JP2005136838A - Wiring structure of antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide wiring structure of an antenna which is suitable for enhancing visibility to a user and simplifying a wiring pattern. <P>SOLUTION: The antenna 100 is constituted of a substrate 10, a loop antenna 12 formed on the substrate 10, a ground pattern 14 formed along the loop antenna 12 and four wiring patterns 16a to 16d for power supply formed adjacently to the ground pattern 14. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an RFID system that performs non-contact reading and rewriting of information with respect to an RFID (Radio Frequency IDentification) non-contact type IC tag, and in particular, improves visibility to a user and simplifies a wiring pattern. The present invention relates to an antenna wiring structure suitable for the above.

In recent years, IC cards equipped with IC chips are becoming widespread. This IC card can be classified into a contact type and a non-contact type according to a communication method between an IC chip built in the card and a reader / writer.
In the contact type, the contact point of the terminal provided on the surface of the card is brought into contact with the reader / writer to exchange data. Since the operating current of the IC card is supplied through the contact point, much power is consumed. There is an advantage that it can be performed even if it is necessary.

In contrast, the non-contact type (RFID) has no contact failure because there is no contact with the reader / writer, and data can be exchanged at a position several centimeters to several tens of centimeters away from the reader / writer. It has the advantage of being resistant to dirt, static electricity, etc., and has come to be used in various fields such as factory production management, logistics management, and entrance / exit management.
Conventionally, as an RFID system reader / writer antenna structure, for example, there is an RFID antenna disclosed in Patent Document 1.

  In the invention described in Patent Document 1, an antenna of an RFID system reader / writer is formed on a substrate having a two-layer structure, and a loop-shaped antenna pattern having one or more turns on the surface side of the substrate and an outer side of the loop antenna pattern. And a coplanar waveguide having a GND pattern arranged in parallel at a predetermined interval on the inner side, and on the back surface side, the outer edge substantially coincides with the outer edge of the outer surface GND pattern, and the inner edge is the surface. A GND pattern that substantially coincides with the inner edge of the inner GND pattern is formed.

Thereby, the electric field strength in the distance can be suppressed to a predetermined value or less without reducing the magnetic field in the vicinity due to the shielding effect of the GND pattern.
JP 2003-87044 A

  Some reader / writers of the RFID system are provided with an LED for displaying the state of the reader / writer (for example, whether reading or rewriting is possible), and this state display LED is provided on the main body substrate of the reader / writer. It is common that However, a user of an RFID system uses an IC card or the like in which an RFID non-contact type IC tag is embedded in close proximity to the reader / writer antenna, so it is not provided on the main body substrate of the reader / writer. The display is difficult to see and the reader / writer status is difficult to grasp. Therefore, from the viewpoint of improving the visibility for the user, it is desirable to provide the status display LED on the antenna side rather than on the main body substrate side of the reader / writer.

However, when the status display LEDs are provided on the antenna side in the invention described in Patent Document 1, two wiring patterns are required for each status display LED in addition to the ground pattern, so if a large number of status display LEDs are provided. There was a problem that the wiring pattern was complicated.
Therefore, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and is an antenna suitable for improving the visibility for the user and simplifying the wiring pattern. An object of the present invention is to provide a wiring structure.

[Invention 1] In order to achieve the above object, the antenna wiring structure of Invention 1 comprises:
A wiring structure of an antenna that performs communication using electromagnetic induction,
A loop antenna formed on the substrate;
A ground pattern formed along the loop antenna;
And a power supply wiring pattern formed adjacent to the ground pattern.

  As a result, since the power supply wiring pattern is formed adjacent to the ground pattern, it is possible to relatively easily attach the electronic element between them. Moreover, if a light emitting element such as an LED is attached as an electronic element, an effect that the visibility to the user can be improved as compared with the conventional case can be obtained. Further, when a plurality of power supply wiring patterns are provided, the ground pattern can be shared, so that the number of wirings does not increase so much and the effect that the wiring patterns become relatively simple as compared with the prior art can be obtained. It is done. Furthermore, the shield effect of the ground pattern also provides an effect that the electric field strength in the distance can be suppressed to a predetermined value or less without reducing the magnetic field in the vicinity.

Here, the ground pattern only needs to be formed along the loop antenna. For example, the ground pattern may be formed on the same surface as the surface on which the loop antenna is formed on the substrate surface. It may be formed on the opposite surface or may be formed in the substrate.
The power supply wiring pattern may be formed adjacent to the ground pattern. For example, the power supply wiring pattern may be formed on the surface of the substrate on which the loop antenna is formed, or opposite to the surface. It may be formed on the surface of the substrate or may be formed in the substrate. Further, it may not be formed on the same surface as the ground pattern, but is preferably formed on the same surface as the ground pattern from the viewpoint of facilitating the mounting of the electronic element.

The antenna structure according to the present invention can be applied as an RFID reader / writer antenna, an RFID non-contact IC tag antenna, and other antennas.
[Invention 2] Furthermore, the antenna wiring structure of Invention 2 is the antenna wiring structure of Invention 1,
The ground pattern is formed on either the same surface as the surface on which the loop antenna is formed or the surface opposite to the surface of the substrate surface,
The power supply wiring pattern is formed on the same surface of the substrate surface as the surface on which the ground pattern is formed.

Thereby, the effect that an electronic element can be attached more easily between the power supply wiring pattern and the ground pattern is obtained.
[Invention 3] Furthermore, the wiring structure of the antenna of Invention 3 is the wiring structure of the antenna of Invention 2,
A connection terminal for connecting one end of an electronic element connected between the power supply wiring pattern and the ground pattern is formed at an end of the power supply wiring pattern.

Thereby, when attaching an electronic device, one end of the electronic device may be connected to the connection terminal and the other end may be connected to the ground pattern. Therefore, an effect is obtained that an electronic element can be more easily attached between the power supply wiring pattern and the ground pattern.
[Invention 4] Further, the antenna wiring structure of Invention 4 is the antenna wiring structure of Invention 3,
A plurality of power supply wiring patterns;
The connection terminals of the power supply wiring patterns are arranged so as to surround the loop antenna.

  Thereby, when a light emitting element such as an LED is attached as an electronic element and light is emitted, the periphery of the loop antenna emits light, and the user can grasp the effective range of wireless communication by the light emission of the light emitting element. . Therefore, when applied to the RFID system, the user can relatively reliably approach the RFID non-contact type IC tag within the effective range of wireless communication, so that reading or rewriting errors can be expected to be reduced. An effect is obtained.

[Invention 5] Furthermore, the antenna wiring structure of Invention 5 is the antenna wiring structure of Invention 4,
Each of the power supply wiring patterns is characterized in that the distance from the base portion to the end portion is smaller as the distance from the ground pattern is smaller.
Thereby, when an electronic element is attached between the ground pattern and the power supply wiring pattern, the electronic element does not straddle another power supply wiring pattern. Therefore, an effect that the electronic element can be attached relatively reliably is obtained.

[Invention 6] Further, the antenna wiring structure of Invention 6 is the antenna wiring structure of any one of Inventions 3 to 5,
The electronic element is a light emitting element.
Thereby, if a light emitting element is attached, the effect that the visibility with respect to a user can be improved compared with the former is acquired.

[Invention 7] Furthermore, the wiring structure of the antenna of Invention 7 is the wiring structure of the antenna of any one of Inventions 1 to 6,
The present invention is characterized by being applied as an antenna for reading or rewriting information with respect to an RFID non-contact type IC tag.
Thereby, since it is applied as an antenna of the reader / writer of the RFID system, an effect that the visibility to the user can be improved as compared with the conventional case is obtained.

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are diagrams showing an embodiment of an antenna wiring structure according to the present invention.
In this embodiment, the antenna wiring structure according to the present invention is applied as an antenna 100 of a reader / writer of an RFID system as shown in FIG.
First, the configuration of the antenna 100 according to the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a plan view of the antenna 100.
As shown in FIG. 1, the antenna 100 is formed adjacent to the substrate 10, the loop antenna 12 formed on the substrate 10, the ground pattern 14 formed along the loop antenna 12, and the ground pattern 14. And four power supply wiring patterns 16a to 16d.

A ground pattern 14 is formed outside the loop antenna 12 along the loop antenna 12.
On the outer right half of the ground pattern 14, power supply wiring patterns 16 a and 16 b are formed adjacent to the ground pattern 14. The inner power supply wiring pattern 16a having a small distance from the ground pattern 14 is wired from the base 18 to the lower right along the ground pattern 14 with the base 18 as a base 18 in the counterclockwise direction. On the other hand, the outside power supply wiring pattern 16b having a large distance from the ground pattern 14 is wired from the base 18 along the ground pattern 14 counterclockwise to the upper right. Therefore, the distance from the base 18 to the end of the power supply wiring pattern 16a is smaller than that of the power supply wiring pattern 16b.

  On the outer left half of the ground pattern 14, power supply wiring patterns 16 c and 16 d are formed adjacent to the ground pattern 14. The inner power supply wiring pattern 16 c having a small distance from the ground pattern 14 is wired from the base portion 18 to the lower left in the clockwise direction along the ground pattern 14. On the other hand, the outside power supply wiring pattern 16 d having a large distance from the ground pattern 14 is wired from the base 18 to the upper left along the ground pattern 14 in the clockwise direction. Therefore, the distance from the base 18 to the end of the power supply wiring pattern 16c is smaller than that of the power supply wiring pattern 16d.

In addition, connection terminals 20a to 20d for connecting one end of the LED are formed at the ends of the power supply wiring patterns 16a to 16d, respectively. Since the connection terminals 20a to 20d are located at the lower right, upper right, lower left and upper left of the loop antenna 12, respectively, the connection terminals 20a to 20d are arranged to surround the loop antenna 12.
FIG. 2 is a cross-sectional view taken along line AA ′ in FIG.

As shown in FIG. 2, the ground pattern 14 and the power supply wiring patterns 16 a to 16 d are formed on the same surface of the substrate 10 as the surface on which the loop antenna 12 is formed.
FIG. 3 is a plan view of the antenna 100 to which the LEDs 22a to 22d are attached.
As shown in FIG. 3, four LEDs 22 a to 22 d are attached to the antenna 100 while sharing the ground pattern 14.

The LED 22 a is attached with one end connected to the connection terminal 20 a and the other end connected to the ground pattern 14. The LED 22 b is attached with one end connected to the connection terminal 20 b and the other end connected to the ground pattern 14.
The LED 22 c is attached with one end connected to the connection terminal 20 c and the other end connected to the ground pattern 14. The LED 22d is attached with one end connected to the connection terminal 20d and the other end connected to the ground pattern.

A harness 24 for connecting to a lead / writer substrate (not shown) is attached to both ends of the loop antenna 12.
FIG. 4 is a cross-sectional view showing a case where the antenna 100 is attached to the inside of the housing 30.
When attaching the antenna 100 to the inside of the housing 30, as shown in FIG. 4, a through hole 32 a is formed in the housing 30 corresponding to the LED 22 a, the LED 22 a is projected from the through hole 32 a, and the back surface of the substrate 10 is The caulking member 34 is caulked. The same applies to the mounting structure of the LEDs 22b to 22d.

Thus, in this embodiment, the loop antenna 12 formed on the substrate 10, the ground pattern 14 formed along the loop antenna 12, and the power supply for power supply formed adjacent to the ground pattern 14. The wiring patterns 16a to 16d are configured.
Accordingly, since the power supply wiring patterns 16a to 16d are formed adjacent to the ground pattern 14, the LEDs 22a to 22d can be attached between them relatively easily. Moreover, if LED22a-22d is attached to the antenna 100, the visibility with respect to a user can be improved compared with the past. Furthermore, since the ground pattern 14 can be shared, the number of wirings does not increase so much and the wiring pattern becomes relatively simple as compared with the conventional case. Further, the shielding effect of the ground pattern 14 can suppress the electric field strength in the distance to a predetermined value or less without reducing the magnetic field in the vicinity.

Furthermore, in the present embodiment, the power supply wiring patterns 16a to 16d are formed on the same surface of the substrate 10 as the surface on which the ground pattern 14 is formed.
Thus, the LEDs 22a to 22d can be more easily attached between the power supply wiring patterns 16a to 16d and the ground pattern 14.
Further, in the present embodiment, connection terminals 20a to 20d for connecting one ends of the LEDs 22a to 22d are formed at the ends of the power supply wiring patterns 16a to 16d.

Thereby, when attaching LED22a-22d, what is necessary is just to connect one end of LED22a-22d to connection terminal 20a-20d, and connect the other end to the ground pattern 14. FIG. Therefore, the LEDs 22a to 22d can be more easily attached between the power supply wiring patterns 16a to 16d and the ground pattern 14.
Further, in the present embodiment, the connection terminals 20 a to 20 d are arranged so as to surround the loop antenna 12.

  Thereby, when LED22a-22d is attached and made to light-emit, the circumference | surroundings of the loop antenna 12 light-emit, and the user can grasp | ascertain the effective range of wireless communication by light emission of LED22a-22d. Therefore, the user can relatively reliably approach the RFID non-contact type IC tag within the effective range of wireless communication, so that it can be expected that reading or rewriting errors are reduced.

Further, in the present embodiment, each of the power supply wiring patterns 16a to 16d has a smaller distance from the base 18 to the end as the distance from the ground pattern 14 is smaller.
Thereby, when attaching LED22a-22d, LED22a-22d does not straddle other wiring patterns 16a-16d for power supply. Therefore, the LEDs 22a to 22d can be attached relatively reliably.

In the said embodiment, LED22a-22d respond | corresponds to the electronic element of the invention 3 or 6, or the light emitting element of the invention 6.
In the above embodiment, the ground pattern 14 and the power supply wiring patterns 16a to 16d are formed on the same surface of the substrate 10 as the surface on which the loop antenna 12 is formed. Not limited to this, it can also be configured as shown in FIG.

FIG. 5 is a cross-sectional view taken along the line AA ′ in FIG.
As shown in FIG. 5, the ground pattern 14 and the power supply wiring patterns 16a to 16d are formed on the surface of the substrate 10 opposite to the surface on which the loop antenna 12 is formed.
Moreover, in the said embodiment, although LED22a was protruded from the through-hole 32a and the antenna 100 was attached to the inner side of the housing | casing 30, it can also comprise not only this but as shown in FIG.

FIG. 6 is a cross-sectional view showing the case where the antenna 100 is attached to the inside of the housing 30.
When the antenna 100 is attached to the inside of the housing 30, as shown in FIG. 6, a through hole 32 a is formed in the housing 30 corresponding to the LED 22 a, and the LED 22 a is faced partway through the through hole 32 a. A transparent sheet 36 is formed thereon. The same applies to the mounting structure of the LEDs 22b to 22d.

Moreover, in the said embodiment, although lighting control of LED22a-22d was not demonstrated especially, it is preferable to control LED22a-22d so that it may light sequentially.
Thereby, compared with the case where LED22a-22d is lighted all at once, power consumption can be reduced.
Moreover, in the said embodiment, although the board | substrate 10 was not demonstrated especially, as a board | substrate 10, a flexible type board | substrate can also be used.

  In the above embodiment, the antenna wiring structure according to the present invention is applied as the antenna 100 of the reader / writer of the RFID system as shown in FIG. 1, but the present invention is not limited to this. The present invention can be applied to other cases without departing from the scope.

1 is a plan view of an antenna 100. FIG. It is sectional drawing along the A-A 'line | wire in FIG. It is a top view of the antenna 100 which attached LED22a-22d. 4 is a cross-sectional view showing a case where the antenna 100 is attached to the inside of the housing 30. FIG. It is sectional drawing along the A-A 'line | wire in FIG. 4 is a cross-sectional view showing a case where the antenna 100 is attached to the inside of the housing 30. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Board | substrate, 12 ... Loop antenna, 14 ... Ground pattern, 16a-16d ... Wiring pattern for power supply, 18 ... Base part, 20a-20d ... Connection terminal, 22a-22d ... LED, 24 ... Harness, 30 ... Housing, 32a ... through hole, 34 ... caulking member, 36 ... transparent sheet

Claims (7)

A wiring structure of an antenna that performs communication using electromagnetic induction,
A loop antenna formed on the substrate;
A ground pattern formed along the loop antenna;
An antenna wiring structure comprising: a power supply wiring pattern formed adjacent to the ground pattern. In claim 1,
The ground pattern is formed on either the same surface as the surface on which the loop antenna is formed or the surface opposite to the surface of the substrate surface,
The antenna wiring structure, wherein the power supply wiring pattern is formed on the same surface of the substrate surface as the surface on which the ground pattern is formed. In claim 2,
The antenna is characterized in that an end of the power supply wiring pattern is formed with a connection terminal for connecting one end of an electronic element connected between the power supply wiring pattern and the ground pattern. Wiring structure. In claim 3,
A plurality of power supply wiring patterns;
An antenna wiring structure, wherein the connection terminals of the power supply wiring patterns are arranged so as to surround the loop antenna. In claim 4,
Each of the power supply wiring patterns has a smaller distance from the base to the end as the distance from the ground pattern is smaller. In any of claims 3 to 5,
The wiring structure of an antenna, wherein the electronic element is a light emitting element. In any one of Claims 1 thru | or 6.
An antenna wiring structure characterized by being applied as an antenna for reading or rewriting information with respect to an RFID non-contact type IC tag.

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