JPH11306311A - Magnetic medium and tag detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent illegal use such as alteration or patching of magnetic data. SOLUTION: A base material 11 which has first and second faces and consists of a dielectric, an inductance formed on at least the first face of the base material 11, capacitors which are formed on first and second faces so as to face each other and form a resonance circuit together with the inductance, and a resonance characteristic change means which is arranged in the resonance circuit and changes the resonance characteristic by a received electromagnetic wave are provided. At the time of receiving an electromagnetic wave, the resonance characteristic of the resonance circuit consisting of the inductance and the capacitors is changed. Consequently, the remaining frequency of a magnetic medium can be surely detected and the validity of the magnetic medium can be surely confirmed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic medium and a tag detecting device.

[0002]

2. Description of the Related Art Conventionally, a magnetic medium, for example, a magnetic card used as a prepaid card has a base material of polyethylene terephthalate and stores money data. Each time a magnetic card is used, the money data is reduced.

[0003] The JIS standard for the magnetic card includes JIS
-X6311 to X314. The magnetic card is formed by sequentially laminating a protective layer, a printing layer, a substrate (PET), a magnetic layer, a concealment layer, a printing layer, and a protective layer from the front side. The dimensions of the magnetic card include
Credit card size such as telephone card (JIS size: 54.0 × 85.6 [mm]) and commuter pass size such as orange card (cybernet standard: 57.5 × 8)
5.0 [mm]), and the magnetic card of the credit card size is mainly used for a distribution system, and the magnetic card of a commuter pass size is mainly used for a transportation system. Also,
The dimensions of the magnetic card include those of other standards, such as a highway card and a card for a pachinko machine. And
The thickness of the base material is mainly 0.188 [mm] and 0.25
[Mm]. When the base material is coated with a magnetic material layer and a printing layer, the thickness of the magnetic card becomes 0.21 each.
[Mm] or about 0.27 [mm]. For example, the thickness of the base material of the telephone card is 0.25 [mm], while the thickness of the base material of the other cards is 0.188 [m].
m].

The physical properties of the magnetic card include tensile strength, impact strength, bending strength, warpage, and peeling.
Release, heat resistance, cold resistance, heat stretchability, chemical immersion (cough) resistance, adhesiveness, moisture resistance, light transmission density, toxicity, durability and the like are specified in detail. Further, regarding the magnetic characteristics of the magnetic card, the magnetic card applies a magnetic coating (coating) to the entire surface of the base material and coats a silver layer or the like thereon, and the magnetic substance itself cannot be visually observed. Therefore, the magnetostatic characteristics that define the characteristics of the magnetic material, or convert an electric signal to magnetic data via a magnetic head,
A conversion characteristic or the like for converting the magnetic data into an electric signal is specified.

[0005] The coercive force in the magnetostatic characteristics is a kind of resistance force of a magnetic material to an external magnetic field.
The higher the value of the coercive force, the stronger the resistance, and the coercive force of credit cards, cash cards, etc. is 650 [Oe].
Whereas the coercive force of the prepaid card is 1
750 [Oe] or 2750 [Oe], so that even if a normal magnet touches the magnetic card, the money data and the like are not broken.

[0006]

However, in the above-described conventional magnetic media, unauthorized use such as rewriting or cutting and pasting of magnetic data may be performed. For example,
Rewriting of magnetic data is performed by using a dedicated magnetic writer. And in the case of a telephone card, only one side is used,
Cutting and pasting can be performed using the magnetic sheet portion on the other surface or another magnetic card.

The present invention provides a magnetic medium and a tag detection device which can solve the problems of the conventional magnetic medium and can prevent unauthorized use such as rewriting and cutting and pasting of magnetic data. The purpose is to:

[0008]

For this purpose, a magnetic medium according to the present invention has a first and a second surface, a base made of a dielectric, and a magnetic medium formed on at least the first surface of the base. And a capacitor formed on the first and second surfaces so as to face each other and forming a resonance circuit with the inductance, and a resonance disposed in the resonance circuit and changing a resonance characteristic by a received electromagnetic wave. Characteristic changing means.

In the tag detecting device of the present invention, an excitation frequency oscillating means for generating an excitation signal at a predetermined frequency;
An electromagnetic wave radiating unit that radiates an electromagnetic wave of the frequency based on an excitation signal generated by the excitation frequency oscillating unit; and a resonance circuit disposed on a magnetic medium based on the electromagnetic wave radiated by the electromagnetic wave radiating unit. And a resonance wave frequency detecting unit for detecting the frequency based on the electromagnetic wave received by the electromagnetic wave receiving unit when the electromagnetic wave is resonated.

[0010] The magnetic medium has a resonance characteristic changing means for changing a resonance characteristic by an electromagnetic wave radiated from the electromagnetic wave radiating means.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view of a magnetic card according to the first embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX of FIG. As shown in the figure, 11 is a base material made of PET as a dielectric, and 15 is a magnetic card as a magnetic medium incorporating a wireless resonance tag (not shown). On the first surface of the base material 11, for example, a conductor having a thickness of, for example, several tens of microns, for example, an aluminum foil (foil) is attached and etched to form spiral coil patterns Cp1 to Cp4, and The coil pattern C
Plates PL1 to PL connected to one ends of p1 to Cp4
4 are formed. Further, plates PL5 to PL8 are formed on the second surface of the base material 11 so as to face the plates PL1 to PL4, respectively.

Then, the coil patterns Cp1 to Cp
4 is connected to the base material 11 through the through holes h1 to h4.
And connected to the plates PL5 to PL8 via first to fourth fuses Fu1 to Fu4 as resonance characteristic changing means, respectively. In the present embodiment, the coil patterns Cp1 to Cp4
Is formed only on the first surface, but may be formed on the first and second surfaces.

FIG. 3 is a diagram showing an equivalent circuit of the magnetic card according to the first embodiment of the present invention. As shown in the figure, the inductances L1 to L4 are coil patterns Cp1
(FIG. 1) formed by Cp4 and capacitors C1
C4 is formed by plates PL1 to PL4 and plates PL5 to PL8 arranged to face each other with the base material 11 therebetween. The inductances L1 to L4, first to fourth fuses Fu1 to Fu4, and capacitors C1 to C4
Are connected in series to form a wireless resonance tag C.
u1 to Cu4 are configured. Then, the wireless resonance tag C
When u1 to Cu4 resonate, resonance currents I1 to I4 flow. Note that a resonance circuit is formed by the inductances L1 to L4 and the capacitors C1 to C4.

FIG. 4 is a diagram showing a tag detecting device according to the first embodiment of the present invention. In the figure, reference numeral 15 denotes a magnetic card having a built-in wireless resonance tag Cu1 (FIG. 3) to Cu4, and reference numeral 23 denotes a tag for reading and writing tag information stored in the magnetic card 15 while being separated from the magnetic card 15. The tag detector 16 exchanges commands with the host device, and controls the excitation frequency oscillation circuit 17 as excitation frequency oscillation means and the resonance frequency detection circuit 22 as resonance frequency detection means. It is.

The excitation frequency oscillating circuit 17 includes a controller 1
6 receives the excitation wave generation signal A from the switches SW1 to SW
4 to selectively operate the oscillators F1 to F4 to generate excitation signals B at frequencies f1 to f4 respectively set based on the conditions of the wireless resonance tags Cu1 to Cu4,
The excitation signal B is sent to the current amplification circuit 18. The current amplifying circuit 18 generates an excitation signal B from the excitation frequency oscillation circuit 17.
Receiving the write / read setting signal C from the control unit 16, amplifying the current of the excitation signal B,
The amplified current, that is, the write exciting wave generation current D is supplied to the exciting antenna coil 19 as the electromagnetic wave radiating means, and the magnetic card 15 emits electromagnetic waves of frequencies f1 to f4.

The detecting antenna coil 20 as an electromagnetic wave receiving means receives the electromagnetic waves of the frequencies f1 to f4 radiated from the magnetic card 15 and detects and detects them, thereby inducing an AC resonance wave detection voltage E. Amplifier circuit 21
Amplifies the resonance wave detection voltage E. The resonance wave frequency detection circuit 22 includes first to fourth bandpass filters BPF1 to BPF4. When the genuine magnetic card 15 is used, the first to fourth bandpass filters BPF1 to BPF4 are used. Receives a detection circuit drive signal F from the control unit 16 and, based on the resonance wave detection voltage E amplified by the voltage amplification circuit 21, sets a frequency set based on each condition of the wireless resonance tags Cu 1 to Cu 4 of the magnetic card 15. A frequency corresponding to f1 to f4 is detected, and a resonance wave detection signal G is sent to the control unit 16.

Further, reference numeral 24 denotes a magnetic head for rewriting and reading magnetic data stored in the magnetic card 15; 25, an electric signal amplifier circuit (AMP) for amplifying an electric signal of the magnetic data; The control unit 16
And a filter for extracting a magnetic data component from the electric signal. Next, a read mode operation for reading tag information stored in the magnetic card 15 in the tag detecting device will be described.

FIG. 5 is a time chart showing the operation of the tag detecting device in the read mode according to the first embodiment of the present invention. FIG. 6 is the operation of the tag detecting device in the read mode according to the first embodiment of the present invention. A first flowchart showing
FIG. 7 is a second flowchart showing the operation in the read mode of the tag detection device according to the first embodiment of the present invention, and FIG.
FIG. 9 is a third flowchart showing the operation of the tag detecting device in the read mode according to the first embodiment of the present invention, and FIG. 9 is the second flowchart showing the operation of the tag detecting device in the read mode according to the first embodiment of the present invention. 4 is a flowchart of FIG.

First, in response to a command from the higher-level device (FIG. 4), the control unit 16 sets the write / read setting signal C to low level and sends it to the current amplifier circuit 18 to set the read mode, and set the read mode current. Make settings. Note that the read setting time t _R
, The write / read setting signal C is set to the high level. Next, the control unit 16 turns on the switch SW1 by turning on the excitation wave generation signal A to be sent to the excitation frequency oscillation circuit 17 for the oscillation maintaining time t1, and sends the excitation signal B having the frequency f1 to the current amplification circuit 18 by the oscillator F1. send. Then, the excitation signal B is amplified by the current amplifying circuit 18, the amplitude is supplied to the excitation antenna coil 19 become write excitation wave generating current D of I _RP, antenna coil 19 is a magnetic card vibration該励15 emits an electromagnetic wave of frequency f1.

In this case, the frequency f1 of the emitted electromagnetic wave
And the wireless resonance tag Cu1 disposed in the magnetic card 15
(FIG. 3) Any one of the frequencies f1 to f4 set to Cu4 matches (in this case, the wireless resonance tag Cu1
And the frequency f1 set to the same. ) And the matching wireless resonance tag Cu1 resonates to generate a resonance current I1,
The resonance current I1 continues to flow until it attenuates for a while even if the radiation of the electromagnetic wave stops. Then, the wireless resonance tags Cu1 to Cu4 generate an AC magnetic field by the resonance current I1, and the detection antenna coil 2 of the tag detector 23
For 0, an electromagnetic wave of frequency f1 is radiated. The oscillation maintaining time t1 is set to a time required for generating a sufficient resonance current I1 in the magnetic card 15 and stabilizing the same.

By the way, the frequency of the radiated electromagnetic wave and the wireless resonance tags Cu1 to Cu
In the case where any one of the frequencies f1 to f4 set to 4 does not match, none of the resonance currents I1 to I4 is generated in each of the wireless resonance tags Cu1 to Cu4. Therefore, the wireless resonance tags Cu1 to Cu4 are connected to the detection antenna coil 20.
Does not emit electromagnetic waves. Then, the oscillation maintaining time t1
Is elapsed, the oscillation by the oscillator F1 is stopped.

Next, the control section 16 turns on the detection circuit drive signal F in order to detect the tag information, and outputs the output of the first band-pass filter BPF1 corresponding to the frequency f1 in the resonance wave frequency detection circuit 22, That is, it is determined whether the resonance wave detection signal G has become a high level. In this case, a waiting time, that is, an interval time t2 is set in order to prevent the electromagnetic wave f1 radiated from the excitation antenna coil 19 from wrapping around the detection antenna coil 20 and erroneously detecting tag information. When the interval time t2 has elapsed, the detection circuit drive signal F
Is set to a high level.

If the resonance wave detection signal G does not become high even after the output delay time t3 set for judging whether the resonance wave detection signal G has become high or not, the wireless communication is performed. It is determined that no resonance current I1 is generated in the resonance tag Cu1. That is, the control unit 16 controls the first fuse F of the wireless resonance tag Cu1.
It is determined that u1 has run out, and the operation moves to the next frequency f2. The resonance wave detection signal G is formed by slicing the resonance wave detection voltage E at a threshold value TH1.

On the other hand, when the resonance wave detection signal G goes to a high level, the detected output may be caused by accidentally generated noise.
With sets 1, initial count value n set by the detection time t4 until n ₀ is the number of times the resonance wave detection signal G to determine whether brought high. The resonance wave detection signal G is set at least once among the set number of times.
Does not become high level, the first fuse F
It is determined that u1 has run out, and the operation moves to the next frequency f2. In addition, when the resonance wave detection signal G has become the high level in all of the set times, the first
It is determined that the fuse Fu1 is not blown, and the operation proceeds to the next frequency f2.

Thereafter, by repeating the same operation for the frequencies f2 to f4, it is possible to determine whether the first to fourth fuses Fu1 to Fu4 are blown, and to detect the tag information. . Next, the flowchart will be described. Step S1 The write / read setting signal C is set to low level to set the read mode. Step S2: The switch SW1 is turned on, and the frequency f1
Start excitation. Step S3: Wait until the oscillation maintaining time t1 elapses. Step S4: The switch SW1 is turned off, and the frequency f1
The excitation of is ended. Step S5: Wait until the interval time t2 elapses. Step S6: It is determined whether or not the output of the first band-pass filter BPF1, that is, whether or not the resonance wave detection signal G has become high level. If the resonance wave detection signal G has become high level, the process proceeds to step S9, and if not, the process proceeds to step S7. Step S7: It is determined whether the output delay time t3 has elapsed. If the output delay time t3 has elapsed, the process proceeds to step 8, and if not, the process returns to step S6. Step S8: It is determined that the first fuse Fu1 is blown, and the process proceeds to step S15. Step S9: Set 1 to the initial count value n. Step S10: Wait for the detection time t4 to elapse. Step S11: It is determined whether the resonance wave detection signal G has become a high level. If the resonance wave detection signal G has become high level, the process proceeds to step S12, and if not, the process proceeds to step S8. Step S12: The initial count value n is incremented. Step S13 The initial count value n determines whether the value n ₀ or more. If the initial count value n is equal to or greater than the value n ₀ , the process proceeds to step S14, and if the initial count value n is smaller than the value n ₀ , the process returns to step S10. Step S14: It is determined that the first fuse Fu1 is not blown, and the process proceeds to step S15. Step S15: The switch SW2 is turned on, and the frequency f
2. Excitation of 2 is started. Step S16: Wait for the oscillation maintaining time t1 to elapse. Step S17: The switch SW2 is turned off and the frequency f
The excitation of 2 is ended. Step S18: Wait until the interval time t2 elapses. Step S19: It is determined whether or not the output of the second band-pass filter BPF2, that is, whether or not the resonance wave detection signal G has become high level. If the resonance wave detection signal G has reached the high level, the process proceeds to step S22, and if not, the process proceeds to step S20. Step S20: It is determined whether or not the output delay time t3 has elapsed. If the output delay time t3 has elapsed, the process proceeds to step 21; otherwise, the process returns to step S19. Step S21: It is determined that the second fuse Fu2 is blown, and the process proceeds to step S28. Step S22: Set 1 to the initial count value n. Step S23: Wait for the detection time t4 to elapse. Step S24: It is determined whether the resonance wave detection signal G has become a high level. If the resonance wave detection signal G has become high level, the process proceeds to step S25, and if not, the process proceeds to step S21. Step S25: The initial count value n is incremented. Step S26 The initial count value n determines whether the value n ₀ or more. If the initial count value n is equal to or greater than the value n ₀ , the process proceeds to step S27. If the initial count value n is smaller than the value n ₀ , the process returns to step S23. Step S27: It is determined that the second fuse Fu2 is not blown, and the process proceeds to step S28. Step S28: The switch SW3 is turned on, and the frequency f
Excitation of 3 starts. Step S29: Wait until the oscillation maintaining time t1 elapses. Step S30: The switch SW3 is turned off and the frequency f
The excitation of 3 is ended. Step S31: Wait until the interval time t2 elapses. Step S32: It is determined whether or not the output of the third band-pass filter BPF3, that is, whether or not the resonance wave detection signal G has become high level. If the resonance wave detection signal G has become high level, the process proceeds to step S35, and if not, the process proceeds to step S33. Step S33: It is determined whether or not the output delay time t3 has elapsed. If the output delay time t3 has elapsed, the process proceeds to step 34, and if not, the process returns to step S32. Step S34: It is determined that the third fuse Fu3 is blown, and the process proceeds to step S41. Step S35: Set 1 to the initial count value n. Step S36: Wait until the detection time t4 elapses. Step S37: to judge whether the resonance wave detection signal G has become high level. If the resonance wave detection signal G has become high level, the process proceeds to step S38, and if not, the process proceeds to step S34. Step S38: The initial count value n is incremented. Step S39 The initial count value n determines whether the value n ₀ or more. When the initial count value n is equal to or greater than the value n ₀ , the process proceeds to step S40, and when the initial count value n is smaller than the value n ₀ , the process returns to step S36. Step S40: It is determined that the third fuse Fu3 is not blown, and the process proceeds to step S41. Step S41: The switch SW4 is turned on, and the frequency f
4. Excitation of 4 is started. Step S42: Wait for the oscillation maintaining time t1 to elapse. Step S43: The switch SW4 is turned off and the frequency f
The excitation of 4 is ended. Step S44: Wait until the interval time t2 elapses. Step S45: It is determined whether or not the output of the fourth band-pass filter BPF4, that is, whether or not the resonance wave detection signal G has become high level. If the resonance wave detection signal G has become high level, the process proceeds to step S48, and if not, the process proceeds to step S46. Step S46: It is determined whether or not the output delay time t3 has elapsed. If the output delay time t3 has elapsed, the process proceeds to step 47, and if not, the process returns to step S45. Step S47: It is determined that the fourth fuse Fu4 is blown. Step S48: Set 1 to the initial count value n. Step S49: Wait until the detection time t4 elapses. Step S50: It is determined whether the resonance wave detection signal G has become a high level. If the resonance wave detection signal G has become high level, the process proceeds to step S51, and if not, the process proceeds to step S47. Step S51: The initial count value n is incremented. Step S52 The initial count value n determines whether the value n ₀ or more. If the initial count value n is equal to or greater than the value n ₀ , the process proceeds to step S53. If the initial count value n is smaller than the value n _{0, the} process returns to step S49. Step S53: It is determined that the fourth fuse Fu4 is not blown.

Next, the operation of the write mode for writing tag information on the magnetic card 15 will be described. FIG.
0 is a time chart showing the operation in the write mode of the tag detection device according to the first embodiment of the present invention, and FIG. 11 shows the operation in the write mode of the tag detection device according to the first embodiment of the present invention. FIG. 12 is a second flowchart showing the operation of the tag detection device in the write mode according to the first embodiment of the present invention, and FIG. 13 is an ID table according to the first embodiment of the present invention. FIG.

First, before executing the writing, it is not known whether the tag information has been written or not.
In order to confirm the setting status of (FIG. 4), the reading mode is set, and each of the first to fourth modes is set by the method described above.
It is determined whether the fuses Fu1 (FIG. 3) to Fu4 are blown. Next, all the first to fourth fuses F
When it is confirmed that u1 to Fu4 are not blown, the control unit 16 writes tag information corresponding to the ID to be set on the magnetic card 15, and the first to fourth fuses Fu1 of the predetermined wireless resonance tags Cu1 to Cu4. To Fu4 to change the resonance characteristics of the wireless resonance tags Cu1 to Cu4.

To this end, the control unit 16 first writes / writes
The read setting signal C is set to a high level and sent to the current amplifying circuit 18 to set the write mode and set the current for the write mode. When the write setting time t _W has elapsed, the write / read setting signal C is set to a low level. Next, the control unit 16
Sets the excitation wave generation signal A sent to the excitation frequency oscillation circuit 17 to the high level only for the oscillation maintaining time t _ON , and sets the switch SWm
(M = 1, 2, 3, 4) and turn on the oscillator Fm (m =
The frequency fm (m = 1, 2,
The excitation signal B of (3) and (4) is sent to the current amplification circuit 18. The excitation signal B is amplified by the current amplifying circuit 18, becomes a write excitation wave generation current D having a current value I _WP required for writing, and is supplied to the excitation antenna coil 19. The coil 19 is driven for an excitation time t _L and emits an electromagnetic wave having a frequency fm to the magnetic card 15.

In this case, the frequency fm of the emitted electromagnetic wave
And the wireless resonance tag Cum disposed in the magnetic card 15
Any of the frequencies fm set to (m = 1, 2, 3, 4)
If they match, the matched wireless resonance tag Cum is shared.
Current value I required for shaking and writing _WTWith frequency fm
A resonance current Im (m = 1, 2, 3, 4) is generated. Soshi
Therefore, the resonance current Im is the resonance time t_F(<T_ON) Just flow
Then, the m-th (m = 1, 2, 3, 4) fuse Fum
(M = 1, 2, 3, 4) is cut off.

In this case, as shown in FIG. 13, which of the m-th fuse Fum is to be blown is determined according to the ID to be set. In FIG. 13, when the resonance current Im having the frequency fm is generated, the value becomes “1”, when the resonance current Im having the frequency fm is not generated, the value becomes “0”, and when the m-th fuse Fum is blown, It becomes "1" and becomes "0" when the mth fuse Fum is not blown.

When the oscillation maintaining time t _ON elapses,
The control unit 16 sets the excitation wave generation signal A to low level, turns off the switch SWm, and stops the oscillation at the frequency fm. In this way, when the writing of the tag information is completed, the control unit 16 sets the read mode again, and sets the read mode.
It is confirmed whether the mth fuse Fum corresponding to D is blown.

As described above, the plurality of wireless resonance tags Cum are formed on the magnetic card 15, the m-th fuse Fum is provided for each of the wireless resonance tags Cum, and the m-th fuse Fum is used as a measure of the remaining number. Tag information can be written by selectively cutting off under predetermined conditions of electromagnetic waves. Therefore, since each wireless resonance tag Cum resonates and the tag information can be detected based on the output of the m-th band-pass filter BPFm, the residual number of the magnetic card 15 can be reliably detected, or the magnetic card 15 can be detected. Or the like can be surely confirmed.

Further, once the m-th fuse Fum is blown (once) and the resonance circuit of the wireless resonance tag Cum is cut off, it is not only impossible to restore it, but also from the appearance, the m-th fuse Fum cannot be restored. It is not possible to determine which of the fuses Fum is blown. Therefore, unauthorized use such as rewriting or cutting and pasting of magnetic data can be prevented.

Regarding the cutting and pasting, when the m-th fuse Fum is blown, the resonance circuit is cut off, so that the frequency fm for resonating the wireless resonance tag Cum cannot be known. Therefore, it is almost impossible to reproduce the constant of the resonance wave frequency detection circuit 22 in the thickness condition of the magnetic card 15 when performing the cut and paste. Can be completely prevented.

Further, the inductances L1 to L4 and the capacitors C1 to C4 can be formed not only by using thin-film aluminum, but also by forming the m-th fuse Fum with a thin-film metal paste or the like. In addition, the thickness of the magnetic card 15 can be kept within a standard range. Moreover, by disposing the wireless resonance tag Cum on the magnetic card 15, the magnetic card 15
The cost is not high.

In this embodiment, the m-th fuse Fum and the resonance circuit are connected in series. However, the m-th fuse Fum and the resonance circuit are connected in parallel and the m-th fuse Fum is connected to the resonance circuit. When the fuse Fum is blown, the frequency of the resonance currents I1 to I4 can be changed. next,
The flowchart will be described. Step S61: The write / read setting signal C is set to the high level to set the write mode. Step S62: Set 1 to the value m. Step S63: The switch SWm is turned on, and the frequency f
Start excitation of m. Step S64: Set 0 at time t. Step S65: Wait until the oscillation maintaining time t1 elapses. Step S66: The switch SWm is turned off and the frequency f
The excitation of m ends. Step S67: 0 is set to time t. Step S68: Wait until the interval time t2 elapses. Step S69: Set the detection circuit drive signal F to high level. Step S70: 0 is set at time t. Step S71: Wait until the output delay time t3 elapses. Step S72: 1 is set to the initial count value n. Step S73: It is determined whether or not the output of the m-th bandpass filter BPFm, that is, whether the resonance wave detection signal G has become high level. If the resonance wave detection signal G has become high level, the process proceeds to step S74; otherwise, the process proceeds to step S78. Step S74: 0 is set at time t. Step S75: Wait until the detection time t4 elapses. Step S76 The initial count value n determines whether the value n ₀ or more. Step S81 If the initial count value n is a value n ₀ or more, if the initial count value n has a value n ₀ is smaller than the flow proceeds to step S77. Step S77: The initial count value n is incremented. Step S78: It is determined that the m-th fuse Fum is blown, and the process proceeds to step S79. Step S79: It is determined whether or not the value m is equal to or larger than the maximum value m ₀ (m ₀ = 4 in the present embodiment). If the value m is equal to or greater than the maximum value m ₀ , the process ends, and if the value m is less than the maximum value m ₀ , the process proceeds to step S80. In step S80, the value m is incremented, and in step S80
Return to 61. Step S81: It is determined that the m-th fuse Fum is not blown. Step S82: It is determined whether or not the mth fuse Fum is blown. If the mth fuse Fum is to be blown, the process proceeds to step S83; otherwise, the process ends. Step S83: The control section 16 executes writing. Step S84: The switch SWm is turned on, and the frequency f
Start excitation of m. Step S85: Set 0 at time t. Step S86: Wait until the oscillation maintaining time t _ON elapses. Step S87: The switch SWm is turned off and the frequency f
m, and the process returns to step S63.

In the present embodiment, the wireless resonance tags Cu1 to Cu4 are arranged on the magnetic card 15, but a seal, a resin plate or the like provided with one or more wireless resonance tags is provided. By attaching a magnetic medium to each package in the distribution system, it is possible to sort the packages, and to attach each product in a store to automate cash registers, manage products, manage inventory, and the like.

In this case, once the tag information is detected,
Since the first to fourth fuses Fu1 to Fu4 are blown,
Tag information is not detected twice. Further, since it is not necessary to form a separate wireless resonance tag each time the frequency is changed, the cost of the magnetic card 15 can be reduced. Next, a second embodiment of the present invention will be described.

FIG. 14 is a plan view of a magnetic card according to the second embodiment of the present invention, and FIG. 15 is a sectional view taken along line YY of FIG. As shown in the figure, 31 is PET as a dielectric
The base material formed by 35 is a wireless resonance tag Cu11.
Is a magnetic card as a magnetic medium in which is embedded. On the first surface of the base material 31, for example, an aluminum foil having a thickness of several tens of microns is attached and etched to form a spiral coil pattern Cp11, and a plate PL11 is provided at one end of the coil pattern Cp11. Connected.

The other end of the coil pattern Cp11 is led out through the through hole h11 onto the second surface of the base material 31, and a plate PL12 is provided on the second surface so as to face the plate PL11. Is done. Further, the plates PL11, PL1 are provided in the through holes h11.
Fuse Fu as a resonance characteristic changing means for connecting the two.
11 is provided.

In this case, since the fuse Fu11 is provided in the through hole h11, it is easy to form the magnetic card 35. Next, a third embodiment of the present invention will be described. FIG. 16 is a plan view of a magnetic card according to the third embodiment of the present invention, FIG. 17 is a sectional view taken along line ZZ of FIG. 16, and FIG. 18 is a first view of a wireless resonance tag according to the third embodiment of the present invention. FIG. 19 is a diagram showing a second equivalent circuit of the wireless resonance tag according to the third embodiment of the present invention, and FIG. 20 is a diagram showing a tag detecting device according to the third embodiment of the present invention. 6 is a time chart illustrating an operation in a writing mode. In addition, about what has the same structure as 1st Embodiment, the description is abbreviate | omitted by attaching the same code | symbol.

As shown in the figure, 41 is P as a dielectric.
The base material formed by ET, 45 is a wireless resonance tag Cu
21 is a magnetic card as a magnetic medium having a built-in 21. On the first surface of the base material 41, for example, a spiral coil pattern Cp11 is formed by bonding and etching aluminum foil having a thickness of several tens of microns,
A plate PL11 is connected to one end of the coil pattern Cp11.

The other end of the coil pattern Cp11 is led out through the through hole h12 onto the second surface of the substrate 41, and the plate PL12 is disposed on the second surface so as to face the plate PL11. Is established. FIG.
As shown in FIG. 8, the inductance L11 is formed by the coil pattern Cp11, and the capacitor C11 is provided on the plate P
It is formed by L11 and PL12. Then, by connecting the inductance L11 and the capacitor C11 in series, a wireless resonance tag Cu as a resonance circuit is formed.
21 are configured.

A hole 41a is formed between the plates PL11 and PL12 in the base material 41.
An insulating material 46 as a resonance characteristic changing means is embedded in a. The insulating material 46 functions as a dielectric for forming the capacitance of the capacitor C11. In addition, plate PL
When the voltage applied between the PL 11 and the PL 12 is equal to or less than the threshold value V1, the insulating material 46 functions as an insulator, and the equivalent circuit of the wireless resonance tag Cu21 is as shown in FIG. When the voltage is higher than the threshold value V1, the insulating material 46 causes dielectric breakdown and becomes conductive, and the equivalent circuit of the wireless resonance tag Cu21 is as shown in FIG. In this case, the capacitor C11 loses the charging function, and both ends are short-circuited. 18 and 19, the equivalent circuit of the wireless resonance tag Cu21 has a resonance current I11.
Flows.

Next, the operation of the write mode for writing tag information on the magnetic card 45 will be described. First, before executing writing, in order to confirm the setting status of the magnetic card 45 for which it is not known whether or not tag information has been written, a reading mode is set and it is determined whether or not the capacitor C11 is short-circuited.

Next, when it is confirmed that the capacitor C11 is not short-circuited, the control unit 16 (FIG. 4) writes tag information to the magnetic card 45, and short-circuits the capacitor C11 of the wireless resonance tag Cu21. Therefore, the control unit 16
Sets the excitation wave generation signal A sent to the excitation frequency oscillation circuit 17 to the high level only for the oscillation maintaining time t _ON,
Is turned on, and the excitation signal B having the frequency f1 is sent to the current amplification circuit 18 by the oscillator F1. Then, the excitation signal B is amplified by the current amplifying circuit 18, becomes a write excitation wave generation current D having a current value I _WP required for writing, and is supplied to the excitation antenna coil 19. Is driven for the excitation time t _L and the magnetic card 4
5 emits an electromagnetic wave of frequency f1. In this case, when the frequency f1 of the radiated electromagnetic wave matches the frequency f1 set in the wireless resonance tag Cu21 disposed in the magnetic card 45, the wireless resonance tag Cu21 resonates, and the current value I Resonant current I1 of frequency f1 having _WT
1 occurs.

Then, under a predetermined condition of the electromagnetic wave, the resonance current I11 flows for the resonance time t _C (<t _ON ), and the plate P
When the voltage applied between L11 and PL12 becomes higher than the threshold value V1, the capacitor C11 is short-circuited, and thereafter, the frequency f1 having the current value I _WT ′ is supplied to the wireless resonance tag Cu21.
Is generated. In addition, the oscillation maintaining time t _ON
Is passed, the control unit 16 sets the excitation wave generation signal A to a low level, turns off the switch SW1, and sets the frequency f
Stop the oscillation of 1.

As described above, the radio resonance tag Cu21 is formed on the magnetic card 45, the capacitor C11 is disposed on the radio resonance tag Cu21, and the capacitor C11 is selectively short-circuited as a measure of the remaining frequency, thereby obtaining the tag information. Can be written. Therefore, the wireless resonance tag Cu21 resonates, and the first band-pass filter BPF
Since the tag information can be detected based on the output of 1, the remaining frequency of the magnetic card 45 can be reliably detected, and the validity of the magnetic card 45 can be surely confirmed.

Further, the capacitor C11 is short-circuited once,
When the resonance circuit of the wireless resonance tag Cu21 is destroyed, it is not only impossible to restore the resonance circuit, but it is impossible to determine the short circuit of the capacitor C11 from the appearance. Therefore, unauthorized use such as rewriting or cutting and pasting of magnetic data can be prevented. Regarding the cutting and pasting, when the capacitor C11 is short-circuited, the resonance circuit is destroyed, so that the frequency at which the wireless resonance tag Cu21 resonates cannot be known. Therefore, it is almost impossible to reproduce the constant of the resonance wave frequency detection circuit 22 in the condition of the thickness of the magnetic card 45 when performing the cutting and pasting. Can be completely prevented.

Further, by attaching a seal, a resin plate or the like provided with the wireless resonance tag Cu21 to each package in the distribution system, sorting of the package or attaching each product in the store to automate the cash register,
When merchandise management, inventory management, or the like is performed, once the tag information is detected, the capacitor C11 is short-circuited, so that the tag information is not detected twice. Further, it is not necessary to form a separate wireless resonance tag each time the frequency is changed, so that the cost of the magnetic card can be reduced.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0052]

As described above in detail, according to the present invention, in a magnetic medium, a base material having first and second surfaces and made of a dielectric, and at least a first base material of the base material. And a capacitor formed opposite to the first and second surfaces and forming a resonance circuit with the inductance, and a resonance characteristic provided by the received electromagnetic wave and received by the resonance circuit. And resonance characteristic changing means for changing the resonance characteristic.

In this case, when the electromagnetic wave is received, the resonance characteristics of the resonance circuit including the inductance and the capacitor are changed. Therefore, the residual number of the magnetic medium can be reliably detected, and the validity of the magnetic medium can be surely confirmed. Further, when the resonance characteristics of the resonance circuit are changed by the resonance characteristics changing means, it is not only impossible to restore the resonance characteristics, but the change in the resonance characteristics cannot be determined from the appearance. Therefore, unauthorized use such as rewriting or cutting and pasting of magnetic data can be prevented.

When the resonance characteristics of the resonance circuit change, the frequency at which the resonance circuit resonates cannot be known. Therefore, it is possible to completely prevent forgery, alteration, and the like from being performed by cutting and pasting. Further, the inductance and the capacitor, for example,
Since the magnetic medium can be formed using thin-film aluminum, the thickness of the magnetic medium can be kept within a standard range. Moreover, arranging the resonance circuit in the magnetic medium does not increase the cost of the magnetic medium.

In addition, by attaching a magnetic medium such as a seal or a resin plate having a resonance circuit to each package in the distribution system, sorting of the package is performed. In performing product management, inventory management, and the like, once tag information is detected, the resonance characteristics of the resonance circuit are changed, so that the tag information is not detected twice. Since it is not necessary to form a separate resonance circuit each time the frequency is changed, the cost of the magnetic medium can be reduced.

In the tag detecting device of the present invention, an excitation frequency oscillating means for generating an excitation signal at a predetermined frequency;
An electromagnetic wave radiating unit that radiates an electromagnetic wave of the frequency based on an excitation signal generated by the excitation frequency oscillating unit; and a resonance circuit disposed on a magnetic medium based on the electromagnetic wave radiated by the electromagnetic wave radiating unit. And a resonance wave frequency detecting unit for detecting the frequency based on the electromagnetic wave received by the electromagnetic wave receiving unit when the electromagnetic wave is resonated.

Further, the magnetic medium has a resonance characteristic changing means for changing resonance characteristics by the electromagnetic wave radiated from the electromagnetic wave radiating means. In this case, when the magnetic medium receives the electromagnetic wave radiated by the electromagnetic wave radiating means, the resonance characteristic of the resonance circuit including the inductance and the capacitor is changed.

Therefore, the residual number of the magnetic medium can be reliably detected, and the validity of the magnetic medium can be surely confirmed. Further, when the resonance characteristics of the resonance circuit are changed by the resonance characteristics changing means, it is not only impossible to restore the resonance characteristics, but the change in the resonance characteristics cannot be determined from the appearance. Therefore, unauthorized use such as rewriting or cutting and pasting of magnetic data can be prevented.

In the case of cutting and pasting, if the resonance characteristics of the resonance circuit change, the frequency at which the resonance circuit resonates cannot be known. Therefore, it is possible to completely prevent forgery, alteration, and the like from being performed by cutting and pasting. Also, by attaching a magnetic medium such as a seal provided with a resonance circuit, a resin plate, etc. to each package in the distribution system, sorting of the package or attaching to each product in the store, automatic cash register, product management, In the case of performing inventory management or the like, once the tag information is detected, the resonance characteristics of the resonance circuit are changed, so that the tag information is not detected twice. Since it is not necessary to form a separate resonance circuit each time the frequency is changed, the cost of the magnetic medium can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a magnetic card according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a diagram showing an equivalent circuit of the magnetic card according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a tag detection device according to the first embodiment of the present invention.

FIG. 5 is a time chart illustrating an operation in a read mode of the tag detection device according to the first embodiment of the present invention.

FIG. 6 is a first flowchart showing the operation of the tag detection device in a read mode according to the first embodiment of the present invention.

FIG. 7 is a second flowchart illustrating the operation of the tag detection device in the read mode according to the first embodiment of the present invention.

FIG. 8 is a third flowchart showing the operation in the read mode of the tag detection device according to the first embodiment of the present invention.

FIG. 9 is a fourth flowchart showing the operation of the tag detection device in the read mode according to the first embodiment of the present invention.

FIG. 10 is a time chart illustrating an operation in a write mode of the tag detection device according to the first embodiment of the present invention.

FIG. 11 is a first flowchart showing an operation in a write mode of the tag detection device according to the first embodiment of the present invention.

FIG. 12 is a second flowchart showing the operation of the tag detection device in the write mode according to the first embodiment of the present invention.

FIG. 13 is a diagram showing an ID table according to the first embodiment of the present invention.

FIG. 14 is a plan view of a magnetic card according to a second embodiment of the present invention.

FIG. 15 is a sectional view taken along line YY of FIG. 14;

FIG. 16 is a plan view of a magnetic card according to a third embodiment of the present invention.

17 is a sectional view taken along the line ZZ in FIG. 16;

FIG. 18 is a diagram illustrating a first equivalent circuit of the wireless resonance tag according to the third embodiment of the present invention.

FIG. 19 is a diagram illustrating a second equivalent circuit of the wireless resonance tag according to the third embodiment of the present invention.

FIG. 20 is a time chart illustrating an operation in a write mode of the tag detection device according to the third embodiment of the present invention.

[Explanation of symbols]

 11, 31, 41 Base material 15, 35, 45 Magnetic card 17 Excitation frequency oscillation circuit 19 Excitation antenna coil 20 Detection antenna coil 22 Resonance wave frequency detection circuit 46 Insulating material B Excitation signal C1 to C4, C11 Capacitor Cu1 to Cu4 , Cu11, Cu21 Wireless resonance tag Fu1 to Fu4 First to fourth fuse Fu11 Fuse L1 to L4 Inductance

Claims (8)

[Claims] 1. A substrate having first and second surfaces and made of a dielectric, (b) an inductance formed on at least a first surface of the substrate, and (c) A capacitor formed on the first and second surfaces so as to face each other and forming a resonance circuit with the inductance; and (d) resonance characteristic changing means disposed in the resonance circuit and changing resonance characteristics by a received electromagnetic wave. And a magnetic medium comprising: 2. The magnetic medium according to claim 1, wherein the resonance characteristic changing means is a fuse connected to the inductance and the capacitor and cut under a predetermined condition of an electromagnetic wave. 3. The magnetic medium according to claim 1, wherein the resonance characteristic changing means is an insulating material that is provided between each plate constituting the capacitor and that breaks down under a predetermined condition of an electromagnetic wave. 4. The magnetic medium according to claim 1, wherein a plurality of said resonance characteristic changing means are provided corresponding to mutually different frequencies. 5. An excitation wave oscillating means for generating an excitation signal at a predetermined frequency, and (b) an electromagnetic wave radiating an electromagnetic wave of the frequency based on the excitation signal generated by the excitation frequency oscillating means. And (c) when a resonance circuit disposed on the magnetic medium resonates based on the electromagnetic wave radiated by the electromagnetic wave radiating means,
Electromagnetic wave receiving means for receiving electromagnetic waves of the frequency,
(D) resonance wave frequency detection means for detecting the frequency based on the electromagnetic wave received by the electromagnetic wave reception means, and (e) the magnetic medium is resonated by the electromagnetic wave radiated from the electromagnetic wave emission means. A tag detection device comprising resonance characteristic changing means for changing characteristics. 6. The tag detection device according to claim 5, wherein said resonance characteristic changing means is a fuse connected to an inductance and a capacitor and cut under a predetermined condition of an electromagnetic wave. 7. The tag detection device according to claim 5, wherein the resonance characteristic changing means is an insulating material that is disposed between each plate constituting the capacitor and breaks down under a predetermined condition of an electromagnetic wave. 8. The tag detecting device according to claim 5, wherein a plurality of said resonance characteristic changing means are provided corresponding to different frequencies.