JPH03258595A - Card, card identification and card identification device - Google Patents

Abstract

PURPOSE:To make forgery of a card difficult by providing a fluorescent ink layer and an infrared absorbing ink layer side by side on the surface of a card substrate in such a manner that these layers do not become overlapped and also a concealing layer which allows passage of the wavelengths of exciting beam and fluorescence and absorbs part of a visible light. CONSTITUTION:A fluorescent ink which contains a fluorescent material, the wavelengths of exciting beam and fluorescence of which are present in an infrared range, and an infrared absorbing ink which absorbs a light of fluorescent wavelength are provided side by side at least on one surface of a card substrate 2 in such a manner that these ink layers are not overlapped. In addition, a concealing layer 5 which allows passage of said both wavelengths and absorbs a part of a visible light is provided on the surface of the card substrate 2. After that, the card 1 is irradiated with a light 9 having a wavelength which excites a fluorescent ink and a light 10 which generates a fluorescent wavelength. Then the fluorescence from the card 1 and the reflecting light 11 which causes a subsequent absorption of the fluorescent wavelength are received by a light-reciving element 8 which limits the fluorescent wavelength to a spectral sensitivity range. Consequently, a signal waveform with a positive and a negative peak is detected and it is checked whether an output from the detected signal waveform is present or whether a forged card is present through comparison with a received light pattern setting value or a reference pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a card such as a credit card or a prepaid card provided with counterfeit prevention means, a card identification method, and a card identification device.

[Conventional technology]

Conventionally, various methods have been proposed for applying counterfeit prevention means to cards such as Tallaire cards and prepaid cards, which are often used as payment means in place of cash, and for identifying whether or not these cards are counterfeit. ing.

For example, a method for preventing forgery or identifying a mark or barcode that is optically readable in the visible light range on a card such as a magnetic card, and then optically reading it to identify whether or not it is a counterfeit. In order to further increase the effectiveness of the card, the marks and barcodes are printed using ink that absorbs infrared light in the infrared region, and the marks and barcodes are hidden on the top surface with ink that transmits infrared rays, making them invisible to the naked eye. and scan that barcode on the infrared vA9M
A method has been proposed in which the presence or absence of counterfeiting is determined by optical reading in the field.

[Problem to be solved by the invention]

According to the latter technique mentioned above, even if it is not visible to the naked eye,
By scanning a card using an existing infrared reflective photocoupler, marks and barcodes for counterfeit prevention or identification can be easily found. Infrared absorbing materials not only can be easily reproduced using carbon-based materials, but also infrared-reflecting photocouplers and carbon-based materials are easily available, so they have the problem of being easily counterfeited.

Furthermore, since the obscuring ink itself has some infrared absorption capability, it is necessary to use a mark or barcode substrate with good infrared reflection to improve the optical reflection contrast and enable reliable detection. There is a problem in that highly reliable detection cannot be performed unless a suitable material is used.

The present invention has been made in view of the above problems, and its purpose is to generate complex optical signals having positive and negative peaks by using a combination of fluorescent ink and infrared absorbing ink that absorbs fluorescent wavelengths. To provide a card with a new configuration that makes it extremely difficult to counterfeit a card that is the same as a genuine card, and enables highly reliable detection.

It is also an object of the present invention to enable the detection of complex identification signals having positive and negative peaks formed by fluorescence and reflected light with absorption of fluorescence wavelengths. To provide a new card identification method which makes it possible to detect a mark etc. on a card only after the following conditions are satisfied, thereby making it difficult to read the mark and, by extension, making it extremely difficult to forge a card.

Furthermore, it is an object of the present invention to provide a card identification device capable of receiving fluorescence from a card and reflected light accompanied by absorption of the fluorescence wavelength by a single light-receiving element, thereby reducing the cost of the device. is to provide.

[Means to solve the problem]

In order to achieve the above object, the present invention uses a fluorescent ink containing a fluorescent material whose excitation light wavelength and fluorescent wavelength are both in the infrared region, and an infrared absorbing ink that absorbs the fluorescent wavelength.
They are arranged side by side on at least one side of the card base material or in a barcode-like pattern so as not to overlap each other, and both of the wavelengths mentioned above can be transmitted through the card base material surface, so that visible light is unified. The point is that the card is constructed by providing a hidden layer that absorbs some of the energy.

The present invention also provides a method for irradiating the card configured as described above with light that excites fluorescent ink and light having a fluorescent wavelength,
Fluorescence from the card and reflected light with absorption of fluorescence wavelength,
The light is received by a light-receiving element that has the fluorescence wavelength within its spectral sensitivity,
By detecting the presence or absence of fluorescent light and reflected light with absorption of fluorescent wavelengths, or by comparing the received light pattern with a set value or a reference pattern, a card with a confirmed match is identified as a genuine card. be.

Further, the present invention is characterized in that a light source that generates a wavelength that excites fluorescent ink and a light source that generates a fluorescent wavelength are arranged so that they can irradiate the card surface configured as described above. The present invention is configured to include a single light-receiving element that has a wavelength within the spectral sensitivity and is arranged so as to be able to receive both fluorescence and reflected light with absorption of the fluorescence wavelength.

[Effect]

A fluorescent ink containing a fluorescent substance whose excitation light wavelength and fluorescent wavelength are both in the infrared region and an infrared absorbing ink that absorbs light at the fluorescent wavelength are placed on at least one side of the card base material so that they do not overlap each other. The excitation light of the fluorescent ink and the light that generates the fluorescent wavelength are irradiated onto the card, which is placed side by side on the surface of the fluorescent ink and has a concealing layer that allows both wavelengths to pass through and absorbs visible light. Generates a complex optical signal consisting of reflected light accompanied by absorption of optical wavelengths.

In addition, the card is irradiated with light having a wavelength that excites the fluorescent ink and light that generates a fluorescent wavelength, and the fluorescent light from the card and the reflected light that absorbs the fluorescent wavelength are combined to bring the fluorescent wavelength within the spectral sensitivity. A signal waveform with positive and negative peaks is detected by the light receiving element, and the presence or absence of the output or the light reception pattern is compared with a set value or a reference pattern, and based on the presence or absence of a match, it is determined whether or not the card is counterfeit. .

Furthermore, the card surface is irradiated with light from a light source with a wavelength that excites the phosphor and a light source that generates a fluorescence wavelength, and the fluorescence and the reflected light with absorption of the fluorescence wavelength are combined into a single light source that is sensitive to the fluorescence wavelength. The light is received by a light receiving element.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a card, a card identification method, and a card identification device according to the present invention will be sequentially described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the card of the present invention, in which an excitation wavelength of 80
0nm, the fluorescence wavelength is 980nm, both wavelengths are in the infrared region, and as shown in Figure 6, when the reflectance of the white background of the original is 100%, the reflectance is approximately 107% at the wavelength of 980nm. 1, i (Ndo,
q Ybo, +) PtO barcodes 4 formed using infrared absorbing ink that absorbs Further, in the same way, a barcode 4 made of infrared absorbing ink, a barcode 3.3 made of fluorescent ink, and a barcode 4 made of infrared absorbing ink are arranged side by side. Then, on the card base material 2 provided with these barcodes 3.4.4.3.3.4,
800 nm excitation wavelength and 98 nm as shown in FIG.
A concealing ink that has spectral properties that allow it to transmit both wavelengths of 0 nm fluorescent light and partially absorb visible light, as well as exhibiting opacity that makes barcodes 3.4... invisible to the naked eye. A concealing layer 5 is provided by (Fig. 2),
This constitutes card 1.

It goes without saying that the fluorescent ink and the infrared absorbing ink described above can be placed side by side so as to be in contact with each other, and the order in which the fluorescent ink and the infrared absorbing ink are placed is arbitrary.

Further, the arrangement of the barcodes is not limited to the barcodes arranged side by side in the area shown in the above embodiment, but fluorescent ink and infrared absorbing ink may be arranged side by side in a staggered manner on the card base material 2. Of course, it is also possible to form.

FIG. 2 shows an example of an apparatus for carrying out the card identification method of the present invention, and as shown in the spectral characteristic diagram of FIG. Alternatively, a light emitting element 6 such as a laser diode and a light emitting element 7 that generates light with a fluorescence wavelength of 980 nm from fluorescent ink as shown in the spectral characteristic diagram of FIG. 10 are arranged side by side in the same area l of the card. In order to sequentially irradiate the barcodes, the irradiation angle with respect to the card 1 is set to be at least 90 degrees or less relative to the surface of the cart. In addition, as shown in the spectral characteristic diagram of FIG. It is arranged at a light receiving angle position of 90 degrees with respect to the surface of the card 1 so as to be able to receive both reflected light accompanied by absorption of the fluorescent wavelength by the barcode 4.

Note that in order to prevent the light emitting element 6.7 and the light receiving element 8 from optically interfering with each other, the excitation wavelength of the fluorescent ink is cut on the side of the light receiving element 8, but the fluorescent wavelength is allowed to pass through. A filter or a filter that allows the excitation wavelength of the fluorescent ink to pass through the light-emitting element 6 side, but a filter that cuts the fluorescent wavelength and a filter that allows only the fluorescent wavelength to pass through the light-emitting element 7 side is provided to improve detection accuracy. In this embodiment, although not shown, an InP (indium phosphide) filter having the former characteristic is provided as a filter on the light receiving element 8 side. is suitable.

Next, to explain the effect of the above embodiment, the part 1 is transported in the direction of the arrow 12 by a transport device (not shown), and the excitation light 9 of 800 nm emitted from the light emitting element 6 and the light emitted from the light emitting element 7 are transmitted. When the light 10 with a fluorescence wavelength of 980 nm is irradiated from the left side of the figure on the same area of the card 1, the card 1 starts scanning and the barcodes 3, 4 are sequentially scanned.
．． 4.3.3.4 is scanned, and the light 11 from the card 1 is incident on the light receiving element 8. During this period, until the time t1 when the leftmost barcode 3 is irradiated from the left side of the card 1, the light receiving element 8 receives the reflected light from the card 1 and outputs the level voltage vO. Barcode 3
As shown in FIG. 3, the fluorescent light has a positive peak with respect to the level voltage vO, and at time t2, the fluorescence wavelength is absorbed by the barcode 4, and the reflection has a negative peak with respect to the level voltage VO. Light is received. Similarly, from time t3 to time t5, light 11 having a negative peak, then two positive peaks, and then a negative peak is received and detected by the light receiving element 8. Then, the signal waveform detected by the light-receiving element 8 is inputted manually to a discrimination circuit (not shown in Figure 2), which detects the presence or absence of positive and negative peak values and identifies it as a legitimate card, or the card is identified as a genuine card as shown in Figure 3. By comparing the positive set value VH and the negative set value VL, and cutting the amplitude exceeding these values, as shown in Figs. 4 and 5, positive pulse patterns P1, Pl, etc. and negative pulse patterns are generated. Detect P2, P2, etc., compare the amplitudes VO, VH of this positive pulse pattern with the corresponding reference setting values, and compare the amplitudes VO, VL of the negative pulse pattern with the corresponding reference settings. or these positive and negative pulse patterns and the corresponding reference pattern, and when a match is detected, the card is identified as a regular card.

Note that Li(Ndo, q Ybo, +)PtO+, which was explained in the above example, as a fluorescent material contained in the ink
Needless to say, the present invention is not limited to the fluorescent material ``g'', and may be any fluorescent material having different spectral characteristics for both the excitation light wavelength and the fluorescence wavelength.

〔Effect of the invention〕

As described above, according to the present invention, a fluorescent ink containing a phosphor whose excitation light wavelength and a fluorescent wavelength are both in the infrared region, and an infrared absorbing ink that absorbs light at the fluorescent wavelength,
They are arranged side by side on at least one side of the card base material so that they do not overlap each other or in a barcode-like pattern, and both of the wavelengths mentioned above can be transmitted through the card base material surface, so that visible light can be transmitted. Since the card is constructed with a concealing layer that partially absorbs the light, it is difficult to counterfeit the card.
In addition to making it possible to generate a complex optical signal with a negative peak, it is recognized that fluorescent ink and infrared absorbing ink that absorbs the fluorescent wavelength are installed side by side on the card, and the excitation light and fluorescent wavelength of the fluorescent material It is possible to counterfeit a card that is the same as a genuine card unless one is aware that the card is irradiated with light that generates a It will be extremely difficult.

Furthermore, since the fluorescent material forming the fluorescent ink is more difficult to reproduce and obtain than carbon-based materials, it becomes even more difficult to counterfeit cards.

Further, according to the present invention, the card configured as described above is irradiated with light that excites the fluorescent ink and light having a fluorescent wavelength, and the fluorescent light from the card and the reflected light accompanied by absorption are analyzed by spectroscopy to determine the fluorescent wavelength. The light is received by a light-receiving element within the sensitivity range, and the presence or absence of fluorescence and reflected light with absorption of the fluorescence wavelength is compared, and the light reception pattern is compared with the set value or reference pattern, and a card that is confirmed to match is recognized as a genuine card. G to identify
With this configuration, decoding a card requires the detection of a complex signal waveform with positive and negative peaks, and unless this is clarified, it will become even more difficult to decode a legitimate card, and it will also cause damage to the card. A point where fluorescent ink and an infrared absorbing ink that absorbs fluorescent wavelengths are arranged side by side, a point illuminated by light having an excitation wavelength of the fluorescent ink and a light having a fluorescent wavelength, and a point where fluorescent ink and infrared absorbing ink that absorbs fluorescent wavelengths are arranged side by side, and the fluorescent light from the card and the fluorescent wavelength It is possible to provide an identification method that makes it impossible to decipher a card unless it satisfies all the requirements of the identification method by receiving reflected light accompanied by absorption of the card. Therefore, it is possible to further ensure the prevention of counterfeiting of genuine cards, and it is possible to further improve the security against counterfeiting of cards.

Furthermore, since optics in the infrared region is used, signals can be detected with a high degree of reliability regardless of dirt on the surface of the card.

Further, according to the present invention, a light source having a wavelength that excites fluorescent ink and a light source that emits fluorescence wavelength are arranged so as to be able to irradiate the card surface configured as described above, and the fluorescence wavelength is In addition, the single light-receiving element is arranged so that it can receive both the fluorescence from the card and the reflected light with absorption of the fluorescence wavelength, so only one light-receiving element is required. Therefore, it is possible to reduce the cost of the device.

[Brief explanation of drawings]

FIG. 1 is a top view of an embodiment of the card of the present invention, FIG. 2 is a diagram showing the configuration of an apparatus for carrying out the identification method of the present invention, taken along section line A-A in FIG. 1, and FIG. The figure shows the waveform of signal 6 detected by the light receiving element of the device shown in Fig. 2, and Fig. 4 shows the signal waveform and set value V shown in Fig. 3.
Figure 5 is a pulse waveform diagram obtained by comparison with H.
A pulse waveform diagram obtained by comparing the signal waveform shown in the figure with the set value VL, Figure 6 is a spectral characteristic diagram of the fluorescent ink applied to the present invention, and Figure 7 is a diagram of the fluorescence wavelength absorption applied to the present invention. 8 is a spectral characteristic diagram of the hiding layer applied to the present invention, FIG. 9 is a spectral characteristic diagram of the light emitting element 6 applied to the present invention, and FIG. 10 is a spectral characteristic diagram of the light emitting element 7 applied to the present invention.
Similarly, FIG. 11 is a spectral characteristic diagram showing the radiation sensitivity of the light receiving element. L... Card, 2... Card base material, 3... Barcode formed with fluorescent ink, 4... Infrared absorbing ink that absorbs fluorescent wavelengths, 5... Hiding layer, 6... Exciting fluorescent ink. 7. A light emitting element that emits light at a fluorescent wavelength; 8. A light receiving element that receives a fluorescent light wavelength; 9. Excitation light;
10...Light having a fluorescence wavelength, 11...Reflected light with fluorescence and absorption of the fluorescence wavelength, :8R HR 40-fold diagonal hshi~4>No(2)埒pノ(n4Wtoto) Sa+'＞#lbl, ≦Fraud ζ case unlength Figure 8 Ha unlength Figure 10 Figure 11 (A/W)

Claims (4)

[Claims] (1) A fluorescent ink containing a fluorescent material whose excitation light wavelength and fluorescent wavelength are both in the infrared region and an infrared absorbing ink that absorbs light of the fluorescent wavelength are placed on a card so that they do not overlap each other. A card characterized in that a concealing layer is provided on at least one surface of a base material, and a concealing layer is provided on the surface of the card base material, which allows transmission of both wavelengths and absorbs a portion of visible light. (2) The card according to claim (1), wherein the fluorescent ink and the infrared absorbing ink are arranged side by side in a barcode-like pattern. (3) Fluorescent ink containing a phosphor whose excitation light wavelength and fluorescence wavelength are both in the infrared region and an infrared absorbing ink that absorbs light of the fluorescent wavelength are placed on the card base material so that they do not overlap each other. Light that excites the fluorescent ink and light that has a fluorescent wavelength are irradiated onto a card that is provided with a concealing layer that is arranged in parallel on at least one surface and that allows both of the wavelengths to pass through the card base material surface. , the fluorescence from the card and the reflected light with absorption of the fluorescence wavelength are received by a light receiving element having the fluorescence wavelength within the spectral sensitivity, and the presence or absence of the fluorescence and reflected light is detected, or the light reception pattern and setting value thereof. , or a card identification method characterized by comparing the card with a reference pattern and determining a card that matches the card as a genuine card. (4) A fluorescent ink containing a fluorescent material whose excitation light wavelength and fluorescent wavelength are both in the infrared region and an infrared absorbing ink that absorbs light of the fluorescent wavelength are placed on a card so that they do not overlap each other. A card identification device for reading and identifying a card, which is arranged in parallel on at least one surface of a base material, and is provided with a concealing layer that allows both of the wavelengths to pass through the card base material surface and absorbs a portion of visible light, A light source that emits light at the excitation wavelength of the fluorescent ink and a light source that emits light at the fluorescent wavelength are arranged so as to be able to irradiate the card surface. A card identification device comprising a single light-receiving element arranged so as to be able to receive both fluorescent light from the ink and reflected light with absorption of the fluorescent light wavelength by the infrared absorbing ink.