JP2931588B1 - Electromagnetic wave absorbing device and its structure, electromagnetic wave absorbing method, and method for adjusting electromagnetic wave absorbing frequency of electromagnetic wave absorbing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic wave absorbing device and a method which can reliably absorb electromagnetic waves radiated from a portable telephone set, etc. SOLUTION: An antenna conductor pattern 18 of an antenna for receiving an electromagnetic wave having a predetermined frequency is formed on a dielectric substrate 3, the pattern 18 is connected to a high frequency dielectric resonator 5 having a cylindrical dielectric member 5a sandwiched by a pair of electrodes 11 via a coupling capacitor 8, and the other electrode of the resonator 5 is grounded as connected to a grounding plate 2 through a high frequency diode 6. An electromagnetic wave radiated from a portable telephone set is received by the antenna, a signal indicative of the received wave is absorbed as attenuated by the resonator 5 through the capacitor 8, and then grounded to the grounding plate 2 through the diode 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave absorbing device for absorbing electromagnetic waves radiated from a portable telephone or the like, a structure thereof, an electromagnetic wave absorbing method, and a method for adjusting an electromagnetic wave absorbing frequency of the electromagnetic wave absorbing device.

[0002]

2. Description of the Related Art In recent years, the penetration rate of portable telephones in Japan and overseas has been remarkable, but in recent years, the influence of electromagnetic waves on the human body has become a social problem, and portable telephones that use an oscillating portion near the head have been used. Again, there is concern about the effects on the human body,
As a countermeasure for these, an electromagnetic wave shield, an electromagnetic wave absorber, an electromagnetic wave absorber, an electromagnetic wave neutralizer, and the like have been proposed and put to practical use.

For example, an electromagnetic wave shielding material (a chemically coated copper mesh material) is used to cut a predetermined size, and then cut into a handset portion of a mobile phone and used in an electromagnetic wave absorbing device or a breast pocket. What is called neutralization and detoxification of electromagnetic waves just by putting it, in a molded product containing tourmaline (tourmaline), in an environment where electromagnetic waves are emitted,
There are things that absorb electromagnetic energy and generate negative ions to make the human body healthy, but even if the claim that negative ions are good for the body is correct, the electromagnetic wave body will not be attenuated, so in terms of preventing electromagnetic waves It does not seem to solve the problem.

In addition, a ring that changes harmful electromagnetic waves into electromagnetic waves that are good for the body, such as a healthy magnetic ring, a high-wave ceramics, etc., which improve minus waves emitted from electrical appliances into positive waves, and harmful electromagnetic waves are affixed when attached to equipment. Films that sum up, special ceramics react to electromagnetic waves to change the fluctuating magnetic field into a static magnetic field that does not affect the human body, waves that oscillate from natural stones change bad electromagnetic waves that adversely affect the human body into good electromagnetic waves, Ceramics resonate with wavelengths to absorb electromagnetic waves, and tourmaline generates negative ions that are beneficial to the human body. Of these, none of them have been scientifically described.

Further, a mixture of magnetic powder and rubber or resin is formed into a ring shape and attached to the base of an antenna of a mobile phone to absorb unnecessary electromagnetic waves leaking from the mobile phone and minimize the adverse effect of microwaves on the human body. (For example, see Japanese Patent Application Laid-Open No. 8-250887).

[0006]

However, as described above, the mechanism of the electromagnetic wave shield, the electromagnetic wave absorbing device, and the electromagnetic wave neutralizer is unclear and the scientific explanation is not sufficiently provided, and there are many questions about the effect. .

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to surely absorb an electromagnetic wave radiated from, for example, a portable telephone, etc., an electromagnetic wave absorbing device, its structure, and an electromagnetic wave absorbing method as compared with the prior art. And a method for adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device.

[0008]

An electromagnetic wave absorbing device according to the present invention has a dielectric substrate on which an antenna conductor pattern of an antenna for receiving an electromagnetic wave of a predetermined frequency is formed, and one end connected to the antenna conductor pattern. A coupling capacitor and a cylindrical dielectric are sandwiched between a pair of electrodes,
A high-frequency dielectric resonator having one electrode connected to the other end of the coupling capacitor; a high-frequency diode having one end connected to the other electrode of the high-frequency dielectric resonator; and a high-frequency diode connected to the other end of the high-frequency diode With a ground plate,
An electromagnetic wave signal received by the antenna is absorbed and attenuated by the high-frequency dielectric resonator via the coupling capacitor, and then grounded to the ground plate via the high-frequency diode.

In the above electromagnetic wave absorbing device, preferably, the high frequency dielectric resonator is made of BaTiO ₃ + Nd ₂ O
₃ + TiO ₂ + Bi ₂ (TiO ₃ ) ₃ system, TiO ₂ + ZrO ₂
+ SnO ₂ system, BaTi ₄ O ₉ + SnO ₂ system, BaTi ₄ O ₉
It is characterized by being formed using any material such as + ZrO ₂ system.

[0010] In the electromagnetic wave absorbing device, preferably, the electromagnetic wave absorbing device further includes first and second cases each made of an electrically insulating material, and the high-frequency dielectric resonator has a cylindrical shape. The ground plate has a convex portion and a small hole for voice passage at the center thereof, and the dielectric substrate, the coupling capacitor, the high-frequency dielectric resonator, the high-frequency diode, and the ground plate are connected to the ground plate. The coupling capacitor and the high-frequency dielectric resonator are sandwiched between the first and second cases, are housed inside a convex portion of the ground plate, and the electromagnetic wave absorbing device is mounted on a receiver of a mobile phone, The portable telephone is characterized in that the outside of the convex portion of the ground plate is in contact with the ear of the operator of the mobile phone.

The structure of the electromagnetic wave absorbing device according to the present invention is the same as the structure of the electromagnetic wave absorbing device, wherein the electromagnetic wave absorbing device further includes first and second cases each made of an electrically insulating material, The body resonator has a cylindrical shape, the ground plate has a convex portion, and has a small hole for voice passage at the center thereof, and the dielectric substrate, the coupling capacitor, the high-frequency dielectric resonator, and the The high-frequency diode and the ground plate are sandwiched between the first and second cases, and the coupling capacitor and the high-frequency dielectric resonator are housed inside a convex portion of the ground plate. Is mounted on the receiver of the mobile phone, and has a structure in which the outside of the convex portion of the ground plate contacts the ear of the operator of the mobile phone.

According to the electromagnetic wave absorbing method of the present invention, an electromagnetic wave is received by an antenna having an antenna conductor pattern formed on a dielectric substrate, and the received electromagnetic wave signal is converted into a cylindrical shape through a coupling capacitor. Inputting and absorbing a high-frequency dielectric resonator having a shaped dielectric sandwiched between a pair of electrodes to bring the high-frequency dielectric resonator into a resonance state, and absorbing the high-frequency dielectric resonator by the high-frequency dielectric resonator Rectifying the electromagnetic wave signal by a high-frequency diode,
Grounding the rectified electromagnetic wave signal with a ground plate.

In the above electromagnetic wave absorbing method, preferably, the antenna receives an electromagnetic wave radiated by a portable telephone, and the high-frequency dielectric resonator absorbs the received electromagnetic wave signal. .

In the electromagnetic wave absorbing method, preferably, the high-frequency diode rectifies the absorbed electromagnetic wave signal, and the ground plate transmits the rectified electromagnetic wave signal to an ear of an operator of the portable telephone. It is characterized in that it is grounded to the ground via a part.

According to the method for adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device according to the present invention, in the electromagnetic wave absorbing device, one electrode of the high-frequency dielectric resonator has a C-shape having a slit, The method includes adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device by changing the interval between the slits.

The method for adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device according to the present invention is characterized in that in the electromagnetic wave absorbing device, a part of one electrode of the high-frequency dielectric resonator is scraped off. Adjusting the electromagnetic wave absorption frequency.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment according to the present invention will be described with reference to the drawings. In the following embodiments, embodiments relating to an electromagnetic wave absorbing device that absorbs an electromagnetic wave radiated from a mobile phone or the like, its structure, an electromagnetic wave absorbing method, and a method of adjusting the electromagnetic wave absorbing frequency of the electromagnetic wave absorbing device will be described. Of course, it protects only a portion where the electromagnetic wave existing in the fixed range antenna area enters from the ear of the receiver, and does not prevent the electromagnetic wave for a call.

FIG. 1 is a top view of an electromagnetic wave absorbing device 20 according to an embodiment of the present invention, and FIG.
It is a longitudinal cross-sectional view along the A 'line. As shown in the equivalent circuit of FIG. 5, the electromagnetic wave absorbing device 20 of the present embodiment includes a loop antenna 9 for receiving an electromagnetic wave, a coupling capacitor 8,
Low-loss high-frequency dielectric resonator 5 and high-frequency diode 6
And the earth plate 2 are connected in series.
As shown in FIG. 14, by being attached directly above the receiver 19 b of the mobile phone 19, electromagnetic waves radiated from the antenna 19 a of the mobile phone 19 and particularly radiated to the operator's head are absorbed and attenuated. It is characterized by:

1 and 2, reference numeral 1 denotes an upper resin case, and 4 denotes a lower resin case. These cases 1 and 4 are fixed by sandwiching an earth plate 2 and a dielectric substrate 3 therebetween. ing. A fixed mounting double-sided adhesive tape 15 is attached to the lower side of the lower surface resin case 4 in consideration of the mounting of the mobile phone 19 and the like. Here, a small hole for voice passage for receiving a voice is formed in the center of the ground plate 2. The ground plate 2 has a convex shape, and has a structure in which the outside of the convex portion comes into contact with the ear of the operator of the mobile phone 19, and the surface of the ground plate 2 is plated with gold or silver or the like. It has conductivity. Since the ground plate 2 has a convex shape, the high-frequency diode 6 is provided inside the convex portion.
And the low-loss high-frequency dielectric resonator 5 can be accommodated, and can be brought into contact with the ear portion of the operator with a larger area, thereby fitting the ear portion more naturally, The effect of the grounding described later can be increased. When the electromagnetic wave absorbing device 20 is attached to the mobile phone 19, the received voice output from the receiver 19 b is transmitted through the central hole 4 a of the lower surface resin case 4 and the voice passage small hole 16 of the ground plate 2 to the ear of the operator. Is configured to reach.

The dielectric substrate 3 is made of, for example, glass epoxy, and, as shown in FIG.
The antenna conductor pattern 18 of the loop antenna 9 having the wavelength is formed in a loop shape. 1 and 2, 5
Is a low-loss high-frequency dielectric resonator, 6 is a high-frequency diode,
7a and 7b are bonding solders, and 8 is a coupling capacitor.

FIG. 3 is a top view when the low-loss high-frequency dielectric resonator 5 is mounted on the dielectric substrate 3 in the electromagnetic wave absorbing device 20 of FIG. As shown in FIG. 3, on the pattern surface portion of the dielectric substrate 3, a resist 10 is printed in a ring shape on the entire surface or the outer peripheral portion thereof in contact with the ground plate 2 except for the dielectric bonding portion, and is cured. Electrical insulation from the plate 2 is performed.

FIG. 4 is a rear view of the electromagnetic wave absorbing device 20 of FIG. 1 when the low-loss high-frequency dielectric resonator 5 is mounted on the dielectric substrate 3. As shown in FIG. 4, a substantially rectangular receiving hole 3c for receiving the coupling capacitor 8 so as not to come into contact with the dielectric substrate 3 is provided near the center of the dielectric substrate 3. A low-loss high-frequency dielectric resonator 5 formed so as to penetrate in the vertical direction and having a coupling capacitor 8 mounted thereon is mounted on the dielectric substrate 3,
Here, the mounting surface side of the dielectric resonator 5 is joined to the surface of the dielectric substrate 3.

FIG. 9 is a side view showing a state in which the low-loss high-frequency dielectric resonator 5 is mounted on the dielectric substrate 3 in the electromagnetic wave absorbing device 20 of FIG. 1, and FIG. 10 is a partially enlarged longitudinal sectional view thereof. . 9 and 10, a low-loss high-frequency dielectric resonator 5 is bonded to a dielectric substrate 3 on which an antenna conductor pattern of a loop antenna 9 is formed by using a conductive adhesive 17. The low-loss high-frequency dielectric resonator 5 has a cylindrical shape, and is formed by sandwiching a cylindrical dielectric 5a made of, for example, ceramics between the coupling capacitor-side electrode 11 and the high-frequency diode-side electrode 13. The dielectric resonator 5 constitutes, for example, an LCR parallel resonator circuit. Here, the coupling capacitor side electrode 1
1 is thermosetting-bonded to an antenna conductor pattern 18 formed on the dielectric substrate 3 using a conductive adhesive 17 which is cured by heat. On the other hand, the ground plate 2 is bonded onto the dielectric substrate 3 using an epoxy adhesive 14.

FIG. 6 is a perspective view of the electromagnetic wave absorbing device 20 of FIG. 1 viewed from the surface of the coupling capacitor side electrode 11 of the low-loss high-frequency dielectric resonator 5. In FIG. 6, in a capacitor-side electrode 11 having a C-shape, a slit 12 is formed in a part of the capacitor-side electrode 11 to form an unclosed C-shape, and a chip-shaped thin film is formed on the slit 12. Alternatively, a coupling capacitor 8 composed of a multilayer capacitor is attached.

FIG. 7 is a perspective view of the electromagnetic wave absorbing device 20 of FIG. 1 as viewed from the surface of the high-frequency diode-side electrode 13 of the low-loss high-frequency dielectric resonator 5. Diode side electrode 1
3 is formed in a ring shape. Electrodes 11 and 13 on both sides
Both are silver electrodes, and are formed by printing and firing to a thickness of 3 to 5 μmm.

FIG. 8 is a perspective view when the coupling capacitor 8 is attached to the low-loss high-frequency dielectric resonator 5 in the electromagnetic wave absorbing device 20 of FIG. In the present embodiment, electrodes are formed on the upper and lower surfaces of the coupling capacitor 8, and as shown in FIG. 8, one of the electrodes is provided at both ends 11 a and 11 b of the C-shaped electrode 11 in which the slit 12 is formed. The other electrode is electrically connected to one end of the high-frequency diode 6 while being straddled and in contact with and electrically connected thereto.

In this embodiment, the coupling capacitor 8 is connected, but instead of this, the resonance frequency may be changed by adjusting the coupling capacitance with the loop antenna 9 by changing the interval between the slits 12. . According to the experiment of the inventor, when the interval between the slits 12 was changed from 0.1 mm to 0.5 mm, the resonance frequency could be changed by about 300 MHz. Further, instead of changing the resonance frequency by changing the interval between the slits 12, a part of the high-frequency capacitor side electrode 11 is cut off, that is,
The resonance frequency may be changed mainly by reducing the inductance component included in the electrode 11 of the dielectric resonator 5.

Further, for example, by changing the material of the low-loss high-frequency dielectric resonator 5 or changing its size to increase the resistance component, the Q of the low-loss high-frequency dielectric resonator 5 is reduced. Thereby, the resonance characteristics of the resonance circuit including the low-loss high-frequency dielectric resonator 5 may be broadened. As a result, electromagnetic wave energy in a wider band can be absorbed and attenuated. Further, by widening the band, even if the resonance setting frequency of the resonance circuit deviates from the target frequency to be absorbed, the electromagnetic wave energy can be substantially absorbed.

FIG. 5 is a circuit diagram showing an equivalent circuit according to the basic structure of the electromagnetic wave absorbing device 20 of FIG. As shown in FIG. 5, a coupling capacitor 8, a low-loss high-frequency dielectric resonator 5, and a high-frequency diode 6 are connected in series, and a loop antenna 9 that receives an electromagnetic wave radiated from a mobile phone 19 is coupled. Grounding capacitor 2 via a capacitor 8, a low-loss high-frequency dielectric resonator 5, and a high-frequency diode 6.
And electrically grounded. Here, the high-frequency diode 6 is formed of, for example, a GaAs diode, a Schottky diode, or the like, and is formed by, for example, connecting two diodes having opposite conduction directions in parallel. Further, the high-frequency diode 6 may have a configuration of half-wave rectification or full-wave rectification.

The electromagnetic wave absorbing device 2 configured as described above
At 0, since the electromagnetic wave absorbing device 20 is attached only to the receiver 19b, among the electromagnetic waves radiated from the antenna 19a of the mobile phone 19, the electromagnetic wave leaking to the ear portion of the operator is particularly a loop antenna. After being received by 9, the signal of the electromagnetic wave is input to the low-loss high-frequency dielectric resonator 5 via the coupling capacitor 8. The low-loss high-frequency dielectric resonator 5 absorbs and accumulates the energy of the electromagnetic wave signal to be in a resonance state, and the absorbed electromagnetic wave signal current is rectified by the high-frequency diode 6 to be converted to direct current, and ground as a minute current. Grounded via plate 2. Here, the ground plate 2 is in contact with the ear of the operator, and the minute current flows from the ground plate 2 to the ground via the operator and is grounded. More preferably, the ground plate 2 may be connected to, for example, a car body to be grounded. Here, the low-loss high-frequency dielectric resonator 5 and the high-frequency diode 6 include a resistance component, and a part of the electromagnetic wave energy is converted into heat energy and consumed by the resistance component. Becomes a very small current. According to this method, not only the loop antenna 9 but also the electromagnetic wave directly received by the low-loss high-frequency dielectric resonator 5 can be absorbed, attenuated, and eliminated.

FIG. 14 is a perspective view when the electromagnetic wave absorbing device 20 of FIG. FIG.
As shown in FIG.
Is attached directly above the receiver 19b by using, for example, a double-sided adhesive tape 15 (see FIG. 2).

FIG. 15 is a side view showing the electric field strength and the magnetic field strength when the electromagnetic wave absorbing device 20 of FIG. 1 is not attached to the portable telephone 19 and when it is attached. In other words, FIG. 15 shows the measured attenuation of the electromagnetic solution strength before and after the electromagnetic wave absorbing device 20 is attached.
It can be seen that the electromagnetic waves near zero are significantly absorbed, attenuated, and extinguished. Therefore, of the electromagnetic waves radiated from the mobile phone 19, the electromagnetic waves that enter the operator's head through the ears of the operator in close proximity to the receiver 19b of the mobile phone 10 can be absorbed, attenuated, and eliminated. Therefore, the protection effect of protecting the operator's head from electromagnetic waves is extremely large.

As shown in FIG. 1, FIG. 2, FIG. 14, and FIG. 15, since the purpose is to absorb electromagnetic waves that enter the brain through the ears of the operator, the conductor pattern 18 of the loop antenna 9 is Since the light is absorbed and attenuated within the range, the call function by communication between the mobile phone 19 and the base station is not impaired.

In this embodiment, the loop antenna 9
However, the present invention is not limited to this, and may be a single type antenna such as a dipole antenna or a whip antenna. Dielectric 5a of low-loss high-frequency dielectric resonator 5
Is preferably a high-frequency, low-loss material. As the material, TiO ₂ + ZrO ₂ + SnO ₂ or BaTi ₄ O ₉ +
SnO ₂ system, BaTi ₄ O ₉ + ZrO ₂ system, BaTiO ₃ +
Any of Nd ₂ O ₃ + TiO ₂ + Bi ₂ (TiO ₃ ) ₃ based materials may be used. It is appropriate that the permittivity ε is about 40 to 90 from the relationship of the shape and dimensions. Further, since the low-loss high-frequency dielectric resonator 5 is attached to the receiver, it is desirable that the low-loss dielectric resonator 5 has a cylindrical shape so as not to disturb a call.

In the above embodiment, the upper resin case 1 and the lower resin case 4 are used. However, the material of these cases 1 and 4 is not limited to resin, but may be formed of other electric insulating materials. You may.

[0036]

EXAMPLE An example of the electromagnetic wave absorbing device 20 of the present embodiment will be described below. The dielectric material 5a of the low-loss high-frequency dielectric resonator 5 uses a TiO ₂ + ZrO ₂ + SnO ₂ system, and uses a material having a dielectric constant ε = 40, low loss, and excellent τ _f characteristics (temperature coefficient characteristics of resonance frequency). Was. The dielectric 5a
Due to shape restrictions, outer shape 11.6mm, inner diameter 7.0mm,
Molded with a thickness of 3.3mm, molding pressure 4400Kg / c
m ² , sintering temperature was 1320 ° C., and sintering was performed at a peak temperature of 2 hours. The dimensions after firing are 10.2mm in outer diameter and 6.0m in inner diameter.
m and a thickness of 2.8 mm. The electrodes 11, 1
A silver electrode 3 was printed on both sides and fired at 850 ° C. to obtain a low-loss high-frequency dielectric resonator 5. A high-frequency resonance circuit was formed by attaching a thin-film chip capacitor or a high-frequency multilayer chip capacitor serving as the coupling capacitor 8 thereto.

The shown resonance characteristics of the high frequency resonant circuit (reflection coefficient S ₂₂ parameter characteristic) in FIGS. Here, FIG. 11 and FIG. 12, which is an enlarged spectrum diagram, are the results of another experiment. As is apparent from FIGS. 11 and 12, the attenuation amount is maximum at around 1.5 GHz and around 1.4 GHz, respectively. And can absorb electromagnetic waves.

FIG. 13 shows the relationship between the resonance frequency of the high-frequency resonance circuit and the capacitance value of the coupling capacitor 8. FIG.
As shown in FIG. 5, it can be understood that the resonance frequency, that is, the frequency of the electromagnetic wave to be absorbed can be increased by reducing the capacitance value of the coupling capacitor 8. Therefore, the target resonance frequency is set by adjusting the capacitance value of the coupling capacitor 8 so that the resonance frequency matches the transmission frequency of the mobile phone 19, for example. Further, the low-loss high-frequency dielectric resonator 5 has a predetermined bandwidth, and resonates even if it slightly deviates from the center frequency.

As described above, according to the embodiment of the present invention, since the electromagnetic wave absorbing device 20 is mounted on the receiver 19b, the electromagnetic wave energy collected by the loop antenna 9 is low-loss high-frequency dielectric material. The energy is accumulated in the body resonator 5 to be in a resonance state, and then the electromagnetic wave energy is rectified by the high-frequency diode 6 and then grounded via the earth plate 2 as a minute current. Therefore, the electromagnetic wave energy around the loop antenna 9 can be absorbed, attenuated, and eliminated, and the operator's head can be protected from the electromagnetic wave. Here, in particular, it is possible to attenuate, eliminate, and block electromagnetic waves from the handset through the ear to the operator's brain, thereby reducing the effect on the human body. In addition, since only the electromagnetic wave near the loop antenna 9 is absorbed, only the receiver 19b provided with the loop antenna 9 is protected and absorbed, attenuated, and eliminated without affecting the electromagnetic wave for communication. Therefore, no call interruption occurs.

Further, the capacitance value of the coupling capacitor 8 is changed, or the interval between the slits 12 of the electrode 11 is changed,
Alternatively, by removing a part of the electrode 11, the resonance frequency of the resonance circuit including the low-loss high-frequency dielectric resonator 5 and the coupling capacitor 8 can be easily changed. The absorption frequency (corresponding to the above resonance frequency) can be changed. Thereby, the frequency of the electromagnetic wave to be absorbed can be easily changed.
To a target electromagnetic wave frequency such as the transmission frequency of the target. Also, by lowering the Q of the low-loss high-frequency dielectric resonator 5 to broaden the resonance characteristics, it is possible to absorb, attenuate, and extinguish a wide range of electromagnetic wave energy.

Further, the structure of the electromagnetic wave absorbing device 20 is simple, small and lightweight, and the portable telephone 1
9 and so on.

[0042]

As described above in detail, according to the electromagnetic wave absorbing device and method according to the present invention, the dielectric substrate on which the antenna conductor pattern of the antenna for receiving the electromagnetic wave of the predetermined frequency is formed, A high-frequency dielectric resonator having a coupling capacitor connected to the antenna conductor pattern and a cylindrical dielectric sandwiched between a pair of electrodes, one of which is connected to the other end of the coupling capacitor; A high-frequency diode having one end connected to the other electrode of the high-frequency dielectric resonator, and a ground plate connected to the other end of the high-frequency diode, for coupling the electromagnetic wave signal received by the antenna for the coupling. After being absorbed and attenuated by the high-frequency dielectric resonator via a capacitor, it is grounded to the earth plate via the high-frequency diode.

Therefore, according to the present invention, of the electromagnetic waves emitted from, for example, a portable telephone, the electromagnetic wave energy around the antenna can be absorbed, attenuated, and eliminated.
The operator's head can be protected from electromagnetic waves. Here, in particular, it is possible to attenuate, eliminate, and block electromagnetic waves from the handset through the ear to the operator's brain, thereby reducing the effect on the human body. In addition, since it absorbs only the electromagnetic waves near the antenna, it does not affect the electromagnetic waves for calls and protects only the receiver with the antenna, and absorbs, attenuates, and disappears. Absent.

Further, the capacitance value of the coupling capacitor is changed, or the interval between the slits of the electrode of the high-frequency dielectric resonator is changed, or a part of the electrode is cut off, so that the high-frequency dielectric resonator is removed. Since the resonance frequency of the resonance circuit including the capacitor and the coupling capacitor can be easily changed, the electromagnetic wave absorption frequency can be changed by the electromagnetic wave absorbing device.
As a result, the frequency of the electromagnetic wave to be absorbed can be easily changed, and for example, the target electromagnetic wave frequency such as the transmission frequency of the mobile phone can be set.

Further, the structure of the electromagnetic wave absorbing device is simple, small and lightweight, and can be easily attached to a portable telephone or the like.

[Brief description of the drawings]

FIG. 1 is a top view of an electromagnetic wave absorbing device 20 according to one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view taken along line A-A 'of FIG.

FIG. 3 is a top view when the low-loss high-frequency dielectric resonator 5 is attached to the dielectric substrate 3 in the electromagnetic wave absorbing device 20 of FIG.

4 is a rear view of the electromagnetic wave absorbing device 20 of FIG. 1 when a low-loss high-frequency dielectric resonator 5 is mounted on a dielectric substrate 3. FIG.

FIG. 5 is a circuit diagram showing an equivalent circuit according to a basic structure of the electromagnetic wave absorbing device 20 of FIG.

6 is a perspective view of the electromagnetic wave absorbing device 20 of FIG. 1 as viewed from the surface of the coupling capacitor-side electrode 11 of the low-loss high-frequency dielectric resonator 5. FIG.

7 is a perspective view of the electromagnetic wave absorbing device 20 of FIG. 1 as viewed from the surface of the high-frequency diode-side electrode 13 of the low-loss high-frequency dielectric resonator 5. FIG.

8 is a perspective view when the coupling capacitor 8 is attached to the low-loss high-frequency dielectric resonator 5 in the electromagnetic wave absorbing device 20 of FIG.

9 is a side view showing a state in which the low-loss high-frequency dielectric resonator 5 is attached to the dielectric substrate 3 in the electromagnetic wave absorbing device 20 of FIG.

10 is a partially enlarged longitudinal sectional view showing a state in which the low-loss high-frequency dielectric resonator 5 is attached to the dielectric substrate 3 in the electromagnetic wave absorbing device 20 of FIG.

11 is a spectrum diagram showing resonance characteristics of a high-frequency resonance circuit in which a coupling capacitor 8 is connected to a low-loss high-frequency dielectric resonator 5 used in the electromagnetic wave absorbing device 20 of FIG.

FIG. 12 is an enlarged spectrum diagram of a resonance characteristic different from the resonance characteristic of FIG.

13 is a graph showing the relationship between the resonance frequency of the high-frequency resonance circuit of FIG. 11 and the capacitance value of the coupling capacitor 8. FIG.

FIG. 14 shows the electromagnetic wave absorbing device 20 of FIG.
FIG. 9 is a perspective view when attached to No. 9.

FIG. 15 shows a mobile phone 1 using the electromagnetic wave absorbing device 20 of FIG.
9 is a side view showing electric field strength and magnetic field strength when not attached to 9 and when attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Upper surface resin case, 2 ... Ground plate, 3 ... Dielectric substrate, 4 ... Lower surface resin case, 5 ... Low loss high frequency dielectric resonator, 5a ... Dielectric, 6 ... High frequency diode, 7a, 7b ... Solder, 8 ... Coupling capacitor, 9 ... Antenna, 10 ... Resist, 11 ... Coupling capacitor side electrode, 12 ... Slit, 13 ... High frequency diode side electrode, 14 ... Epoxy resin adhesive, 15 ... Double-sided adhesive tape, 16 ... Sound passage Small hole, 17: conductive adhesive, 18: antenna conductor pattern, 19: mobile phone, 19a: antenna, 19b: receiver, 20: electromagnetic wave absorbing device

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H05K 9/00 H01Q 17/00

Claims (9)

(57) [Claims] 1. A pair of a dielectric substrate on which an antenna conductor pattern of an antenna for receiving an electromagnetic wave of a predetermined frequency is formed, a coupling capacitor having one end connected to the antenna conductor pattern, and a cylindrical dielectric. A high-frequency dielectric resonator having one electrode connected to the other end of the coupling capacitor; and a high-frequency diode having one end connected to the other electrode of the high-frequency dielectric resonator. An earth plate connected to the other end of the high-frequency diode, and after absorbing and attenuating the electromagnetic wave signal received by the antenna by the high-frequency dielectric resonator via the coupling capacitor, An electromagnetic wave absorbing device, which is grounded to the ground plate via a high-frequency diode. 2. The electromagnetic wave absorbing device according to claim 1, wherein said high-frequency dielectric resonator is made of BaTiO ₃ + Nd ₂ O ₃ +
TiO ₂ + Bi ₂ (TiO ₃ ) ₃ system, TiO ₂ + ZrO ₂ + S
nO ₂ system, BaTi ₄ O ₉ + SnO ₂ system, BaTi ₄ O ₉ + Z
An electromagnetic wave absorber formed by using any material such as rO ₂ . 3. The electromagnetic wave absorbing device according to claim 1, wherein the electromagnetic wave absorbing device further includes first and second cases each made of an electrically insulating material, and the high-frequency dielectric resonator is a cylinder. The earth plate has a convex portion and a small hole for voice passage at the center thereof, and the dielectric substrate, the coupling capacitor, the high-frequency dielectric resonator, the high-frequency diode, and the ground. The board is
The coupling capacitor and the high-frequency dielectric resonator are sandwiched between the first and second cases, are housed inside a convex portion of the ground plate, and the electromagnetic wave absorbing device is attached to a receiver of a mobile phone. An electromagnetic wave absorbing device, wherein an outer side of the convex portion of the ground plate is configured to contact an ear of an operator of the mobile phone. 4. The structure of the electromagnetic wave absorbing device according to claim 1, wherein the electromagnetic wave absorbing device further includes first and second cases, each of which is made of an electrically insulating material. Has a cylindrical shape, the grounding plate has a convex portion and has a small hole for voice passage at the center thereof, and the dielectric substrate, the coupling capacitor, the high-frequency dielectric resonator, and the high-frequency diode The ground plate is
The coupling capacitor and the high-frequency dielectric resonator are sandwiched between the first and second cases, are housed inside a convex portion of the ground plate, and the electromagnetic wave absorbing device is attached to a receiver of a mobile phone. A structure of the electromagnetic wave absorbing device, characterized in that the structure has a structure in which the outside of the convex portion of the ground plate contacts the ear of the operator of the mobile phone. 5. An electromagnetic wave is received by an antenna of an antenna conductor pattern formed on a dielectric substrate, and a signal of the received electromagnetic wave is coupled to a pair of cylindrical dielectrics via a coupling capacitor. Inputting and absorbing the high-frequency dielectric resonator sandwiched between the electrodes to bring the high-frequency dielectric resonator into a resonance state; and transmitting a signal of the electromagnetic wave absorbed by the high-frequency dielectric resonator to a high-frequency diode. And rectifying the rectified electromagnetic wave signal with a ground plate. 6. The electromagnetic wave absorbing method according to claim 5, wherein the antenna receives an electromagnetic wave radiated by a mobile phone, and the high-frequency dielectric resonator absorbs the received electromagnetic wave signal. Characteristic electromagnetic wave absorption method. 7. The electromagnetic wave absorbing method according to claim 6, wherein the high-frequency diode rectifies the signal of the absorbed electromagnetic wave, and the ground plate converts the signal of the rectified electromagnetic wave into an operation of the mobile phone. A method for absorbing electromagnetic waves, comprising: grounding to the ground via a user's ear. 8. The method for adjusting an electromagnetic wave absorption frequency of an electromagnetic wave absorbing device according to claim 1, wherein one of the electrodes of the high-frequency dielectric resonator has a slit having a slit. And adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device by changing the interval of the slits. 9. The method for adjusting an electromagnetic wave absorption frequency of an electromagnetic wave absorbing device according to claim 1, wherein a part of one electrode of the high-frequency dielectric resonator is cut off. Adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device, the method comprising adjusting the electromagnetic wave absorption frequency of the electromagnetic wave absorbing device.