example of printing a pattern image has been described, but the present invention is not limited to this. A pattern image may be formed by a method other than printing such as transfer or laser drawing.
(3) In the present embodiment, a label is used as an example of a printed material having an information recording medium, but the present invention is not limited to this. For example, a ticket used to enter an entertainment facility or a card used in a game may be used as long as the medium has an information recording medium. Also, the information recording medium may be used for electronic watermarking. Further, the medium is not limited to a medium having an information recording medium, and may be a booklet having an information recording medium.
(4) In the present embodiment, the bright layer 31 and the transparent layer 32 are assumed to be square, but they are not limited to this. For example, the bright layer 31 may have other shapes such as a rectangular shape, a circular shape, and an elliptical shape. Also, the transparent layer 32 may have a rectangular shape in the case of a bar code, for example, depending on the shape of the code.

(5) In the present embodiment, an example in which the transparent layer 32 is formed directly on the bright layer 31 has been described, but the present invention is not limited to this. For example, a substrate such as a transparent film may be provided between the bright layer 31 and the transparent layer 32 . Further, for example, in contrast to the case where the transparent layer 32 is formed on the bright layer 31 described in the present embodiment, even if the transparent layer 32 further has a substrate such as a transparent film, good. By having a substrate such as a transparent film in this way, the part of the bright layer 31, which is the layer below the transparent film, is less likely to be scraped off.

(6) In the present embodiment, the image of the bright layer 31 is a pattern image such as that shown in FIG. 3 and microcharacters such as those shown in FIG. 2 are formed. However, the present invention is not limited to this. For example, only the pattern image as illustrated in FIG. 3 may be used. By doing so, the image of the glittering layer 31 can be rendered meaningless at first glance by a person due to the pattern image.
(7) In the present embodiment, the image C2 of the transparent layer 32 is read as the processing by the reading device, and the code is specified to determine the authenticity, for example, but the present invention is not limited to this. For example, if the bright layer 31 also contains a code and the code on the bright layer 31 can also be read, it may be determined to be true by authenticity determination. Further, authenticity determination may be performed depending on whether or not the combination of the code of the bright layer 31 and the code of the transparent layer 32 is stored in an authenticity determination table (not shown) stored in the storage unit of the reading device.

(8) In the present embodiment, an example in which the transparent layer forms a code with a pattern image has been described, but the present invention is not limited to this. The transparent layer may form a code with a solid image.

1 printed matter 5 reader 5C out camera 5L mobile light 10 base 11 substrate layer 12 adhesive layer 13 peelable support layer 30, 30-2 information recording medium 31, 31-2 bright layer 32, 32-2 transparent layer 41, 42 pattern 44 black noise 45 white noise 50 control unit 51 light control unit 52 image reception unit 53 code area acquisition unit 54 code identification unit 55 information acquisition unit 56 information output unit 60 storage unit 61a processing program 67 touch panel display B1, C1, C2 Image C Camera L Light source

Claims (16)

An information recording medium comprising a first ink layer and a second ink layer,
The first ink layer and the second ink layer are
Provided on one surface of the substrate,
Each is configured so that the amount of reflected light varies depending on the observation angle,
The first ink layer is a first image including a solid image,
the second ink layer is a second image formed of a transparent material and containing a code with variable information;
An information recording medium, wherein an identification area for recognizing a reading area of the code in the second image is formed on the solid image. In the information recording medium according to claim 1,
the first image further includes a pattern image;
An information recording medium, wherein at least part of the second image is formed over the pattern image. In the information recording medium according to claim 1 or claim 2,
The information recording medium, wherein the second image includes a pattern image. In the information recording medium according to any one of claims 1 to 3,
The code is a two-dimensional code,
The information recording medium, wherein the identification area of the code is an outer peripheral frame of the code. In the information recording medium according to any one of claims 1 to 3,
The code is a two-dimensional code,
The information recording medium, wherein the identification area of the code is a mark indicating existence of the code. In the information recording medium according to any one of claims 1 to 5,
The information recording medium, wherein the first image includes an image of a code different from the second image. In the information recording medium according to any one of claims 1 to 6,
The information recording medium, wherein the first ink layer is formed of a glitter material. A label comprising the information recording medium according to any one of claims 1 to 7. A reader for reading the information recording medium according to any one of claims 1 to 7,
a reading unit;
a light emitting unit that is provided near the reading unit and emits light;
reading means for reading an image including the second image of the information recording medium while the reading section is irradiated with light from the light emitting section;
a code area obtaining means for detecting the identification area from the image read by the reading means and obtaining a code area based on the detected identification area;
code identification means for performing image processing on the code area acquired by the code area acquisition means to identify the code;
A reader comprising: A reader according to claim 9, comprising:
The code identifying means divides the code area into cells, performs a binarization process using a luminance value of each cell, and identifies the code. A reader according to claim 10, comprising:
In the reading device, the binarization process obtains an average value for each classification based on the luminance value of each cell, and uses the obtained average value as the luminance value of each cell belonging to the classification. The reading device according to claim 10 or 11,
The reading device, wherein the binarization process binarizes the one cell using an average value of the luminance value of the one cell and the luminance values of the cells located in the vicinity of the one cell. The reader according to any one of claims 9 to 12,
The code identifying means, when the detected identification area has a shape stored in advance, performs a binarization process corresponding to the shape. The reader according to any one of claims 9 to 13,
information obtaining means for obtaining the variable information from the code identified by the code identifying means;
information output means for outputting information based on the variable information acquired by the information acquisition means to a display;
A reader. A program to be executed by a computer for determining the authenticity of the information recording medium according to any one of claims 1 to 7,
said computer,
reading means for reading an image including the second image on the information recording medium;
code area acquisition means for detecting the identification area from the read image and acquiring a code area based on the detected identification area;
code identifying means for performing image processing on the obtained code region to identify the code;
information acquisition means for acquiring the variable information from the specified code;
authenticity determination means for determining that the information recording medium is true when the variable information can be acquired;
program to function as A method for determining authenticity of an information recording medium according to any one of claims 1 to 7,
the computer
reading an image including the second image on the information recording medium;
detecting the identification region from the read image and obtaining a code region based on the detected identification region;
performing image processing on the obtained code region to identify the code;
obtaining the variable information from the identified code;
determining that the information recording body is true when the variable information can be acquired;
Authenticity determination method including.

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