JP7172439B2 - Printed matter, decoding method, decoding device, and decoding system - Google Patents

Description

The present invention relates to printed matter, a decoding method, a decoding device, and a decoding system.

It is sometimes desired that the information recorded on printed matter is identifiable only when necessary.

For example, Patent Literature 1 describes providing a concealing layer that can be scraped off by scratching so that information recorded on the card cannot be easily identified. Patent Literature 2 describes that a code pattern including data representing characteristics unique to a game character is printed on a card used in a card game machine so as to be identifiable by infrared rays. Patent Document 3 describes partially increasing or decreasing the brightness of an original image, thereby embedding a two-dimensional code in the original image. In Patent Document 4, a line-shaped uneven structure that is parallel to the previous lines and has a different pitch from the previous lines is provided so as to partially overlap the lines printed with colored ink. It is described that the overlapped portion is used as a latent image.

JP-A-2002-36740 WO2010/095379 JP 2011-142607 A JP 2006-111019 A

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing technology that makes it difficult for a person who does not know how to read information to read information.

According to the first aspect of the present invention, it comprises a substrate and one or more printed layers provided on the substrate, wherein the one or more printed layers are made of the same material and have a plurality of patterns adjacent to each other. wherein each of the plurality of patterns comprises a plurality of sub-patterns arranged in two directions and having shapes equal to each other; a first array consisting of one or more of the plurality of patterns, wherein the plurality of sub-patterns are different and occupy the same area ratio in a unit area; A second array consisting of a printed matter constituting a background of said one-dimensional or two-dimensional code is provided.

It should be noted that "the area ratios of a plurality of subpatterns occupying a unit region are equal to each other" means that the difference in the area ratios is sufficient to make the plurality of patterns indistinguishable from each other when observed with the naked eye by humans. means less than . That is, when the area ratio is different between two or more patterns, the difference between the _{maximum area ratio Rmax and the minimum area ratio Rmin, Rmax-Rmin , and the} maximum area ratio _Rmax If the ratio of (R _max −R _min )/R _max is sufficiently small, eg, less than or equal to 0.1%, the patterns cannot be distinguished from each other by visual observation.

In addition, "the shape of the sub-pattern is different" means that one or more of the shape of the contour of the sub-pattern, the size of the sub-pattern, and the thickness of the lines forming the sub-pattern are different. there is

According to the second aspect of the present invention, from the image obtained by imaging the area corresponding to the plurality of patterns in the printed matter according to the first aspect, based on the shapes of the plurality of sub-patterns, the one-dimensional Alternatively, a decoding method is provided that includes decoding a two-dimensional code.

According to the third aspect of the present invention, a plurality of patterns having different image densities are generated from the images of the plurality of patterns obtained by photographing the printed matter according to the first aspect; decoding the one-dimensional or two-dimensional code from the pattern of

According to the fourth aspect of the present invention, based on the shapes of the plurality of sub-patterns, from the first image data obtained by imaging the regions corresponding to the plurality of patterns in the printed matter according to the first aspect, A decoding device is provided that includes a processing unit that decodes the one-dimensional or two-dimensional code.

According to the fifth aspect of the present invention, from the first image data including the plurality of pattern information obtained by photographing the printed material according to the first aspect, the second image data including the plurality of pattern information having different image densities is obtained. A decoding device is provided that includes a processing unit that generates image data and decodes the one-dimensional or two-dimensional code from the second image data.

According to a sixth aspect of the present invention, the decoding device according to the fourth or fifth aspect, a reading unit that captures the printed matter and acquires the first image data, the decoded one-dimensional or two-dimensional code, A decoding system is provided that includes original information obtained by decoding a one-dimensional or two-dimensional code, and an output unit that outputs one or more pieces of information generated using the original information.

According to the present invention, a printing technique is provided that makes it difficult for people who do not know how to read information to read it.

1 is a plan view schematically showing a printed matter according to a first embodiment of the invention; FIG. FIG. 2 is a plan view showing an enlarged part of the printed matter of FIG. 1; FIG. 3 is a cross-sectional view along line III-III of the structure shown in FIG. 2; FIG. 3 is an enlarged plan view showing a first pattern of the printed matter shown in FIGS. 1 and 2; FIG. 5 is an enlarged plan view showing a first sub-pattern forming the first pattern shown in FIG. 4; The top view which expands and shows the 2nd pattern of the printed matter shown in FIG.1 and FIG.2. FIG. 7 is an enlarged plan view showing a second sub-pattern forming the second pattern shown in FIG. 6; The top view which expands and shows the 3rd pattern of printed matter shown in FIG.1 and FIG.2. FIG. 9 is an enlarged plan view showing a third sub-pattern forming the third pattern shown in FIG. 8; 1 is a block diagram that schematically illustrates a decoding system according to an embodiment of the invention; FIG. 4 is a flowchart showing a decoding method according to a modification; FIG. 4 is a diagram schematically showing an example of a method of adjusting resolution; FIG. 4 is a diagram schematically showing an example of an image of a first sub-pattern with reduced resolution; FIG. 11 is a diagram schematically showing an example of an image of a second sub-pattern with reduced resolution; FIG. 11 is a diagram schematically showing an example of an image of a third sub-pattern with reduced resolution; The figure which shows an example of the decoded two-dimensional code. FIG. 4 is a plan view schematically showing a printed matter according to a first comparative example; FIG. 18 is a cross-sectional view along line XVIII-XVIII of the printed matter shown in FIG. 17; FIG. 10 is a plan view schematically showing a printed matter according to a second comparative example; FIG. 20 is a cross-sectional view along line XX-XX of the printed matter shown in FIG. 19; The top view which shows roughly the printed matter which concerns on a 3rd comparative example. FIG. 22 is a cross-sectional view along line XXII-XXII of the printed matter shown in FIG. 21; The top view which expands and shows a part of printed matter which concerns on 2nd Embodiment of this invention. The top view which expands and shows a part of printed matter which concerns on 3rd Embodiment of this invention. A plan view schematically showing a modified example of the first pattern. A plan view schematically showing a modified example of the second pattern. A plan view schematically showing a modified example of the third pattern.

Embodiments of the present invention will be described below with reference to the drawings. Elements having the same or similar functions are denoted by the same reference numerals, and overlapping descriptions are omitted.

First, a first embodiment of the present invention will be described.
FIG. 1 is a plan view schematically showing a printed matter according to the first embodiment of the invention. 2 is a plan view showing an enlarged part of the printed matter of FIG. 1. FIG. FIG. 3 is a cross-sectional view of the structure shown in FIG. 2 along line III-III.

In the figure, the X direction is the direction parallel to the printing surface of the printed matter 1, the Y direction is the direction parallel to the printing surface of the printed matter 1 and perpendicular to the X direction, and the Z direction is the X direction. and perpendicular to the Y direction. In the plan view referred to in the description of the printed matter 1, the protective layer 13, which will be described later, is omitted.

The printed matter 1 shown in FIGS. 1 to 3 is a card. The printed matter may have a shape other than a card. The printed matter 1 can be used, for example, as an identification card, a game card, or securities. The printed matter 1 may be a label to be supported by another article. For example, printed matter 1 may be a self-adhesive label. That is, the printed product 1 may be used in labeled articles.

This printed matter 1 includes a substrate 11, a printed layer 12, and a protective layer 13, as shown in FIG.

The base material 11 is made of paper, plastic, or metal, for example. The base material 11 may have a single layer structure or may have a multilayer structure. Here, the substrate 11 has a lamellar shape, but the substrate 11 may have other shapes. Also, the substrate 11 may further include other elements such as an IC (integrated circuit) chip, an antenna, and a magnetic tape.

The print layer 12, as shown in FIG. 1, includes a first portion P1, a second portion P2, and a third portion P3.

The first portion P1 includes a first pattern PT1, a second pattern PT2, and a third pattern PT3, as shown in FIG. Here, the first portion P1 includes three patterns, but the first portion P1 may include two or more patterns. The first portion P1 has substantially the same thickness throughout.

The first pattern PT1, the second pattern PT2 and the third pattern PT3 are made of the same material. That is, they are formed with the same ink. The ink may be ink used for normal printing, such as process ink, or special ink such as infrared absorbing ink and infrared emitting ink. As the infrared absorbing ink, for example, an ink containing a near-infrared absorbing agent such as a phthalocyanine compound and a cyanine compound can be used. As the infrared emitting ink, for example, an ink containing an infrared emitting phosphor that is excited by infrared rays and emits infrared rays having a longer wavelength than the excitation light can be used. The special ink may be colored ink or invisible ink, that is, colorless and transparent ink.

When viewed with the naked eye, the first portion P1 appears as a uniform area, ie, an area having the same color throughout. A two-dimensional code is recorded as a latent image in the first portion P1. The latent image recorded in the first portion P1 may be a one-dimensional code. The first portion P1 will be detailed later.

The second part P2 contains a pattern corresponding to the character string "1234567890", as shown in FIG. This pattern consists of key information for decoding the information recorded in the first portion P1, for example, a first pattern PT1, a second pattern PT2, and a third pattern PT3, which constitute a first array and a third pattern PT3. It is a pattern corresponding to the key information for distinguishing between the two arrays. The pattern corresponding to the key information may be another character string, a one-dimensional or two-dimensional code, or have other shapes.

The pattern included in the second portion P2 may be formed with a single ink, or may be formed with a plurality of types of ink. Moreover, the pattern included in the second portion P2 may be formed with the same ink as the ink forming the pattern of the first portion P1, and the ink forming the pattern of the first portion P1 is It may be formed with different inks.

The second portion P2 may be provided on the same substrate as the first portion P1, or may be provided on a different substrate. The second part P2 can be omitted.

The third part P3 contains a pattern corresponding to the string "ABCDEFGHIJKLMN". This pattern may be another character string, a photograph of a face, a drawing, a picture, or a combination thereof.

The pattern contained in the third portion P3 may contain information associated with at least one of the information recorded in the first portion P1 and the information recorded in the second portion P2. Alternatively, the information contained in this pattern may be independent of both the information recorded in the first portion P1 and the information recorded in the second portion P2. Alternatively, the pattern may not contain information, such as a simple pattern.

The pattern included in the third portion P3 may be formed with a single ink, or may be formed with a plurality of types of ink. Moreover, the pattern included in the third portion P3 may be formed with the same ink as the ink forming the pattern of the first portion P1 or the second portion P2. may be formed with an ink different from the ink forming the pattern.

The third portion P3 may be provided on the same substrate as the first portion P1 or the second portion P2, or may be provided on a different substrate. The third part P3 can be omitted.

The protective layer 13 covers the print layer 12 as shown in FIG. Protective layer 13 protects printing layer 12 from damage. The protective layer 13 may be provided so as to cover the entire main surface of the substrate 11 on which the printed layer 12 is provided, or may be provided so as to cover only a part thereof.

Protective layer 13 is, for example, a transparent layer. All or part of the protective layer 13 may not be transparent. For example, when the pattern included in the first portion P1 is formed of infrared absorbing ink, the portion of the protective layer 13 covering the first portion P1 is in the infrared region that the infrared absorbing ink absorbs. Any material that blocks visible light may be used as long as it allows light to pass therethrough. Further, when the pattern included in the first portion P1 is formed of infrared light-emitting ink, the portion of the protective layer 13 covering the first portion P1 is exposed to light such as ultraviolet light that excites the infrared light-emitting ink. Alternatively, it may block visible light as long as it transmits infrared light and light in the infrared region, particularly light emitted from infrared light-emitting ink.

The thickness of the protective layer 13 is preferably 500 μm or less, more preferably in the range of 10 to 100 μm. A thin protective layer 13 may not adequately protect the printed layer 12 from damage. A thick protective layer 13 can increase the manufacturing cost of the printed matter 1 .

Next, the first portion P1 will be described in detail.
FIG. 4 is a plan view showing an enlarged first pattern of the printed matter shown in FIGS. 1 and 2. FIG. 5 is a plan view showing an enlarged first sub-pattern forming the first pattern shown in FIG. 4. FIG. 6 is a plan view showing an enlarged second pattern of the printed material shown in FIGS. 1 and 2. FIG. 7 is a plan view showing an enlarged second sub-pattern forming the second pattern shown in FIG. 6. FIG. 8 is a plan view showing an enlarged third pattern of the printed matter shown in FIGS. 1 and 2. FIG. 9 is a plan view showing an enlarged third sub-pattern forming the third pattern shown in FIG. 8. FIG.

As shown in FIG. 2, the first pattern PT1, the second pattern PT2 and the third pattern PT3 are adjacent to each other. A first array consisting of the first pattern PT1 constitutes a two-dimensional code. A second array composed of the second pattern PT2 and the third pattern PT3 constitutes the background of the two-dimensional code.

The first pattern PT1 consists of a plurality of first sub-patterns SPT1, as shown in FIG. The first sub-patterns SPT1 are arranged in two directions. Here, the first sub-patterns SPT1 are arranged with the same period in the X direction and the Y direction. The first sub-pattern SPT1 has an annular shape, as shown in FIG.

The second pattern PT2 consists of a plurality of second sub-patterns SPT2, as shown in FIG. The second sub-patterns SPT2 are arranged in two directions. Here, the second sub-patterns SPT2 are arranged with the same period in the X direction and the Y direction.

As is clear from the comparison between FIG. 7 and FIG. 5, the second sub-pattern SPT2 is different in shape from the first sub-pattern SPT1. Specifically, as shown in FIG. 7, the second sub-pattern SPT2 has a structure in which two circular rings, one of which has a smaller outer diameter than the other inner diameter, are arranged concentrically. there is 5 and 7, of the two rings included in the second sub-pattern SPT2, the curve forming the ring with the smaller diameter is included in the first sub-pattern SPT1. The thickness is almost equal to that of the curved lines that make up the ring. Further, the curve forming the ring with the larger diameter of the two rings included in the second sub-pattern SPT2 is larger than the curve forming the ring included in the first sub-pattern SPT1. It is thinner than the curve forming the smaller diameter of the two rings included in the second sub-pattern SPT2. The two rings included in the second sub-pattern SPT2 are spaced apart from each other.

The third pattern PT3 consists of a plurality of third sub-patterns SPT3, as shown in FIG. The third sub-patterns SPT3 are arranged in two directions. Here, the third sub-patterns SPT3 are arranged with the same period in the X direction and the Y direction.

As is clear from the comparison between FIG. 9 and FIGS. 5 and 7, the third sub-pattern SPT3 is different in shape from the first sub-pattern SPT1 and the second sub-pattern SPT2. Specifically, in the third sub-pattern SPT3, as shown in FIG. 9, the outer diameter of one ring is smaller than the inner diameter of the other one ring, and the inner diameter of the other one ring is It has a structure in which three rings larger than the outer diameter of the other ring are arranged concentrically. 5 and 9, the curves forming each ring included in the third sub-pattern SPT3 are the same as the curves forming the ring included in the first sub-pattern SPT1. thinner than The three rings included in the third sub-pattern SPT3 are spaced apart from each other.

The first pattern PT1, the second pattern PT2, and the third pattern PT3 have the same sub-pattern area ratio in the unit area. That is, the first pattern PT1, the second pattern PT2, and the third pattern PT3 are adjusted in shape and arrangement of the sub-patterns so that the area ratios of the sub-patterns in the unit area are equal to each other. . Here, as an example, it is assumed that the first sub-pattern SPT1, the second sub-pattern SPT2, and the third sub-pattern SPT3 have the same area and the same arrangement period.

Also, the first sub-pattern SPT1, the second sub-pattern SPT2, and the third sub-pattern SPT3 are so small that they are impossible or difficult to distinguish from each other when observed with the naked eye. Each of the sub-patterns preferably has a maximum dimension in the range of 0.5 to 30 mm, more preferably in the range of 1 to 10 mm. Here, the "maximum dimension" means the maximum value of the dimension when the sub-pattern is observed from the Z direction.

The thickness of the lines forming the sub-pattern is preferably in the range of 50 to 1,000 μm, more preferably in the range of 100 to 500 μm. Thin lines are difficult to print. On the other hand, thickening lines with small sub-patterns can collapse the gaps between the lines.

When one sub-pattern is composed of a plurality of parts spaced apart from each other, the distance between the parts is preferably 30 μm or more, more preferably 50 μm or more. If this distance is short, the above parts may be connected. Also, if this distance is short, image analysis may not be able to distinguish these parts from each other. Note that this distance is, for example, 1000 μm or less.

The sub-patterns are preferably arranged at a density of 0.85 to 50 lpi (lines per inch), and more preferably at a density of 2.5 to 25 lpi. Note that the unit "lpi" is the number of sub-patterns arranged in a length of 2.54 cm. If this density is low, it may become difficult to accurately reproduce the shape of the pattern in image analysis. If the density is high, the distance between the sub-patterns will be short and it may be difficult to distinguish them from each other in image analysis.

Next, the decoding system will be explained.
FIG. 10 is a block diagram that schematically illustrates a decoding system according to one embodiment of the invention.

A decoding system 2 shown in FIG. 10 includes a decoding device 21 , a reading section 22 and an output section 23 .
The decoding device 21 includes a processing section 211 and a storage section 212 .

The processing unit 211 includes a central processing unit (CPU). The reading unit 22 and the output unit 23 are connected to the processing unit 211 .

The processing unit 211, for example, decodes the two-dimensional code from the first image data based on the shape of the sub-pattern. Here, the first image data is obtained by photographing the printed matter 1 and is image data including information of the first pattern PT1, the second pattern PT2 and the third pattern PT3.

Alternatively, the processing unit 211 generates second image data from the first image data and decodes the two-dimensional code from the second image data. Here, the second image data is image data including information of a plurality of patterns with different image densities.

The processing unit 211 further decodes the original information from this two-dimensional code. The processing unit 211 may generate other information from this original information. The processing unit 211 outputs to the output unit 23 the decoded two-dimensional code, the original information obtained by decoding the two-dimensional code, and one or more of the information generated using this original information. Details of the processing executed by the processing unit 211 will be described later.

The storage unit 212 is connected to the processing unit 211 . The storage unit 212 includes a nonvolatile memory that stores programs read by the processing unit 211, data supplied from the processing unit 211, and the like.

The reading unit 22 includes an illumination device and an imaging device.
The illumination device illuminates a region of the printed matter 1 corresponding to the first portion P1. The illumination device emits visible light when the ink forming the pattern of the first portion P1 is process ink. The illumination device emits ultraviolet light or infrared light when the ink forming the pattern of the first portion P1 is infrared light emitting ink. The illumination device emits infrared rays when the ink forming the pattern of the first portion P1 is infrared absorbing ink. If outdoor light or indoor light can be used as illumination light, the illumination device can be omitted.

The imaging device images an area corresponding to the first portion P1 of the printed matter 1 . If the ink forming the pattern of the first portion P1 is process ink, the imaging device is a digital camera that captures an image displayed by light in the visible range. If the ink forming the pattern of the first portion P1 is infrared emitting ink or infrared absorbing ink, the imaging device is a digital camera that captures an image displayed by light in the infrared region.

The reading unit 22 may further include a moving mechanism, such as an XY table, for moving the printed matter 1 relative to the illumination device and imaging device. The imaging device may acquire an image of the entire area corresponding to the first portion P1 of the printed matter 1 by one imaging, or may acquire the image by imaging a plurality of times. A moving mechanism can be used in the latter case.

The reading unit 22 outputs to the processing unit 211 the first image data obtained by imaging the area corresponding to the first part P1 of the printed matter 1 with the imaging device. The reading unit 22 may capture an image of the area corresponding to the second portion P2 of the printed matter 1 and output the acquired image data to the processing unit 211 .

The output unit 23 converts the information output by the processing unit 211 into a form perceivable by humans, such as an image, sound, vibration, light, or a combination thereof, and outputs the information. The output unit 23 is, for example, a display, buzzer, vibrator, lamp, or combination thereof.

Next, a decoding method using this decoding system 2 will be described.
In this decoding method, first, an imaging device images an area corresponding to the first portion P1 of the printed matter 1 while the illumination device illuminates the area corresponding to the first portion P1 of the printed matter 1 . Thus, the reading unit 22 acquires the first image data. The reading unit 22 outputs this first image data to the processing unit 211 . Further, the reading unit 22 captures an image of the area corresponding to the second portion P2 of the printed matter 1 and outputs the acquired image data to the processing unit 211 .

The processing unit 211 decrypts the key information from the image data obtained by imaging the area corresponding to the second part P2 and the information stored in the storage unit 212 . The key information is, for example, that the arrangement of the pattern consisting of the first sub-pattern SPT1 is the first arrangement constituting the two-dimensional code, and that the pattern consisting of the second sub-pattern SPT2 and the pattern consisting of the third sub-pattern SPT3. is the second array constituting the background of the two-dimensional code.

The processing unit 211 also decodes the two-dimensional code from the first image data based on the difference in shape between the first sub-pattern SPT1, the second sub-pattern SPT2 and the third sub-pattern SPT3. Specifically, the processing unit 211 performs pattern matching using data related to the shapes of the first sub-pattern SPT1, the second sub-pattern SPT2, and the third sub-pattern SPT3 stored in the storage unit 212. The position information of the first sub-pattern SPT1, the second sub-pattern SPT2 and the third sub-pattern SPT3 is acquired from the image data. Next, the processing unit 211 obtains the shapes and positions of the first pattern PT1, the second pattern PT2, and the third pattern PT3 from the position information, and uses the key information to form the first array forming the two-dimensional code. and a second array that constitutes the background of the two-dimensional code. Thus, the processing unit 211 decodes the two-dimensional code from the first image data.

After that, the processing unit 211 decodes the original information from the two-dimensional code. The processing unit 211 generates other information from this original information in some cases. The processing unit 211 outputs to the output unit 23 the decoded two-dimensional code, the original information obtained by decoding the two-dimensional code, and one or more of the information generated using this original information.

The output unit 23 converts the information output by the processing unit 211 into a form perceivable by humans, such as an image, sound, vibration, light, or a combination thereof, and outputs the information.

Next, a modification of the decoding method using this decoding system 2 will be described.
FIG. 11 is a flow chart showing a decoding method according to a modification. FIG. 12 is a diagram schematically showing an example of a method of adjusting resolution. FIG. 13 is a diagram schematically showing an example of an image of the first sub-pattern with reduced resolution. FIG. 14 is a diagram schematically showing an example of an image of the second sub-pattern with reduced resolution. FIG. 15 is a diagram schematically showing an example of an image of the third sub-pattern with reduced resolution.

In this decoding method, first, an imaging device images an area corresponding to the first portion P1 of the printed matter 1 while the illumination device illuminates the area corresponding to the first portion P1 of the printed matter 1 . Thus, the reading unit 22 acquires the first image data (step S1). The reading unit 22 outputs this first image data to the processing unit 211 . Further, the reading unit 22 captures an image of the area corresponding to the second portion P2 of the printed matter 1 and outputs the acquired image data to the processing unit 211 .

The processing unit 211 decrypts the key information from the image data obtained by imaging the area corresponding to the second part P2 and the information stored in the storage unit 212 . The key information includes, for example, the resolution of the second image data, the brightness threshold used when adjusting the resolution, and information on the relationship between the image density and the first and second arrays. Alternatively, the storage unit 212 stores a plurality of options for each of the resolution of the second image data, the brightness threshold used when adjusting the resolution, and the relationship between the image density and the first and second arrays. If so, the key information contains information indicating which one to select.

Next, the processing unit 211 adjusts the resolution of the first image data (step S2). For example, when the first image data is high-resolution image data, second image data with lower resolution is generated from the first image data based on information or key information stored in the storage unit 212 .

When the first image data is high-resolution image data, the area corresponding to the first pattern PT1, the area corresponding to the second pattern PT2, and the area corresponding to the third pattern PT3 have the same image density. Therefore, the regions cannot be distinguished based on image density.

If the resolution is lowered, the area corresponding to the first pattern PT1 and the area corresponding to the second pattern PT2 may be separated due to the difference in shape between the first sub-pattern SPT1, the second sub-pattern SPT2, and the third sub-pattern SPT3. and the area corresponding to the third pattern PT3, there is a difference in image density.

FIG. 12 depicts a high resolution image I1 of the first sub-pattern SPT1. By reducing the resolution of this high-resolution image I1 so that one pixel corresponds to one square of the grid GR, a low-resolution image I1' shown in FIG. 13 is obtained.

Here, when the ratio of bright pixels to all pixels positioned in a certain square of the grid GR exceeds 50%, the pixels of the low-resolution image I1' corresponding to this square are made bright pixels. Further, when the ratio of bright pixels to all pixels located in a certain square of the grid GR is 50% or less, the pixels of the low-resolution image I1' corresponding to this square are set as dark pixels.

When similar processing is performed on the high resolution image of the second sub-pattern SPT2, a low resolution image I2' shown in FIG. 14 is obtained. Furthermore, when similar processing is performed on the high-resolution image of the third sub-pattern SPT3, a low-resolution image I3' shown in FIG. 15 is obtained.

In the above example, the first sub-pattern SPT1, the second sub-pattern SPT2, and the third sub-pattern SPT3 have the same area and the same arrangement period. On the other hand, the low-resolution image I1', the low-resolution image I2', and the low-resolution image I3' have different areas. Therefore, by reducing the resolution of the first image data, the difference in image density can be obtained among the area corresponding to the first pattern PT1, the area corresponding to the second pattern PT2, and the area corresponding to the third pattern PT3. occur. In this way, the processing unit 211 generates a plurality of patterns with different image densities from the image data whose resolution has been adjusted (step S3). Note that this resolution adjustment can be omitted when the resolution of the first image data is low.

Next, the processing unit 211 uses the key information to decode the two-dimensional code from a plurality of patterns with different image densities (step S4). Pattern matching, for example, is used to decode the two-dimensional code.

After that, the processing unit 211 decodes the original information from the two-dimensional code (step S5). The processing unit 211 generates other information from this original information in some cases. The processing unit 211 outputs one or more of the decoded two-dimensional code, the original information obtained by decoding this two-dimensional code, and the information generated using this original information to the output unit 23 (step S6).

The output unit 23 converts the information output by the processing unit 211 into a form perceivable by humans, such as an image, sound, vibration, light, or a combination thereof, and outputs the information.

FIG. 16 is a diagram showing an example of a decoded two-dimensional code.
According to the decoding method described above, for example, the two-dimensional code CD shown in FIG. 16 can be obtained.

The information recorded on the first portion P1 of the printed matter 1 described above is difficult to read by a person who does not know how to read it. This will be explained below.

FIG. 17 is a plan view schematically showing printed matter according to the first comparative example. FIG. 18 is a cross-sectional view of the printed matter shown in FIG. 17 taken along line XVIII--XVIII.

A printed matter 1A shown in FIGS. 17 and 18 includes a substrate 11 and a printed layer 12A provided thereon. The printed layer 12A constitutes a two-dimensional code.

When the printed layer 12A is formed of process ink, the fact that the two-dimensional code is recorded on the printed matter 1A can be easily perceived by observation with the naked eye. Moreover, even when the printed layer 12A is formed of invisible ink, the fact that the two-dimensional code is recorded on the printed matter 1A can be easily perceived from the unevenness of the surface.

FIG. 19 is a plan view schematically showing a printed matter according to the second comparative example. 20 is a cross-sectional view along line XX-XX of the printed matter shown in FIG. 19. FIG.

A printed matter 1B shown in FIGS. 19 and 20 includes a substrate 11, a printed layer 12B, and a protective layer 13. FIG. The printed layer 12B is provided on the base material 11 and constitutes a two-dimensional code. The protective layer 13 is provided on the printed layer 12B. The protective layer 13 covers the entire surface of the substrate 11 on which the printed layer 12B is provided.

If the printed layer 12B is made of process ink, the protective layer 13 should be transparent. Therefore, in this case, the fact that the two-dimensional code is recorded on the printed matter 1B can be easily perceived by observation with the naked eye. Also, the surface of the protective layer 13 may have unevenness corresponding to the pattern of the printed layer 12B. Therefore, even if the printed layer 12B is formed with invisible ink, or the printed layer 12B is formed with infrared emitting ink or infrared absorbing ink and a protective layer 13 that blocks visible light is used, printed matter The fact that the two-dimensional code is recorded on 1B can be perceived from the unevenness of the surface. In order to obtain the protective layer 13 having no irregularities on the surface, the protective layer 13 having a thickness of 20 μm or more, for example, must be formed by performing screen printing, offset printing, or the like multiple times.

FIG. 21 is a plan view schematically showing printed matter according to the third comparative example. FIG. 22 is a cross-sectional view of the printed matter shown in FIG. 21 taken along line XXII-XXII.

A printed matter 1C shown in FIGS. 21 and 22 includes a substrate 11 and a printed layer 12C provided thereon. The printed layer 12C includes a first printed layer 12C1 and a second printed layer 12C2. The first printed layer 12C1 constitutes a two-dimensional code. The second printed layer 12C2 is made of ink different from the ink forming the first printed layer 12C1. The second printed layer 12C2 constitutes the background of the two-dimensional code.

When the first printed layer 12C1 and the second printed layer 12C2 are formed of process ink, there is a trade-off relationship between a high contrast ratio and easiness of perception by observation with the naked eye.

When one of the first printed layer 12C1 and the second printed layer 12C2 is formed with a special ink and the other is formed with a process ink of the same color as the special ink, a two-dimensional code is recorded on the printed matter 1C. This is considered to be difficult to perceive by observation with the naked eye. Also, in this case, if the thickness of the first printed layer 12C1 and the thickness of the second printed layer 12C2 are matched, the surface of the printed layer 12C can be prevented from becoming uneven corresponding to the pattern of the first printed layer 12C1. It is possible.

However, even in this case, when observing the reflected light from the printed layer 12C, the difference in gloss between the first printed layer 12C1 and the second printed layer 12C2 indicates that the two-dimensional code is recorded on the printed matter 1C. , can be easily perceived by observation with the naked eye. In addition, unless the thickness of the first printed layer 12C1 and the thickness of the second printed layer 12C2 are completely matched, the fact that the two-dimensional code is recorded on the printed matter 1C can be visually observed from the difference in thickness between them. can be easily perceived at Furthermore, it is difficult to form the first printed layer 12C1 and the second printed layer 12C2 so that they do not partially overlap and there is no gap between them. When the first printed layer 12C1 and the second printed layer 12C2 partially overlap or a gap is formed between them, the printed layer 12C has ridge-like projections or grooves along the outline of the two-dimensional code pattern. will occur. Therefore, the fact that the two-dimensional code is recorded on the printed matter 1C can be easily perceived by observation with the naked eye.

On the other hand, in the printed matter 1 described with reference to FIGS. The area ratios of the sub-patterns occupying the region are made equal to each other. And the same material is used for those patterns. Therefore, when observed with the naked eye, the area provided with the pattern appears as an area having the same color throughout.

In addition, the procedure described above is required for decoding the two-dimensional code. Decoding of the information is therefore difficult for those who do not know this procedure.
Therefore, the information recorded on the first portion P1 of the printed matter 1 described above is difficult to read by a person who does not know how to read it.

In this printed matter 1, the first array forming the two-dimensional code consists of the first pattern PT1, and the second array forming the background of the two-dimensional code consists of the second pattern PT2 and the third pattern PT3. That is, the second array forming the background of the two-dimensional code consists of a plurality of patterns. Therefore, even if there is a difference in brightness between patterns in an image captured by a digital camera or a copy obtained by copying with a copier, the plurality of patterns corresponding to the background of the two-dimensional code are two-dimensional. Obstructs the perception of dimensional codes.

Therefore, in this respect as well, it is difficult for a person who does not know the reading method to read the information recorded in the first portion P1 of the printed matter 1 described above.

Next, a second embodiment of the invention will be described.
FIG. 23 is a plan view showing an enlarged part of the printed matter according to the second embodiment of the invention.

The printed matter 1 shown in FIG. 23 is the same as the printed matter 1 described with reference to FIGS. 1 to 9 except for the following points. That is, in the printed matter 1 shown in FIG. 23, the first array constituting the two-dimensional code consists of the first pattern PT1 and the second pattern PT2, and the second array constituting the background of the two-dimensional code is the third pattern PT3. consists of

This printed matter 1 has the same effects as the printed matter 1 described with reference to FIGS.

In this printed matter 1, the first array forming the two-dimensional code consists of the first pattern PT1 and the second pattern PT2, and the second array forming the background of the two-dimensional code consists of the third pattern PT3. That is, the first array forming the two-dimensional code consists of a plurality of patterns. Therefore, even if there is a difference in brightness between patterns in an image obtained by a digital camera or a copy obtained by copying with a copier, the two-dimensional code is difficult to perceive.

Therefore, in this respect as well, it is difficult for a person who does not know the reading method to read the information recorded in the first portion P1 of the printed matter 1 described above.

Next, a third embodiment of the invention will be described.
FIG. 24 is a plan view showing an enlarged part of the printed matter according to the third embodiment of the invention.

The printed matter 1 shown in FIG. 24 is the same as the printed matter 1 described with reference to FIGS. 1 to 9 except for the following points. That is, in the printed matter 1 shown in FIG. 24, the first array forming the two-dimensional code consists of the first pattern PT1 and the second pattern PT2, and the second array forming the background of the two-dimensional code consists of the third pattern. It consists of PT3 and a fourth pattern PT4.

The fourth pattern PT4 consists of a plurality of fourth sub-patterns (not shown). The fourth sub-pattern is different in shape from the first sub-pattern SPT1, the second sub-pattern SPT2 and the third sub-pattern SPT3. The fourth sub-patterns are arranged in two directions. Here, the fourth sub-patterns are arranged with the same period in the X direction and the Y direction.

The fourth pattern PT4 is made of the same material as the first pattern PT1, the second pattern PT2 and the third pattern PT3. The fourth pattern PT4 has the same sub-pattern area ratio in the unit area as the first pattern PT1, the second pattern PT2, and the third pattern PT3.

This printed matter 1 has the same effects as the printed matter 1 described with reference to FIGS.

In this printed matter 1, the first array forming the two-dimensional code consists of the first pattern PT1 and the second pattern PT2, and the second array forming the background of the two-dimensional code consists of the third pattern PT3 and the second pattern PT2. It consists of 4 patterns PT4. That is, the first array constituting the two-dimensional code consists of a plurality of patterns, and the second array constituting the background of the two-dimensional code also consists of a plurality of patterns. Therefore, even if there is a difference in brightness between patterns in an image obtained by a digital camera or a copy obtained by copying with a copier, the two-dimensional code is extremely difficult to perceive.

Therefore, in this respect as well, it is difficult for a person who does not know the reading method to read the information recorded in the first portion P1 of the printed matter 1 described above.

Various structures can be employed for the subpatterns.
FIG. 25 is a plan view schematically showing a modified example of the first pattern. FIG. 26 is a plan view schematically showing a modified example of the second pattern. FIG. 27 is a plan view schematically showing a modified example of the third pattern.

In the first pattern PT1 shown in FIG. 25, the first sub-pattern SPT1 is a line segment extending in the Y direction. These first sub-patterns SPT1 are arranged in the X direction and the Y direction, and the first sub-patterns SPT1 adjacent in the Y direction are in contact with each other. As a result, the first sub-patterns SPT1 form a stripe arrangement.

In the second pattern PT2 shown in FIG. 26, the second sub-pattern SPT2 is circular. These second sub-patterns SPT2 are arranged with the same period in the X direction and the Y direction. The second sub-patterns SPT2 are spaced apart from each other to form a polka dot arrangement.

In the third pattern PT3 shown in FIG. 27, the third sub-pattern SPT3 is "X"-shaped. That is, the third sub-pattern SPT3 has a shape in which two line segments are orthogonal to each other. Each third sub-pattern SPT3 is oriented such that one line segment forming it is parallel to the X direction and the other line segment is parallel to the Y direction.

These third sub-patterns SPT3 are arranged in the X direction and the Y direction. The third sub-patterns SPT3 adjacent in the X direction are in contact with each other, and the third sub-patterns SPT3 adjacent in the Y direction are also in contact with each other. As a result, the third sub-patterns SPT3 form a square lattice arrangement.

In this way, various structures can be adopted for subpatterns.
Each sub-pattern is preferably circular, as shown in FIG. 26, or has concentric contours, as shown in FIGS.

The subpatterns typically protrude with respect to the surface of the substrate. Therefore, for example, when the first pattern PT1 shown in FIG. 25 is formed of process ink, the printed material 1 is tilted around the axis parallel to the X direction and the axis parallel to the Y direction. A difference in brightness occurs when the printed matter 1 is tilted around. Also, when the third pattern PT3 shown in FIG. 27 is formed from process ink, the third pattern PT3, when the printed matter 1 is tilted around an axis parallel to the X direction, is perpendicular to the Z direction and is perpendicular to the X direction. A difference in brightness occurs when the printed product 1 is tilted about an axis which forms an angle of 45° with respect to it. As a result, any one of the first pattern PT1, the second pattern PT2, and the third pattern PT3 may be distinguishable from the remaining patterns when observed with the naked eye.

If each sub-pattern is circular or has concentric contours, it will not produce the brightness differences described above. Therefore, by adopting this structure, it is possible to make it more difficult for a person who does not know how to read the information to read the information.
In the above-described embodiment, the pattern constituting the two-dimensional code has a structure in which cells having a substantially square shape are arranged in the X direction and the Y direction. can also be configured with patterns having structures aligned in other directions. For example, the two-dimensional code may be configured with a pattern having a structure in which cells are arranged concentrically. In this case, the areas of those cells need not be uniform.
In the above embodiment, the two directions in which the sub-patterns are arranged are linear directions, but these directions are not limited to linear directions. For example, one of the two directions in which the sub-patterns are arranged may be a curved direction such as an arc, and the other may be a straight line direction that intersects the previous curved line.

<Example>
A printed product 1 as described with reference to FIGS. 1 to 9 was produced.
Specifically, coated paper was used as the base material 11 . The first portion P1 was formed using an infrared emitting ink. As the infrared light emitting ink, an ultraviolet curable offset printing ink containing an infrared light emitting phosphor which is excited by irradiation with infrared light and emits infrared light having a longer wavelength than the excitation light was used. Moreover, the protective layer 13 was formed using process ink. As the process ink, modified UV161 Conch White, which is a white ink manufactured by T&K TOKA, was used. Note that the second portion P2 and the third portion P3 are omitted.

The two-dimensional code recorded on this printed matter 1 was decoded using the decoding system 2 described with reference to FIG. Here, the information described above regarding the key information is stored in the storage unit 212 . As a result, the two-dimensional code could be decoded.

Moreover, this printed matter 1 was observed with the naked eye. As a result, the presence of the two-dimensional code could not be confirmed either when the printed matter 1 was observed from the front or obliquely with the naked eye.

<Comparative example>
A printed product 1 as described with reference to FIGS. 1 to 9 was produced.
Specifically, as the substrate 11, coated paper similar to that used in the examples was used. The first printed layer 12C1 was formed using the same infrared light-emitting ink as used in the example. The second printed layer 12C2 did not contain an infrared emitting phosphor and was formed using an ink having a composition similar to that of the infrared ink, except that a pigment was added to approximate the color of the infrared ink.

This printed matter 1 was irradiated with infrared rays as excitation light and photographed with an infrared camera. As a result, a two-dimensional code could be confirmed in the obtained image.

Moreover, this printed matter 1 was observed with the naked eye. As a result, when the printed matter 1 was observed from the front with the naked eye, the presence of the two-dimensional code could not be confirmed. However, when this printed matter 1 was observed with the naked eye from an oblique direction, the presence of the two-dimensional code could be confirmed from the difference in gloss between the first printed layer 12C1 and the second printed layer 12C2.

DESCRIPTION OF SYMBOLS 1... Printed material 1, 1A... Printed material, 1B... Printed material, 1C... Printed material, 2... Decoding system, 11... Base material, 12... Printed layer, 12A... Printed layer, 12B... Printed layer, 12C... Printed layer, 12C1... Third 1 printed layer, 12C2... second printed layer, 13... protective layer, 21... decoding device, 22... reading unit, 23... output unit, 211... processing unit, 212... storage unit, CD... two-dimensional code, GR... grid , I1...high-resolution image, I1'...low-resolution image, I2'...low-resolution image, I3'...low-resolution image, P1...first part, P2...second part, P3...third part, PT1...first pattern, PT2... second pattern, PT3... third pattern, SPT1... first sub-pattern, SPT2... second sub-pattern, SPT3... third sub-pattern.

Claims (15)

comprising a substrate and one or more printed layers provided on the substrate;
The one or more printed layers comprise a plurality of patterns made of the same material and adjacent to each other;
Each of the plurality of patterns consists of a plurality of sub-patterns arranged in two directions and having the same shape,
the plurality of patterns are different in shape of the plurality of sub-patterns included therein, and the plurality of sub-patterns occupying a unit area have the same area ratio;
A printed matter in which a first array of one or more of the plurality of patterns constitutes a one-dimensional or two-dimensional code, and a second array of the remainder of the plurality of patterns constitutes a background of the one-dimensional or two-dimensional code. . 2. The printed matter of claim 1, wherein in each of said plurality of patterns, each of said plurality of sub-patterns has circular or concentric contours. 3. The printed matter of claim 1 or 2, wherein said first array consists of two or more of said plurality of patterns. 4. The printed matter according to any one of claims 1 to 3, wherein said second array consists of two or more of said plurality of patterns. 5. The printed matter according to any one of claims 1 to 4, wherein the plurality of patterns are made of invisible ink. 6. The printed matter according to any one of claims 1 to 5, wherein the plurality of patterns are made of infrared absorbing ink or infrared emitting ink. The printed matter according to any one of claims 1 to 6, further comprising a protective layer covering the plurality of patterns. 8. The printed matter according to claim 7, wherein the protective layer blocks visible light. 9. The printed matter according to any one of claims 1 to 8, wherein in each of said plurality of patterns, each of said plurality of sub-patterns has a maximum dimension within a range of 0.5 to 30 mm. The one or more printed layers further include a pattern corresponding to key information for distinguishing the plurality of patterns into those constituting the first array and those constituting the second array. 10. The printed matter according to any one of 1 to 9. From the image obtained by imaging the area corresponding to the plurality of patterns in the printed matter according to any one of claims 1 to 10, the one-dimensional or A decoding method comprising decoding a two-dimensional code. generating a plurality of patterns having different image densities from the plurality of pattern images obtained by photographing the printed matter according to any one of claims 1 to 10;
and decoding the one-dimensional or two-dimensional code from the plurality of patterns having different image densities. 11. Based on the shapes of the plurality of sub-patterns, the A decoding device comprising a processing unit that decodes a one-dimensional or two-dimensional code. A second image containing information on a plurality of patterns with different image densities from the first image data containing information on the plurality of patterns obtained by photographing the printed matter according to any one of claims 1 to 10. A decoding device comprising a processing unit that generates data and decodes the one-dimensional or two-dimensional code from the second image data. a decoding device according to claim 13 or 14;
a reading unit that captures the printed matter and acquires the first image data;
an output unit for outputting one or more of the decoded one-dimensional or two-dimensional code, original information obtained by decoding the one-dimensional or two-dimensional code, and information generated using the original information. decoding system.

Images