JP4628438B2 - Electrode structure - Google Patents

Description

  The present invention relates to an electrode structure of an electric field communication apparatus that transmits data by inducing an electric field in an electric field transmission medium.

  There has been proposed an electric field communication device that induces an electric field in an electric field transmission medium such as a human body and performs data communication using the induced electric field (see Non-Patent Document 1).

In addition, in such an electric field communication device, it has been proposed that the communication electrode is in close contact with the human body, which is an electric field transmission medium, and the ground electrode is disposed at a position away from the communication electrode (see Patent Document 1).
JP 2004-128606 A "RedTacton", [online], Nippon Telegraph and Telephone Corporation, [Search January 10, 2008], Internet <URL: http://www.redtacton.com>

  As in the electric field communication device shown in FIG. 6, the contact degree with the human body is increased by making the communication electrode a strap type. FIG. 7 is a cross-sectional view of the electric field communication device 7 shown in FIG.

  An electric field communication device 7 shown in FIGS. 6 and 7 includes a casing 71 that houses a communication circuit 74, a strap-type communication electrode 72 that is disposed outside the casing 71, and a ground electrode that is disposed on the outer surface of the casing 71. 73. The communication circuit 74 is mounted on the circuit board 75 in the housing 71. The communication electrode 72 is connected to the input / output terminal of the communication circuit 74, and the ground electrode 73 is connected to the reference electrode (GND) of the communication circuit 74. The ground electrode 73 is made of a thin copper plate or the like and is covered with an insulating film.

  In FIG. 7, the user uses the electric field communication device 7 with the strap-type communication electrode 72 on the neck so that the upper casing 71 surface (the surface on which the ground electrode 73 is not disposed) is in contact with the body. .

  However, as shown in FIGS. 6 and 7, when the ground electrode 73 is disposed close to one surface of the housing, the electric field that returns from the human body to the ground electrode 73 when the surface on which the ground electrode 73 is disposed contacts the human body. There has been a problem that the communication quality is deteriorated.

  This invention is made | formed in view of the above, The place made into the subject is to suppress the fall of communication quality in the electric field communication apparatus which has a strap type | mold communication electrode.

  An electrode structure according to the present invention includes a housing, a strap-type communication electrode for electric field communication disposed outside the housing, and a ground electrode disposed in the center of the housing. To do.

  According to the present invention, in a communication device that transmits and receives data by inducing an electric field with respect to an electric field transmission medium such as a human body, a strap-type communication electrode is provided, and a ground electrode is disposed at a central portion in the housing Thus, it is possible to strengthen the coupling with the human body by the strap type communication electrode and to prevent the ground electrode 13 from approaching the human body, so that it is possible to suppress the deterioration of the communication quality.

  In the above electrode structure, the casing is a rectangular parallelepiped, and the ground electrode is disposed in the middle between two opposing surfaces having the largest area of the casing, and is a plate shape parallel to the surface. .

  In the present invention, for example, when the casing is a rectangular parallelepiped such as a card case, the ground electrode is arranged in the middle of the two opposing surfaces having the largest area, so that 2 The distance between the ground electrode and the human body can be maintained regardless of which of the two opposing surfaces comes into contact with the human body, so that deterioration in communication quality can be suppressed.

  In the above electrode structure, the housing and the ground electrode are cylindrical.

  In the above electrode structure, the casing is a polygonal column.

  ADVANTAGE OF THE INVENTION According to this invention, the fall of communication quality can be suppressed in the electric field communication apparatus which has a strap type communication electrode.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a configuration of an electric field communication device having an electrode structure in the present embodiment, and FIG. 2 is a cross-sectional view thereof.

  An electric field communication device 1 shown in FIGS. 1 and 2 includes a housing 11 that houses a communication circuit 14, a strap-like communication electrode 12 in a string shape disposed outside the housing 11, and a central portion in the housing 11. And the circuit board 15 disposed in the circuit board 15. Components constituting the communication circuit 14 are mounted on one side of the circuit board 15, and the solder surface opposite to the mounting surface is used as the entire ground, and the solder surface is used as the ground electrode 13. The communication electrode 12 is connected to an input / output terminal of the communication circuit 14, induces an electric field in the electric field transmission medium, receives an electric field induced in the electric field transmission medium, and supplies the electric field to the communication circuit 14. In order to prevent the ground electrode 13 from approaching a specific surface of the housing 11, the ground electrode 13 is arranged in the vicinity of the middle of two opposing surfaces having the largest area of the housing so as to be parallel to the surface. Is done. The strap-type communication electrode 12 is covered with an insulating film.

  The electric field communication device 1 is used with a strap-type communication electrode 12 hung on a user's neck or wrist, or with the user holding the communication electrode 12. The communication electrode 12 induces an electric field based on transmission data supplied from the communication circuit 14 to a human body that is an electric field transmission medium. In addition, an electric field induced in the electric field transmission medium is received and supplied to the communication circuit 14.

  As in the electric field communication device 1, the ground electrode 13 is disposed in the center of the housing 11 so that the ground electrode 13 and the housing 11 are spaced apart from each other, thereby preventing the ground electrode 13 from approaching the human body. it can. When the user hangs the strap-type communication electrode 12 on the neck, the ground electrode 13 does not come close to the user regardless of whether the upper or lower surface in FIG. The decrease can be suppressed.

  FIG. 3 is a perspective view showing a configuration of an electric field communication device including another electrode structure in the present embodiment, and FIG. 4 is a cross-sectional view thereof.

  The electric field communication device 5 shown in FIGS. 3 and 4 includes a cylindrical casing 51 that houses a communication circuit 54, a string-shaped strap-shaped communication electrode 52 disposed outside the casing 51, And a cylindrical ground electrode 53 disposed at the center of the structure. As in the electric field communication device 1 shown in FIGS. 1 and 2, the ground electrode 53 is arranged at the center of the housing 51 so that the ground electrode 53 and the housing 51 are spaced apart from each other. The communication circuit 54 is disposed inside the cylindrical ground electrode 53.

  Thus, by arranging the ground electrode 53 at the center of the casing 51, it is possible to suppress the ground electrode 53 from approaching the human body.

  The shape of the casing 51 is not limited to a cylindrical shape, and the cross section may be a polygonal column such as a hexagon or an octagon.

  In the electric field communication device 5, the communication circuit 54 is disposed inside the ground electrode 53. However, the communication circuit 54 may be mounted on the ground electrode 53 using a flexible substrate or the like.

  Next, electric field communication in which the electric field communication apparatus 1 according to the present embodiment performs communication by inducing an electric field in the electric field transmission medium will be described. FIG. 5 is a schematic diagram for explaining the mechanism of electric field communication. The figure shows a state of an electric field when information is transmitted from the left electric field communication device 1X to the right electric field communication device 1Y via the human body M which is an electric field transmission medium.

  First, the left electric field communication device 1X applies a voltage based on information to be transmitted to the right electric field communication device 1Y between its communication electrode 12X and the ground electrode 13X. Then, the path of the electric field returning to the communication electrode 12X through the communication electrode 12X of the electric field communication device 1X, the human body M, the communication electrode 12Y of the electric field communication device 1Y, the ground electrode 13Y, the ground, and the ground electrode 13X of the electric field communication device 1X. It is formed. The electric field communication device 1Y detects information by a voltage generated by an electric field induced between its own communication electrode 12Y and the ground electrode 13Y.

  When electric field communication is performed between the electric field communication device 1X and the electric field communication device 1Y, the efficiency of communication is improved as the electric field E1 returning from the human body M to the ground electrode 13X and the electric field E2 returning from the ground electrode 13Y to the human body M are smaller. it can.

  Therefore, according to the present embodiment, the ground electrodes 13 and 53 are arranged at the center of the casings 11 and 51 so that the ground electrodes 13 and 53 are separated from the surfaces of the casings 11 and 51, thereby Since it can prevent that 13 and 53 approach a human body, the fall of communication quality can be suppressed. In particular, when the strap-type communication electrodes 12 and 52 that are strongly coupled to the human body are provided, the ground electrodes 13 and 53 do not approach the human body regardless of which surface of the housings 11 and 51 contacts the human body. .

It is a perspective view which shows the structure of the electrode structure in one embodiment. It is sectional drawing which shows the structure of the electrode structure of FIG. It is a perspective view which shows the structure of another electrode structure in one Embodiment. It is sectional drawing which shows the structure of the electrode structure of FIG. It is a schematic diagram for demonstrating the structure of electric field communication. It is a perspective view which shows the structure of the conventional electrode structure. It is sectional drawing which shows the structure of the electrode structure of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 5, 7 ... Electric field communication apparatus 11, 51, 71 ... Housing | casing 12, 52, 72 ... Communication electrode 13, 53, 73 ... Ground electrode 14, 54, 74 ... Communication circuit 15, 75 ... Circuit board 1X, 1Y ... Electric field communication device 12X, 12Y ... Communication electrode 13X, 13Y ... Ground electrode

Claims (4)

A housing,
A strap-type communication electrode for electric field communication disposed outside the housing;
A ground electrode disposed in the center of the housing;
An electrode structure comprising: The casing is a rectangular parallelepiped,
2. The electrode structure according to claim 1, wherein the ground electrode is disposed in the middle of two opposing surfaces having the largest area of the casing and is in a plate shape parallel to the surface.   The electrode structure according to claim 1, wherein the casing and the ground electrode are cylindrical.   The electrode structure according to claim 1, wherein the casing is a polygonal column.

Images