JP2004295466A - Wireless authentication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve omnidirectionality (omnidirectivity) with a single dipole antenna. <P>SOLUTION: A wireless authentication device has the flat dipole antenna and a semiconductor chip connected to the dipole antenna, and receives power and a signal from a radio wave received by the dipole antenna and emits an output from the dipole antenna. The dipole antenna is folded back to such angles as the semiconductor chip is displaced from the directions of extension of the dipole antenna. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless authentication device represented by an RFID tag or the like.
[0002]
[Prior art]
Since antennas of many conventional wireless authentication devices are designed in a shape that prioritizes communication efficiency, the size and shape of an object to which the wireless authentication device is attached are limited. As a method for dealing with such a limitation, there is a method for dealing with this by bending the dipole antenna in the extending direction of the antenna. (Patent Document 1, FIG. 1).
[0003]
Further, a linear dipole antenna has a strong directivity for wireless communication, and has almost no sensitivity in the extending direction of the rod-shaped antenna. As a technique for improving the sensitivity, there is a technique in which two dipole antennas are fixed at an angle of 90 degrees (Patent Document 1, FIG. 1).
[0004]
[Patent Document 1]
JP-A-2002-76768 [0005]
[Problems to be solved by the invention]
Patent Literature 1 only describes fixing two dipole antennas at an angle of 90 degrees.
[0006]
In other words, there is no description about a method of realizing only one dipole antenna (particularly, a flat dipole antenna).
[0007]
An object of the present invention is to eliminate the directivity of an antenna using only one dipole antenna and to achieve high sensitivity in all directions.
[0008]
[Means for Solving the Problems]
As a typical invention of the present application, a wireless authentication device that has a flat dipole antenna and a semiconductor chip connected to the dipole antenna, receives power and a signal from a radio wave received by the dipole antenna, and outputs the power and signal from the dipole antenna In some of the dipole antennas, the semiconductor chip is folded at an angle shifted from a direction in which the dipole antenna extends.
[0009]
As described above, the antenna having the same external shape can be realized by one dipole antenna regardless of whether the antenna is mounted on a rod-shaped product, a small-area plate-shaped product, or a cap-shaped product. Since a wireless authentication device having members can be used, the types of wireless authentication devices can be reduced, and production costs can be kept low.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a perspective view showing a shape of a transmission unit 1 as a wireless authentication device of the present invention before bending. The resin 13 covers the semiconductor chip 10 and the connection wires 12 and is integrated with the antenna 11. The antenna 11 is a thin plate made of a tin-plated nickel-iron alloy (Ni 42%, Fe remaining portion is exemplified), and is formed substantially linearly.
[0011]
FIG. 2 is a schematic perspective view illustrating a manufacturing process of the transmission unit 1 of the present invention. The transmission unit 1 is manufactured by mounting and joining the semiconductor chip 10 to a hoop material 20, connected by a wire 12 using a fine gold wire, protected by a resin 13, and sequentially separating the antenna 11. Originally, the hoop material 20 cut into a fixed-size strip shape is used to process each step, so that the assembling state in each step is not continuous, but is continuously displayed for convenience of illustration. In addition, it is also possible to use the hoop material 20 continuously according to the production amount, and to manufacture it as an integrated line.
[0012]
In the initial stage of the process, the hoop material 20 is provided with sprocket holes 21d and 21e in the band-shaped metal plate to form the antenna portions 21a and 21b as shown in the lower right position of the semiconductor chip in FIG. Is supplied in a state where a slit 21c is provided. Here, the slit 21c between the antenna portions 21a and 21b does not completely separate the antenna portion 21a and the antenna portion 21b, and the antenna portions 21a and 21b are connected to the hoop material 20 at both ends and can be handled as one body. The joint between the antenna portions 21a and 21b and the hoop member 20 is made narrower and further provided with a separation hole 21f to facilitate subsequent cutting.
[0013]
Next, the hoop material 20 is sent to a chip mounting process, and the semiconductor chip 10 which is provided with individual identification data in advance and is manufactured so as not to be rewritten is mounted. The semiconductor chip 10 is installed on the antenna 21b side close to the slit 21c of the hoop material 20, and is fixed by being heated. The back surface of the semiconductor chip 10 is previously plated with gold (not shown). The gold material of this plating reacts with the tin material of the plating on the surface of the hoop material 20 by heating when mounting the chip, forms a gold-tin alloy and firmly fixes the semiconductor chip 10 to the hoop material 20, And the hoop member 20 are also electrically connected.
[0014]
Further, the hoop material 20 is sent to a connection step. In the connection step, a terminal pad (not shown) on the surface of the semiconductor chip and the end of the antenna 21a are connected by the gold wire 12 by wire bonding.
[0015]
Thereafter, the hoop material 20 is sent to a molding process. In the molding step, a liquid potting resin is applied so as to cover the circuit portion of the hoop material 20, and preheating is performed to partially cure the resin to form a mold 13.
[0016]
Further, the hoop material 20 is fully heated in the heating step, and the resin is completely cured.
[0017]
Finally, in the press cutting step, the individual transmission units 1 are cut off from the hoop material 20, and the transmission unit 1 before bending shown in FIG. 1 is obtained.
[0018]
The technology used in these processes uses technology that has a proven track record for semiconductor packages with a small number of pins, such as transistors and diodes. Can be produced.
[0019]
The transmitting unit 1 can transmit the encrypted identification code to the reader 30 by applying the synchronization signal as an electromagnetic wave by the reader 30 even before the folding, but the transmission unit 1 is a product having an authentication function. The antenna 11 can be easily mounted by bending the antenna 11 according to the use form and shape, and the directivity of the antenna 11 can be reduced to facilitate authentication.
[0020]
FIG. 3 shows a shape of the transmission unit 1 in which the antenna 11 is bent in a plane. The antenna 11 is folded back at a 45 ° line with respect to the axial direction, and the antenna 11 is folded into a “C” shape. Thereby, the total length of the transmission unit 1 is reduced to about 1/3. When the antenna 11 is cut to a length of イ ン ピ ー ダ ン ス, the impedance matching between the semiconductor chip 10 and the antenna 11 is greatly broken, but since the antenna 11 is merely bent, the impedance mismatch is reduced. In addition, by bending the antenna 11, the directivity of the transmission unit 1 is reduced. The antenna 11 may be bent so that the transmission is not stable if the antennas 11 intermittently come into contact with each other. Therefore, the bent portion may be kept to such an extent that the antenna 11 does not come into contact with the antenna 11, or the antenna 11 may be bent securely to make the overlapping portion of the antenna 11 conductive. If the tip and the other end of the antenna 11 come into contact with each other, the transmission efficiency is extremely reduced.
[0021]
FIG. 4 shows the result of measuring the directionality of the detection distance when the transmitting unit 1 without bending the antenna 11 is combined with the receiver 30 without bending, and FIG. 5 shows the same transmitting unit 1 as shown in FIG. The result of having measured the directionality of the detection distance when the antenna 11 was bent is shown. 4 and 5, the maximum reach distance is set to 100%, and the reach distance in the direction of the antenna 11 is indicated relative to the curve 40. In the figure, a schematic diagram showing the direction of the transmission unit 1 is written at the center of the graph. Actually, since the transmitting unit 1 is considerably smaller than the reach distance, the schematic diagram is enlarged.
[0022]
When the antenna 11 is not bent, as shown in FIG. 4, the antenna 11 has almost no reach in the axial direction, and the sensitivity does not increase even when the end of the antenna 11 almost contacts the receiving antenna of the receiver 30. Could not be obtained. This is similar to the gain in the case of a general dipole antenna. In the case of the combination with the receiver used this time, the maximum reach of about 30 cm was shown, and a sufficient reach was obtained for small product authentication applications, but depending on the direction, sensitivity could not be obtained even if it was almost closely contacted Therefore, the usage is limited as it is.
[0023]
On the other hand, when the antenna 11 is bent as described above, the maximum reach is reduced to about 1/4, and the maximum reach is about 7 cm. Was considerably improved, and showed a reaching distance of less than 4 cm in the shortest case.
[0024]
As a result, even if the transmission unit 1 is incorporated into the product in a manner that cannot be distinguished from the outside, authentication can be performed.
[0025]
FIG. 5 shows another embodiment of the transmission unit.
[0026]
The difference from the structure of FIG. 3 is that only one side is turned up.
[0027]
FIG. 6 shows an example of a flap-equipped bag 100 in which the transmission unit 1 of the present invention is embedded. In FIG. 6, a part of the flap 104 is cut open so that the transmission unit 1 can determine it. The flap 104 basically receives no external load except for a triangular region connecting the vicinity of the clasp 105 and the vicinity of the joint of the bag portion 101. Further, the area slightly inside the corner of the flap 104 is hardly bent, and even if the transmitting unit 1 is built in, no problem occurs. The transmission unit 1 is sewn to the core 106 of the flap 104 with a sewing thread (not shown). Further, since the cover material 109 of the bag 100 is made of thick leather, even if the small and thin transmission unit 1 is sewn to the core material 106 of the flap, it is difficult to distinguish the presence of the transmission unit 1 from the appearance. . In addition, since the signal of the transmission unit 1 has a limited reach in which the directivity is relaxed, appropriate reception is possible at the time of reception based only on the approximate position where the transmission unit 1 is built in.
[0028]
Here, FIG. 7 shows how authentication is performed when authentication of the bag 100 is required. As described above, the transmission unit 1 is incorporated in the bag 100 in a state where it cannot be distinguished in appearance. When the receiver 30 is brought close to the bag 100 and a carrier signal is emitted from the receiver 30 as an electromagnetic wave, the transmission unit 1 transmits the encrypted unique ID information superimposed on the carrier wave of the receiver 30. The receiver 30 sends the received data to the encryption / decryption unit 31. The encryption / decryption unit 31 demodulates the encryption of the transmission unit 1 and performs another type of encryption, and then transmits the ID information to the public information line 33. It transmits to the authentication station 35 which is a base station via the base station. The base station specifies the history of the transmission unit 1, and encrypts information such as the product name and appearance characteristics of the product including the transmission unit 1, the manufacturer, and the manufacturing time by the information line 33. Reply with The decryption unit restores this information and displays it on the authentication information terminal 32. When the contents displayed on the authentication information terminal 32 match the characteristics of the bag 100 as a product, it is confirmed that the bag 100 is a legitimate product. It is difficult for an outsider to determine from the appearance that the transmission unit 1 is incorporated in the bag 100, and since the transmission unit 1 has a unique ID, the forged transmission unit is used. Even if a transmission unit 1 'collected from a similar product or another type of discarded product is incorporated in a counterfeit product, the authentication information does not match, so that it can be distinguished from a genuine product.
[0029]
The manufacturing method of the product and the authentication procedure up to this point are shown in the flowchart of FIG. In the chip manufacturing process 1000, individual authentication data is assigned to the semiconductor chip 10 in a non-rewritable state. On the other hand, the hoop material 20 having the shape including the antenna 11 is manufactured by the hoop material manufacturing process 1001. The two are integrated by a chip mounting step 1002 and connected by wires 12 in a connection step 1003. Thereafter, in a molding step 1004, a liquid resin is applied so as to cover the semiconductor chip 10 and the wires 12, and a general mold shape is obtained by temporary heating. Thereafter, main heating is performed in a heating step 1005 to completely solidify the mold 13, and further, the transmitting unit 1 is cut into individual states by a press cutting step 1006 to obtain the shape shown in FIG. In this state, the operation of the transmission unit 1 is confirmed, non-defective products are stocked, and stored until the product to be authenticated is determined.
[0030]
When the product to be certified is determined, the antenna 11 is bent into a desired bent shape (for example, the shape shown in FIG. 3) in the bending step 1008 of the transmitting unit 1 having the shape shown in FIG. Then, shipping 1009 is performed. At the same time, the authentication data input 1012 inputs the correspondence between the authentication data unique to the semiconductor chip 10 and the product to be authenticated, and the product name, model, history, date of manufacture, etc. of the product to be authenticated to the certificate authority 35. The product to be certified passes through the distribution 1010 to the final customer 1011. When an inquiry is made to the certification authority 35 by a person involved in the distribution 1010 and the final customer 1011, authentication data is sent from the certification authority, and additional information such as distribution history and product disposal information is input if necessary. .
[0031]
As described above, since the transmission unit 1 is small and deformable, it is easy to embed the same type of transmission unit 1 in various products. The mounting mode of another type of transmission unit 1 will be described with reference to FIG. The bag 100-1 has no flap and has a leather-wrapped ring-shaped handle. In this case, since the handle 103 is ring-shaped and the entire lower part of the handle 103 is sewn to the bag 101, the lower center of the handle 103 is less likely to receive an external load. Further, since the core material 106 is made of a reinforced resin, the transmission unit 1 is adhered to the core material 106 with an adhesive (not shown), fixed, covered with the surface material 109, and cannot be distinguished from the appearance. . At this time, since the transmission unit 1 is adhered to the core member 106 of the relatively thin ring-shaped handle 103, it is preferable that the antenna 11 be mounted with a slight curvature without bending. In this case, since the antenna 11 is not bent, the effect of reducing the directivity can hardly be expected. However, since the transmission unit 1 originally having the same shape as the bag 100 can be used, the transmission unit 1 is inexpensive due to the common use of parts. Can be kept.
[0032]
In the above examples, the transmission unit 1 is mounted on the flap or handle of the bag 100, but the mounting position of the transmission unit 1 can be changed depending on the form of the product to be authenticated. FIG. 9 illustrates the business bag 100-2. In the case of this product, a metal handle 103 and a clasp 105 are attached to the flap 104, and a core 106 'of the flap 104 is made of metal for reinforcement. Therefore, if the transmission unit 1 is incorporated in the flap 104, the signal is attenuated, which is not preferable. Therefore, in this embodiment, the transmission unit 1 is mounted at the lower corner of the bag 101. The core material 106 in this portion is made of leather like the surface material 109 and does not hinder signal transmission. In this case, the transmission unit 1 is formed by engraving a part of the core material 106 to provide a groove (not shown), and is fixed inside the groove by an adhesive.
[0033]
As described above, it is preferable to mount the antenna 11 with little or no bending. Other conditions include a case where the transmission unit 1 is integrally molded with a shaft portion of a stationery such as a fountain pen, a ballpoint pen, and a mechanical pencil, sunglasses, and fashion glasses. This applies to a case in which the transmitting unit 1 is built in a crane portion of a spectacle frame, such as a case where the transmitting unit 1 is mounted on an elongated component.
[0034]
As described above, there are various places where the transmission unit 1 is mounted. For example, in the case of a women's handbag made of a thin cloth having a soft surface or a wallet made of thin leather, the texture may be impaired when the transmitting unit 1 is arranged directly below the surface material. In such a case, the transmission unit 1 can be mounted at a position where the presence of the transmission unit 1 is difficult to recognize on the external appearance, such as by providing the transmission unit 1 on the back surface of the partition cloth of the internal accessory pocket.
[0035]
In the embodiments described above, the example in which the antenna 11 is formed substantially in a plane has been described. However, the bent form of the transmission unit 1 of the present invention is not necessarily limited to the plane. FIG. 10 shows the appearance of the transmission unit 1 in which the antenna 11 is bent out of the plane. Even in this case, the antenna 11 exhibits performance with reduced directivity.
[0036]
In the case of the portable lotion shown in FIG. 11, the cosmetic bottle 200 is made of transparent glass, and is not suitable for use in which the transmission unit 1 is built. On the other hand, the cap 201 has a small diameter because the cosmetics bottle 200 is a narrow-mouthed bottle, and it is difficult to incorporate the transmission unit 1 having the shape shown in FIG. In such a case, the problem is avoided by using the transmission unit 1 bent into the shape shown in FIG.
[0037]
FIG. 12A shows a cross-sectional shape of the cap 201. The cap 201 has a screw thread 206 on the inner surface. On the other hand, since the cap 201 is used for cosmetics, it is necessary to give priority to the aesthetic appearance and has a double structure. The outer cap 202 is a hard plastic cap designed to give priority to the appearance, and the inner cap 203 is a soft plastic having airtightness and durability of the screw thread 206. A square groove 205 is provided on the outer surface of the inner cap 203, and the communication unit 1 is fitted in the square groove 206. Further, the square groove 206 is slightly deeper on the upper surface of the inner cap 203, so that no problem occurs when the mold 13 of the communication unit 1 is stored. The communication unit 1 between the outer cap 201 and the inner cap 202 is filled with the resin 204 in the gap, and can be handled stably by being integrated.
[0038]
If the cap 201 has a different shape as shown in FIG. 12B, it can be easily coped with by changing the bending position of the antenna 11, and can be applied at a low cost to a change in cap design, a difference in product type, and the like. There is an advantage that expansion can be performed.
[0039]
In this application, since the antenna 11 is thin in the thickness direction of the cap 201, mounting is possible only by providing the shallow square groove 205 in the inner cap, and there is an advantage that the degree of freedom in designing the cap 201 can be increased.
[0040]
Depending on the structure of the cap, the antenna 11 of the transmission unit 1 may be easily mounted by rounding the end as shown in FIG. In this cap 201 ', the upper cap 202', which is the upper surface of the cap, is a separate piece in which the logo is embossed, and is manufactured separately from the tongue cap 203 ', which is the cap body. In this case, the portion of the square groove 205 that is in contact with the mold 13 is the same, but the tip from the bent portion of the antenna 11 is inserted into a thin deep hole 205 ′. It is the same that the resin 204 is filled and fixed. By changing the shape of the antenna 11 in the width direction in this way, a deep hole 205 ′ having a round cross-sectional shape can be used, so that it is possible to avoid difficulties in processing a square deep hole.
[0041]
According to the same method, products to be certified can be used not only for the products exemplified above but also for various products such as shoes, suits, jackets, belts, accessories, and key holders.
[0042]
In the above embodiment, the method of mounting the transmission unit 1 on the product itself requiring authentication has been described. However, according to a similar processing method, a quality display tag, a quality assurance tag, It is likewise possible to incorporate the transmission unit 1 in a special case that is sold as a unit with the product. In this case, the authentication transmission unit 1 can be used even when the product itself such as a watch or a jewelry is mainly made of metal having electromagnetic shielding properties. It goes without saying that since the product itself and these accessories are handled as a single unit at the distribution stage, there is no problem in certification, and there is an advantage that restrictions on the material and shape of the product itself are greatly eased. FIG. 3 shows a case where a member, such as a tag plate or a special case, in which the transmission unit 1 is to be housed is made of a plastic molded plate. The form in which the antenna is bent on a plane is particularly suitable, and the transmission unit 1 can be cast during molding of plastic. Since the transmitting unit 1 is small, the casting position can be selected relatively freely, and since the directivity of the antenna 11 is reduced, the positioning accuracy of the transmitting unit 1 can be reduced, so that there is an advantage that productivity is excellent.
[0043]
FIG. 15 shows another embodiment of the transmission unit 1 of the present invention. In this embodiment, the polyimide film 17 is formed on the back surface of the antenna 11 (the surface on which the semiconductor chip 11 is not mounted) at the stage of the hoop material 20. Since the polyimide film 17 has high heat resistance, it can withstand the heating in the mounting step of the semiconductor chip 10 and the connecting step of the wires 12 shown in FIG. In this case, the bending direction of the antenna 11 needs to bend the back side of the antenna 11 inward as shown in FIG. When the transmitting unit 11 is manufactured in this state, there is an advantage that the antenna 11 does not come into contact with each other at the bent portion of the antenna 11 because the polyimide film is formed on the bent portion of the antenna 11, so that transmission is stable.
[0044]
It is possible to form the polyimide film 17 on the chip mounting side or on both sides. In this case, the portion connecting the mounting portion of the semiconductor chip 10 and the wire 12 is masked so that the polyimide film is not formed. Must be used.
[0045]
Apart from this, there is also a method in which an insulating film is formed on the whole after obtaining the transmission unit 1 having the shape of FIG. In this case, since the transmitting unit 1 does not require a current connection to the outside and the step of heating at a high temperature has been completed, an inexpensive resin film such as a urethane resin can be used as the insulating film. In this case, when the antenna 11 is mounted on a cloth product, a leather product, or the like, there is an advantage that a problem that the antenna 11 is rusted due to wetness of the washing or the like can be avoided.
[0046]
【The invention's effect】
According to the present invention, the receiving sensitivity can be improved with one dipole antenna.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a schematic shape of a transmission unit before bending processing.
FIG. 2 is a perspective view illustrating a manufacturing process of the transmission unit.
FIG. 3 is a perspective view showing a schematic shape of a transmission unit.
FIG. 4 is a radar chart showing a signal reaching distance before bending of a transmission unit.
FIG. 5 is a radar chart showing a signal reaching distance after bending of the transmission unit.
FIG. 6 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 7 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 8 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 9 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 10 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 11 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 12 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 13 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 14 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 15 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 16 is a diagram showing a mounting example of a transmission unit and another embodiment.
FIG. 17 is a diagram showing another form of the transmission unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Transmission unit, 10 ... Semiconductor chip, 11 ... Antenna, 12 ... Wire, 13 ... Mold, 17 ... Polyimide film, 20 ... Hoop material, 21a ... Antenna part, 21b: Antenna part, 21c: Slit, 21d, 21e: Sprocket hole, 21f: Separation hole, 30: Receiver, 31: Encryption decryption unit, 32 ..Authentication information display terminal, 33 ... information line, 35 ... certificate authority, 100 ... bag, 101 ... bag, 102 ... strap, 103 ... handle, 104 ... Flap portion, 105: clasp, 106: core material, 109: front material, 200: cosmetic bottle, 201: cap, 202: outer cap, 203: inner cap , 204 ... resin, 205 - angular groove, 206 ... thread

Claims (3)

Having a flat dipole antenna and a semiconductor chip connected to the dipole antenna,
In a wireless authentication device that receives power and a signal from a radio wave received by the dipole antenna and outputs the power and signal by the dipole antenna,
The wireless authentication device, wherein the dipole antenna has the semiconductor chip folded at an angle deviated from a direction in which the dipole antenna extends. In claim 1,
A wireless authentication device, wherein the wireless authentication device is bent substantially 180 degrees in the normal direction. In claim 2,
The wireless communication device according to claim 1, wherein the dipole antenna is bent at an angle shifted by 90 degrees from a direction in which the dipole antenna extends.

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