JP3489649B2 - Electromagnetic shielding blind - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blind having electromagnetic shielding performance.

[0002]

2. Description of the Related Art The need for electromagnetic shielding of buildings is indispensable in the case where a personal portable device to which radio technology is applied is utilized indoors within the legally prescribed frame, and the security of information is also required. Therefore, it is necessary to block radio waves of the relevant frequency, that is, prevent radiation and intrusion.

As an electromagnetic shield for a building structure, conventionally, each floor surface can be sufficiently electromagnetically shielded by an iron plate or the like, and a metal foil or a metal mesh is added to the partition between the external wall surface and the tenant, which is effective even in the microwave band. Electromagnetic shielding can be performed.

On the other hand, when an opening such as a window is provided,
It is difficult to secure electromagnetic shielding performance, and the glass window is made to have an electromagnetic shielding function by using glass with mesh or glass with a conductive film attached. As an example, if an extremely thin vapor-deposited film of tungsten, aluminum, etc. is laminated on the entire surface of the glass or inside the glass, the reduction of visible light will be only 30-35%. 1.
It is known that the maximum attenuation is 20 to 30 dB for 9 GHz) or wireless LAN (2.45 GHz).

[0005]

However, with this method, it is possible to block radio waves from the outside without impairing the feeling of openness of the building with daylight, but it is not effective when the window is opened. Moreover, it does not have frequency selectivity and blocks radio waves other than the target frequency.

[0006] As a result, as the intruding radio waves from the outside are cut off, even the electric waves of public important information such as broadcast waves of pagers, mobile phones, FMs, radios, etc. used inside and outside the building are cut off. However, it may cause interference with the reflection of TV radio waves. Furthermore, in practical use, it is necessary to maintain electrical contact without any gap including the window frame.

On the other hand, in Japanese Patent Laid-Open No. 2-16283,
As an electromagnetic shielding blind, a pleated type with a metal foil or conductive film attached to form an electromagnetic shielding layer is also presented, but this also does not have frequency selectivity and blocks radio waves other than the target frequency. What happens is the same as in the case of the window glass. Moreover, in practical use, the blade is continuous even though it is folded back, and it is also necessary to maintain electrical contact without a gap including the frame, as in the case of the window glass, along the vertical frame guide liner. The balance member of the blade moves up and down while always contacting through the guide piece.

The object of the present invention is to eliminate the disadvantages of the conventional example, to enable electromagnetic shielding by selecting only the radio waves of the required frequency, and to affect the continuity between members and the shield performance of the connecting portion. Moreover, since it is not necessary to consider the grounding countermeasure, it is possible to freely set the electromagnetic shielding blind, which is convenient.

[0009]

In order to achieve the above-mentioned object, the present invention firstly provides an electromagnetic wave having a patterned Y-shaped linear antenna on a light-shielding plate or light-shielding film constituting a blind. Considering the field absorption equivalent area ,
In addition, linear antennas whose ends extending in three directions are adjacent to each other
The antennas are arranged regularly so as to approach the central intersection of the second antenna. Secondly, the linear antenna has a Y-shaped first antenna, and a white frame character surrounding the second antenna as the second antenna. The gist of the invention is to form a composite antenna in combination with the Y-shaped antenna.

According to the first aspect of the present invention, in the linear antenna as a line pattern provided on the film, not only the area of the antenna metal portion reflects electromagnetic wave energy, but also the electromagnetic field near the antenna metal surface. Also has a reflective effect. The absorbed electromagnetic field is also absorbed as heat loss due to propagation in the linear antenna.Therefore, if this film is attached to a plate such as a wall plate, glass, or ceiling plate, electromagnetic shielding can be easily performed. The function is obtained.

Further, because of the shielding effect due to the reflection loss and the absorption loss due to the linear antenna, it is not necessary to electrically connect the antenna to the air conditioning duct or the like.
The setting is not limited to conductive connection, and can be set freely. Especially, since it can be attached to existing glass etc. as a film,
An electromagnetic shielding function can be easily added to an existing window glass or the like without replacing it.

Further, although the surface of the actual radio wave has various inclinations instead of a horizontal row, the linear antenna having a Y shape can be applied to radio waves having different inclinations other than the horizontal plane.

According to the second aspect of the present invention, in addition to the above-mentioned action, a Y-shaped member and a Y-shaped frame character surrounding the Y-shaped member are provided.
By using a composite antenna in combination with a letter-shaped antenna, antennas capable of blocking a plurality of specific frequencies can be arranged on the same plane.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 show a first embodiment of an electromagnetic shielding blind according to the present invention, which is a blind having a slat 1.

In the present invention, as shown in FIG. 3, a small Y-shaped linear antenna 5 as a line pattern is provided on the surface of the slat 1 as a light shielding plate which constitutes a blind, and the electromagnetic field absorption equivalent area of this antenna is taken into consideration. And arranged regularly.

Slat 1 is vinyl chloride, polyethylene,
Although a synthetic resin plate such as polypropylene is used, as a method for regularly arranging the patterned small linear antennas 5 on the slats 1, silk printing,
A method such as pattern pressure bonding and sticking with a film can be considered.

The sticking with this film is carried out by sticking a synthetic resin film such as a polyimide film, a polyester film or a polyethylene film provided with the linear antenna 5 as a line pattern by an etching method, a laminating method or a screen printing method. Is also possible.

The etching method is the same method as a general printed circuit board in which a film as a flexible substrate, to which a copper foil is attached, is used as a base material, a pattern portion is masked and the remaining portion is dissolved with a solvent. . On the other hand, in the screen printing method, a circuit pattern is formed by printing a metal paste such as silver, copper or gold on a base material.

In order to protect the linear antenna 5, a cover film or coating may be applied on it.

First, the basic principle related to the present invention will be described. When the conductor piece 3 is in the air as shown in FIG. 4, when a radio wave is incident on this surface, one part passes through and the other part is reflected. In this case, the attenuation amount of the transmitted wave passes through the 4,6 GHz band but does not pass through the 12,14 GHz band as shown in FIG. Such characteristics differ depending on the shape of the conductor piece 3.

If the conductor piece 3 is a linear antenna (dipole), a part of the absorbed (received power) is re-radiated, and 1/4 of the power is received by the linear antenna (conductor).
Absorbed as heat loss.

As shown in FIG. 6, the half-wavelength (1/2) linear antenna placed parallel to the plane magnetic field does not receive electromagnetic wave energy only in the area of the metal part of the antenna, but in the vicinity of the metal surface. Is absorbing the electromagnetic field of. Although the spread is not uniform, the calculated value of the equivalent area Ae is displayed by the following formula 1.

[0023]

[Equation 1] Ae≈0.13λ ²

If such linear antennas 4 are arranged on the slats 1 according to the equivalent area Ae as shown in FIG. 7, the same effect as if a metal film is pasted is exhibited.

By the way, 1885 to 1950 MHz is used for the current personal communication (PHS-JAPAN., PCS-US.DECT-Europe) and FPLMTS (Future Public Land) which has been in practical use since the year 2000.
Mobile Telephone System) frequency band, 2420
~ 2480MHz is the ISM (Industrial-Sci) specified by ITU
entific-Medical --- Industrial, scientific, medical frequencies are assigned to wireless LANs in buildings, and are also used in microwave ovens and high-power linear accelerators for nondestructive inspection.

In the case of PHS, the wavelength is λ = 153 mm, wireless L
In the case of AN, since λ = 122 mm, the area of each linear antenna 4 is Ae = 3043 mm ^{2 at} PHS, Ae = 1935 mm
² atLAN, which may be scattered on the slats 1 in consideration of the electromagnetic field absorption equivalent area Ae.

However, the arrangement of the linear antennas 4 in a horizontal row as shown in FIG. 7 cannot cope with the fact that the wavefront of an actual radio wave is not in a horizontal row and thus has various inclinations. Therefore, in this embodiment, the linear antennas 5 are Y-shaped as shown in FIG. 3, and the linear antennas 5 are arranged so that the ends extending in the three directions approach the central intersections of the adjacent linear antennas 5.

The reason why the shape is Y-shaped in this way is to correspond to the plane of polarization of radio waves, and if it is extended in three directions,
Even if the wave surface of the radio wave has any inclination, it resonates with either one, so that it can be applied to radio waves having different inclinations other than the horizontal plane.

Further, when the blind is closed, the slats 1 are oriented vertically, and the upper and lower slats overlap each other, so that an electromagnetic shielding effect can be obtained as a large surface without a gap. Further, the Y-shaped linear antenna 5 is a gathering surface of a plurality of slats 1 when such a blind is closed,
It suffices to form a pattern that forms a continuous array.

Further, the linear antenna 5 is 1885 to 1950 MH.
If the slats 1 are provided with different lengths so as to cut off the two frequency bands of z and 2420 to 2480 MHz, other pagers (275 to 364 MH)
z), mobile phones (810 to 940 MHz, 1477 to 1501 MH
z), FM broadcasting (76 to 90 MHz), medium wave radio broadcasting (52
It does not block even the radio waves of important public information such as broadcast waves (6 to 1600 kHz).

As another embodiment, as shown in FIG.
Λ / (4√ε) Y-shaped first linear antenna 5a with a side of 2450 MHz and a thin copper wire (0.2 φ) with a circumference of λ / √ε of 1950 MHz surrounds it. You may form the composite linear antenna 5 by combining with the Y-shaped 2nd linear antenna 5b. The shape of the Y-shape is used in order to deal with the polarization plane of the radio wave, and the first linear antenna 5a and the second linear antenna 5b are formed.
The reason for combining is to correspond to two frequencies.

As described above, it is required that the first linear antenna 5a and the second linear antenna 5b do not directly intersect each other as shown in FIG. 8, but a non-conductive layer such as a non-conductive film is used. If they are interposed, they can be arranged one above the other.

FIG. 9 shows a second embodiment of the present invention, in which the blinds are roll blinds.

As is well known, the roller blind is of a shutter type in which a sheet 8 as a light-shielding film can be pulled out from a storage starter 6 having a mounting substrate 7 formed on the upper surface. Small Y-shaped linear antennas 5 as patterns were periodically arranged in consideration of the electromagnetic field absorption equivalent area of this antenna.

Although the linear antenna 5 is made of metal,
The sheet 8 is provided by a method such as silk printing, weaving using metal fibers, film sticking, pattern pressure bonding, printer printing, or the like. Among these, for printing on a printer, use of a conductive ribbon, use of a plotter, use of metal ink, and the like can be considered.

Further, although not shown as another embodiment, a case where the linear antennas 5 are arranged on the vertical slats by a vertical blind in which vertically oriented slats are arranged side by side, or in Japanese Patent Laid-Open No. 2-16283. There is a case where the linear antennas 5 are arranged on the blade with a pleat type blind formed by folding back such a blade.

[0037]

As described above, the electromagnetic shielding blind of the present invention exhibits the electromagnetic shielding effect, and it is possible to perform electromagnetic shielding by selecting only the radio wave of the required frequency and continuously connecting each member. Since it does not need to take into consideration the influence of the connection performance on the shield performance of the connection part and the grounding measures, it can be set freely and is convenient.

[Brief description of drawings]

FIG. 1 is a perspective view of essential parts showing a first embodiment of an electromagnetic shielding blind of the present invention.

FIG. 2 is a front view showing the first embodiment of the electromagnetic shielding blind of the present invention.

FIG. 3 is a partial plan view of the slats of the electromagnetic shielding blind of the present invention.

FIG. 4 is a perspective view showing an electromagnetic shield principle of a board having an electromagnetic shield performance of the present invention.

FIG. 5 is a graph showing an example of frequency response in the case of FIG.

FIG. 6 is an explanatory view when a conductor is a linear antenna (dipole).

FIG. 7 is a partial plan view of a slat in which a linear antenna is arranged.

FIG. 8 is a front view showing an example of a composite linear antenna.

FIG. 9 is a perspective view of a roller blind.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Slat 3 ... Conductor piece 4 ... Linear antenna 5 ... Linear antenna 5a ... 1st linear antenna 5b ... 2nd linear antenna 6 ... Storage starting part 7 ... Mounting board 8 ... Sheet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masaaki Sasada               2-8-57 Sakasegawa Takarazuka-shi, Hyogo International Information               Information Science Research Foundation (72) Inventor Yoshimasa Yoshimasa               1-3-15 Awaza, Nishi-ku, Osaka City, Osaka Prefecture                 Kashima Construction Co., Ltd. Kansai Branch (72) Inventor Kazushi Yamanoue               1-3-15 Awaza, Nishi-ku, Osaka City, Osaka Prefecture                 Kashima Construction Co., Ltd. Kansai Branch (72) Inventor ▲ Taka ▼ Shuichi Saka               Deer, 2-1-1, Tobita, Chofu-shi, Tokyo               Shima Construction Co., Ltd. Technical Research Center (72) Inventor Junichi Hirai               Deer, 2-1-1, Tobita, Chofu-shi, Tokyo               Shima Construction Co., Ltd. Technical Research Center                (56) References Japanese Patent Laid-Open No. 2-16283 (JP, A)                 JP-A-8-274538 (JP, A)                 JP-A-8-330783 (JP, A)

Claims (2)

(57) [Claims] 1. A light shielding plate or the light-shielding film constituting the blind, in consideration of the electromagnetic absorption equivalent area having this antenna linear antenna is patterned Y-shape, or
In addition, the ends of the linear antennas whose ends extending in three directions are adjacent
An electromagnetic shielding blind characterized by being arranged regularly so as to approach the central intersection . 2. The linear antenna is a composite antenna formed by combining the first antenna with a Y-shape and the second antenna with a Y-shape with an outline frame character surrounding the second antenna. The described electromagnetic shielding blind.