JPH10169336A - Electro-magnetic shield blind - Google Patents

Abstract

PROBLEM TO BE SOLVED: To selecting only radio waves of a necessary frequency to shield other radio waves, by arranging periodically linear antennas patternized on light-shield plates or light-shielding films constituting a blind, taking a magnetic field absorption-equivalent area which the antennas have, into consideration. SOLUTION: Y-shaped small linear antennas 5 as a circuit pattern are periodically arranged on slat 1 faces as light-shielding plates, taking a magnetic field absorption-equivalent area which the antennas have. As a method to arrange patternized small linear antennas on synthetic resin slats 1, a silk printing, a pattern pressure adhesion, etc., are used for instance. When a conductor piece is existing in the air, if this face receives incident radio waves, a part thereof passes through the face and other radio waves are reflected. The attenuating characteristic of the transmissible waves depends on the shape of the conductor piece. When the conductor piece is a dipole shape, the received electric power is partly radiated again and a quarter of the power is absorbed into the linear antenna conductor as a heat loss.

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 necessity of electromagnetic shielding of buildings is indispensable when personal wireless devices to which radio technology is applied in buildings are used indoors within the legally required framework, and information security is also required. Therefore, it is necessary to block radio waves of the frequency, that is, to prevent both radiation and intrusion.

Conventionally, as an electromagnetic shield of a building structure, each floor surface can be sufficiently shielded by an iron plate or the like, and the outer wall surface and partitions between tenants can be effectively used in the microwave band by adding a metal foil or a metal mesh. Electromagnetic shielding can be performed.

On the other hand, when an opening such as a window is provided,
It is difficult to ensure electromagnetic shielding performance, and glass windows are provided with an electromagnetic shielding function by using glass with mesh or a glass to which a conductive film is attached. As an example, if a very thin vapor-deposited film of tungsten, aluminum, etc. is laminated over the entire surface or inside of the glass, visible light will be reduced by only 30-35%, but practically used digital cordless phones ( 1.
It is known that attenuation can be up to 20 to 30 dB for 9 GHz) or wireless LAN (2.45 GHz).

[0005]

However, in this method, it is possible to some extent to block invasive radio waves from the outside without impairing the sense of openness of a building with daylighting, but it is effective when windows are opened. In addition, there is no frequency selectivity, and radio waves other than the target frequency are blocked.

[0006] As a result, along with blocking outgoing radio waves from outside, radio waves of important public information such as broadcast waves of pagers, mobile phones, FMs, radios and the like used inside and outside the building are also blocked. And it causes a reflection obstacle of TV radio waves. Further, in practical use, electrical contact must be maintained without any gap including the window frame.

On the other hand, in Japanese Patent Application Laid-Open No. 2-16283,
Pleated electromagnetic shielding blinds with metal foil or conductive film attached to form an electromagnetic shielding layer have also been proposed, but this also has no frequency selectivity and blocks radio waves other than the target frequency. This is similar to the case of the window glass. In addition, in practical use, the blade is continuous although it is folded, and it is also necessary to maintain electrical contact without any gap including the frame, as in the case of the window glass, along the vertical frame guide liner. The balance member of the blade is moved up and down while always in contact with the guide piece.

An object of the present invention is to eliminate the disadvantages of the prior art, to enable electromagnetic shielding by selecting only radio waves of a required frequency, and to affect the continuity between members and the shielding performance of the connecting portion. Another object of the present invention is to provide an electromagnetic shielding blind that can be freely set because it does not require consideration of a grounding measure and that is excellent in convenience.

[0009]

In order to achieve the above object, the present invention firstly provides a light-shielding plate or a light-shielding film constituting a blind, in which a patterned linear antenna is provided. Secondly, the gist is that the linear antenna is Y-shaped.

Third, the linear antenna is composed of a plurality of types so as to block a plurality of frequencies. Fourth, the linear antenna can block two frequency bands of 1885 to 1950 MHz and 2420 to 2480 MHz. Fifth,
In the linear antenna, the first antenna has a Y-shape,
The gist of the present invention is to provide a composite antenna by combining the second antenna with a white frame character surrounding 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 reflection effect. In addition, due to absorption loss, the absorbed electromagnetic field is absorbed as heat loss due to propagation in the linear antenna. For this reason, if this film is attached to a plate such as a wall plate, glass, a ceiling plate, etc., electromagnetic shielding can be easily performed. The function is obtained.

Further, since the shield effect is provided by the reflection loss and the absorption loss by the linear antenna, it is not necessary to conduct the antenna to a metal sash such as a window frame, and the antenna can be freely set without being limited to the conductive connection. it can. In particular, since the film can be attached to the existing glass or the like, the electromagnetic shielding function can be easily added to the existing glass or the like without replacing it.

According to the second aspect of the present invention, the actual radio wave has various inclinations, not a horizontal line, but the linear antenna has a Y-shape, so that the inclination other than the horizontal radio wave can be reduced. It can respond to different radio waves.

According to the third aspect of the present invention, the patterned linear antenna can cut off a plurality of specific frequencies,
It can be more effective.

According to the fourth aspect of the present invention, there is further provided:
1885-1950MHz and 2420-2480MH
Specified to the two frequency bands of z, the digital cordless phone such as PHS and its data terminal and the wireless LAN are cut off by quasi-microwave, and other radio waves such as pager, mobile phone, FM, radio It does not attenuate radio wave services such as broadcast waves.

According to the fifth aspect of the present invention, a plurality of specific frequencies can be obtained by forming a composite antenna by combining a Y-shaped antenna and a Y-shaped white frame character surrounding the Y-shaped antenna. Objects that can be blocked can be arranged on the same plane.

[0017]

Embodiments of the present invention will be described below 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 type 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 a slat 1 as a light shielding plate constituting a blind in consideration of an electromagnetic field absorption equivalent area of the antenna. And arranged regularly.

The slat 1 is made of vinyl chloride, polyethylene,
Although a method using a synthetic resin plate such as polypropylene is used, a method of periodically arranging the patterned small linear antennas 5 on the slats 1 includes silk printing,
A method such as pattern crimping and the attachment by a film are conceivable.

This film is adhered to a synthetic resin film such as a polyimide film, a polyester film, or a polyethylene film, which is provided by an etching method, a laminating method, or a screen printing method using the linear antenna 5 as a line pattern. Is also possible.

The above-mentioned etching method is the same as a general printed circuit board in which a film as a flexible board and a copper foil attached thereto are used as a base material, a pattern portion is masked, and the remaining portion is dissolved with a solvent. . On the other hand, the screen printing method forms a line pattern 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 a coating may be applied thereon.

First, the basic principle related to the present invention will be described. As shown in FIG. 4, when the conductor piece 3 is in the air, when a radio wave is incident on this surface, one part passes and the other part is reflected. In this case, the attenuation 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) which is linear, a part of the absorbed (received power) is re-emitted, and 1/4 of the power is reduced to a linear antenna (conductor).
Is absorbed as heat loss.

As shown in FIG. 6, a half-wavelength (1/2) linear antenna placed parallel to a 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. Absorbs the electromagnetic field. Although the spread is not uniform, the calculated value of the equivalent area Ae is expressed by the following equation 1.

[0026]

[Equation 1] Ae ≒ 0.13λ ²

By arranging such linear antennas 4 on the slats 1 according to the equivalent area Ae as shown in FIG. 7, the same effect as when a metal film is attached can be obtained.

By the way, 1885 to 1950 MHz is the current personal communication (PHS-JAPAN., PCS-US. DECT-Europe) and FPLMTS (Future Public Land) which will be put into practical use from the year 2000.
Mobile Telephone System), 2420
Up to 2480 MHz is the ISM (Industrial-Sci
entific-Medical --- Industrial, scientific, medical) frequencies are allocated to wireless LANs in buildings, and are also used in microwave ovens and high-power linear accelerators for nondestructive testing.

In the case of PHS, the wavelength is λ = 153 mm,
For AN lambda = 122 mm Therefore, each of the linear antenna 4 area ^{Ae = 3043mm 2 atPHS, Ae =} 1935mm 2 at
This is equivalent to a LAN, which may be scattered on the slat 1 in consideration of the electromagnetic field absorption equivalent area Ae.

However, in the case where the linear antennas 4 are arranged in a horizontal line as shown in FIG. 7, it is impossible to cope with the fact that the actual wavefront of the radio wave has various inclinations instead of the horizontal line. Therefore, in this embodiment, the linear antennas 5 are Y-shaped as shown in FIG. 3, and are arranged such that the ends extending in three directions approach the center intersection of the adjacent linear antennas 5.

The reason why the shape is Y-shaped in this way is to cope with the polarization plane of the radio wave.
Regardless of the inclination of the wave surface of the radio wave, it resonates with either of them, so that it is possible to cope with radio waves having different inclinations other than the radio wave on the horizontal plane.

Further, when the blind is closed, the slats 1 are vertically oriented, and the upper and lower slats 1 have overlapping ends, so that an electromagnetic shielding effect as a large surface with no gap can be obtained. Further, the Y-shaped linear antenna 5 is a gathering surface of the plurality of slats 1 when such a blind is closed,
What is necessary is just to form the pattern which becomes a continuous arrangement | sequence.

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

As another embodiment, as shown in FIG.
A Y-shaped first linear antenna 5a of λ / (4 辺 ε) of 2450 MHz on one side and a thin copper wire (0.2φ) of λ / √ε of 1950 MHz surrounding the ring as a white frame character surrounding the ring. A composite linear antenna 5 may be formed in combination with the Y-shaped second linear antenna 5b. The reason why the shape is Y-shaped is to cope with the polarization plane of the radio wave, and the first linear antenna 5a and the second linear antenna 5b are used.
Is combined 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 intersect directly as shown in FIG. 8, but a non-conductive layer such as a non-conductive film is required. If they are interposed, they can be arranged so as to be overlapped vertically.

FIG. 9 shows a second embodiment of the present invention, in which the blind is a roll blind.

As is well known, the roll blind is of a shutter type in which a sheet 8 as a light-shielding film can be pulled out from a housing start-up section 6 having a mounting substrate 7 formed on the upper surface. Small Y-shaped linear antennas 5 as a pattern were regularly arranged in consideration of the electromagnetic field absorption equivalent area of the antenna.

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

Although not shown in the drawings as other embodiments, the linear antennas 5 are arranged on the vertical slats by using vertical blinds in which vertical slats are arranged horizontally, and Japanese Patent Application Laid-Open No. 2-16283. There is a case in which a linear antenna 5 is arranged on a blade with a pleated blind formed by folding such a blade.

[0040]

As described above, the electromagnetic shielding blind according to the present invention is capable of performing electromagnetic shielding by selecting only radio waves of a required frequency and exerting an electromagnetic shielding effect. Since there is no need to consider the effect on the shielding performance of the connection part and the grounding countermeasure, it is possible to set freely and the convenience is excellent.

[Brief description of the drawings]

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

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

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

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

FIG. 5 is a graph showing an example of a frequency response in the case of FIG. 4;

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

FIG. 7 is a partial plan view of a slat on 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 in the case of a roll 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 on the front page (72) Inventor Yoshimasa Yoshida 1-3-15 Awaza, Nishi-ku, Osaka-shi, Osaka Kashima Construction Co., Ltd.Kansai Branch (72) Inventor Kazushi Yamanoue 1-3-15 Awaza, Nishi-ku, Osaka-shi, Osaka Kashima Inside the Kansai Branch of Construction Co., Ltd. No. 1 Kashima Construction Co., Ltd.

Claims (5)

[Claims] An electromagnetic shielding blind characterized in that patterned linear antennas are periodically arranged on a light shielding plate or a light shielding film constituting a blind in consideration of an electromagnetic field absorption equivalent area of the antenna. . 2. The electromagnetic shielding blind according to claim 1, wherein the linear antenna is Y-shaped. 3. The electromagnetic shielding blind according to claim 1, wherein the linear antenna comprises a plurality of types so as to block a plurality of frequencies. 4. The electromagnetic shielding blind according to claim 1, wherein the linear antenna can cut off two frequency bands of 1885 to 1950 MHz and 2420 to 2480 MHz. 5. The linear antenna according to claim 1, wherein the first antenna is a Y-shaped antenna, and the second antenna is a composite antenna formed by combining the first antenna with a Y-shaped outline character surrounding the second antenna. An electromagnetic shielding blind according to claim 4.