JP5137123B2 - Wireless tag and method of using the same - Google Patents

Description

  The present invention relates to a wireless tag that performs information communication by a radio wave system and a method of using the wireless tag.

  A wireless tag including an IC chip that stores information and an antenna unit transmits and receives data to and from a reader / writer through wireless communication using electromagnetic waves. The wireless tag technology is used in many fields such as logistics, merchandise management, and security. As an example, a non-contact IC card and its structure are disclosed in Patent Document 1.

  In an ordinary wireless tag, an electromagnetic induction method and a radio wave method are used as a transmission method, a passive type and an active type are used as a communication method, and a frequency of an electromagnetic wave to be used is 135 kHz or less, a 13.56 MHz band, a UHF band (860 to 960 MHz). ), Microwave band (2.45 GHz) and the like are put into practical use. In a wireless tag of 135 kHz or less and 13.56 MHz band, transmission is performed by an electromagnetic induction method using a coil antenna, and transmission by a radio wave method is performed using a dipole antenna in the UHF band and the microwave band.

  The passive type wireless tag rectifies radio waves of a predetermined frequency transmitted from a reader / writer into direct current inside the IC chip to obtain driving power. In addition, in an active type having a power source such as a button type battery, a film-like battery, or a large-capacity capacitor inside a wireless tag, information can be transmitted spontaneously without being transmitted by a radio wave from a reader / writer.

  Radio type wireless tags have a longer communication distance with readers / writers than electromagnetic induction types, and in particular passive type wireless tags are less expensive because they do not have an internal power supply compared to active types. Therefore, applications for replacing conventional bar codes are being studied.

  A general IC chip used for a wireless tag is obtained by forming a circuit on a silicon wafer having a diameter of 6 to 12 inches and dicing it into individual pieces. On the other hand, the antenna part is formed by etching an aluminum or copper foil attached on a thin polyester film substrate as in Patent Document 1 into a desired pattern, or as disclosed in Patent Document 2. It is formed by printing a pattern with a conductive paint on a substrate.

  In general, the radio wave used for communication between a wireless tag and a reader / writer has a longer communicable distance as transmission power increases. In addition, the lower the frequency used, the smaller the propagation loss in the air, and the longer the communication distance.

  However, there are regulations set by each country regarding the frequency and transmission power of radio waves that can actually be used. Therefore, when designing a communication system between a wireless tag and a reader / writer, The frequency and transmission power are selected so as to obtain the maximum effect for the intended purpose.

  Further, even within the same country, a plurality of frequency bands are determined depending on the application. For example, in a radio tag of a normal radio system in Japan, the 953 MHz band and the 2.45 GHz band are used. The antenna used is, for example, a dipole antenna as disclosed in Patent Document 3 as a non-contact type semiconductor tag, an antenna that is T-matched to the dipole antenna, or the like.

  The wireless tag is attached to the target article by attaching it to the object or suspending it with a string, and is used for inventory management of goods, receipt / shipment history management, and the like. IC chips store identification numbers, receipt / shipment history information, etc. as data, and are recently used for authenticity judgment of high-quality products using the fact that it is difficult to tamper with data, and for recycling management using history information. Sometimes. As an application example of a wireless tag, as disclosed in Patent Document 4, there is an ID label that detects that it has been peeled off from an identification object, and is used for security applications that detect whether or not a package or container has been opened. Sometimes.

  In an electromagnetic induction type wireless tag with a use frequency of 13.56 MHz, an antenna is placed in the opening part of the container, and when the container is opened, the antenna is cut and power is not supplied to the IC chip, so communication is impossible. It is possible to detect whether or not the container is opened by using the above. However, the electromagnetic induction method is easily affected by surrounding metals, and the communicable distance is not as long as the radio wave method. In addition, since the antenna becomes large, applicable containers are limited.

Japanese Patent Laid-Open No. 10-200288 Japanese translation of PCT publication No. 2002-517870 JP 2000-222540 A JP 2001-13874 A

  When opening a container using a 953 MHz band or 2.45 GHz band wireless tag with a long communication distance, even if a part of the antenna is cut by opening the container, the distance from the cutting site or the reader / writer Depending on the conditions such as, communication may be possible, and there is a problem that opening may not be detected reliably.

  In addition, radio wave type radio tags usually use dipole antennas, which have a smaller area than coil antennas used in the electromagnetic induction method, and in order to detect opening reliably, the opening part of the container and the radio tag It is necessary to accurately match the position and direction of the attachment, and the workability when attaching the wireless tag to the container is poor, and the shape of the applicable container and the print design are restricted.

  The present invention has been made in order to solve the above-described problems of the prior art, and has an object of having a long communication distance with a reader / writer, good workability when a wireless tag is attached to a container, and applicable. An object of the present invention is to provide a wireless tag capable of reliably detecting opening and a method for using the same, with few restrictions on the shape of the container and the print design.

According to the present invention, a pair of radiating electrodes and an antenna part that constitutes a dipole antenna by a feeding line having one end connected to the radiating electrode, and an IC chip connected to the other end of the feeding line are formed on a substrate. a wireless tag, a part or all of the feed line, said die comprising a shaped part is not parallel to the antenna axis of the pole antenna, distribution of the pair of discharge elevation electrode is perpendicular to the antenna axis equally a geometric center axis, the intersection between the antenna axis as the center of symmetry, Ri do a shape point-symmetrical of the feed line, and the non-parallel shape portion, a straight line near so that including the intersection A wireless tag characterized by being configured is obtained.

  According to the present invention, the wireless tag is attached to the container via an adhesive so that the opening portion of the container crosses the feeder line, and whether or not communication with the wireless tag is possible, A method of using a wireless tag, characterized by detecting whether the container has been opened or not, can be obtained.

  In the radio wave type radio tag, even when the antenna, that is, the radiation electrode is cut as in the electromagnetic induction type, the gain is reduced, but communication may be possible depending on the distance from the reader / writer. This is because even if the radiation electrode is cut at the time of opening, a part of the pair of feed lines and the radiation electrode may remain and the function as an antenna may not be completely lost. This can occur whether the antenna axis of the wireless tag is attached in a parallel direction or in an orthogonal direction.

  In the present invention, the opening detection is performed by cutting the feed line instead of the radiation electrode of the wireless tag. In a conventional wireless tag with a feed line parallel to the antenna axis, if the unsealed part and the antenna axis are attached in parallel, the feed line may not be cut by unsealing. You must attach it or intentionally attach the RFID tag diagonally. Therefore, in a wireless tag that is formed on a base material or a mount and often has a rectangular outer shape, the applicable container and printing design are restricted.

  By configuring a part or all of the feed line to have a shape that is not parallel to the antenna axis of the dipole antenna, the unsealed part crosses the feed line even if the unsealed part and the antenna axis are arranged in parallel. Therefore, the function as a dipole antenna is lost by cutting at least one of the pair of feed lines, and communication with the reader / writer cannot be performed. Therefore, if it is confirmed whether or not the communication of the wireless tag is possible, it is possible to reliably detect whether or not the container is opened due to the cutting of the feed line.

  In the configuration of the present invention, it can be applied so that the opening part of the RFID tag traverses the feeder line even if the antenna axis of the wireless tag is attached in parallel or orthogonal to the opening part of the container. Fewer constraints on possible containers and print designs. In addition, the wireless tag is attached to the surface in contact with the container through an adhesive material, so that the attachment to the container is facilitated and the workability is improved, and the unsealed portion and the power supply line are in close contact with each other, so that the power supply line is cut off. It is done more reliably.

  In the present invention, the configuration is such that the shape of the feed line is point-symmetrical with the geometrical central axis that is perpendicular to the antenna axis and the pair of radiation electrodes being equally divided and the intersection of the antenna axis and the center of symmetry. Thus, when the opening part of the container and the antenna axis of the wireless tag are arranged in parallel, the tolerance of deviation with respect to the mounting position accuracy of the wireless tag necessary for the opening part to cross the feeder line can be increased. Therefore, attachment of the wireless tag is facilitated and workability is improved, and the feed line is more reliably cut.

  According to the present invention, the distance that can be communicated with the reader / writer is long, the workability when attaching the wireless tag to the container is good, there are few restrictions on the shape of the applicable container and the print design, and the opening is ensured. It has become possible to provide a wireless tag that can be detected and a method of using the wireless tag.

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

  1A and 1B are diagrams showing a configuration of a wireless tag according to an embodiment of the present invention. FIG. 1A shows a schematic front view, and FIG. 1B shows a schematic side view.

  In FIG. 1, the wireless tag 100 forms a radiation electrode 103 and a feed line 102 on a base material 104 by a foil of a conductive material, and the feed line 102 is connected to the IC chip 101. An adhesive material 105 is preferably provided on the surface of the base material 104 that contacts the container.

  The material of the base material 104 can be appropriately determined by the container opening means. In other words, if you do not use utensils or knives when opening the container, use paper or a resin film that breaks easily, and if you intend to prevent the container from being opened unintentionally, mechanical strength High PET (polyethylene terephthalate), polyimide film, glass epoxy substrate, etc. are preferably used.

  The radiation electrode 103 and the feed line 102 are preferably formed in a desired pattern by etching a metal foil such as aluminum or copper or printing a conductive paint mainly composed of silver particles.

  Although the radiation electrode 103 constitutes a dipole antenna, it can be used not only in a rectangular shape as shown in FIG. 1 but also in various modifications depending on the use of the wireless tag and various conditions. That is, a shape that is partially bent or a so-called meander pattern having a polygonal line shape may be appropriately selected according to the application and characteristics.

  2A and 2B are front views for explaining the configuration of the wireless tag according to the embodiment. FIG. 2A is a conventional embodiment, FIG. 2B is an embodiment according to the present invention, and FIG. Represents another embodiment according to the present invention.

  In FIG. 2, in the conventional embodiment of FIG. 2A, the antenna shaft 106 of the radiation electrode 103 formed on the substrate 104 and the feed line 102 connected to the IC chip 101 are arranged coaxially. This is an example. Depending on the configuration, the feed line 102 is arranged in parallel with the antenna shaft 106, but may be offset and not coaxial.

  In FIG. 2A, when the antenna shaft 106 of the wireless tag 100 and the opening portion of the container are attached in parallel, in order to cut the feed line 102, the displacement of the attachment position of the wireless tag 100 is set to the feed line width B. Must be in range. The feed line width B with respect to the radiation electrode width A in a general wireless tag is a fraction to a few tenths, and the positioning at the time of attaching the wireless tag 100 is not easy, and the IC chip 101 and the feed line There may be a situation where communication is possible without disconnecting the connection 102.

  On the other hand, in the wireless tag according to the present invention shown in FIG. 2B, the central axis 107 of the feeder line is arranged so as to form an inclination angle θ with respect to the antenna axis. When the antenna shaft 106 and the opening of the container are attached in parallel, the attachment position shift C allowed for the wireless tag 100 to cut the feed line 102 is expressed by the following formula (1). ).

  C = A-2 (B / cos θ) (1)

  As an example, in a wireless tag having a radiation electrode width A of 10 mm, a feed line width B of 1 mm, and an inclination angle θ of 45 °, an allowable mounting position deviation C is expressed by Expression (2).

  C = 10−2 × (1 / cos45 °) ≈7.2 (mm) (2)

  In the configuration of FIG. 2A, the allowable attachment position deviation C is the same as the feed line width B at the maximum, but the opening is surely detected even if the feed line 102 is cut in the narrow range. 2 (b), the allowable mounting position deviation C is greatly enlarged.

  In addition, in the wireless tag according to the present invention shown in FIG. 2C, the feeding point portion connected to the radiation electrode 103 of the feeding line 102 is a shape portion parallel to the antenna shaft 106, and the other feeding lines 102 are shown in FIG. In the same manner as in (), the shape portion is not parallel to the antenna axis 106. In this case, the attachment position shift C allowed for the wireless tag 100 to cut the feed line 102 is expressed by Expression (3) when the radiation electrode width A and the feed line width B are used.

  C = A-2B (3)

  As an example in this case, an attachment position shift C allowed in a wireless tag having a radiation electrode width A of 10 mm and a feed line width B of 1 mm is expressed by Expression (4).

  C = 10−2 × 1 = 8 (mm) (4)

  In the configuration shown in FIG. 2C, the allowable mounting position deviation C is further expanded as compared with the configuration shown in FIG. 2B, and the distance between the pair of radiation electrodes 103 is not dependent on the inclination angle θ. It is also possible to cope with the inclination angle θ set to 90 ° when it is narrow and restricted by the portion where the feeder line 102 is disposed.

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

Example 1
FIG. 3 is a perspective view showing the arrangement of the wireless tag according to the first embodiment of the present invention.

  This embodiment is configured to detect the presence or absence of opening in order to prevent modification of an electric circuit board housed in a case 201 and a cover 202 made of a plastic material.

  The wireless tag 100 includes an IC chip 101, a feed line 102 that is not parallel to the antenna axis, and a rectangular radiation electrode 103. The feed line 102 and the radiation electrode 103 were formed by etching a thin aluminum layer formed on a PET substrate. The communication frequency is in the 953 MHz band, and the external dimensions of the wireless tag 100 are 10 mm long and 150 mm wide. The radiation electrode 103 functions as a dipole antenna, and the antenna axis is a geometric center line in the longitudinal direction of the radiation electrode 103. The line width of the feeder line 102 is 1 mm, and the inclination angle θ is 45 °. The IC chip 101 and the feed line 102 are connected by flip chip mounting, and an adhesive material is applied to the surface of the substrate that contacts the container.

  As shown in FIG. 3, the wireless tag 100 has an antenna portion that forms a dipole antenna by the radiation electrode 103 and the feed line 102, and the feed line 102 has a shape portion that is not parallel to the antenna axis of the dipole antenna. Therefore, the unsealed portions of the case 201 and the cover 202 were arranged so that the feeder line 102 crossed and pasted so as to seal. In order to open the case 201 and the cover 202, it is necessary to cut the wireless tag 100. By cutting the wireless tag 100, at least one of the pair of feed lines 102 is cut, and the radiation electrode 103 loses its function as a dipole antenna. Therefore, the presence / absence of opening due to cutting could be detected by confirming whether communication with the reader / writer was possible.

  The communicable distance of the wireless tag 100 according to the present embodiment is about 1 m before the case 201 and the cover 202 are opened, but the wireless tag 100 and a reader / writer (not shown) may be brought into close contact after opening. Could not communicate.

  FIG. 4 is a perspective view showing another arrangement of the wireless tag according to the first embodiment of the present invention, and shows a configuration in which the wireless tag shown in FIG. . The configuration of FIG. 3 is that the shape of the feed line 102 is such that the intersection of the geometrical central axis, which is perpendicular to the antenna axis of the dipole antenna, and the pair of radiation electrodes 103 and the antenna axis is symmetrical. If the feed line 102 of the wireless tag 100 is arranged in the opening portion of the container as shown in FIG. 4, the wireless tag 100 is placed sideways with respect to the opening portion as shown in FIG. Even if it is affixed or even if it is affixed vertically to the opening as shown in FIG. 4, the same effect can be obtained, so that it can be selected appropriately depending on the structure of the container to be affixed, the print design, and the like.

(Comparative example)
FIG. 5 is a perspective view showing the arrangement of a conventional wireless tag. The wireless tag 100 in FIG. 5 has a structure having a feed line 102 parallel to the antenna axis shown in FIG. 2A, and the wireless tag 100 is attached to the opening portion of the case 201 and the cover 202 as shown in FIG. In this case, it is difficult to arrange the feed line 102 within the width of the feed line 102, and even if the feed line 102 is opened, the feed line 102 is not cut, and communication with the reader / writer is possible.

(Example 2)
FIG. 6 is a front view showing the configuration of the wireless tag according to the second embodiment of the present invention.

  In FIG. 6, the wireless tag 300 includes an IC chip 301, a feed line 302 that is not parallel to the antenna axis, and a radiation electrode 303 having a meander pattern on a paper base material 304. The feed line 302 and the radiation electrode 303 were printed with a conductive paint mainly composed of silver particles and further plated with gold. The feeder line 302 and the IC chip 301 were connected by wire bonding.

  The communication frequency is a 2.45 GHz band, and the outer dimensions of the base material 304 are 10 mm long and 45 mm wide. The radiation electrode 303 forms a meander pattern, but functions as a dipole antenna. The width of the feeder line 302 is 2 mm, and the inclination angle is 40 °.

  A matching line 306 is connected to the radiation electrode 303 for matching with the IC chip 301. The base material 304 was affixed on the label | marker 307 by which the adhesive material was apply | coated to the surface which touches a container. The size of the label 307 is 60 mm long and 60 mm wide, and sticking position marks 308 and 309 are printed as a guide for aligning the position of the opening of the container so as to cross the feeder line 302.

  The label 307 used was a film (not shown) in which when the label 307 was peeled off after being attached, the characters were lifted and the peeled off was recognized at a glance. Also, a combination with other security means such as attaching a hologram sticker is possible.

  FIG. 7 is a perspective view showing an arrangement of wireless tags according to the second embodiment of the present invention.

  In FIG. 7, the wireless tag 300 is attached so as to seal the metal cabinet 400. The wireless tag 300 is designed for a metal material, and the communicable distance is about 20 cm. The pasting position marks 308 and 309 printed on the surface of the label can be obtained by aligning the pasting position marks 308 or the pasting position marks 309 with each other when the wireless tag 300 is pasted on the cabinet 400. The tag 300 can be easily attached to a position crossing the feed line.

  The wireless tag obtained in this embodiment can increase the distance that can be communicated with the reader / writer by using a radio wave type wireless tag, and the positional deviation allowed when the wireless tag is attached to the container is also possible. It is greatly enlarged compared with the comparative example. In addition, opening detection is possible regardless of the direction of application to the container as compared with the wireless tag of the comparative example, and there are fewer restrictions on the shape and printing design of the container that can be applied. Therefore, the distance that can be communicated with the reader / writer is long, the workability when attaching the wireless tag to the container is good, there are few restrictions on the shape of the applicable container and the print design, and the opening can be detected reliably. Possible wireless tags and how to use them can be provided.

  The present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and the present invention is not limited to the scope of the present invention. included. That is, various modifications and corrections that can naturally be made by those skilled in the art are also included in the present invention.

The figure which shows the structure of the wireless tag by embodiment of this invention, Fig.1 (a) is a schematic front view, FIG.1 (b) is a schematic side view. FIG. 2A is a diagram illustrating a conventional embodiment, FIG. 2B is a diagram illustrating an embodiment according to the present invention, and FIG. 2C is a diagram illustrating a configuration according to an embodiment of the wireless tag. The figure which shows another embodiment by this invention. The perspective view which shows arrangement | positioning of the wireless tag by Example 1 of this invention. The perspective view which shows other arrangement | positioning of the wireless tag by Example 1 of this invention. The perspective view which shows arrangement | positioning of the conventional wireless tag. The front view which shows the structure of the wireless tag by Example 2 of this invention. The perspective view which shows arrangement | positioning of the wireless tag by Example 2 of this invention.

Explanation of symbols

100, 300 Radio tag 101, 301 IC chip 102, 302 Feed line 103, 303 Radiation electrode 104, 304 Base material 105, 305 Adhesive material 106 Antenna shaft 107 Center axis of feed line 201 Case 202 Cover 306 Matching line 307 Label 308, 309 Affixing position mark 400 Cabinet A Radiation electrode width B Feed line width C Mounting position deviation θ Inclination angle

Claims (2)

A radio tag formed on a substrate with a pair of radiating electrodes and an antenna part constituting a dipole antenna by a feeding line having one end connected to the radiating electrode, and an IC chip connected to the other end of the feeding line, some or all of the feed line, said die comprising a shaped part is not parallel to the antenna axis of the pole antenna, the geometrical center axis disposing a pair of discharge morphism electrodes equally perpendicular to the antenna axis wherein when, around the intersection of the symmetry of the antenna axis, the shape of the feed line is Ri do point symmetry, and the non-parallel shape portion, which is a straight line near so that configuration including the intersection A wireless tag. The wireless tag according to claim 1 is attached to the container via an adhesive so that an opening portion of the container crosses the power supply line, and confirms whether communication with the wireless tag is possible. A method of using a wireless tag, characterized by detecting the presence or absence of opening.

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