CN112906843B - An infrared-based anti-counterfeiting method and system - Google Patents

Abstract

The invention relates to an infrared-based anti-counterfeiting method and system, the method comprising: constructing an anti-counterfeiting pattern on a substrate, the anti-counterfeiting pattern is composed of at least two graphic units, and the graphic units are used to interact with infrared rays; Arranging at least one infrared detector at the position; the position of the infrared light source matched with the predetermined position; by identifying all the infrared patterns to complete the anti-counterfeiting identification of the anti-counterfeiting pattern; wherein, when the infrared light source is located at a certain position of the infrared light source, the infrared light source generates The infrared rays generated by the infrared light source interact with different graphic units to generate infrared patterns of different colors, and/or when the infrared light source is located at different positions of the infrared light source, the infrared rays generated by the infrared light source interact with different graphic units to generate different infrared patterns. The invention can reduce the cost, energy consumption and other problems caused by the use of artificial light sources in the existing optical anti-counterfeiting technology, and at the same time improve the portability and intelligence of the anti-counterfeiting technology.

Description

An infrared-based anti-counterfeiting method and system

technical field

The invention belongs to the technical field of anti-counterfeiting, and in particular relates to an anti-counterfeiting method and system based on infrared rays.

Background technique

The problem of counterfeit and shoddy existing products has always been a challenge that the whole world is facing. It is pervasive in all aspects of our daily life, such as food, clothing, housing and transportation. It will not only cause economic losses, but also threaten human health (such as fake and shoddy drugs, food, etc.). Advanced anti-counterfeiting technology is an important means to combat counterfeit and shoddy products. Among them, the optical anti-counterfeiting technology is a widely used technology, which recognizes the anti-counterfeiting pattern through the interaction between light and the anti-counterfeiting pattern. However, the existing optical anti-counterfeiting technology often needs to use artificial light sources to provide light in specific bands during the identification process. The use of these artificial light sources not only increases the cost and energy consumption of anti-counterfeiting technology, but also some of these light sources are not easy to carry. , for the anti-counterfeiting process has brought a lot of inconvenience.

According to the principle of black body radiation, any object with a temperature higher than absolute zero (0K) is constantly radiating electromagnetic waves. As a warm-blooded animal, human beings maintain their body temperature at around 37°C (310K), so the human body is constantly radiating electromagnetic waves. By calculating the Planck distribution function, it can be found that the electromagnetic waves radiated by the human body are mainly concentrated in the mid-infrared band (3-25μm), so the human body is a natural infrared light source, and various parts including hands, faces, etc. can be used as independent Infrared light source. For example, the existing infrared temperature measuring gun is to measure the body temperature of the human body in real time and non-contact by detecting the infrared light radiated by the human body. Therefore, how to use the infrared light radiated by the human body as a light source for anti-counterfeiting identification is a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

In view of the above-mentioned defects in the prior art, the object of the present invention is to provide an infrared-based anti-counterfeiting method and system, which can reduce the cost and energy consumption caused by the use of artificial light sources in the existing optical anti-counterfeiting technology, while improving The portability and intelligence of anti-counterfeiting technology.

In a first aspect, the present invention provides an infrared-based anti-counterfeiting method, comprising:

An anti-counterfeiting pattern is constructed on the substrate, the anti-counterfeiting pattern is composed of at least two graphic units, and the graphic units are used to interact with infrared rays;

Arranging at least one infrared detector at a predetermined position for capturing the infrared pattern after the interaction between the infrared rays and the graphics unit;

The position of the infrared light source matched with the predetermined position, the position of the infrared light source is used to place the infrared light source, so that the infrared detector captures at least one corresponding infrared pattern;

Place an infrared light source at the position of the infrared light source;

Complete the anti-counterfeiting recognition of the anti-counterfeiting pattern by identifying all the infrared patterns;

Wherein, when the infrared light source is located at a certain infrared light source position, the infrared rays generated by the infrared light source interact with different graphic units to generate infrared patterns of different colors, and/or when the infrared light source is located at a different infrared light source position, the infrared light source The generated infrared rays interact with different graphics units to generate different infrared patterns.

Wherein, the infrared light source includes hands or other arbitrary parts of the human body.

Wherein, the interaction includes at least one or more of reflection, diffraction, interference, absorption and transmission.

Wherein, the anti-counterfeiting pattern at least includes a graphic unit composed of a polymer or a metal film that reflects or absorbs infrared rays, a graphic unit composed of a metal grating that diffracts infrared rays, or a multi-layer structure that interferes with infrared rays. One or more of the graphic units formed by film materials.

Wherein the anti-counterfeiting pattern includes at least two graphic units made of polymer or metal film which reflect or absorb infrared rays, different materials of the graphic units have different reflectivity or absorptivity.

Wherein, when the anti-counterfeiting pattern includes at least two graphic units composed of metal gratings that diffract infrared rays, the metal gratings of different graphic units have different periods, orientations or duty ratios.

Wherein, when the anti-counterfeiting pattern includes at least two graphic units composed of multi-layer film materials having an interference effect on infrared rays, the multi-layer film materials of different graphic units have different film thicknesses.

Wherein, the anti-counterfeit pattern is at least one or more of two-dimensional codes, fingerprints, character strings, characters, numbers or images.

Wherein, the anti-counterfeiting identification of the anti-counterfeiting pattern is completed by identifying all the infrared patterns, including:

One or more of two-dimensional code recognition for infrared patterns, matching infrared patterns with pre-stored reference infrared patterns, or identifying meanings for infrared patterns;

According to the identification and/or matching results, the anti-counterfeiting identification is completed.

Wherein, the infrared detector is an infrared camera.

Wherein, the material of the substrate is paper material, glass, silicon chip, plastic or metal.

In a second aspect, the present invention also provides an anti-counterfeiting system implementing the above method, including:

An anti-counterfeit pattern having an infrared pattern for interacting with infrared rays;

An infrared detector, which is used to capture the infrared pattern after the interaction between the infrared ray and the anti-counterfeiting pattern;

The identification unit is used for identifying the infrared pattern to complete the anti-counterfeiting identification of the anti-counterfeiting pattern.

Compared with the prior art, the present invention sets the anti-counterfeiting pattern to be composed of different graphic units, which can make the anti-counterfeiting pattern interact with infrared rays to form infrared patterns of different colors and shapes. According to the different colors and shapes of the infrared patterns, it can complete Anti-counterfeiting identification of anti-counterfeiting patterns. And the infrared ray that human body produces can be used for the identification of the anti-counterfeiting pattern of the present application, therefore can not need artificial light source, thereby can reduce the cost and energy consumption of anti-counterfeiting identification, and operation is simpler; In addition, when using hand as infrared light source, can have Portability, controllability and intelligence; and the controllability and intelligence of the hand can improve the anti-counterfeiting level of anti-counterfeiting technology.

Description of drawings

The above and other objects, features and advantages of exemplary embodiments of the present disclosure will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the present disclosure are shown by way of illustration and not limitation, and the same or corresponding reference numerals indicate the same or corresponding parts, wherein:

Fig. 1 is a flowchart illustrating an anti-counterfeiting method based on infrared rays according to an embodiment of the present invention;

Fig. 2 is a schematic diagram showing an anti-counterfeiting mechanism based on infrared reflection according to an embodiment of the present invention;

Fig. 3 is a schematic diagram showing the effect of multi-level anti-counterfeiting according to an embodiment of the present invention;

Fig. 4 is a schematic diagram showing anti-counterfeit patterns and anti-counterfeit effects of diffraction according to an embodiment of the present invention;

Fig. 5 is a schematic diagram showing the anti-counterfeiting effect of different duty ratios during diffraction according to an embodiment of the present invention;

Fig. 6 is a schematic diagram showing an anti-counterfeit pattern of root mean square contrast change according to an embodiment of the present invention;

Fig. 7 is a schematic diagram showing an anti-counterfeiting system according to an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise, "multiple" Generally contain at least two.

It should also be noted that the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that an article or arrangement comprising a list of elements includes not only those elements but also includes items not expressly listed. other elements of the product, or elements inherent in the product or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in an article or device comprising said element.

Optional embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

Embodiment one

Referring to Figure 1, an embodiment of the present invention provides an infrared-based anti-counterfeiting method, including:

An anti-counterfeiting pattern is constructed on the substrate, the anti-counterfeiting pattern is composed of at least two graphic units, and the graphic units are used to interact with infrared rays, preferably, the material of the substrate is paper material, glass, silicon chip, plastic or metal;

Arranging at least one infrared detector at a predetermined position for capturing infrared patterns after the interaction between infrared rays and the graphics unit, preferably, the infrared detector is an infrared camera;

The position of the infrared light source matched with the predetermined position, the position of the infrared light source is used to place the infrared light source, so that the infrared detector captures the corresponding at least one infrared pattern;

Place an infrared light source at the position of the infrared light source, where the infrared light source includes the hand or any other part of the human body;

Complete the anti-counterfeiting identification of anti-counterfeiting patterns by identifying all infrared patterns;

Wherein, when the infrared light source is located at a certain position of the infrared light source, the infrared rays generated by the infrared light source interact with different graphics units to generate infrared patterns of different colors, and/or,

When the infrared light source is located at different infrared light source positions, the infrared rays generated by the infrared light source interact with different graphic units to generate different infrared patterns; in addition, the infrared patterns of different colors can also have differences such as different shapes and different directions at the same time; different The infrared pattern means that the infrared patterns generated by the infrared light sources at different positions are not presented at the same time, and may have differences in shape, direction, color, etc.

In the embodiment of the present invention, by setting the anti-counterfeiting pattern to be composed of different graphic units, the anti-counterfeiting pattern can interact with infrared rays to form infrared patterns of different colors, shapes, and directions. According to the different colors, shapes, and directions of the infrared patterns, it can be completed Anti-counterfeiting identification of anti-counterfeiting patterns. And the infrared ray that human body produces can be used for the identification of the anti-counterfeiting pattern of the present application, therefore can not need artificial light source, thereby can reduce the cost and energy consumption of anti-counterfeiting identification, and operation is simpler; In addition, when using hand as infrared light source, can have Portability, controllability and intelligence; and the controllability and intelligence of the hand can improve the anti-counterfeiting level of anti-counterfeiting technology.

The embodiment of the present invention provides an anti-counterfeiting mechanism based on infrared reflection to prove the application of infrared light sources (taking hands as an example). Invisible patterns (samples) composed of materials with different infrared reflectivities become visible under illumination with the hand as an infrared light source. The difference in the intensity of infrared radiation between the hand and the background environment plays a key role. In the process of anti-counterfeiting identification, infrared detectors capture infrared signals from different areas of the sample. This IR signal consists of infrared light emitted from a specific region of the sample itself (arrows a and a1 in Figure 2) and infrared light from the hand reflected from that region (arrows b and b1 in Figure 2). The difference in the infrared signals of different regions of the sample allows the corresponding anti-counterfeiting pattern to be identified. In the absence of a hand as an infrared light source (as shown in A in Figure 2), the low reflection area (L in Figure 2) and the high reflection area (H in Figure 2) in the sample are in temperature equilibrium with the background , so the infrared signals in different areas are the same, and the infrared detector cannot recognize the anti-counterfeiting pattern. When the hand is used as a light source (as shown by A1 in Figure 2), the infrared radiation of the hand is reflected by all areas, so the infrared signal of the area with high reflectivity is stronger than that of the area with low reflectivity, Therefore, the anti-counterfeit pattern can be recognized by the infrared detector.

Embodiment two

On the basis of Embodiment 1, this embodiment may also include the following:

When arranging the anti-counterfeit pattern in the embodiment of the present invention, the anti-counterfeit pattern may be at least one or more of two-dimensional codes, fingerprints, character strings, characters, numbers or images. In an application scenario, when the anti-counterfeiting pattern is one or more of two-dimensional codes, character strings, characters, numbers, or images, the anti-counterfeiting pattern is composed of graphic units that reflect or absorb infrared rays, and are composed of graphic elements that interfere with infrared rays. The graphic units that act, or are formed by one or more of the graphic units that have a diffracting effect on infrared rays. In another application scenario, when the anti-counterfeiting pattern is a fingerprint, the anti-counterfeiting pattern is only formed by graphic units that reflect infrared rays.

Corresponding to the above-mentioned anti-counterfeiting pattern, in the embodiment of the present invention, when the graphics unit interacts with the infrared rays, the interaction includes at least one or more of reflection, diffraction, interference, absorption and transmission. When the graphics unit interacts with the infrared rays When the interaction is in a variety of different ways, the conditions such as the specific position of the infrared light source will change, so that when performing anti-counterfeiting identification, it is necessary to perform a variety of conditions to change to complete the display of all anti-counterfeiting patterns, that is, the embodiment of the present invention performs multiple The combination of multiple anti-counterfeiting patterns can carry out multiple identifications, thus greatly improving the accuracy of identification and the scope of use. In an application scenario, the graphics unit in the embodiment of the present invention may also include graphics recognized by visible light, Raman, magnetic field, and electric field detection devices.

Embodiment Three

On the basis of the foregoing embodiments, this embodiment may also include the following:

In the embodiment of the present invention, when the anti-counterfeiting identification is performed through the anti-counterfeiting pattern composed of graphic units, the anti-counterfeiting pattern may at least include a graphic unit composed of a polymer or a metal film that reflects or absorbs infrared rays, and a metal that has a diffracting effect on infrared rays. One or more of the pattern units formed by gratings or the pattern units formed by multi-layer film materials that have an interference effect on infrared rays. When the anti-counterfeiting pattern is formed by a variety of graphic units with different action principles (reflection, diffraction, interference, absorption or transmission), multiple identification effects can be achieved (refer to the content of the above graphic units). When the anti-counterfeiting pattern is formed by multiple graphic units with the same working principle, the embodiment of the present invention can also achieve multiple recognition effects by changing the material, period, orientation, duty cycle, thickness and other conditions of the graphic units. In an application scenario, when the anti-counterfeiting pattern includes at least two graphic units made of polymers or metal films that reflect or absorb infrared rays, the materials of different graphic units have different reflectivity or absorptivity, and different Reflectivity or absorptivity will make the infrared pattern captured by the infrared detector have different colors, the principle is:

In the process of infrared thermal imaging, the infrared detector receives the infrared radiation L from the sample (object above absolute zero), which includes both the infrared emission of the sample itself and the infrared light reflected by it. The infrared radiation L of the sample can be calculated by the following formula:

In the formula, ε ₁ is the emissivity of the sample, T ₁ is the temperature of the sample, R ₁ is the reflectance of the sample, T ₂ is the temperature of the reflected object, λ is the wavelength range of infrared light that can be detected by the infrared camera (λ ₁ , λ ₂ ), taking a commonly used infrared camera as an example, λ ₁ = 7.5 μm, λ ₂ = 14 μm, and the embodiment of the present invention assumes that the reflected object is a black body, L _λ (T) is the black body at absolute temperature T and Infrared intensity radiated per unit solid angle at a specific wavelength λ. The above formula includes both the infrared light emitted by the sample itself and the infrared light reflected by the object.

According to Kirchhoff's law, the emissivity of an object is equal to the absorptivity of the object:

ε=α

In the formula, α is the absorption rate of the object.

Among them, the absorptivity (α) of an object is related to the transmittance (t) and reflectivity (R), and its calculation formula is:

α+R+t=1

According to the above formula, if the transmittance of the object is 0, the relationship between emissivity and reflectance can be obtained as:

ε=α=1-R

Combining the formula of infrared radiation L and the formula of absorption rate, it can be obtained that when the transmittance of the object is 0, the formula of infrared radiation L is:

It can be seen from the above formula that, for an anti-counterfeiting pattern, the pattern is composed of parts with different reflectivity (R ₁ ). If the background temperature and the sample (graphic unit) temperature are the same (T1=T2), the formula of infrared radiation L when the transmittance is 0 can be obtained as the rightmost item of the formula is 0, so the reflectance (R ₁ ) is relative to the infrared radiation L will have no effect. That is, when the infrared light source (such as the hand) is not used, the background temperature is the ambient temperature, which is the same as the sample temperature, and the anti-counterfeiting pattern composed of different reflectivities will not be recognized. When using an infrared light source (such as a hand), since the temperature of the hand is often higher than the room temperature (environmental temperature), under this condition, the hand is used as the background, and the background temperature T ₂ is the temperature of the hand, namely The background temperature _T2 is higher than the sample temperature _T1 . At this time, the infrared radiation L of different areas (different graphic units) of the anti-counterfeiting pattern is determined by the reflectivity. The higher the reflectivity, the stronger the infrared radiation and the low reflectivity. The weaker the infrared radiation in the area, the strength of this infrared radiation signal can be recognized by the infrared detector and the infrared pattern with different color changes will be displayed with the difference of false color, that is, the difference in color can achieve the purpose of multiple identification.

In a practical application scenario, anti-counterfeiting patterns can be formed by adjusting the thickness of polydimethylsiloxane (PDMS), and the difference in thickness can realize multi-level color anti-counterfeiting. When infrared light propagates in PDMS, the infrared light will be absorbed by the chemical bonds in PDMS. Thicker PDMS will absorb more infrared light, resulting in less reflected infrared light. When the hand was used as a light source, the thinner PDMS area reflected more infrared light. The intensity of the infrared signal caused by the thickness can be identified by the infrared detector and the change of different colors is displayed by the difference of false color, as shown in D in Figure 3. The infrared signal change caused by this thickness provides the possibility for multi-level color anti-counterfeiting. In the picture D in FIG. 3 , in this embodiment, the thickness of the PDMS of the butterfly part is set to 2.71 microns, the thickness of the flower is set to 0.68 microns, and the thickness of the leaves is set to 54.90 microns. When the hand is used as an infrared light source, different parts appear in different colors.

In addition to multi-level information encryption/decryption, this embodiment can also implement unclonable encryption, for example, unclonable encryption using complex templates, such as fingerprint identification (shown by E in FIG. 3 ). In this example, a thin film of PDMS (7.37 μm in thickness) can be coated on an aluminum substrate by spin coating, and the thumb is lightly pressed on the PDMS, and then fully cured to generate a fingerprint pattern. Local variations in thickness are formed on the PDMS surface. This thickness variation results in a difference in infrared reflectivity, enabling fingerprint recognition. In addition to using fingerprints as templates for unclonable encoding, random patterns with physical unclonable functions can also be integrated into the anti-counterfeiting pattern of the embodiment of the present invention to achieve anti-counterfeiting and information encryption. As shown in F in Figure 3, this random anti-counterfeiting pattern is generated by a spraying process with fast evaporation of solvent.

In another application scenario, when the anti-counterfeiting pattern includes at least two graphic units composed of metal gratings that diffract infrared rays, the metal gratings of different graphic units have different periods, orientations or duty ratios, wherein the different The period or orientation will have different incident angles, that is, infrared light sources at different positions (such as hands) can form infrared patterns corresponding to their positions, and the infrared patterns formed by the diffraction of infrared light sources at different positions can correspond to multiple identifications, which can further To improve the level and reliability of anti-counterfeiting, gratings with different periods or orientations can be combined to form more complex anti-counterfeiting patterns.

As shown in Figure 4, in the actual application scenario, this embodiment selects two metal gratings with mutually perpendicular orientations (the two metal gratings correspond to two graphic units) to form an anti-counterfeiting pattern (as shown in a in Figure 4), This anti-counterfeiting pattern is formed by superimposing the letter "T" and the letter "H", and the metal gratings forming the "T" and "H" are oriented perpendicular to each other. Due to the different orientations of the metal gratings, the hand (infrared light source) needs to be placed in different positions to allow the infrared rays diffracted by a specific graphic unit to be recognized by the infrared detector. When the hand is placed in position 1 (shown in Figure 4 a), the pattern "T" is displayed (shown on the left side of Figure 4 b); when the hand is placed in position 2 (shown in Figure 4 a) , the pattern "H" is displayed (shown on the right side of b in Figure 4). In practical applications, the specific position of the hand can also be used as a key to distribute to designated users. Only when the hand is placed in a specific position can the correct information be identified. A user who does not have a key may be able to recognize the pattern information, but cannot confirm whether the pattern information is correct, thereby improving the level of anti-counterfeiting.

In the embodiment of the present invention, in addition to the effect of the period and orientation of the metal grating on the incident angle, the duty ratio of the metal grating also affects the diffraction intensity, so as to achieve the purpose of multi-level color anti-counterfeiting. The duty cycle is defined as the line width of the grating divided by the period. As the duty cycle changes, the grating diffraction efficiency of infrared light changes accordingly, which in turn affects the intensity of the diffracted infrared light. Under the condition that the duty cycle is less than 60% (period remains unchanged), the diffraction intensity increases with the duty cycle increased by increasing. Based on this principle, as shown in FIG. 5, this embodiment provides three kinds of gratings with the same period but different duty ratios (the three metal gratings G1, G2 and G3 shown in the upper part of FIG. 5), and with these three These gratings form a two-dimensional code pattern (the three metal gratings shown in the lower part of Figure 5, G1, G2, and G3, correspond to the overall pattern of the infrared pattern), and when the hand is placed on the side of the sample as a light source, the infrared camera can identify The two-dimensional code and the different parts of the two-dimensional code have different colors; it is precisely because it has more color differences than the traditional two-dimensional code, resulting in an additional level of anti-counterfeiting compared to the traditional two-dimensional code, which actually constitutes a A 3D code.

In yet another application scenario, when the anti-counterfeiting pattern includes at least two graphic units composed of multilayer film materials having an interference effect on infrared rays, the multilayer film materials of different graphic units have different film thicknesses. Taking a single-layer film as an example, if the thickness of the single-layer film is 1/4 of the wavelength of the incident light, interference and destructive effects will occur between the infrared light reflected by the surface of the single-layer film and the infrared light reflected by the substrate, and the reflection will be suppressed. The intensity of light; if the thickness of the single-layer film is 1/2 of the wavelength of the incident light, interference and constructive effects will occur between the infrared light reflected by the surface of the single-layer film and the infrared light reflected by the substrate, which enhances the intensity of the reflected light , so the captured infrared intensity can be adjusted by adjusting the thickness. Compared with a single-layer film, a multi-layer film can control the interference by adjusting the thickness in a wide band. Films with different thicknesses will form infrared patterns of different colors (different intensities), and the infrared signal changes caused by this thickness provide a ratio Monochrome anti-counterfeiting multi-level color anti-counterfeiting.

Embodiment Four

On the basis of the foregoing embodiments, this embodiment may also include the following:

In the embodiment of the present invention, when the anti-counterfeiting identification of the anti-counterfeiting pattern is completed, all the infrared patterns can be identified to complete the anti-counterfeiting identification of the anti-counterfeiting pattern, including:

One or more of two-dimensional code recognition for infrared patterns, matching infrared patterns with pre-stored reference infrared patterns, or identifying meanings for infrared patterns;

According to the identification and/or matching results, the anti-counterfeiting identification is completed.

In an application scenario, when performing two-dimensional code recognition on an infrared pattern, the two-dimensional code recognition can be completed through identification devices such as mobile phones, and the anti-counterfeiting recognition of the anti-counterfeiting pattern can be completed according to the recognized content. The two-dimensional code in the embodiment of the present invention forms an anti-counterfeiting pattern by spraying PDMS with low infrared reflectivity on the surface of an aluminum sheet with high infrared reflectivity. The method adopted is firstly to dilute PDMS in n-hexane, and then form an anti-counterfeit pattern by spraying. Among them, the infrared reflectance of the aluminum sheet is as high as 99%, while the PDMS film sprayed on the aluminum has a low reflectance due to the infrared absorption of various chemical bonds in PDMS, and the measured average reflectance is 41.2%.

In order to further reflect the anti-counterfeiting effect achieved by using infrared light as the light source, the embodiment of the present invention uses the anti-counterfeiting pattern of the two-dimensional code prepared above as an example to compare with visible light. In the actual application scene, this embodiment uses the FLIR T620 camera to identify the anti-counterfeiting pattern; the resolution of the camera is 640*480, and the power of the LED light used in the visible light mode is 1.2W, in order to keep the power of the hand as an infrared light source Same as the power of LED, first calculate the infrared radiation intensity M _λ (T)dλ of the hand according to the Planck distribution function, the calculation formula is:

In the formula, M _λ (T) is the spectral radiant flux density, h=6.626× ^10-34 J〃s is Planck’s constant, c=2.998×108m〃s ^-1 is the propagation speed of light in vacuum, k =1.38×10 ^-23 J〃K ^-1 is Boltzmann's constant, λ is the wavelength of light, and T is the absolute temperature (K) of the object, which is 310K for the hand. Correspondingly, the infrared radiation intensity of the hand can be obtained by integrating the above formula at wavelengths from 7.5 μm to 14 μm and multiplying by the emissivity 0.98 to obtain the infrared radiation intensity of the hand as ~212 W/m ² . In order to make the radiant power of the hand consistent with that of the LED lamp (1.2W), the radiant area of the hand should be ~60cm ² . However, the area of a human hand is greater than 150 cm ² . Therefore, in this embodiment, a hole of 60 cm ² is formed on the aluminum foil, and then the aluminum foil is wrapped on the hand to carry out the experiment, wherein the position of the hand and the LED light are the same when radiating, and the distance from the hand and the camera to the anti-counterfeiting pattern equal, and the camera is located on the path of the infrared rays radiated by the hand after being reflected by the anti-counterfeit pattern.

In order to quantitatively compare the effects of different recognition methods (visible light and infrared rays), this embodiment converts all photos taken by the camera into grayscale photos and then calculates the root mean square contrast of these photos, and its formula is:

为所有像素点的平均灰度值，在这里本实施例将灰度值归一化到0到1，则计算的均方根对比度的范围为0到0.5。In the formula, I _ij is the gray value of the (i, j)th pixel in the picture, and the size of the picture is M×N,

is the average gray value of all pixels, where the gray value is normalized to 0 to 1 in this embodiment, then the calculated root mean square contrast ranges from 0 to 0.5.

In order to quantify the recognition effect, this embodiment uses a mobile phone to scan two-dimensional codes with different root mean square contrasts. If the information can be scanned, it means that it can be recognized, otherwise it cannot be recognized. According to the critical value of identifiable and unrecognizable, the critical value of root mean square contrast of identifiable pictures can be obtained is 0.042, as shown in Figure 6, part D is the root mean square contrast of pictures that can be recognized, and part U is the root mean square contrast of pictures that cannot be recognized The root mean square contrast of the recognized image.

The embodiment of the present invention adopts the above-mentioned root mean square contrast calculation formula. In the visible light mode, if no LED light source is used, the root mean square contrast corresponding to the picture captured by the camera is 0.020, indicating that the anti-counterfeiting pattern is difficult to identify. When the LED light source is used, the RMS contrast ratio of the pictures captured by the camera increases to 0.035, and the effect is nearly doubled, but the anti-counterfeiting pattern is still difficult to be identified. The reason is that because PDMS itself is transparent, visible light It is difficult to recognize the pattern under these conditions. When the hand is used as an infrared light source, the root mean square contrast of the infrared image obtained increases to 0.251, which is far greater than the identifiable critical value (0.042), that is, the root mean square contrast of the infrared image recognized in this implementation is greater than The critical value of 0.042, so that when infrared light is used as the light source for anti-counterfeiting identification, the image can be clearly identified.

Embodiment five

As shown in Figure 7, this embodiment also provides an anti-counterfeiting system implementing the above method, including:

Anti-counterfeiting pattern 1, which has an infrared pattern for interacting with infrared rays;

Infrared detector 2, which is used to capture the infrared pattern after the interaction between infrared rays and the anti-counterfeiting pattern;

The identification unit is used for identifying the infrared pattern to complete the anti-counterfeiting identification of the anti-counterfeiting pattern.

Embodiment six

An embodiment of the present disclosure provides a non-volatile computer storage medium, and the computer storage medium stores computer-executable instructions, and the computer-executable instructions can execute the method steps in the above embodiments.

It should be noted that the above-mentioned computer-readable medium in the present disclosure may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. A computer readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to, electrical connections with one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable Programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above. In the present disclosure, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In the present disclosure, however, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave carrying computer-readable program code therein. Such propagated data signals may take many forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the foregoing. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can transmit, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device . Program code embodied on a computer readable medium may be transmitted by any appropriate medium, including but not limited to wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

The above-mentioned computer-readable medium may be included in the above-mentioned electronic device, or may exist independently without being incorporated into the electronic device.

Computer program code for carrying out the operations of the present disclosure can be written in one or more programming languages, or combinations thereof, including object-oriented programming languages—such as Java, Smalltalk, C++, and conventional Procedural Programming Language - such as "C" or a similar programming language. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user computer through any kind of network, including a local area network (AN) or a wide area network (WAN), or may be connected to an external computer (such as through an Internet service provider). Internet connection).

The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, program segment, or portion of code that contains one or more logical functions for implementing specified executable instructions. It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by a dedicated hardware-based system that performs the specified functions or operations , or may be implemented by a combination of dedicated hardware and computer instructions.

The units involved in the embodiments described in the present disclosure may be implemented by software or by hardware. Wherein, the name of a unit does not constitute a limitation of the unit itself under certain circumstances.

The preferred embodiments of the present invention have been introduced above, aiming to make the spirit of the present invention clearer and easier to understand, not to limit the present invention, all modifications, replacements and improvements made within the spirit and principles of the present invention , should be included within the scope of protection outlined in the appended claims of the present invention.

Claims (7)

1. An infrared-based anti-counterfeiting method is characterized by comprising the following steps:

constructing an anti-counterfeiting pattern on a substrate, wherein the anti-counterfeiting pattern is composed of at least two graphic units, and the graphic units are used for generating interaction with infrared rays;

arranging at least one infrared detector at a preset position for capturing an infrared pattern generated after the infrared ray interacts with the graphic unit;

the infrared light source position is matched with the preset position and used for placing an infrared light source so that the infrared detector captures at least one corresponding infrared pattern; the infrared light source comprises a hand or any other part of a human body;

placing an infrared light source at the position of the infrared light source;

the anti-counterfeiting identification of the anti-counterfeiting pattern is completed by identifying all the infrared patterns;

the infrared ray generated by the infrared light source interacts with different graphic units to generate different infrared patterns;

the anti-counterfeiting pattern at least comprises a graphic unit formed by a polymer or a metal thin film with reflection or absorption effect on infrared rays, a graphic unit formed by a metal grating with diffraction effect on the infrared rays and a graphic unit formed by a multilayer film material with interference effect on the infrared rays;

at least two pattern units are arranged, wherein the pattern units are composed of metal gratings which have diffraction effect on infrared rays, the metal gratings of different pattern units have different periods or orientations, and the infrared patterns corresponding to the positions of the metal gratings are formed by diffraction of the infrared light sources at different positions;

the anti-counterfeiting identification of the anti-counterfeiting pattern is completed by identifying all the infrared patterns, and the method comprises the following steps:

one or more of two-dimensional code recognition of the infrared pattern, matching of the infrared pattern with a prestored reference infrared pattern or meaning recognition of the infrared pattern;

and finishing anti-counterfeiting identification according to the identification and/or matching result.

2. The method of claim 1, wherein the interaction comprises at least a plurality of reflection, diffraction, interference, absorption, and transmission.

3. The method according to claim 1, wherein when the security device comprises at least two graphic elements formed of a polymer or metal film having an infrared-reflecting or absorbing effect, different materials of the graphic elements have different reflectivities or absorptivities.

4. The method of claim 1, wherein the metal gratings of different ones of the graphics primitives have different duty cycles.

5. The method of claim 1, wherein when the security device comprises at least two graphic elements made of a multilayer film material having an interference effect on infrared rays, the multilayer film materials of different graphic elements have different film thicknesses.

6. The method of claim 1, wherein the security device is at least one of a two-dimensional code, a fingerprint, a character string, a letter, a number, or an image.

7. An anti-counterfeiting system for implementing the method according to any one of claims 1 to 6, comprising:

an anti-counterfeiting pattern having an infrared pattern for interacting with infrared rays;

the infrared detector is used for capturing infrared patterns after the infrared rays interact with the anti-counterfeiting patterns;

and the identification unit is used for identifying the infrared pattern so as to complete the anti-counterfeiting identification of the anti-counterfeiting pattern.

Images