JP2008090652A - RFID media - Google Patents

Abstract

[PROBLEMS] To easily detect whether an IC chip is damaged.
An IC chip 101 connected to a main antenna 110 for writing and reading information in a non-contact state includes two wirings 120a and 120b, and information is written to and read from the IC chip 101. A sub-antenna 120 having a length that resonates with a radio wave having a frequency for performing the above is connected, and the light-emitting element 103 is connected to the sub-antenna 120. The lengths of the two wirings 120a and 120b constituting the sub-antenna 120 do not resonate with the frequency at which information is written to or read from the IC chip 101.
[Selection] Figure 1

Description

  The present invention relates to an RFID medium having an IC chip that can write and read information in a non-contact state, and more particularly, to a technique for detecting breakage of an IC chip such as disconnection of a circuit part in the IC chip. .

  In recent years, with the progress of the information society, information is recorded on a card, and information management and settlement using the card are performed. Information is recorded on a label or tag attached to a product or the like, and the product or the like is managed using the label or tag.

  In information management using such a card, label, or tag, a contactless IC chip on which information can be written to or read from the card, label, or tag without contact is mounted. IC cards, non-contact type IC labels, or non-contact type IC tags are rapidly spreading due to their excellent convenience.

  In a non-contact type IC card, a non-contact type IC label, and a non-contact type IC tag that can write and read information in a non-contact state, in recent years, in order to reduce the size and ensure a communicable distance, A fine IC chip that performs communication using the IC is increasingly used.

  When such a fine IC chip is used, the communicable distance of the IC chip can be extended by connecting a conductive antenna to the IC chip.

  6A and 6B are diagrams showing an example of a non-contact type IC tag on which an IC chip that performs communication using a microwave band is mounted. FIG. 6A is a top view, and FIG. 6B is a view shown in FIG. It is AA 'sectional drawing.

  In this configuration example, as shown in FIG. 6, an antenna 310 including two wirings 310 a and 310 b formed on a base substrate 302 made of resin, paper, or the like and arranged in series so as to be arranged in series with each other. The IC chip 301 capable of writing and reading information in a non-contact state is mounted so as to be connected to one end of the two wirings 310a and 310b.

  The non-contact type IC tag 300 configured as described above resonates with the radio wave from the information writing / reading device by being brought close to the information writing / reading device (not shown) provided outside. A current flows through the antenna 310, and this current is supplied to the IC chip 301, whereby information is written to the IC chip 301 from the information writing / reading device or information written to the IC chip 301 in a non-contact state. Is read by the information writing / reading device. In this way, in order to write / read information to / from the IC chip 301 by the information writing / reading apparatus, the length of the antenna 310 is set to a frequency for writing / reading information to / from the IC chip 301. It is necessary to set according to the impedance matching between the IC chip 301 and the antenna 302.

  Such a non-contact type IC tag 300 is inspected as to whether the IC chip 301 operates normally in the manufacturing stage. Further, even after manufacturing, it is possible to improve the reliability of the application using the non-contact type IC tag 300 by inspecting whether the IC chip 301 is damaged.

  In such an inspection, when the IC chip 301 is damaged due to disconnection of a circuit portion built in the IC chip 301, information cannot be written or read. However, as described above, in the non-contact type IC tag 300 as shown in FIG. 6, the information depends on the length of the antenna 310 and whether or not the impedance matching between the IC chip 301 and the antenna unit 302 is taken. Cannot be written or read. Therefore, when inspecting whether or not the IC chip 301 is damaged, it is possible to determine whether or not the IC chip 301 is damaged only by writing or reading information using the information writing / reading device. It's hard to say that you can.

Here, Patent Document 1 discloses a non-contact data carrier device provided with an impact detection sensor for detecting an impact applied from the outside. This non-contact type data carrier device is provided with an impact detection sensor having a wiring that is disconnected by an impact, and whether or not an impact has been applied by measuring potentials at both ends of the wiring and storing them in the IC chip. Can be stored.
JP 2002-150249 A

  However, when the impact detection sensor as described above is used, it can be confirmed whether or not an external impact has been applied, but it cannot be recognized whether or not the IC chip is damaged by the impact. Also, when confirming whether or not an impact has been applied, information stored in the IC chip is read out, so that information reading processing for the IC chip is performed, and the IC chip is damaged. It cannot be used for the purpose of detecting that.

  The present invention has been made in view of the problems of the conventional technology as described above, and an object thereof is to provide an RFID medium that can easily detect whether an IC chip is damaged. To do.

In order to achieve the above object, the present invention provides:
An IC chip having a circuit portion capable of writing and / or reading information and a main antenna connected to the IC chip, and a current generated in the main antenna by resonating with a received radio wave In the RFID medium in which information is written and / or read out in a non-contact state with respect to the IC chip by being supplied to the circuit unit,
A sub-antenna composed of first and second wiring portions, one end of which is connected to the IC chip so as to be connected to each other via the circuit portion;
Display means connected to the other ends of the first and second wiring portions, respectively, and driven by being supplied with a current generated in the sub-antenna by resonating with the radio wave;
The length of the first and second wiring portions connected via the circuit portion is a length that resonates with the radio wave, and each length is a length that does not resonate with the radio wave. It is characterized by.

  In the present invention configured as described above, when information is written to or read from the circuit portion built in the IC chip, the main antenna connected to the IC chip resonates with the received radio wave, thereby causing the main circuit to resonate. A current is generated in the antenna, and this current is supplied to the circuit portion, whereby information is written to and read from the IC chip in a non-contact state. At this time, in the sub-antenna composed of the first and second wiring portions connected to the circuit portion of the IC chip, the first wiring portion and the second wiring portion are connected via the circuit portion; Since the length connected through the circuit unit is a length that resonates with the received radio wave, a current due to resonance is generated in the sub-antenna composed of the first and second wiring units. Is supplied to the display means to drive the display means. Here, when the IC chip is damaged, such as the circuit part in the IC chip is disconnected, the first wiring part and the second wiring part constituting the sub antenna are disconnected in the circuit part. Since the lengths of the first and second wiring portions do not resonate with radio waves, no current is generated in the sub-antenna in this state, and the display means is not driven.

  As described above, when the IC chip is not damaged, the display means is driven by the current generated by the resonance with the radio wave received by the sub-antenna, and the circuit part in the IC chip is disconnected. If it is damaged, the display means is not driven by not resonating with the radio wave received by the sub-antenna, so that it is detected whether the IC chip is damaged using this display means.

  As described above, in the present invention, when the IC chip is not damaged, the display means is driven by the current generated by resonating with the radio wave received by the sub-antenna, and the circuit portion in the IC chip is disconnected. If the IC chip is damaged, the display means is not driven by not resonating with the radio wave received by the sub-antenna, so that whether the IC chip is damaged using this display means. It can be easily detected.

  Embodiments of the present invention will be described below with reference to the drawings.

  1A and 1B are diagrams showing an embodiment of an RFID medium according to the present invention, in which FIG. 1A is a top view and FIG. 1B is a cross-sectional view taken along line A-A ′ shown in FIG.

  In this embodiment, as shown in FIG. 1, on a base substrate 102 made of resin, paper, or the like, a main antenna 110 composed of two wirings 110a and 110b, a wiring 120a serving as a first wiring portion, and a second wiring. The IC chip 101 capable of writing and reading information in a non-contact state so as to be connected to the main antenna 110 and the sub antenna 120 is formed. In addition, a light emitting element 103 as a display unit is mounted so as to be connected to the sub-antenna 120.

  One end of each of the two wirings 110a and 110b constituting the main antenna 110 is arranged with a gap between them, and is connected to the IC chip 101 at one end thereof, has a zigzag shape, and extends in a direction away from each other, and the other end They are connected to the conductive regions 111a and 111b, respectively. Thus, since the two wirings 110a and 110b have a zigzag shape, the main antenna 110 is a meander antenna.

  The two wirings 120a and 120b constituting the sub-antenna 120 are arranged at one end together with the wirings 110a and 110b via a gap, and are connected to the IC chip 101 at one end and connected to the light emitting element 103 at the other end. Has been.

  The light emitting element 103 includes an LED that emits light when a current flows, and emits light when a current flowing through the sub-antenna 120 is supplied. Therefore, actually, a rectifier circuit using a diode or the like for rectifying the alternating current flowing through the sub-antenna 120 into a direct current, or a capacitor or coil for boosting the voltage due to the current flowing through the sub-antenna 120 is used. Although a booster circuit is provided between the light emitting element 103 and the sub antenna 120, in this embodiment, illustration and description of those components are omitted for the sake of simplicity.

  The IC chip 101 has a circuit portion (not shown) such as a memory and a control circuit capable of writing and reading information inside, and two connection terminals (not shown) are provided with the circuit portion interposed therebetween. . The wirings 110a and 120a are connected to one of the two connection terminals, and the wirings 110b and 120b are connected to the other connection terminal of the two connection terminals. Thereby, the wiring 110a and the wiring 110b are connected to the IC chip 101 so as to be connected to each other via the circuit section in the IC chip 101, and the wiring 120a and the wiring 120b are connected to the circuit section in the IC chip 101. Are connected to the IC chip 101 so as to be connected to each other.

  Here, the lengths of the wirings 110a and 110b constituting the main antenna 110 and the wirings 120a and 120b constituting the sub antenna 120 will be described.

  FIG. 2 is a diagram for explaining the frequency characteristics of the non-contact type IC tag 100 shown in FIG. 1, and the return loss of the non-contact type IC tag 100 with respect to the frequency used for writing / reading information to / from the IC chip 101. Indicates.

In the non-contact type IC tag 100 shown in FIG. 1, as shown in FIG. 2, the return loss varies depending on the frequency used for writing and reading information. Therefore, at the resonance point of the main antenna 110 where the return loss is the lowest. It is necessary to set the frequency at _a certain peak point A to a frequency fa used for writing and reading information. Here, when the main antenna 110, the length is a half of the wavelength λ obtained from the relative permeability and the relative dielectric constant of the frequency f _a and the base substrate 102 to be used for writing and reading information Thus, it functions as a dipole antenna that resonates at _a frequency at the resonance point, and information can be written to and read from the IC chip 101.

Therefore, the length of the main antenna 110, i.e., the length of the two wires 110a via the circuit portion, 110b is connected to the IC chip 101, the frequency f _a and the base substrate 102 to be used for writing and reading information It is ½ of the wavelength λ obtained from the relative permeability and relative permittivity.

Further, in the wiring 110a, 110b constituting the main antenna 110, the length, determined from the relative permeability and the relative dielectric constant of the frequency f _a and the base substrate 102 to be used for writing and reading information of a wavelength lambda 1 / If it is 4, and functions as a monopole antenna in which the frequency at the resonance point resonates becomes f _a, it is possible to write and read information to the IC chip 101.

Therefore, the wiring 110a, the respective lengths of the 110b, and has a quarter of the wavelength λ obtained from the relative permeability and the relative dielectric constant of the frequency f _a and the base substrate 102 to be used for writing and reading information.

Further, the sub-antenna 120, for those that resonates to a radio wave having a frequency f _a above, its length, i.e., the length of two lines 120a through the circuit of the IC chip 101, 120b is connected is has a half of the wavelength λ obtained from the relative permeability and the relative dielectric constant of the frequency f _a and the base substrate 102 to be used for writing and reading information.

Further, the lengths of the wirings 120a and 120b constituting the sub antenna 120 are different from each other. Therefore, the wiring 120a, the length of 120b are obtained from the relative permeability and the relative dielectric constant of the frequency f _a and the base substrate 102 to be used for writing and reading of the wiring 110a, information as 110b constituting the main antenna 110 It is not ¼ of the wavelength λ.

The non-contact type IC tag 100 configured as described above has _a frequency fa from the information writing / reading device by being brought close to an information writing / reading device (not shown) provided outside. A current flows through the main antenna 110 in resonance with the radio wave, and this current is supplied to the IC chip 101, whereby information is written from the information writing / reading device to the IC chip 101 in a non-contact state, or the IC chip Information written in 101 is read out by an information writing / reading device. Also at this time, also in the sub-antenna 120, current flows resonates to a radio wave having a frequency f _a of the information writing / reading device. This current is supplied to the light emitting element 103, whereby the light emitting element 103 is driven and lit.

  The operation of the light emitting element 103 when the IC chip 101 is damaged due to, for example, disconnection of a circuit part built in the IC chip 101 in the above-described non-contact type IC tag 100 will be described.

  FIG. 3 is a diagram for explaining the operation of the light emitting element 103 when the IC chip 101 is damaged in the non-contact type IC tag 100 shown in FIG. 1. FIG. 3A is a diagram illustrating that the IC chip 101 is not damaged. The figure which shows the connection state of the subantenna 120 in a case, (b) is a figure which shows the connection state of the subantenna 120 when the IC chip 101 is damaged.

When the IC chip 101 is not damaged in the non-contact type IC tag 100 shown in FIG. 1, as shown in FIG. 3A, the wiring 120a and the wiring 120b constituting the sub antenna 120 are connected to each other in the IC chip 101. The sub-antenna 120 connected to each other through the circuit portion and connected to the two wirings 120a and 120b has a length f _a and a base used for writing and reading information as described above. It is ½ of the wavelength λ obtained from the relative permeability and relative permittivity of the substrate 102. Therefore, in this state, when the IC chip 101 is brought close to an information writing / reading device for writing or reading information, the sub-antenna 120 performs writing or reading of information from the information writing / reading device. Therefore, a current flows in resonance with a radio wave having _a frequency f _a , and this current is supplied to the light emitting element 103 so that the light emitting element 103 is turned on.

On the other hand, in the non-contact type IC tag 100 shown in FIG. 1, when the IC chip 101 is damaged due to disconnection of the circuit part built in the IC chip 101, as shown in FIG. The wiring 120 a and the wiring 120 b constituting the sub antenna 120 are disconnected at the circuit portion in the IC chip 101. For this reason, the sub-antenna 120 does not function as a dipole antenna that resonates with the frequency at the resonance point f _a, and no current flows through the sub-antenna 120. Further, two wiring 120a was disconnected, in 120b, the as described above, obtained from the frequency f _a and the base member 102 relative permeability and the relative dielectric constant of use in writing and reading of data wavelength lambda 1/4 since it is not already in, does not function as a monopole antenna in which the frequency at the resonance point resonates becomes f _a. As a result, when the IC chip 101 is damaged due to disconnection of a circuit portion built in the IC chip 101, no current is generated in the sub-antenna 120, and the light emitting element 103 is not lit.

As described above, when the IC chip 101 is not damaged, when the IC chip 101 is brought close to an information writing / reading apparatus for writing or reading information, information writing from the information writing / reading apparatus is performed. The sub-antenna 120 resonates with a radio wave having _a frequency f _a for reading and a current flows through the sub-antenna 120. The light-emitting element 103 is turned on by this current, and the circuit unit in the IC chip 101 is disconnected. When the IC chip 101 is damaged, even if the IC chip 101 is brought close to the information writing / reading device, it is subtracted by radio waves having _a frequency f _a for writing and reading information from the information writing / reading device. Since the antenna 120 does not resonate and no current is supplied to the light emitting element 103 and the light emitting element 103 does not turn on, the IC depends on whether the light emitting element 103 is turned on or not. It is possible to detect whether the chip 101 is damaged.

  Further, as described above, the electromotive force of the light emitting element 103 is caused by the current generated in the sub antenna 120 due to the resonance of the sub antenna 120 with the radio wave from the information writing / reading device. Therefore, it is not necessary to incorporate a power source such as a battery for the non-contact type IC tag 100, and maintenance such as battery exhaustion is not necessary.

Note that in this embodiment, the lengths of the wiring 110a and the wiring 120a, and the wiring 110b and the wiring 120b connected to each other at the connection terminal of the IC chip 101 are the frequencies f _a used for writing and reading information. And the portion obtained by combining the wiring 110a and the wiring 120a even when the IC chip 101 is damaged, when the wavelength λ obtained from the relative permeability and relative permittivity of the base substrate 102 is 1/2. In addition, a current flows in a portion where the wiring 110b and the wiring 120b are combined, and this current may be supplied to the light emitting element 103 to cause the light emitting element 103 to emit light. Therefore, the wiring 110a and a wiring 120a, and the respective length obtained by adding the wiring 110b and the wiring 120b is determined from the frequency f _a and the base member 102 relative permeability and the relative dielectric constant of use in writing and reading information It is necessary that the wavelength λ is not ½. However, in those shown in this embodiment, as described above, the wiring 110a, the length of each of 110b is, relative permeability and relative permittivity of the frequency f _a and the base substrate 102 to be used for writing and reading information rate and has a quarter of the wavelength λ obtained from, and the wiring 120a, the length of each of 120b is, relative permeability and relative permittivity of the frequency f _a and the base substrate 102 to be used for writing and reading information Therefore, the lengths of the wiring 110a and the wiring 120a, and the wiring 110b and the wiring 120b, respectively, are frequencies f _a used for writing and reading information. And λ of the wavelength λ obtained from the relative permeability and relative permittivity of the base substrate 102.

(Other embodiments)
4A and 4B are diagrams showing another embodiment of the RFID medium of the present invention, in which FIG. 4A is a top view and FIG. 4B is a cross-sectional view taken along line AA ′ shown in FIG.

  As shown in FIG. 4, this embodiment is different from that shown in FIG. 1 only in that a rectifier bridge 205 is connected in parallel with the IC chip 201 between two wirings 210a and 210b. .

  Hereinafter, the operation of the light emitting element 203 when the IC chip 201 is damaged in the above-described non-contact type IC tag 200 due to disconnection of a circuit unit built in the IC chip 201 will be described.

  FIG. 5 is a diagram for explaining the operation of the light-emitting element 203 when the IC chip 201 is damaged in the non-contact type IC tag 200 shown in FIG. 4. FIG. 5A is a diagram illustrating that the IC chip 201 is not damaged. The figure which shows the connection state of the subantenna 220 in a case, (b) is a figure which shows the connection state of the subantenna 220 in case the IC chip 201 is damaged.

When the IC chip 201 is not damaged in the non-contact type IC tag 200 shown in FIG. 4, the wiring 220a and the wiring 220b constituting the sub antenna 220 are connected to each other in the IC chip 201 as shown in FIG. and in a state of being connected to each other via the circuit portion, the length of the sub-antenna 220 in which two wires 220a, 220b is connected, the ratio of the frequency f _a and the base substrate 202 to be used for writing and reading information It is ½ of the wavelength λ obtained from the magnetic permeability and relative dielectric constant. Therefore, in this state, when the IC chip 201 is brought close to an information writing / reading device that writes and reads information, the sub-antenna 220 writes and reads information from the information writing / reading device. A current flows by resonating with a radio wave having _a frequency f _a for this purpose, and this current is supplied to the light emitting element 203 so that the light emitting element 203 is turned on.

On the other hand, in the non-contact type IC tag 200 shown in FIG. 4, when the IC chip 201 is damaged due to disconnection of a circuit part built in the IC chip 201, as shown in FIG. Although the wiring 220 a and the wiring 220 b constituting the sub antenna 220 are disconnected at the circuit portion in the IC chip 201, a part of the wirings 210 a and 210 b is connected to the rectification bridge 205. Accordingly, the length of the antenna portion connected to the light emitting element 203 is a length obtained by adding the sub-antenna 220 including the two wirings 220a and 220b, a part of the wirings 210a and 210b, and the rectifying bridge 205. Therefore, it does not have a length that resonates with a radio wave having _a frequency f _a for performing writing and reading of information from the information writing / reading device, and a current caused by resonance is generated in the antenna portion connected to the light emitting element 203. The light does not flow, the current is not supplied to the light emitting element 203, and the light emitting element 203 is not lit. At this time, the configuration of the antenna unit connected to the light emitting element 203 is changed from only the sub-antenna 220 to one composed of the sub-antenna 220, a part of the wirings 210a and 210b, and the rectifier bridge 205. Even when the impedance changes, the antenna unit does not resonate with radio waves having _a frequency fa for writing / reading information from the information writing / reading device.

  In the above-described two embodiments, the main antennas 110 and 210 have been described using a meander antenna as an example. However, even in the case of a general dipole antenna whose wiring is linear, this The invention can be applied. Further, it may be a monopole antenna consisting of one wiring instead of two wirings.

  In the above-described two embodiments, the light emitting elements 103 and 203 such as LEDs have been described as an example of display means. However, the present invention is not limited to this and is driven by the current flowing through the sub-antennas 120 and 220. It is applicable if it does. For example, the light emitting elements 103 and 203 do not simply emit light by the supplied current, but various devices such as a device that displays preset information and a device that generates sound can be applied. .

  In the above-described two embodiments, the non-contact type IC tags 100 and 200 have been described as examples of the RFID medium. However, it goes without saying that the present invention can also be applied to non-contact type IC cards, non-contact type IC labels, and the like. Yes.

It is a figure which shows one Embodiment of the RFID media of this invention, (a) is a top view, (b) is A-A 'sectional drawing shown to (a). It is a figure for demonstrating the frequency characteristic of the non-contact-type IC tag shown in FIG. FIG. 2 is a diagram for explaining the operation of a light emitting element when an IC chip is damaged in the non-contact type IC tag shown in FIG. 1, and (a) shows a connection state of sub-antennas when the IC chip is not damaged. FIG. 5B is a diagram showing a connection state of the sub antenna when the IC chip is damaged. It is a figure which shows other embodiment of the RFID medium of this invention, (a) is a top view, (b) is A-A 'sectional drawing shown to (a). FIG. 5 is a diagram for explaining the operation of the light emitting element when the IC chip is damaged in the non-contact type IC tag shown in FIG. 4, and (a) shows the connection state of the sub antenna when the IC chip is not damaged. FIG. 5B is a diagram showing a connection state of the sub antenna when the IC chip is damaged. It is a figure which shows an example of the non-contact-type IC tag with which the IC chip which communicates using a microwave band is mounted, (a) is a top view, (b) is AA 'shown to (a). It is sectional drawing.

Explanation of symbols

100, 200 Non-contact type IC tag 101, 201 IC chip 102, 202 Base substrate 103, 203 Light emitting element 110, 210 Main antenna 110a, 110b, 120a, 120b, 210a, 210b, 220a, 220b Wiring 111a, 111b Conductive region 120, 220 Sub antenna 205 Rectifier bridge

Claims (1)

An IC chip having a circuit portion capable of writing and / or reading information and a main antenna connected to the IC chip, and a current generated in the main antenna by resonating with a received radio wave In the RFID medium in which information is written and / or read out in a non-contact state with respect to the IC chip by being supplied to the circuit unit,
A sub-antenna composed of first and second wiring portions, one end of which is connected to the IC chip so as to be connected to each other via the circuit portion;
Display means connected to the other ends of the first and second wiring portions, respectively, and driven by being supplied with a current generated in the sub-antenna by resonating with the radio wave;
The length of the first and second wiring portions connected via the circuit portion is a length that resonates with the radio wave, and each length is a length that does not resonate with the radio wave. RFID media characterized by

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