JP2001109862A - Noncontact ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize mechanical damage to card constituent elements and to improve productivity by eliminating the need for capacitor capacity adjustment for resonance frequency setting of a resonance circuit of an antenna mechanism in a noncontact IC card. SOLUTION: The card has a flexible inlet of a sheet type resin material inside, resonance units are formed by arraying small plane coils patterned on the entire resin surface of the sheet type resin material and connecting capacitors in electrode structure penetrating the inlet resin between the top and reverse sides by the coils, and a large plane coil is formed surrounding the resonance unit group and connected to a noncontact IC chip; and the resonance frequencies of the respective resonance units are shifted to the frequency of a high-frequency electromagnetic field from a reader writer and frequencies above and below it and combined so that they do not interfere, thereby obtaining wide-band resonance characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contactless information medium, and more particularly, to office automation (Office A).
For information media such as IC cards used in the fields of automation, factory automation (FA), security, etc., power supply power and signal transmission / reception are electromagnetically coupled. The present invention relates to a non-contact IC card which is operated in a non-contact state without providing an electric contact on the IC card by a method.

[0002]

2. Description of the Related Art With the advent of an IC card having a built-in semiconductor memory or the like, the storage capacity has been dramatically increased as compared with a conventional magnetic card or the like. By itself having an arithmetic processing function, it has become possible to impart high security to an information medium.

An IC card is an ISO (International Orga)
In general, IC cards have a built-in IC such as a semiconductor memory in a card body made of plastic or the like, and are connected to an external read / write device on the surface of the card. Is provided with a metal conductive terminal, and the IC card is inserted into a card slot of the external read / write device for data communication between the IC card and the external read / write device. This is advantageous in applications requiring certainty and security of communication such as mass data exchange and settlement business, for example, credit and electronic wallet applications.

On the other hand, in application to gate management such as entry and exit, authentication is the main communication content, and the amount of communication data is often small, so simpler processing is desired. A technology devised to solve this problem is a contactless IC card. This is a DC power source that provides a space for vibration energy such as high-frequency electromagnetic fields, ultrasonic waves, and light in space, absorbs and rectifies the energy, and drives an electronic circuit built in the card. The frequency of the component is used as it is or is multiplied or divided to provide an identification signal, and the identification signal is transmitted to the information processing circuit of the semiconductor element via a coupler such as an antenna coil or a capacitor.

[0005] In particular, most non-contact IC cards for the purpose of authentication and simple counting data processing include a battery and a CPU (Cent
Radio authentication (Radio Frequency IDentifica) of hard logic without ral Processing Unit (Central Processing Unit)
tion. Hereinafter, this is simply referred to as RF-ID).
With the advent of this non-contact IC card, the security against forgery and tampering is increased as compared with the magnetic card, and the card carrier should approach the antenna unit of the read / write device attached to the gate device when passing through the gate,
All that is necessary is to touch the antenna of the read / write device with the carried card, and the complexity of data communication of removing the card from the case and inserting the card into the slot of the read / write device has been reduced.

The general structure of a non-contact IC card will be described below. Referring to FIG. 3, the non-contact IC card 1 has a non-contact IC chip 3 mounted on a plastic film formed by etching a metal film by a non-contact transmission mechanism including a planar coil 4 and a resonance capacitor 5. Thus, the inlet 6 is sealed in the card base material 2.

FIG. 4 shows an equivalent circuit of this non-contact IC card. A non-contact IC chip 3 is connected with a planar coil 4 and a resonance capacitor 5 in parallel.

In a non-contact IC card using a short wave band, the constant of a tuning circuit composed of a planar coil 4 and a resonance capacitor 5 must be accurately determined in order to obtain sufficient communication characteristics. However, the non-contact IC chip 3
And the formation of the resonance capacitor 5 using a plastic film causes large variations in the capacitance value in the manufacturing process.

Conventionally, in the manufacture of such a non-contact IC card, after the inlet 6 is manufactured, the conductor cutting portion 5c of the capacitance adjusting portion of the resonance capacitor 5 is cut by using a punch mechanism or the like, so that the resonance is performed. The capacitor 5 was trimmed and tuned. The capacitance value of the resonance capacitor at this time is the sum of the uncut capacitance values C0 to Cn in the equivalent circuit of FIG.

As a result, the quality of the card is adversely affected, for example, burrs are generated by the punch and the smoothness of the card is impaired. In addition, the adjustment of the capacitance of the resonance capacitor complicates the manufacturing process and raises the manufacturing cost.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is directed to an antenna mechanism comprising a planar coil and a capacitor sealed inside a card. The object of the present invention is to provide a non-contact IC card capable of eliminating the need for adjusting the capacitance of a capacitor for setting the resonance frequency of a resonance circuit, minimizing mechanical damage to card components, and improving productivity. And

[0012]

Means provided by the present invention to solve the above-mentioned problems include, as described in claim 1, transmission of information between a read / write device and information and power. A non-contact IC chip and an antenna mechanism that can be used in the case of performing non-contact transmission with the antenna, the antenna mechanism includes a small planar coil capable of receiving transmitted energy by electromagnetic induction, A plurality of resonance units each including a capacitor forming a resonance circuit are provided, and a large planar coil is arranged so as to surround the resonance unit. The non-contact IC chip is attached to the large planar coil. A non-contact IC card characterized in that:

According to a second aspect of the present invention, each resonance frequency of the plurality of resonance units is slightly higher or lower than a frequency required for transmitting information or transmitting information and power between the read / write device. , And the resonance frequency of the entire non-contact IC card is broadened.

With this configuration, even if the capacitance of the capacitor changes due to manufacturing variations of the card member, the resonance frequency of the entire non-contact IC card is broadened, so that the communication characteristics are not significantly affected. Without giving
There is no need to adjust the resonance capacitor.

More preferably, as set forth in claim 3, based on the invention according to claim 1 or 2, the capacitor is the same as a planar coil obtained by printed wiring on a non-contact IC card member. A non-contact IC card which is provided on a member and printed and wired in a pattern so that parallel plate electrodes for forming the capacitor face each other on both surfaces of the member.

With this configuration, a capacitor having a predetermined capacitance value can be formed without increasing the thickness of the entire card, and since it is integrated with a planar coil, the productivity is excellent.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure and basic principle of an antenna mechanism as a non-contact transmitting section according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a non-contact IC card according to the present invention, and FIG. 2 is a non-contact IC card according to the present invention.
It is sectional drawing of a C card.

The inlet 6 of the non-contact IC card 1 of the present invention is a flexible substrate made of a sheet-like resin material. A plurality of small planar coils 4b formed in a printed pattern on the surface of a sheet-like resin are arranged on almost the entire surface of the inlet 6.
b, a capacitor formed for each coil, that is, a sheet-shaped resin dielectric
It is connected to a capacitor 5 made of a parallel plate opposed to each other on the back side to form a resonance circuit. Then, it operates as a resonance unit 7 for receiving an electromagnetic wave radiated from a read / write device (not shown).

A large planar coil 4a is formed by a printed pattern so as to surround the arranged resonance units 7 group. Further, both ends of the coil 4a are formed as electrodes for connecting to the non-contact IC chip 3, and the non-contact IC chip 3 is mounted so as to be connected to this electrode.

The inlet 6 is sealed in the card base material 2 to form a card, the surface of which is subjected to processing such as printing and protection, etc.
It becomes C card 1. This carding means may be any of the injection molding method, the laminating method, the adhesive filling method, and other methods. Although vinyl chloride is used as the resin material of the inlet 6, polyimide, polycarbonate, PET, and the like can also be applied, and the material is not fixed to one kind. As the card base material, vinyl chloride was used, but any other material can be used as long as the card characteristics such as sufficient strength and durability can be obtained, such as polycarbonate.

Further, in order to manufacture a plurality of non-contact IC cards in the same process and to increase the manufacturing efficiency, a resin sheet in which a plurality of inlets are arranged and arranged is sealed with a card base material, and then a predetermined size is obtained. Non-contact I
It can be applied to the method of obtaining a C card.

Next, the operation of the antenna mechanism which is the non-contact transmitting section in the present invention will be described. First, a high-frequency electromagnetic field is induced in a transmitting / receiving antenna coil (not shown) by a high-frequency signal generated by a reading / writing device (not shown). Then, this high-frequency signal is radiated into space as electromagnetic energy.

At this time, when the non-contact IC card 1 in FIG. 1 is located in the high-frequency electromagnetic field, the non-contact IC chip 3 in the non-contact IC card 1 is generated by a high-frequency electromagnetic field generated by a transmitting / receiving antenna coil (not shown). And a plurality of small planar coils 4b arranged inside a large planar coil 4a to which
A high-frequency current flows through the resonance unit 7 including the capacitor 5 connected to the capacitor b. At this time, since the constant of the resonance circuit formed by the small planar coil 4b and the capacitor 5 is set so as to resonate sharply with the frequency of the high-frequency electromagnetic field radiated by the read / write device (not shown), the maximum electromagnetic energy can be received. Also, since this resonance unit (resonance circuit) forms a closed loop, the received energy exists as stored energy.

Each resonance unit 7 is a non-contact IC
Since the chip 3 is arranged close to the connected large planar coil 4a, the stored energy present in each resonance unit 7 is coupled to the planar coil 4a and sent to the non-contact IC chip 3. . Then, it is used as energy necessary for operating the non-contact IC chip 3.

Here, in the present invention, the small planar coil 4 is used.
b and the resonance frequency of each resonance unit 7 composed of the capacitor 5 connected to the coil 4b matches the frequency of a high-frequency electromagnetic field radiated from a read / write device (not shown), or slightly higher or lower frequency. Are combined so that they do not interfere with each other, and are constituted by several types of resonance units 7. Therefore, when looking at the resonance frequency characteristics of the antenna mechanism as the non-contact IC card 1 from the non-contact IC chip 3, the higher and lower frequencies are centered on the frequency of the high-frequency electromagnetic field radiated from the read / write device (not shown). , A broadband characteristic can be obtained.

Therefore, in the manufacturing process of the inlet 6, the capacitance and the like of the capacitor 5, which consists of a parallel plate opposed to the front and back sides via the dielectric material of the sheet-like resin serving as the inlet member, are caused to fluctuate. Contactless IC card 1 even if the resonance frequency of
As long as the range does not extremely deviate from the broadband resonance frequency characteristic viewed from the non-contact IC chip 3, communication with a not-shown read / write device will not be adversely affected.

In addition, by setting the resonance circuit constant of each resonance unit 7 in consideration of the maximum value and the minimum value of the capacitance variation of the capacitor 5 in the manufacturing process of the inlet 6, the capacitance variation in manufacturing the inlet is expected. By setting the broadband resonance frequency characteristics of the antenna mechanism as viewed from the non-contact IC chip 3, a non-contact IC card that can always obtain stable communication without worrying about manufacturing variations can be obtained.

[0028]

As is apparent from the above description, the non-contact IC card according to the present invention has a flexible inlet made of a sheet-like resin material inside, and the entire surface of the inlet is printed on the resin surface. A plurality of small planar coils formed in a pattern are arranged, and a capacitor having an electrode structure via the front and back surfaces of an inlet resin is connected to both ends of the planar coil for each coil to form a resonance unit. Have been. Further, another large planar coil is formed so as to surround the resonance unit group, and is connected to the non-contact IC chip.

Then, the resonance frequency of each resonance unit is
The one that matches the frequency of the high-frequency electromagnetic field radiated from the read / write device, the one that is slightly shifted up and down, etc.
Combine several types so that they do not interfere with each other.
The antenna mechanism viewed from the C chip obtains a broadband resonance characteristic. The received energy of each resonance unit is sent to the non-contact IC chip via a large planar coil surrounding the resonance unit group.

By adopting such a configuration, it is possible to manufacture a non-contact IC card which can always obtain stable communication characteristics without causing deterioration of communication with the read / write device due to variation in capacitance of the capacitor in the manufacturing process of the inlet.

Further, as in the conventional non-contact IC card manufacturing method, trimming tuning adjustment for cutting the capacitance adjusting portion of the resonance capacitor by using a punch mechanism or the like after manufacturing the inlet is not required. The process is simplified, productivity is improved, and production costs can be reduced.

Further, mechanical damage such as deterioration of card smoothness caused by burrs generated by the conventional punch mechanism is eliminated, and card quality in appearance is remarkably improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a non-contact IC card according to the present invention.

FIG. 2 is a sectional view of the non-contact IC card according to the present invention.

FIG. 3 is a schematic configuration diagram of a conventional non-contact IC card.

FIG. 4 is an equivalent circuit diagram of a conventional non-contact IC card.

[Explanation of symbols]

 1 Non-contact IC card 2 Card base material 3 Non-contact IC chip 4, 4a, 4b Planar coil 5 Capacitor 5a Main capacitor 5b Adjustment capacitor 5c Cutting part 6 Inlet 7 Resonance unit

Claims (3)

[Claims] An antenna mechanism and a non-contact IC chip which can be used when transmitting information or transmitting information and power to and from a read / write device in a non-contact manner, comprising: It is provided with a plurality of small planar coils capable of receiving transmitted energy by induction, and a plurality of resonance units each including a capacitor forming a resonance circuit with the planar coils, and further, a large planar coil is arranged surrounding the resonance units. A non-contact IC card, wherein the non-contact IC chip is attached to the large planar coil. 2. A non-contact IC card according to claim 1, wherein each resonance frequency of said plurality of resonance units is necessary for transmitting information or transmitting information and power to and from a read / write device. A non-contact IC card characterized by shifting the frequency slightly higher and lower than the frequency to broaden the resonance frequency of the entire non-contact IC card. 3. The non-contact IC card according to claim 1, wherein the capacitor is on the same member as a planar coil obtained by printed wiring on a non-contact IC card member, and is provided on both surfaces of the member. A non-contact IC card which is printed and wired in a pattern so that parallel plate electrodes for forming the capacitor face each other.