WO2007046443A1

WO2007046443A1 - Rfid tag

Info

Publication number: WO2007046443A1
Application number: PCT/JP2006/320780
Authority: WO
Inventors: Hiroshi Fujii; Takafumi Kimura
Original assignee: Omron Corporation
Priority date: 2005-10-18
Filing date: 2006-10-18
Publication date: 2007-04-26
Also published as: JP2007114873A

Abstract

As a switch section (6) for short-circuiting a conducting wire between an antenna (2) and an IC chip (3) or permitting currents to be carried in the conducting wire, a movable contact (61) is arranged to be opened and closed, for connecting in parallel a pair of connecting terminals (62a, 62b) arranged on end line sections (22) on the both sides of the antenna (2). When a RFID tag (1) is attached to an object (10), the switch section (6) opens and permits currents to be carried in the conducting wire of the antenna (2) to a power feeding section (23) and the IC chip (3) to operate. When the RFID tag (1) is removed from the object (10), the switch section (6) closes and short-circuits the conducting wire of the antenna (2) to the power feeding section (23) and disables operation of the IC chip (3) to prohibit data writing/reading.

Description

RFID tag

Technical field

The present invention relates to an RFID tag used in fields such as sales distribution and distribution.

Background art

[0002] In recent years, systems using RFID tags have been constructed mainly in fields such as sales and distribution. In this system, data can be read and written wirelessly from / to an RFID tag attached to an object by communicating between the RFID tag and an external reader / writer using electromagnetic waves or radio waves. In addition, RFID tags have the advantage of being able to rewrite data once written compared to tags that have been printed with barcodes that have been used in the past. However, while RFID tags have the advantage of being able to read and write large amounts of data wirelessly as described above, they also have the following problems.

[0003] For example, in a mail-order business, there may be a case where a customer at a delivery destination shows an actual product and purchases it if he / she likes it. If there is a return in this case, the delivery operator attaches an RFID tag to the returned product, writes data such as the delivery destination, date and time, reason for return, etc., takes it back to the store, and manages the return. At this time, the delivery worker has an unused RFID tag along with the product to be delivered, and when receiving a return, the RFID is attached to a powerful return product that will write data using a non-ready reader / writer on site. If you intend to write data to a tag, it may be accidentally written to another unused tag, and data matching cannot be ensured, which hinders management. Therefore, if there is a function that can not write data to the RFID tag before it is attached to the product! /, The human error as described above can be prevented in advance, which is convenient.

[0004] On the other hand, if data related to returns is written on an RFID tag and attached to a product at the same return management site, the reason why the product was returned by reading the tag is shown. It can be understood and used for subsequent sales strategies. However, In the process of writing other products, there may be a human error that mistakenly overwrites the already written RFID tag with data and erases the original data. Therefore, contrary to the above example, it is also required to have a function that prevents data from being written to the RFID tag after it is attached to the product.

[0005] Note that the following patent document discloses a technique in which a label-like data carrier that can be affixed to a product cannot be reused when the product power is peeled off after the affixing. The specific content of the technology is that the antenna and the internal components that also have IC chip strength are sandwiched between the first adhesive layer and the second adhesive layer, and then attached to the product via the second adhesive layer. If an attempt is made to remove the data carrier from the product, the antenna of the internal parts will be damaged and communication will be impossible. However, this technology is effective in preventing the act of exchanging a genuine product with a data carrier attached to an unauthorized product, but it can only be used once, so it can be repeatedly attached to and removed from the product as described above. Is not suitable.

[0006] Patent Document 1: JP 2000-48147 A

Disclosure of the invention

Problems to be solved by the invention

[0007] The present invention has been made to solve the above-described problems, and the object of the present invention is to limit the function of the RFID tag before or after being attached to a product. No The purpose is to provide an RFID tag that can prevent artificial mistakes such as accidentally writing data to the RFID tag.

Means for solving the problem

[0008] In order to achieve the above object, the RFID tag of the present invention is an RFID tag having an unrestricted state and a restricted state with a function restriction without any function restriction. And switching means for switching the state of the RFID tag between the unrestricted state and the restricted state in accordance with the attached state.

In the present invention, the unlimited state is a state where the functions that can be executed are not limited.

For example, an RFID tag that has a function for reading and writing data stored in an IC chip means that both a reading function and a writing function are possible. On the other hand, the limited state is a little At least some of the functions are restricted. That is, in the RFID tag of the present invention, the restriction state is a state in which only one of the function of reading and writing the data stored in the memory of the IC chip is impossible. Most restrictive states include not only the state in which only one of the reading function and the writing function is impossible, but also the state in which both the reading function and the writing function are impossible.

[0010] In the present invention, when the RFID tag is attached to the object or when the object force is also removed, it is arbitrary whether the state is set to an unrestricted state or a restricted state. In other words, in the RFID tag of the present invention, the switching means switches to the unrestricted state when the RFID tag is attached to the object, and restricts when the RFID tag is removed from the object. It can be a means for switching to a state. On the contrary, in the RFID tag of the present invention, the switching means switches to the restricted state when the RFID tag is attached to the object, and when the RFID tag is also removed from the object force. It is good also as a means to switch to the said unlimited state.

[0011] Further, the RFID tag of the present invention is an RFI D tag having a restriction state of a plurality of patterns whose functions are restricted, and the state of the RFID tag is set according to the attachment state of the RFID tag to an object. It is characterized by having a switching means for switching in a restricted state of a plurality of patterns.

[0012] In a preferred embodiment of the present invention, various modes can be considered as the switching means, and as an example, a configuration in which switching is performed by a means for short-circuiting a conductor of an antenna connected to an IC chip and a means for conducting, As another example, it is possible to adopt a configuration in which the capacitance of the antenna connected to the IC chip is increased or decreased to switch by means of changing the resonance frequency of the antenna.

[0013] Here, the following specific examples are conceivable as the configuration for switching between the means for short-circuiting the conductor of the antenna mentioned above and the means for conducting. For example, the means for short-circuiting the conductor of the antenna is configured to connect in parallel between a pair of connection terminals provided at both ends of the antenna by contact of the movable contact, and the means for conducting the conductor of the antenna is the above-mentioned movable contact. The connection terminals can be disconnected by being separated from each other. Alternatively, the means for short-circuiting the antenna leads can be separated by moving the contact points on one side of the antenna. The pair of connection terminals provided at the end line portion may be disconnected from each other, and the means for conducting the antenna conductor may be configured to connect the connection terminals in series by contact of the movable contact.

[0014] On the other hand, the following specific example is conceivable as a configuration for switching by means of changing the resonance frequency of the antenna mentioned in the latter. For example, the electrode portion is brought into contact with the insulating layer applied on the antenna to increase the antenna capacitance, and the electrode portion is separated from the insulating layer to reduce the antenna capacitance. can do. Alternatively, the release paper having the electrode layer is attached to the adhesive layer applied on the antenna to increase the capacitance of the antenna, and the release paper having the electrode layer is peeled off. It is good also as a structure which reduces the electrostatic capacitance of an antenna.

In the present invention, the data transmission method between the RFID tag and the reader / writer may be any one of an electromagnetic coupling method, an electromagnetic induction method, and a microwave method, and therefore differs depending on the data transmission method. Regarding the shape of the antenna, a shape suitable for each transmission method, for example, an antenna of various shapes such as a looped coil antenna or a linear dipole antenna can be employed.

The invention's effect

As is apparent from the above configuration, according to the RFID tag of the present invention, the state of the RFID tag is not restricted according to the state of attachment of the RFID tag to the object, and the function is not restricted. Since the configuration having the switching means for switching between the restricted states is adopted, it is possible to prevent the human error that erroneously writes the data to the unintended RFID tag. Therefore, for example, in mail order sales return management, data related to other returned products may be written to unused tags other than RFID tags attached to returned products, or conversely, written RFID tags already attached to returned products. Data can be prevented from being overwritten, data matching between the product and the RFID tag is ensured, and a highly reliable system can be constructed.

Brief Description of Drawings

FIG. 1 is an external view showing a configuration of an RFID tag according to a first embodiment.

FIG. 2 is a cross-sectional view taken along line AA of the RFID tag in FIG. FIG. 3 (a) is a circuit block diagram showing a configuration of the RFID tag of FIG.

FIG. 3 (b) is a circuit block diagram showing the configuration of the RFID tag in FIG.

[4] FIG. 4 is an explanatory view showing a state where the RFID tag of FIG. 1 is attached to an object.

FIG. 5 is an explanatory view showing a state where the RFID tag of FIG. 1 is also removed from the object force.

FIG. 6 is a circuit block diagram showing a configuration of an RFID tag according to a second embodiment.

圆 7 (a)] is a cross-sectional view and a circuit block diagram showing the configuration of the RFID tag of the third embodiment. 圆 7 (b)] is a cross-sectional view and a circuit block diagram showing the configuration of the RFID tag of the third embodiment. [8] FIG. 8 is a cross-sectional view showing a configuration of an RFID tag according to a fourth embodiment.

FIG. 9 is a circuit block diagram showing a configuration of an RFID tag according to a fifth embodiment.

Explanation of symbols

1 RFID tag

2 antennas

21 Koinore

22 end line

23 Power feeding unit

3 IC chip

4 inlets

5 Protective layer

6 switches

61 movable contacts

62a, 62b connection terminal

63a, 63b connection terminal

7 switches

71a 1st electrode

71b Second electrode 73 release paper

74 electrode layers

75 adhesive layer

8 switches

81 ground terminal

82 lead terminals

83 light terminal

84 1st movable contact

85 Second movable contact

10 objects

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0020] (First embodiment)

Fig. 1 is an external view showing the configuration of the RFID tag of the first embodiment, Fig. 2 is a cross-sectional view of the RFID tag, Fig. 3 is a circuit block diagram of the RFID tag, and Fig. 4 is the RFID tag attached to an object. FIG. 5 is an explanatory view showing a state, and FIG. 5 is an explanatory view showing a state in which the RFID tag is removed from an object.

[0021] The RFID tag 1 of the present embodiment adopts an electromagnetic induction method as a data transmission method with a reader / writer, and when attached to the object 10, it is in an unrestricted state in which reading and writing can be performed without restricting functions. The function is limited when the object 10 is removed from the object 10, and the reading / writing is restricted.

As shown in FIG. 1 and FIG. 2, the RFID tag 1 is composed of an inlet 4 in which an antenna 2 and an IC chip 3 are mounted on an insulating base material, and the outer periphery of the inlet 4 is narrow. It is covered with a protective layer 5 made of a fat film.

[0023] The antenna 2 is a coil antenna suitable for an electromagnetic induction system, and includes a coil portion 21 wound in a loop shape, and two end line portions 22 that extend linearly across the coil portion 21 to the outside thereof. , 22 and a pair of power feeding parts 23, 23 provided at the tip of the end line part 22. This antenna 2 is formed by etching a copper foil force conductor on the base material, Are connected to the pair of power supply terminals of the IC chip 3 by soldering. When receiving an electromagnetic wave radiated from an external reader / writer, the antenna 2 generates an electromotive force due to electromagnetic induction at both ends of the coil unit 21, and the current flowing through the coil unit 21 by the electromotive force is supplied from the power feeding unit 23 to the IC. It has a function to operate chip 3.

The IC chip 3 is an electronic component that performs communication processing of various data with the reader / writer, and includes a CPU, a modulation / demodulation circuit, and a nonvolatile memory such as an EEPROM. The IC chip 3 operates without a battery due to the electromotive force generated in the antenna 2. The current supplied from the power feeding unit 23 of the antenna 2 is supplied to the CPU with DC smoothing, thereby starting the CPU. . The activated CPU detects the modulated wave received via the antenna 2 via the antenna 2 by the modulation / demodulation circuit, demodulates it into data, and performs predetermined processing according to the command of the demodulated data. In other words, when the command is a write process, the CPU stores the received data in the nonvolatile memory so that it can be rewritten, and when the command is a read process, the CPU reads the data stored in the nonvolatile memory. Then, the signal is modulated by the modulation / demodulation circuit, and the modulated wave is transmitted from the antenna 2 to the reader / writer.

[0025] The RFID tag 1 of the present embodiment is characterized in that it includes switching means for switching between an unrestricted state in which reading and writing are possible and a restricted state in which reading and writing are impossible according to the state of attachment to the object 10. Various specific configurations of the switching means are conceivable, but in this embodiment, by providing a switch portion 6 for short-circuiting or conducting the conductor from the antenna 2 to the IC chip 3, the power supply portion 23 of the antenna 2 can be connected to the IC. A configuration that controls the current supplied to chip 3 is adopted.

[0026] The specific structure of the switch unit 6 is a clip structure as shown in the figure, and the power ON / OFF function can be realized simultaneously with the attachment function to the object 10 by using the opening / closing operation of the clip. Yes. That is, the switch portion 6 also has a leaf spring-like clip force obtained by bending a metal plate in a curved shape, and is bonded and fixed to the protective layer 5 on the back surface of the base force inlet 4 of the clip and integrated with the RFID tag 1. . Therefore, the RFID tag 1 integrated with the clip can be detachably attached to the object 10 by opening the clip and sandwiching the object 10 in the gap.

[0027] A movable contact 61 is provided at the tip of the clip, and the surface of the inlet 4 facing this The protective layer 5 is not covered only in the region corresponding to the movable contact 61, and the pair of connection terminals 62a and 62b provided on the end line portions 22 and 22 on both sides of the antenna 2 are exposed to the outside. There is. In addition, the tip of the clip is always urged in the closing direction by the spring force of the curved portion, so that the movable contact 61 is piled on the spring force of the curved portion where the movable contact 61 is in contact with both connection terminals 62a and 62b simultaneously. By opening the clip, the two connection terminals 62a and 62b are separated from each other.

[0028] The electrical circuit configuration of the RFID tag 1 having such a structural force will be described. As shown in FIG. 3, the switch unit 6 is arranged between the antenna 2 and the IC chip 3, and the antenna 2 A connecting terminal 62a provided on one end line portion 22 of the antenna, a connecting terminal 62b provided on the other end line portion 22 of the antenna 2, and a movable contact for connecting the connecting terminals 62a and 62b in parallel. 61.

[0029] That is, when the clip is closed by removing the RFID tag 1 from the object, the movable contact 61 at the tip of the clip blocks the end line portion 22 of the antenna 2 as shown in FIG. Since it contacts the terminals 62a and 62b, the movable contact 61 closes and acts as a kind of jumper wire, and the connection terminals 62a and 62b are connected in parallel. Therefore, the conductor wire between the coil portion 21 and the power feeding portion 23 in the antenna 2 is short-circuited, and the current supply from the power feeding portion 23 to the IC chip 3 is interrupted. This is the power-off state, and the IC chip 3 does not operate, so communication between the reader / writer and the RFID tag 1 becomes impossible, and data cannot be read from or written to the memory.

[0030] On the other hand, when the clip is opened by attaching the RFID tag 1 with the object sandwiched between them, the movable contact 61 at the tip of the clip also has the force of both connection terminals 62a and 62b of the antenna 2 as shown in FIG. 3 (b). Since they are separated from each other, the movable contact 61 opens and the connection between the connection terminals 62a and 62b is cut off. Therefore, the conducting wire between the coil portion 21 and the power feeding portion 23 in the antenna 2 is conducted, and the current flowing through the antenna 2 is supplied from the power feeding portion 23 to the IC chip 3. This is the power ON state, and the IC chip 3 operates, so that communication between the reader / writer and the RFID tag 1 becomes possible, and data can be read from and written to the memory.

As described above, the RFID tag 1 of the present embodiment can be read and written without any function restriction when attached to the object 10, and can be read with the function restricted when detached from the object 10. Since the RFID tag 1 attached to the product is used repeatedly as in the above-mentioned return management, unused tags other than the RFID tag 1 attached to the returned product are configured. It is suitable as an application to prevent data related to other returned products from being written on the screen.

[0032] (Second Embodiment)

FIG. 6 is a circuit block diagram showing the configuration of the RFID tag of the second embodiment. Note that the same reference numerals in the present embodiment denote the same components as those in the first embodiment, and a detailed description thereof will be omitted.

[0033] The force of the RFID tag 1 of the present embodiment adopting the electromagnetic induction method Contrary to the first embodiment described above, the function of the RFID tag 1 when it is attached to the object 10 is limited so that it cannot be read and written. On the other hand, when the object 10 is removed from the object 10, the function restriction is released, and an unrestricted state in which reading and writing can be performed is configured. In the present embodiment, the configuration in which the switch portion 6 for short-circuiting or conducting the conductor of the antenna 2 is provided in common with the first embodiment, but the switch portion 6 is disposed between the antenna 2 and the IC chip 3, It differs in that it has a pair of connection terminals 63a, 63b that are spaced apart from each other on the end line portion 22 on one side of the antenna 2 and a movable contact 61 that connects the connection terminals 63a, 63b in series. Yes. Note that the coil portion 21 and the power feeding portion 23 are connected to the end line portion 22 on the other side of the antenna 2.

That is, when the clip is closed, the movable contact 61 at the tip of the clip comes into contact with both connection terminals 63a and 63b of the antenna 2, so that the movable contact 61 is closed and the connection terminals 63a and 63b are connected in series. Become. Therefore, the conductive wire between the coil part 21 and the power feeding part 23 in the antenna 2 is conducted, and the current flowing through the antenna 2 is supplied from the power feeding part 23 to the IC chip 3. This is the power-on state, and the IC chip 3 operates, so that communication between the reader / writer and the RFID tag 1 is possible, and data can be read from and written to the memory.

On the other hand, when the clip is opened, the movable contact 61 at the tip of the clip is separated from both connection terminals 63a and 63b of the antenna 2, so that the movable contact 61 is opened and the connection between the connection terminals 63a and 63b is interrupted. It becomes a state. Therefore, the conducting wire between the coil part 21 and the power feeding part 23 in the antenna 2 is short-circuited, and the current supply from the power feeding part 23 of the antenna 2 to the IC chip 3 is cut off. This is a power-off state, and IC chip 3 does not operate. Communication with tag 1 is disabled, and data cannot be read from or written to memory.

[0036] As described above, the RFID tag 1 of the present embodiment has a limited function when it is attached to the object 10, and cannot be read / written. When the RFID tag 1 is removed from the object 10, the function restriction is released and the read / write is disabled. Therefore, when the RFID tag 1 attached to the product is used repeatedly as in the return management described above, the data of the written RFID tag 1 already attached to the returned product is overwritten. It is suitable as an application for preventing the occurrence of the above. Note that the function of this embodiment is not used in combination with the function of the first embodiment, but the function of either embodiment is selected and used according to the purpose of use.

[0037] (Third embodiment)

FIG. 7 is a cross-sectional view and a circuit block diagram showing the configuration of the RFID tag according to the third embodiment. Note that the same reference numerals in the present embodiment denote the same components as those in the above-described embodiment, and a detailed description thereof will be omitted.

[0038] The RFID tag 1 of the present embodiment increases or decreases the capacitance (capacitance) of the antenna 2 that is not connected to the switch unit 6 that short-circuits or conducts the conductor of the antenna 2 as in the first and second embodiments described above. A feature is that a switch portion 7 for changing the resonance frequency is provided.

As shown in FIG. 7, this RFID tag 1 has a conductive first electrode portion 71a at the tip of a switch portion 7 having a metal clipping force in an inlet 4 on which an antenna 2 and an IC chip 3 are mounted. The second electrode portion 71b is provided at the rear end, and the insulating layer 72, which is a dielectric material having a resin film force, is provided over the entire outer periphery of the inlet 4. As shown in FIG. 5B, the first electrode portion 71a is arranged so as to cut vertically between the antenna 2 and the IC chip 3, and the antenna 2 on the inlet 4 is not exposed to the outside. On the other hand, the second electrode portion 71b is embedded from the side surface of the tag and is always connected to the end line portion 22a on one side of the antenna 2. The natural resonance frequency of antenna 2 is set to an optimum value so that communication can be performed with the reader / writer when the clip is opened and the first electrode portion 71a and the insulating layer 72 are not in contact with each other. Has been.

[0040] According to the RFID tag 1 having such a structure, when the clip is closed, the first electrode portion 71a and the insulating layer 72 are in contact with each other, and the insulating layer sandwiched between the first electrode portion 71a and the second electrode portion 71b. 72 between the electrodes Functions as a dielectric. As a result, a closed circuit is formed by the antenna 2 and the switch portion 7, and a parasitic capacitance capacitor is formed on each of the end line portion 22a on the one side and the end line portion 22b on the other side of the antenna 2. The That is, the antenna 2 becomes an LC resonance circuit composed of the coil section 21 and the capacitor, and is stored in the capacitor to increase the capacitance. As a result, the resonance frequency of the antenna 2 is shifted, and the reader / writer and the RFID tag 1 Communication is obscured.

[0041] Therefore, when the clip is closed, that is, when the RFID tag 1 is removed from the object 10, the function may be limited so that data cannot be read from or written to the memory of the IC chip 3 as in the first embodiment. it can. Contrary to this structure, if the clip is closed and set so that the optimum resonance frequency is obtained when the capacitor is formed, when the clip is opened, that is, RFID tag 1 is the target 10 It is possible to limit the function so that the resonance frequency shifts when it is attached to the IC chip and communication becomes impossible, and data cannot be read from or written to the memory of the IC chip 3.

[0042] (Fourth embodiment)

FIG. 8 is a cross-sectional view showing the configuration of the RFID tag of the fourth embodiment. In the present embodiment, the same reference numerals are given to components common to the above-described embodiments, and detailed description thereof is omitted.

[0043] The RFID tag 1 of the present embodiment is the same as the third embodiment in that it employs a configuration in which a switch unit 7 that changes the resonance frequency by increasing or decreasing the capacitance of the antenna 2 is employed.

RU

[0044] As shown in Fig. 8, the RFID tag 1 has a plurality of inlets 4 each mounted with an antenna 2 and an IC chip 3 attached on a sheet-like release paper 73, which is rolled into a roll shape. This is the rotated inlet roll paper. In this inlet roll paper, the inlet 4 and the release paper 73 are detachably attached via an adhesive layer 75 applied to the back surface of the inlet 4 as shown in FIG. The switch portion 7 is configured by providing an electrode layer 74 coated with a conductive paint limited to a region corresponding to the antenna 2. In addition, when the inlet 4 is peeled off from the release paper 73 and the adhesive layer 75 and the electrode layer 74 are not in contact with each other, the inherent resonance frequency of the antenna 2 is set so that communication can be performed with the reader / writer. Set to optimal value It is.

[0045] According to the RFID tag 1 made of such an inlet roll paper, a clip for attaching to the object 10 is unnecessary, and the inlet 4 peeled off from the release paper 73 is directly attached to the object 10 by the adhesive layer 75. Can be attached. In addition, when the inlet 4 is adhered to the release paper 73 and is V, the adhesive layer 75 sandwiched between the electrode layer 74 and the antenna 2 functions as a dielectric between the electrodes, thereby forming a parasitic capacitance capacitor. Is done. That is, as in the third embodiment, the antenna 2 becomes an LC resonance circuit including the coil unit 21 and the capacitor, and is stored in the capacitor to increase the capacitance. As a result, the resonance frequency of the antenna 2 is shifted and the reader / writer is not connected. Communication becomes impossible.

[0046] Therefore, the function can be restricted so that data cannot be read from and written to the memory of the IC chip 3 when the inlet 4 is attached to the release paper 73, and the restriction is restricted when the inlet 4 is peeled off from the release paper 73. The data can be read from and written to the memory only after it is released and pasted on the object 10. Contrary to this structure, if the inlet 4 is set on the release paper 73 so that the optimum resonance frequency is obtained, the inlet 4 is peeled off and attached to the object 10. It is also possible to restrict the function so that the resonance frequency is shifted and communication becomes impossible and data cannot be read from and written to the IC chip 3.

[0047] (Fifth embodiment)

FIG. 9 is a circuit block diagram showing the configuration of the RFID tag of the fifth embodiment. In the present embodiment, the same reference numerals are given to the same components as those in the above-described embodiment, and the detailed description thereof is omitted.

[0048] As shown in FIG. 9, the RFID tag 1 of the present embodiment disables all the communication functions in the inlet 4 on which the antenna 2 and the IC chip 3 are mounted, depending on the attachment state to the object 10. Therefore, a switch unit 8 for switching the operation mode of the IC chip 3 is provided so that only one of the reading function and the writing function is disabled. The switch unit 8 includes a ground terminal 81 connected to the power supply terminal of the IC chip 3, a read lead terminal 82 and a write write terminal 83 connected in parallel to the ground terminal 81. In addition, the lead terminal 82 is provided with a first movable contact 84 that switches between conduction and non-conduction with the ground terminal 81, and the write terminal 83 similarly conducts with the ground terminal 81. And a second movable contact 85 for switching non-conduction.

[0049] In such a structure, for example, when the RFID tag 1 is attached to an object, if the first movable contact 84 is closed and the second movable contact 85 is opened, the ground terminal 81 and lead terminal 82 are electrically connected. Thereby, only the reference potential card terminal 82 applied from the power feeding unit 23 of the antenna 2 to the ground terminal 81 is supplied, and only the function of reading data stored in the memory of the IC chip 3 is enabled. On the other hand, when the RFID tag 1 is also removed, the first movable contact 84 is opened and the second movable contact 85 is closed, whereby the ground terminal 81 and the light terminal 83 are brought into conduction. Therefore, since the reference potential force S applied to the ground terminal 81 from the power feeding section 23 of the antenna 2 is supplied only to the S write terminal 83, only the function of writing data stored in the memory of the IC chip 3 is effective. Can be made. The switching between the reading function and the writing function may be the reverse of the above example.

[0050] As described above, according to the RFID tag 1 of the present embodiment, only one of the reading function and the writing function can be invalidated as a function-restricted turn corresponding to the attachment state to the object 10. As a result, the convenience of the RFID tag 1 is significantly improved. Note that the above example is an example of switching among a plurality of patterns in a restricted state depending on the state of attachment to the object 10, but not limited to this, an unrestricted state depending on the state of attachment to the object 10 It is also possible to switch between and one of the restricted states of multiple patterns.

Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

This application is based on a Japanese patent application filed on October 18, 2005 (Japanese Patent Application No. 2005-303324), the contents of which are incorporated herein by reference.

Claims

The scope of the claims

[1] An RFID tag that has an unrestricted state and a restricted state with a function restriction, and the state of the RFID tag depends on the attachment state of the RFID tag to the object. An RFID tag comprising switching means for switching between the above and the restricted state.

[2] The RFID tag according to claim 1, wherein the restricted state is a state in which only one of a reading function and a writing function of data stored in the memory of the IC chip is impossible.

[3] The switching means is means for switching to the unrestricted state when the RFID tag is attached to an object, and switching to the restricted state when the RFID tag is also removed from the object force. The RFID tag according to claim 1 or 2.

[4] The switching means is means for switching to the restricted state when the RFID tag is attached to an object, and switching to the unrestricted state when the RFID tag is also removed from the object force. The RFID tag according to claim 1 or 2, wherein the RFID tag is characterized.

[5] An RFID tag having a restriction state of a plurality of patterns whose functions are restricted, and switching the state of the RFID tag among the restriction states of the plurality of patterns according to the attachment state of the RFID tag to an object. An RFID tag comprising means.

6. The RFID tag according to any one of claims 1 to 5, wherein the switching means is switched by means for short-circuiting the conductor of the antenna connected to the IC chip and means for conducting.

7. The switching force according to any one of claims 1 to 5, wherein the switching means is switched by means for changing the resonance frequency of the antenna by increasing or decreasing the capacitance of the antenna connected to the IC chip. RFID tag according to item.

[8] The means for short-circuiting the conductor of the antenna is a means for connecting the pair of connection terminals provided on the end line portions on both sides of the antenna in parallel by contact of the movable contact, and means for conducting the conductor of the antenna. 7. The RFID tag according to claim 6, wherein the connection terminals are disconnected by the separation of the movable contact.

[9] The means for short-circuiting the conductor of the antenna is based on the separation of the movable contact on one side of the antenna. A pair of connection terminals provided in the end line portion is disconnected, and the means for conducting the antenna conductor is to connect the connection terminals in series by contact of the movable contact. The RFID tag according to claim 6, wherein:

[10] The means for changing the resonance frequency of the antenna increases the capacitance of the antenna by contacting the electrode portion with an insulating layer applied on the antenna, and the electrode portion is an insulating layer cover. 8. The RFID tag according to claim 7, wherein the RFID tag reduces the capacitance of the antenna by being separated from the antenna.

[11] The means for changing the resonance frequency of the antenna increases the electrostatic capacity of the antenna by attaching a release paper having an electrode layer to an adhesive layer applied on the antenna. 8. The RFID tag according to claim 7, wherein the capacitance of the antenna is reduced by peeling a release paper having a layer.