Pattern formation material, case, detection method, and detector

Abstract

To provide a pattern formation material capable of securing confidential information from nondestruction detection means, a case, a detection method, and a detector.SOLUTION: A pattern formation material comprises a base material which blocks visible light and which permits the passage of a specified electromagnetic wave with a specific frequency different from the frequency of the visible light, and an attenuation pattern which is provided in the base material and which has a plurality of domains different in attenuation factor for the specific frequency from one another.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a patterning material, a case, a detection method, and a detection device. [Background technology]

[0002] In recent years, protecting confidential information from third parties has become increasingly important. For example, when sending a postcard, information security technologies are used to prevent third parties from seeing confidential information such as personal information by attaching a masking sticker to the area where the information is written. Also, for example, in industrial hardware products, information security technologies are used to store the main components containing technical information inside a housing, preventing third parties from seeing the main components unless the housing is destroyed or disassembled.

[0003] Meanwhile, in recent years, technologies have been developed that can acquire information about the area covered by a masking sticker by using electromagnetic waves in frequency bands such as millimeter waves and terahertz waves (see, for example, Patent Document 1). Also, acquiring information about the inside of a housing by X-ray photography or the like has been a common practice. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5521245 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, it is possible to make confidential information invisible to third parties by physically covering it with a shield that blocks visible light, such as a masking sticker or a housing, but it is possible to non-destructively read confidential information covered by the shield by using electromagnetic waves that penetrate the shield, such as millimeter waves, terahertz waves, X-rays, etc. Therefore, from the perspective of protecting confidential information from third parties, it is required to protect confidential information using such non-destructive detection means.

[0006] The present disclosure has been made in view of the above, and aims to provide a pattern forming material, a case, a detection method, and a detection device that are capable of protecting confidential information from non-destructive detection means. [Means for solving the problem]

[0007] The pattern forming material according to the present disclosure comprises a substrate that blocks visible light and passes specific electromagnetic waves, which are electromagnetic waves of a specific frequency different from the frequency of the visible light, and an attenuation pattern provided on the substrate and having multiple regions with different attenuation rates for the specific electromagnetic waves.

[0008] The case according to the present disclosure comprises a case body and a storage section provided inside the case body for storing an item, and the case body is formed to include the pattern forming material described above.

[0009] The detection method according to the present disclosure includes the steps of irradiating the specific electromagnetic waves onto the pattern forming material and an object covered with the pattern forming material, detecting the reflected waves or transmitted waves of the specific electromagnetic waves by the pattern forming material and the object, and extracting information about the object from the detection results based on information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern forming material.

[0010] The detection device according to the present disclosure includes a detection unit that detects the reflected waves or transmitted waves of the specific electromagnetic waves irradiated onto the pattern forming material and an object covered with the pattern forming material, and a control unit that extracts information about the object from the detection results of the detection unit based on information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern forming material. [Effects of the Invention]

[0011] According to the present disclosure, it is possible to provide a pattern forming material, a case, a detection method, and a detection device that can protect confidential information from non-destructive detection means. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram schematically illustrating an example of a pattern forming material according to this embodiment. [Figure 2] FIG. 2 is a diagram schematically showing an example of how the pattern forming material is used. [Figure 3] FIG. 3 is a diagram schematically showing another example of a usage mode of the pattern forming material. [Figure 4] FIG. 4 is a diagram schematically illustrating an example of a case according to this embodiment. [Figure 5] FIG. 5 is a diagram schematically illustrating an example of how the case is used. [Figure 6] FIG. 6 is a flowchart showing an example of the detection method of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of a pattern forming material, a case, a detection method, and a detection device according to the present disclosure will be described with reference to the drawings. Note that the present invention is not limited to these embodiments. Furthermore, the components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially identical.

[0014] 1 is a diagram schematically illustrating an example of a pattern formation material 100 according to this embodiment. As shown in FIG. 1, the pattern formation material 100 includes a substrate 10 and an attenuation pattern 20.

[0015] The substrate 10 blocks visible light. In this embodiment, the substrate 10 is in the form of a sheet such as paper or film. The substrate 10 allows electromagnetic waves of a specific frequency different from the frequency of visible light (hereinafter referred to as specific electromagnetic waves) to pass through. Examples of the specific electromagnetic waves include at least one of terahertz waves, microwaves, millimeter waves, X-rays, and infrared rays. In this embodiment, a case where terahertz waves are used as the specific electromagnetic waves will be described as an example.

[0016] The attenuation pattern 20 is provided on the substrate 10. The attenuation pattern 20 has a spatial distribution of the attenuation rate for a specific electromagnetic wave. In other words, when a specific electromagnetic wave is irradiated onto the attenuation pattern 20, the intensity of the specific electromagnetic wave that passes through the attenuation pattern 20 varies depending on the location. The attenuation pattern 20 is formed, for example, by being printed on the surface 10a of the substrate 10.

[0017] The attenuation pattern 20 has an attenuation layer 21. The attenuation layer 21 is formed in a layered form using, for example, a material that is a mixture of multiple substances that have different absorption rates for absorbing specific electromagnetic waves. Examples of such multiple substances that can be used include various materials such as rubber, metal, wood, and highly absorbent polymers. The attenuation pattern 20 has a mixture ratio of such multiple substances that varies depending on the location. This configuration forms a spatial distribution of the attenuation rate of the specific electromagnetic waves.

[0018] In the present embodiment, the attenuation pattern 20 has attenuation layers 21 formed in a plurality of regions 22, each having a different mixture ratio of a plurality of materials. The plurality of regions 22 are, for example, rectangular (square) and arranged in a matrix. The shape and arrangement of the plurality of regions 22 are not limited to those described above, and may be shapes other than rectangular (circular, triangular, or other polygonal shapes), or may be arranged in a different manner from the matrix (e.g., staggered). Attenuation layers 21 having different absorption rates for specific electromagnetic waves are arranged in each of the plurality of regions 22. This forms an attenuation pattern 20 in which the attenuation rate of the specific electromagnetic wave differs for each region 22. The attenuation layers 21 do not need to be arranged in all regions 22. For example, by arranging the attenuation layers 21, a distribution of the attenuation rate of the specific electromagnetic wave may be formed between the regions 22 in which the attenuation layers 21 are not arranged and the regions 22 in which the attenuation layers 21 are not arranged.

[0019] When forming the pattern forming material 100, the attenuation layer 21 is printed on the surface of the substrate 10 for each region 22 using ink containing a mixture of multiple substances with different absorption rates for specific electromagnetic waves. In this case, for example, multiple types of ink are prepared, each with a different mixture amount or mixing ratio of the multiple substances. When printing the attenuation pattern 20, a different type of ink is printed for each region 22 of the attenuation pattern 20. The type of ink to be printed in each region 22, i.e., the correspondence between the region 22 and the type of ink, can be set, for example, using pseudorandom numbers. The correspondence between the region 22 and the type of ink can be further correlated with the type of ink and the attenuation rate, and can be used as data indicating the attenuation rate for each region 22. The relationship between the type of ink and the attenuation rate can be determined in advance by measurement, simulation, etc.

[0020] By changing the combination of the position of the region 22 and the absorption rate of the specific electromagnetic wave, it is possible to form multiple types of attenuation patterns 20 with different distributions of the absorption rate of the specific electromagnetic wave. Therefore, it is possible to form multiple types of pattern forming materials 100 in which attenuation patterns 20 with different distributions of the absorption rate of the specific electromagnetic wave are arranged.

[0021] Next, an example of how the pattern forming material 100 configured as described above is used will be described. Fig. 2 is a diagram schematically showing an example of how the pattern forming material 100 is used. In Fig. 2, an example will be described in which the target object 30 is a piece of paper (such as a postcard) on whose surface information 31 is recorded. The target object 30 is not limited to paper, and may be another object.

[0022] In the state (ST1) where the part of the object 30 on which the information 31 is recorded is exposed, the information 31 can be easily read by a third party by visually inspecting it.

[0023] When a general shielding sheet 32 ​​made of, for example, paper and adhesive is attached to the portion of the object 30 on which the information 31 is recorded (ST2), a third party cannot read the information by visual inspection alone. On the other hand, by scanning the information 31 by irradiating it with electromagnetic waves such as terahertz waves that pass through the shielding sheet using, for example, a general scanning device 34, the intensity distribution of the electromagnetic waves reflected from the information 31 can be obtained, and the information 31 covered by the shielding sheet 32 ​​can be read.

[0024] In contrast, in the state (ST3) where the pattern forming material 100 according to this embodiment is attached to the portion of the object 30 on which the information 31 is recorded, a third party cannot read the information by merely visually inspecting it. Furthermore, when a general scanning device 34 is used to irradiate and scan a specific electromagnetic wave such as a terahertz wave that transmits through the substrate 10, the electromagnetic wave intensity distribution reflected from the information 31 is attenuated by the attenuation pattern 20, but a third party who does not have spatial distribution information on the attenuation rate of the attenuation pattern 20 cannot read the information 31 covered with the pattern forming material 100.

[0025] On the other hand, when using a scanning device 35 that is provided with information on the correspondence between the region 22 of the attenuation pattern 20 and the attenuation rate of the specific electromagnetic wave (Figure 2: correspondence information), the information 31 covered by the pattern forming material 100 can be read by performing image processing on the image detected using the specific electromagnetic wave using the correspondence information.

[0026] Fig. 3 is a diagram schematically illustrating another example of a usage mode of the pattern forming material 100. As shown in Fig. 3, a plurality of pattern forming materials 100 having different attenuation patterns 20 may be arranged so as to be stacked on the target object 30. This configuration makes it possible to increase the number of patterns of attenuation rate distribution.

[0027] Fig. 4 is a diagram schematically illustrating an example of a case 300 according to this embodiment. The case 300 shown in Fig. 4 includes a case main body 301 and a storage section 302. An example of the case 300 is an attaché case. Note that the case 300 is not limited to an attaché case, and may have any other configuration as long as it is a storage structure capable of storing items inside.

[0028] The case body 301 is formed including a pattern forming material 200. The pattern forming material 200 has a base material 110 and an attenuation pattern 120. The base material 110 is, for example, plate-shaped and forms the framework of the case body 301. The base material 110 blocks visible light, similar to the base material 10 described above. The base material 110 passes specific electromagnetic waves with frequencies different from those of visible light. In the example shown in FIG. 4, a case where X-rays are used as the specific electromagnetic waves will be described. The base material 110 is formed using, for example, wood, plastic, or other resin material that is transparent to X-rays.

[0029] The attenuation pattern 120 is provided on the base material 110. The attenuation pattern 120 has a spatial distribution of attenuation rates for specific electromagnetic waves. The attenuation pattern 120 has a plurality of metal plates 121 of different thicknesses attached to the base material 110. The metal plates 121 are formed using a single metal or an alloy of aluminum, iron, tungsten, etc. The metal plates 121 have different X-ray absorption rates (attenuation rates) depending on their thicknesses. Note that while FIG. 4 shows a state in which the attenuation pattern 120 is schematically illustrated (white, black, gray) on the case body 301, in reality the case body 301 is covered with an exterior member (not shown) or the like, and therefore the attenuation pattern 120 is not visible from the outside.

[0030] The attenuation pattern 120 is formed by closely attaching metal plates 121 of different thicknesses as described above to regions 122 partitioned on the surface of the base material 110. The multiple regions 122 are, for example, rectangular (square) and arranged in a matrix. The shape and arrangement of the multiple regions 122 are not limited to those described above, and other shapes and arrangements are also possible. In the multiple regions 122, metal plates 121 with different absorption rates of the specific electromagnetic wave are arranged in each region 122. This forms an attenuation pattern 120 in which the attenuation rate of the specific electromagnetic wave differs for each region 122.

[0031] It is possible to set, using pseudo-random numbers, which thickness of metal plate 121 is to be placed in which region 122, i.e., the correspondence between the region 122 and the thickness of metal plate 121. The correspondence between the region 122 and the thickness of metal plate 121 can be used as data indicating the attenuation rate for each region 122 by further associating the relationship between the thickness of metal plate 121 and the attenuation rate.

[0032] By changing the combination of the position of the region 122 and the absorption rate of the specific electromagnetic wave, it is possible to form multiple types of attenuation patterns 120 with different distributions of the absorption rate of the specific electromagnetic wave. Therefore, the case body 301 is configured to include the pattern forming material 200 having attenuation patterns 120 with different distributions of the absorption rate of the specific electromagnetic wave.

[0033] Next, an example of how the case 300 configured as described above is used will be described. FIG. 5 is a diagram schematically illustrating an example of how the case 300 is used. FIG. 5 shows a case 300A, which is a comparative example of the case 300 according to this embodiment. The case 300A is a general case that does not include the pattern formation material 200. FIG. 5 illustrates an example in which an object 330 such as a gear is housed in each of the cases 300 and 300A. The object 330 is not limited to an industrial product such as a gear, and may be other items such as documents.

[0034] When an object 330 is housed in the housing portions 302, 302A of the cases 300, 300A and X-rays are irradiated onto the cases 300, 300A from the irradiation units 255, 255A, respectively, to perform an internal inspection, the X-rays pass through the case 300A, and some of the X-rays are absorbed by the object 330, attenuating the amount of X-rays before being irradiated onto the detection unit 251A. Therefore, the intensity of the X-rays reaching the detection unit 251A has an intensity contrast between the X-rays that pass through the object 330 and the X-rays that do not pass through the object 330, making it possible to acquire an image of the object 330.

[0035] In contrast, in the case 300, the case body 301 is formed in a state in which it contains the pattern forming material 200, and therefore the intensity of the X-rays detected by the detection unit 251 is a combination of the attenuation of the dose caused by the object 330 and the attenuation caused by the pattern forming material 200, and a third party who does not have information on the spatial distribution of the attenuation rate of the pattern forming material 200 cannot read information such as the shape of the object 330 contained in the container 302 from the detection results.

[0036] On the other hand, when information on the correspondence between the region 122 of the attenuation pattern 120 and the attenuation rate of the specific electromagnetic wave is given, the information on the correspondence can be used to perform image processing on the image detected using the specific electromagnetic wave, thereby reading information on the object 330 contained in the storage section 302 of the case 300.

[0037] FIG. 5 is a schematic diagram illustrating an example of a detection device 250 that detects information about an object 330 covered with the pattern-forming material 200 of this embodiment. As shown in FIG. 5, the detection device 250 includes a detection unit 251 and a control unit 252. The detection unit 251 detects transmitted waves of specific electromagnetic waves irradiated onto the pattern-forming material 200 and the object 330 covered with the pattern-forming material 200. The control unit 252 extracts information about the object 330 from the detection result of the detection unit 251 based on information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern-forming material 200. The control unit 252 includes a processor such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), and a storage such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The storage stores information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern-forming material 200. The processor extracts information about the object 330 from the detection result of the detector 251 based on the information about the spatial distribution of the attenuation rate stored in the storage.

[0038] 6 is a flowchart showing an example of the detection method of this embodiment. The detection method of this embodiment detects information about the objects 30 and 330 when the objects 30 and 330 are covered with the pattern formation materials 100 and 200.

[0039] First, in a state where the target objects 30, 330 are covered with the pattern formation materials 100, 200, the pattern formation materials 100, 200 and the target objects 30, 330 are irradiated with specific electromagnetic waves (step S10).

[0040] Next, the specific electromagnetic wave reflected or transmitted by the pattern forming materials 100, 200 and the objects 30, 330 is detected (step S20).

[0041] Next, information on the target objects 30, 330 is extracted from the detection results in step S20 based on information on the spatial distribution of the attenuation rate of the specific electromagnetic wave in the pattern formation materials 100, 200 (step S30).

[0042] As described above, according to the first aspect of the present disclosure, there is provided a pattern forming material 100, 200 comprising a substrate 10, 110 that blocks visible light and passes specific electromagnetic waves, which are electromagnetic waves of a specific frequency different from the frequency of visible light, and an attenuation pattern 20, 120 provided on the substrate 10, 110 and having multiple regions 22, 122 with different attenuation rates for the specific electromagnetic waves.

[0043] According to this configuration, when nondestructive detection is performed by irradiating specific electromagnetic waves onto attenuation patterns 20, 120 having multiple regions 22, 122 with different attenuation rates for the specific electromagnetic waves, an image corresponding to the attenuation patterns 20, 120 is detected when detection is performed based on the reflected or transmitted waves of the specific electromagnetic waves. Therefore, when an object is covered with the pattern forming material 100, it becomes difficult to detect the object using the specific electromagnetic waves. By using such a pattern forming material 100, it becomes possible to protect confidential information. Furthermore, since the attenuation rate can be set for each region 22, 122, the relationship between a position in the attenuation pattern 20, 120 and the attenuation rate at that position can be easily understood.

[0044] According to a second aspect of the present disclosure, in the pattern formation material of the first aspect, the specific electromagnetic wave is at least one of terahertz waves, microwaves, millimeter waves, X-rays, and infrared rays.

[0045] According to this configuration, when at least one of terahertz waves, microwaves, millimeter waves, X-rays, and infrared rays is used as the specific electromagnetic wave, it is possible to protect confidential information.

[0046] According to a third aspect of the present disclosure, in the pattern forming material according to the first or second aspect, the substrate 10, 110 is sheet-shaped or plate-shaped, and the attenuation pattern 20, 120 is disposed on the surface of the substrate 10, 110.

[0047] According to this configuration, the pattern formation materials 100 and 200 can be easily formed.

[0048] According to a fourth aspect of the present disclosure, in the pattern forming material according to the first aspect, the plurality of regions 22, 122 are arranged in a matrix.

[0049] According to this configuration, the plurality of regions 22, 122 are arranged in a matrix, so that the relationship between the position in the attenuation pattern 20, 120 and the attenuation rate at that position can be easily grasped.

[0050] According to a fifth aspect of the present disclosure, a case is provided which comprises a case body 301 and a storage section 302 provided inside the case body 301 for storing an item, wherein the case body 301 is formed to include the above-mentioned pattern forming material 200.

[0051] According to this configuration, when non-destructive detection is performed by irradiating specific electromagnetic waves, information about the items stored in the storage section 302 can be appropriately preserved.

[0052] According to a sixth aspect of the present disclosure, there is provided a detection method including the steps of irradiating specific electromagnetic waves to a pattern forming material 100, 200 described in any one of the first to fourth aspects and an object 30, 330 covered with the pattern forming material 100, 200, detecting reflected waves or transmitted waves of the specific electromagnetic waves by the pattern forming material 100, 200 and the object 30, 330, and extracting information about the object 30, 330 from the detection results based on information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern forming material 100.

[0053] According to this configuration, when non-destructive detection is performed by irradiating specific electromagnetic waves, information on the target objects 30, 330 can be appropriately extracted.

[0054] According to a seventh aspect of the present disclosure, there is provided a detection device comprising: a detection unit 51, 251 that detects reflected waves or transmitted waves of specific electromagnetic waves irradiated onto a pattern forming material 100, 200 described in any one of the first to sixth aspects and an object 30, 330 covered with the pattern forming material 100, 200; and a control unit 52, 252 that extracts information about the object 30, 330 from the detection results of the detection unit 51, 251 based on information about the spatial distribution of the attenuation rate of the specific electromagnetic waves in the pattern forming material 100, 200.

[0055] According to this configuration, when non-destructive detection is performed by irradiating specific electromagnetic waves, information on the target objects 30, 330 can be appropriately extracted. [Explanation of symbols]

[0056] 10,110 Base material 10a surface 20,120 Decay Pattern 21 Damping Layer 22,122 areas 30,330 objects 31 Information 32 Shielding sheet 100,200 Pattern forming material 121 Metal plate 250 Detection Device 251 Detector 252 Control Unit 300,300A case 301 Case body 302,302A storage unit

Claims

1. a substrate that blocks visible light and transmits specific electromagnetic waves that are electromagnetic waves with a specific frequency different from the frequency of the visible light; an attenuation pattern provided on the base material and having a plurality of regions with different attenuation rates for the specific electromagnetic wave; A pattern forming material comprising:

2. The specific electromagnetic wave is at least one of terahertz waves, microwaves, millimeter waves, X-rays, and infrared rays. The pattern forming material according to claim 1 .

3. The substrate is in the form of a sheet or a plate, The attenuation pattern is disposed on a surface of the substrate. The pattern forming material according to claim 1 .

4. The plurality of regions are arranged in a matrix. The pattern forming material according to claim 1 .

5. The case body and a storage section provided inside the case body for storing articles; Equipped with The case body is formed by including the pattern forming material according to claim 1. case.

6. a step of irradiating the specific electromagnetic wave onto the pattern forming material according to claim 1 and an object covered with the pattern forming material; detecting a reflected wave or a transmitted wave of the specific electromagnetic wave by the pattern forming material and the object; extracting information about the object from the detection result based on information about the spatial distribution of the attenuation rate of the specific electromagnetic wave in the pattern formation material; A detection method comprising:

7. a detection unit that detects a reflected wave or a transmitted wave of the specific electromagnetic wave irradiated onto the pattern formation material according to claim 1 and an object covered with the pattern formation material; a control unit that extracts information about the object based on information about a spatial distribution of an attenuation rate of the specific electromagnetic wave in the pattern formation material from a detection result of the detection unit; and A detection device comprising:

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