JP2010062818A - Electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode which stabilizes the communication quality regardless of how a mobile terminal is carried. <P>SOLUTION: A signal electrode 11 is arranged along the inner side of a housing 20, which makes it possible to incorporate the signal electrode 11 inside a densely mounted personal digital assistant as well as to improve the communication quality during the use of the personal digital assistant. The signal electrode 11 has a U-shaped or arc-wise cross-sectional shape, which increases an area of close contact between the signal electrode 11 and a user when the user carries the personal digital assistant in a pocket, etc. and thereby stabilizes the communication quality of the personal digital assistant. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrode connected to an electric field communication device that induces an electric field based on information to be transmitted in an electric field transmission medium and detects the induced electric field to transmit and receive information.

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. Various devices are applied to the electrodes used in the electric field communication device in order to improve the transmission and reception performance (see, for example, Patent Document 1).
JP 2005-303922 A

  However, when an electric field communication device is mounted on a portable information terminal such as a mobile phone, it is difficult to newly incorporate a metal surface shape electrode of several centimeters for electric field communication in a high density mounted portable information terminal. There is a problem.

  Furthermore, in a planar antenna structure, the contact area between the human body, which is an electric field transmission medium, and the electrode differs depending on how the portable information terminal is held (for example, during operation), and the communication quality varies. There's a problem.

  The present invention has been made in view of the above, and an object of the present invention is to provide an electrode that is built into a portable information terminal and that stabilizes communication quality even when electric field communication is carried out during carrying and operation. It is in.

  An electrode according to a first aspect of the present invention is an electrode for electric field communication disposed inside a casing of a portable information terminal provided with electric field communication means for inducing electric field in an electric field transmission medium and performing electric field communication. It is arranged along the side of the body.

  In the present invention, by arranging the electrode along the side surface inside the housing, the user as the electric field transmission medium and the electrode are close to each other when the user operates the portable information terminal. As a result, communication quality can be stabilized.

  In the above electrode, the cross-sectional shape of the electrode is a U-shape or an arc shape.

  In the present invention, by making the cross-sectional shape of the electrode U-shaped or arcuate, not only when the user operates by holding the side of the portable information terminal, but also when wearing various ways Since the electrodes are close to the user, the communication quality can be stabilized.

  An electrode according to a second aspect of the present invention is a pair of electrodes for electric field communication arranged inside a casing of a portable information terminal provided with electric field communication means for inducing electric field in an electric field transmission medium and performing electric field communication. The pair of electrodes are arranged along the side surface of the housing.

  In the above electrode, the cross-sectional shape of each of the pair of electrodes is a U-shape or an arc shape.

  In the above electrode, one electrode of the pair of electrodes is disposed inside the other electrode.

  In the above electrode, when the electric field communication means performs transmission, one of the pair of electrodes is a signal electrode and the other electrode is a ground electrode. When the electric field communication means performs reception, the pair of electrodes is balanced. It is characterized by transmitting.

  In the present invention, a pair of electrodes are arranged along the side surface of the housing, and balanced transmission is performed by the pair of electrodes during reception, and one electrode is used as a signal electrode and the other electrode is used as a ground electrode during transmission. Unnecessary radiation can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, even when carrying out electric field communication at the time of carrying and operation, the electrode which stabilizes communication quality can be provided.

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

[First Embodiment]
FIG. 1 is a perspective view showing an outline of the configuration of an electrode in the first embodiment. The figure shows a configuration example of a case 20 of a box-type portable information terminal, and an electrode for electric field communication including a signal electrode 11 and a ground electrode 12. The signal electrode 11 and the ground electrode 12 are connected to an electric field communication device built in the portable information terminal. The electric field communication device induces an electric field in an electric field transmission medium such as a human body close to the signal electrode 11 and transmits data, and detects the electric field induced in the electric field transmission medium and receives data. The signal electrode 11 is arranged so as to go around the housing 20 along the side surface of the housing 20. Since the signal electrode 11 is disposed on the outer periphery of the housing 20 along the side surface, the ground electrode 12 is desirably disposed near the center inside the housing 20.

  FIG. 2 is a cross-sectional view of the electrode shown in FIG. As shown in the figure, the signal electrode 11 has a U-shaped cross section along the surface of the housing 20, and is disposed along the side surface of the housing 20. The side surface of the housing 20 is a surface other than the front surface and the back surface when the surface on which the display screen of the portable information terminal and the main operation buttons are disposed is the front surface, and the surface disposed facing the front surface is the back surface. It is. As shown in FIG. 3, the user 100 generally operates the front surface of the housing 20 toward the user, and therefore the side surface of the housing 20 has a natural shape for the user 100 to operate and use the portable information terminal. It is the surface to hold.

  FIG. 4 is an explanatory diagram illustrating a state in which the signal electrode 11 and the user 100 are close to each other when the user 100 holds the housing 20. When a user 100, who is an electric field transmission medium, operates a portable information terminal, the user 100 often operates with a side surface. As shown in FIG. 4, since the signal electrode 11 arranged along the side surface is close to the user 100, the electric field induced by the electric field communication device is more reliably induced in the user 100 or induced in the user 100. The received electric field can be received more reliably. By arranging the signal electrode 11 along the side surface, the signal electrode 11 and the user 100 are close to each other even when the user 100 has a corner of the housing. Further, by making the cross section of the signal electrode 11 U-shaped, the mobile information can be used when the user 100 operates the mobile information terminal by placing it on the palm of the hand, or when the mobile information terminal is stored in a pocket or the like. Even when the front and back surfaces of the terminal are in close contact with the user 100, the signal electrode 11 and the user 100 are close to each other, so that the communication quality can be stabilized.

  As shown in FIG. 5, the same effect as described above can be obtained even when the cross section of the signal electrode 15 is curved in an arc shape instead of the U shape. In addition, as shown in FIG. 6, even when the signal electrode 16 has a straight cross section and is disposed along the side surface of the housing 20, the communication quality when the user 100 operates the portable information terminal is improved. Is possible.

  In addition, as shown in FIG. 7, the signal electrode 11 is connected to the electric field communication device 50 with a closed loop structure, or the signal electrode 11 is connected to the electric field communication device 50 as an open loop structure as shown in FIG. Good. When the signal electrode 11 having an open loop structure is arranged in a case about the size of a mobile phone, the signal electrode 11 has a length that is about the same as a quarter wavelength of the UHF band. ) Antenna. The signal electrode 11 having a closed loop structure may be opened by a switch.

  Therefore, according to the present embodiment, by arranging the signal electrode 11 along the side surface inside the housing 20, the signal electrode 11 can be built in the portable information terminal mounted with high density. It is possible to improve the communication quality when using the portable information terminal.

  According to the present embodiment, the signal electrode 11 disposed on the side surface of the housing 20 has a U-shaped or arc-shaped cross section, so that the signal electrode 11 can be stored even when the portable information terminal is stored in a pocket or the like. The area where the user and the user are in close contact with each other increases, and the communication quality of the portable information terminal can be stabilized.

[Second Embodiment]
FIG. 9 is a perspective view showing an outline of the configuration of the electrode according to the second embodiment. The figure shows an example of the configuration of an electric field communication electrode comprising a housing 20 of a portable information terminal and a pair of electrodes 31 and 41. The electrodes 31 and 41 are arranged so as to be separated from each other in the vertical direction so as to go around the casing 20 along the side surface of the casing 20. As shown in the cross-sectional view of FIG. 10, each of the electrodes 31 and 41 has a U-shaped cross section.

  As shown in the schematic diagram of FIG. 11, the electrodes 31 and 41 are connected to a differential circuit 51, and the electrodes 31 and 41 have a role of balanced transmission of signals to the differential circuit 51 during reception. At the time of transmission, one of the electrodes 31 and 41 is a signal electrode and the other is a ground electrode. Thereby, unnecessary radiation can be suppressed. In the figure, the electrodes 31 and 41 have a closed loop structure, but may of course have an open loop structure.

  FIG. 12 shows a configuration of another electrode in the second embodiment. The pair of electrodes 32 and 42 shown in the figure are arranged such that the first electrode 32 goes around the housing 20 along the side surface, and the second electrode 42 is arranged along the inside of the first electrode. The The first electrode 32 and the second electrode 42 are concentrically spaced from each other.

  FIG. 13 shows a configuration of still another electrode in the second embodiment. The pair of electrodes 33 and 43 shown in the figure are arranged so that the first electrode 33 goes around the housing 20 along the side surface, and the second electrode 43 is wrapped by the first electrode 33. Arranged along the inside of the first electrode. The first electrode 33 and the second electrode 33 are concentrically spaced apart.

  Therefore, according to the present embodiment, the pair of electrodes 31 and 41 are arranged along the side surface of the housing 20 and have a function of balanced transmission of signals to the differential circuit 51 at the time of reception and one electrode at the time of transmission. By using as a signal electrode and the other electrode as a ground electrode, unnecessary radiation can be suppressed.

  Up to this point, an embodiment has been described in which electrodes are arranged on a box-shaped portable information terminal. A portable information terminal, in particular, a mobile phone, has a housing having various structures in addition to a box type. Typical examples include a folding type, a T-shape, an L-shape, or a slide type. The present invention can also be applied to housings of these various structures. Hereinafter, an embodiment in which the present invention is applied to a portable information terminal having a folding housing will be described.

  FIG. 14 is a schematic diagram in which the electrode according to the first embodiment is applied to a foldable housing. The portable information terminal shown in the figure is composed of two casings 20A and 20B, and can open and close the casings 20A and 20B around a hinge part (not shown) arranged on the left side of the figure. A display screen is arranged on the lower surface of the housing 20A in the figure, and an operation button is arranged on the upper surface of the housing 20B in the figure. The signal electrodes 11A and 11B are arranged along the respective side surfaces of the casings 20A and 20B so as to go around the casings 20A and 20B, and are connected to each other at the hinge portion. The ground electrodes 12A and 12B are disposed near the center inside the housings 20A and 20B.

  FIG. 15 is a schematic view in which the electrode according to the second embodiment is applied to a foldable housing. The configurations of the casings 20A and 20B are the same as those described with reference to FIG. The first and second electrodes 31A, 31B, 41A, and 41B are arranged concentrically along the side surfaces of the casings 20A and 20B so as to overlap vertically in the same figure, and the first electrode at the hinge portion. 31A and 31B and the second electrodes 41A and 41B are connected to each other.

  14 and 15, the electrodes are arranged in each of the two casings 20A and 20B. However, the electrodes may be arranged only on the side surface of the casing 20B having the operation buttons.

It is a perspective view which shows the structure of the electrode in 1st Embodiment. It is sectional drawing which shows the structure of the electrode in 1st Embodiment. It is a figure which shows a mode that a portable information terminal is utilized. It is a figure which shows a mode that a user and a signal electrode approach when a user has a portable information terminal. It is sectional drawing which shows the structure of another electrode in 1st Embodiment. It is sectional drawing which shows the structure of another electrode in 1st Embodiment. It is the schematic which shows the connection state of the electrode in 1st Embodiment. It is the schematic which shows the connection state of another electrode in 1st Embodiment. It is a perspective view which shows the structure of the electrode in 2nd Embodiment. It is sectional drawing which shows the structure of the electrode in 2nd Embodiment. It is the schematic which shows the connection state of the electrode in 2nd Embodiment. It is sectional drawing which shows the structure of another electrode in 2nd Embodiment. It is sectional drawing which shows the structure of another electrode in 2nd Embodiment. It is sectional drawing which shows the example which applied the electrode in 1st Embodiment to the foldable housing | casing. It is sectional drawing which shows the example which applied the electrode in 2nd Embodiment to the foldable housing | casing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 15, 16 ... Signal electrode 12 ... Ground electrode 20, 20A, 20B ... Housing 31, 41, 32, 42, 33, 43 ... Electrode 50 ... Electric field communication apparatus 51 ... Differential circuit 100 ... User 11A, 11B ... Signal electrodes 12A, 12B ... Ground electrodes 31A, 31B, 41A, 41B ... Electrodes

Claims (6)

An electrode for electric field communication disposed inside a housing of a portable information terminal provided with electric field communication means for inducing electric field in an electric field transmission medium and performing electric field communication,
An electrode arranged along a side surface of the housing.   2. The electrode according to claim 1, wherein the cross-sectional shape of the electrode is U-shaped or arcuate. A pair of electrodes for electric field communication disposed inside a casing of a portable information terminal provided with electric field communication means for inducing electric field in an electric field transmission medium and performing electric field communication,
The pair of electrodes are arranged along a side surface of the casing.   4. The electrode according to claim 3, wherein the cross-sectional shape of each of the pair of electrodes is U-shaped or arcuate.   The electrode according to claim 3 or 4, wherein one electrode of the pair of electrodes is disposed inside the other electrode.   When the electric field communication means performs transmission, one of the pair of electrodes is a signal electrode and the other electrode is a ground electrode, and when the electric field communication means performs reception, the pair of electrodes is balanced. The electrode according to claim 3, which transmits the electrode.

Images