JPH11298216A - Dielectric resonator - Google Patents

Abstract

(57) [Problem] To provide a dielectric resonator capable of adjusting a resonance frequency without changing at least one of a shape, a size, and a constituent material. A base 10 made of a dielectric variable material is provided.
In addition, an outer conductor 13, an inner conductor 12, and a short-circuit conductor 19 are provided.
4, 17 are provided in a non-contact manner,
A bias voltage is applied to the base 17 by the control voltage generating means 18, and an electric field is applied to a portion between the electrodes 15 and 17 of the base 10, thereby changing the dielectric constant of the base 10 and changing the resonance frequency and the like. Let it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric resonator used for a communication device, a voltage control circuit and the like.

[0002]

2. Description of the Related Art FIGS. 17 and 18 are a perspective view and a sectional view showing a conventional dielectric resonator.

In FIGS. 17 and 18, reference numeral 1 denotes a base made of a dielectric material, and the base 1 has a cylindrical structure.
A through hole 2 is provided. Reference numeral 3 denotes an outer conductor provided on the outer surface of the base 1, 4 denotes an inner conductor formed on the inner surface formed by the through hole 2, and 5 denotes a connecting conductor connecting the outer conductor 3 and the inner conductor 4.

[0004] The dielectric resonator constructed as described above has a unique resonance characteristic by changing the dielectric constant of the base 1 and the like, and changing the shapes and constituent materials of the outer conductor 3 and the inner conductor 4. After obtaining the frequency, this dielectric resonator is used as one component of a filter circuit such as a communication device.

[0005]

However, in the above-described structure, when dielectric resonators having various resonance frequencies are to be formed, as described above, the dielectric material forming the base 1 is not used. It is necessary to change the permittivity, the shape of the outer conductor 3 and the inner conductor, and the constituent materials, so that a number of dielectric resonators must be designed depending on the resonance frequency. Was.

An object of the present invention is to provide a dielectric resonator capable of adjusting a resonance frequency without changing at least one of a shape, a size, and a constituent material. Aim.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a conductive layer formed on a base made of a variable dielectric constant material, and the dielectric constant of the base is increased by applying an external action to the base. Means for changing the dielectric constant.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 provides a base made of a variable dielectric constant material, a conductor layer formed on the base, and an external action applied to the base. A variable dielectric constant means for changing the dielectric constant of the base, and changing the dielectric constant of the base by the dielectric constant variable means to change the resonance frequency and the like of the dielectric resonator. Therefore, it is possible to cover a certain level of resonance frequency without changing the shape, material, and the like, so that it is possible to share parts and improve productivity.

According to a second aspect of the present invention, in the first aspect, a material having a dielectric constant changed by applying an electric field is used as the variable dielectric constant material, a through hole is provided in the base, and a conductive layer is formed on the base. An outer conductor provided on an outer side surface, an inner conductor provided on an inner side surface of the base, and a connecting conductor connecting the outer conductor and the inner conductor, wherein the inner conductor, the outer conductor, and the short-circuit conductor By providing an electrode provided in a non-contact manner, using a control voltage generating means as a dielectric constant varying means, and applying an electric field to the base through the control voltage generating means using the electrode, an electric field is applied to the base. , The dielectric constant of the base can be changed, so that power consumption is extremely small and power can be saved.

According to a third aspect of the present invention, in the second aspect, the first electrode provided on the outer surface of the base in non-contact with the outer conductor, and the first electrode on the inner surface of the base in non-contact with the inner conductor. A second electrode provided, wherein a bias voltage is applied between the first electrode and the second electrode by a control voltage generating means, and an electric field is applied to the base, so that the distance between the electrodes is increased. Can be narrowed, a sufficiently large electric field can be applied with a low bias voltage, and the permittivity of the base can be largely changed.

According to a fourth aspect of the present invention, in the second aspect, the first and second electrodes provided on the outer surface of the base so as to be in non-contact with the outer conductor and so as to be in non-contact with each other. A bias voltage is applied between the first electrode and the second electrode by control voltage generating means,
By applying an electric field to the base, the area of the first and second electrodes can be relatively widened, so that the dielectric constant of the base can be changed in a wide range.

According to a fifth aspect of the present invention, in the second aspect, a hole is provided in the base, an electrode is formed in the hole, and a control voltage generating means is provided between the electrode and another conductor or electrode. By applying an electric field to the base, the withstand voltage between the electrodes can be improved, and a sufficiently high voltage can be applied between the electrodes.

According to a sixth aspect of the present invention, in the second aspect, the resonator can be downsized by providing the through holes with portions having different diameters.

According to a seventh aspect of the present invention, with the provision of the second to fifth aspects, an insulating material for covering the electrodes is provided, so that the withstand voltage can be further improved.

Hereinafter, embodiments of the present invention will be described. (Embodiment 1) FIGS. 1 and 2 are a perspective view and a sectional view showing a dielectric resonator according to Embodiment 1 of the present invention.

1 and 2, reference numeral 10 denotes a base made of a material having a variable dielectric constant.
1 is formed. As the dielectric constant variable material, for example, a material whose dielectric constant changes by applying a bias voltage is selected. Specifically, a material which is an oxide represented by the chemical formula ABO ₃ , in which A contains at least one of Ba, Sr, Pb or a rare earth element, and B contains at least one selected from transition metal elements, Used. More specifically, BaTiO ₃ , SrTiO ₃ , B
aZrO ₃ , PbTiO ₃ , PbZrO ₃ , PbNbO ₃ ,
A material mainly composed of PbMnO ₃ , PbTaO ₃ , (Pb, La) TiO _3, or a material mainly composed of a solid solution thereof is used.

Reference numeral 12 denotes an inner conductor formed on the inner peripheral surface of the base 10, 13 denotes an outer conductor formed on the outer surface of the base 10, 19
Is a short-circuit conductor that electrically connects the inner conductor 12 and the outer conductor 20. Each of the inner conductor 12, the outer conductor 13, and the short-circuit conductor 19 is made of a single conductive material such as copper, solder, silver, gold, or aluminum, or an alloy thereof, or a laminated film of these metals. Alternatively, it is formed by a vapor deposition method, a sputtering method, or the like.

Reference numeral 15 denotes an electrode formed on the outer surface of the base 10. The electrode 15 is provided in a non-contact manner with the outer conductor 13 through a gap 14 formed so as to expose the base 10. I have.

Reference numeral 17 denotes an electrode formed on the inner side surface of the base 10. The electrode 17 is provided in a non-contact manner with the inner conductor 12 via a gap 16 formed so that the base is exposed. .

Reference numeral 18 denotes control voltage generating means for applying a predetermined bias voltage between the electrodes 15 and 17.

Reference numeral 20 denotes an electrode for input or output to an external circuit or the like. The electrode 20 is provided in non-contact with the outer conductor 13. When the center conductor (not shown) is brought into contact with the inner conductor 12 to make a connection with the outside, the electrode 20 becomes unnecessary.

It is preferable that the formation area of the electrode 15 and the formation of the electrode 17 be large.
This is because the electrode 15 formed on the outer surface having a large area can be formed with a larger area than the electrode 17 formed on the inner surface having a small area.
The volume of the base 10 sandwiched between the base 10 and the electrode 17 increases, the portion of the base 10 sandwiched between the electrode 15 and the electrode 17 becomes larger, the portion where the dielectric constant changes becomes larger, and the shift of the resonance frequency and the like increases. Becomes larger.

Further, it is preferable that the gaps 14 and 16 are formed wide (the gap L between the outer conductor 13 and the electrode 15).
1 and L2, the gap L between the inner conductor 12 and the electrode 17 is increased.
3, L4 is made wider). With such a configuration, the electrodes 15 and 17 to which a relatively high voltage is applied are provided.
Discharge or the like is unlikely to occur between each of them and the outer conductor 13 and the inner conductor 12, and a higher bias voltage can be applied between the electrodes 15 and 17.

Further, in order to further improve the insulation between the electrodes 15 and 17 and the outer conductor 13 and the inner conductor 12, respectively, at least an insulating material (epoxy) is formed on the electrodes 15 and 17 and the gaps 14 and 16. Means such as applying an insulating material such as resin).

Further, for example, if the space 14 is sufficiently wide and the space between the outer conductor 13 and the electrode 15 is widened, the space 16 is not required, and the electrode 15 and other conductors (the inner conductor 12, the outer conductor 13, Since an electric field is applied between the connecting conductors 19), the permittivity of the wider base 10 can be changed. Similarly, if the gap 16 is made wider and the inner conductor 12 and the electrode 17 are made wider, the gap 14 becomes unnecessary and the electrode 17
And other conductors (inner conductor 12, outer conductor 13, connecting conductor 19)
An electric field is applied during this period, and the dielectric constant of the base 10 can be changed in a wider range.

When a predetermined voltage is applied between the electrode 15 and the electrode 17 by the control voltage generating means 18, the electrode 1 on the base 10
The dielectric constant of the portion sandwiched between the electrode 5 and the electrode 17 and the vicinity thereof change according to the voltage, and the resonance frequency of the dielectric resonator can be shifted by this action. With such a configuration, the following effects can be obtained.

First, the dielectric constant of the portion sandwiched between the electrodes 15 and 17 of the base 10 and the vicinity thereof is changed by applying a bias voltage between the electrodes 15 and 17, and accordingly, the dielectric resonator is changed. Since the resonance frequency of the resonator can be changed, there is no need to design a dielectric resonator for each resonance frequency, and the components can be shared, so that the productivity of the dielectric resonator itself is improved. In addition, the productivity of products incorporating the dielectric resonator is improved. In other words, a dielectric resonator having a predetermined range can be obtained without changing the constituent materials and size of the dielectric resonator. It is not necessary to design the circuit, and even in an electronic device or the like on which the dielectric resonator is mounted, by keeping the mounting area constant, circuit design becomes easier and productivity is improved.

Also, depending on the temperature, the dielectric constant of the entire base 10 changes, which may cause a shift in the resonance frequency or the like.
As described above, by changing the dielectric constant of the portion of the base 10 sandwiched between the electrodes 15 and 17 and the vicinity thereof,
A stable resonance frequency or the like that does not depend on temperature changes can be obtained. At this time, the temperature of the place where the dielectric resonator is manufactured and the temperature of the place where the electronic device or the like incorporating the dielectric resonator is used are estimated to some extent, and the control voltage generating means 18 is used.
, A bias voltage to be applied between the electrodes 15 and 17 can be set in advance.

Further, by providing a temperature dependent sensor such as a thermistor in the control voltage generating means 18 and applying a bias voltage corresponding to the temperature to the electrodes 15 and 17,
A constant resonance frequency can always be obtained.

Further, in the first embodiment, the case where one dielectric resonator is used has been described, but a structure in which a plurality of dielectric resonators are joined may be used.

(Embodiment 2) FIGS. 3 and 4 are a perspective view and a sectional view, respectively, showing a dielectric resonator according to Embodiment 2 of the present invention.

3 and 4, reference numeral 21 denotes a base made of a material having a variable dielectric constant. The base 21 has a plurality of through holes 22 and 23 having a circular cross section. As the dielectric constant variable material, for example, barium titanate (BaTi
O ₃ ) -based material, Pb (Zr, Ti) O ₃ -based material, PbTi
An O ₃ -based material or the like is used alone or a material containing the material system is used. In the second embodiment, only a drawing provided with two through holes is described, but a base 21 provided with three or more through holes may be used.

Reference numerals 24 and 25 denote inner conductors respectively formed on the inner peripheral surface of the base 21, reference numeral 26 denotes an outer conductor formed on the outer surface of the base 21, and reference numeral 33 denotes the inner conductors 24 and 25 and the outer conductor 2.
6 is a short-circuit conductor that electrically connects them. Inner conductor 24, 2
5, the outer conductor 26 and the short-circuit conductor 33 are each made of a conductive material such as copper, solder, silver, gold, or aluminum, or an alloy thereof, or a laminated film of these metals, and are plated, dipped, or vapor-deposited. It is formed by a sputtering method or a sputtering method.

Reference numeral 28 denotes an electrode formed on the outer surface of the base 21, and the electrode 15 is provided in a non-contact manner with the outer conductor 26 through a gap 29 formed so as to expose the base 21. I have. The electrode 28 is formed so as to face the inner conductors 22 and 23, respectively. Note that the electrode 28 may be formed so as to face one of the inner conductors 22 and 23 depending on specifications and the like.

Reference numeral 30 denotes an electrode formed on the inner side surface of the base 21. The electrode 30 is provided in a non-contact manner with the inner conductor 24 through a gap 29 formed so that the base is exposed. . Although not shown, the inner conductor 24 in the through hole 23 also has an electrode provided with a gap from the inner conductor 24. Hereinafter, the electrode 30 and the inner conductor 24 are collectively referred to as electrodes 30 and the like provided through the gap.

Reference numeral 32 denotes control voltage generating means for applying a predetermined bias voltage between the electrode 28 and the electrode 30 and the like.

Reference numeral 31 denotes an electrode for input or output to an external circuit or the like. The electrode 31 is provided in non-contact with the outer conductor 26. When a center conductor (not shown) is brought into contact with the inner conductors 24 and 25 to make a connection with the outside, this electrode 31 is used.
Becomes unnecessary.

The control voltage generating means 32 applies an electric field between the electrode 28 and the electrode 30 and the like, and the base portion sandwiched between the electrode 28 and the electrode 30 and the like, as in the first embodiment. By changing the dielectric constant of the near luck, the resonance frequency and the like can be shifted, and the same effect as in the first embodiment can be obtained.

In particular, in the configuration as in the second embodiment, the distance between the electrode 28 and the electrode 30 and the like can be relatively narrowed, and the electrode 28 can be manufactured with a large area. Even if the bias voltage between the electrode 28 and the electrode 30 is lowered, a sufficiently large electric field can be applied to the base 21, and a larger change in the dielectric constant of the base 21 can be obtained.

As in the first embodiment, the gap 29
Covering the upper and electrode 28 with an insulating material (electrode 28
Is covered with an insulating material) to apply a higher voltage to the electrode 2.
8 and the electrode 30 or the like.

(Embodiment 3) FIGS. 5 and 6 are a perspective view and a sectional view showing a dielectric resonator according to Embodiment 3 of the present invention.

In FIGS. 5 and 6, reference numeral 21 denotes a base;
23 is a through hole, 24 and 25 are inner conductors, 26 is an outer conductor,
These have the same configuration as the second embodiment.

Reference numeral 41 denotes an electrode provided with a gap 40 and provided in non-contact with the outer conductor 26; 43, an electrode provided with a gap 42 and provided in non-contact with the inner conductor 24;
An electrode which is provided on the outer surface opposite to the outer surface provided with, and which is provided in a non-contact manner with the outer conductor 26 by providing a gap portion 44;
Reference numeral 47 denotes an electrode provided with a gap 46 and provided in non-contact with the inner conductor 25.

Reference numeral 48 denotes a control voltage generating means. The control voltage generating means 48 applies a bias voltage between the electrodes 41 and 43, and applies a bias voltage between the electrode 41 and the electrode 43 of the base 21 and the vicinity thereof. Changing the dielectric constant or applying a bias voltage between the electrodes 45 and 47 to change the dielectric constant of the portion of the base 21 sandwiched between the electrodes 45 and 47 and the vicinity thereof. Can be.

With such a configuration, depending on the specifications and the like,
The strength of the electric field applied between the electrode 41 and the electrode 43 and the strength of the electrode 45
By making the strength of the electric field applied between the electrode 47 and the electrode 47 different or the same, the characteristics such as the resonance frequency can be easily adjusted.

In the third embodiment, the electrodes 41, 4
3, 45 and 47 are located on the side close to the short-circuit conductor 33, but on the open end surface (the end surface where the dielectric is exposed).
And may be provided at an intermediate portion between the short-circuit conductor 33 and the open end face.

(Embodiment 4) FIGS. 7 and 8 are a perspective view and a sectional view showing a dielectric resonator according to Embodiment 4 of the present invention.

7 and 8, reference numeral 10 denotes a base, 11 denotes a through hole, 12 denotes an inner conductor, 13 denotes an outer conductor, and 19 denotes a short-circuit conductor, which are the same as those shown in the first embodiment.

Reference numeral 51 denotes an electrode provided in a non-contact manner with the outer conductor 13 via the gap 50, and reference numeral 54 denotes a electrode provided on a surface opposite to the outer peripheral surface on which the electrode 51 is provided. The outer conductor 13 is an electrode provided in a non-contact manner.

Reference numeral 52 denotes a control voltage generating means for applying a bias voltage to the electrodes 51 and 54 and applying an electric field to a portion of the base 10 sandwiched between the electrodes 51 and 54 and a portion in the vicinity thereof.

As described above, the electrodes 51 and 54 are provided on the outer surface.
As described in the first to third embodiments, it is not necessary to form an electrode for applying an electric field to the inner peripheral surface, so that the electrodes can be easily formed and the electrodes 51 and 54 having a relatively large area can be formed. Can be manufactured, the permittivity of the base in a wider range can be changed, and a larger change in the resonance frequency can be obtained.

(Fifth Embodiment) FIGS. 9 and 10 are a perspective view and a sectional view showing a dielectric resonator according to a fifth embodiment of the present invention.

9 and 10, reference numeral 21 denotes a base, 2
Reference numerals 2 and 23 denote through holes, 24 and 25 denote inner conductors, and 26 denotes outer conductors, which have the same configuration as in the second embodiment.

Reference numeral 61 denotes an electrode provided in a non-contact manner with the outer conductor 26 via the gap 60, and reference numeral 64 denotes an electrode provided on the outer surface opposite to the side on which the electrode 61 is provided. The outer conductor 26 is an electrode provided in a non-contact manner.

Reference numeral 62 denotes control voltage generating means for applying a bias voltage to the electrodes 61 and 64 and applying an electric field to a portion of the base 21 sandwiched between the electrodes 61 and 64 and a portion in the vicinity thereof.

As in the fourth embodiment, an electrode 61 is provided on the outer surface.
And the formation of the electrode 64,
As shown in FIG. 3, since it is not necessary to form an electrode for applying an electric field to the inner peripheral surface, the electrodes can be easily formed, and the electrodes 61 and 64 having a relatively large area can be manufactured. Can be changed, so that a larger change in resonance frequency can be obtained.

(Embodiment 6) FIGS. 11 and 12 are a perspective view and a sectional view, respectively, showing a dielectric resonator according to Embodiment 6 of the present invention.

11 and 12, reference numeral 10 denotes a base, 1
1 is a through hole, 12 is an inner conductor, 13 is an outer conductor, and 19 is a short-circuit conductor, which are the same as those in the first embodiment.

Numerals 70 and 71 are provided on the open end face of the base 10 so as to sandwich the through hole 11, and are rectangular holes in cross section. In the holes 70 and 71, conductors such as the outer conductor 13 are provided, respectively. The electrode 73 provided in non-contact with the layer,
74 are provided respectively.

Reference numeral 72 denotes a control voltage generating means for applying a bias voltage between the electrodes 73 and 74 and applying an electric field to a portion of the base 10 sandwiched between the electrodes 73 and 74 and a portion in the vicinity thereof.

In the case of the sixth embodiment, holes 70,
The electrodes 73 and 74 are provided in the holes 70 and 71, respectively.
And the control voltage generating means 7 is provided between the electrodes 73 and 74.
2, an electric field is applied, and by changing the dielectric constant of a portion to which the electric field is applied, the withstand voltage can be improved in addition to the effects described in the first to third embodiments. Since it can be added to the base 10, the change in the dielectric constant can be increased, and the shift range of the resonance frequency and the like can be widened.

In order to further increase the breakdown voltage between the electrodes 73 and 74, an insulating material (epoxy resin or the like) may be put in the holes 70 and 71, respectively.

Further, in the sixth embodiment, the holes 70 and 71 are provided so as to sandwich the through-hole 11. However, by providing the holes 70 and 71 independently between the through-hole 10 and the outer conductor 13, Since the distance between the electrodes 73 and 74 can be reduced, a stronger electric field can be applied to the region of the base 10 sandwiched between the electrodes 73 and 74, so that a larger change in the dielectric constant can be obtained. it can. By making the holes 70 and 71 through holes, the permittivity of the base 10 can be changed in a wider area.

In the sixth embodiment, two holes 70 and 71 are provided. However, one hole is formed and an electrode is formed in the hole, and the electrode and the outer conductor 13 or the inner conductor 12 are formed. Alternatively, an electric field may be applied to the base 10 between the short-circuit conductor 19 and the control voltage generating means 72, or the electrode may be contacted with the outer conductor 13, the inner conductor 12, or the short-circuit conductor 19 in a non-contact manner. An arrangement may be made in which an electric field is applied to the base 10 by the control voltage generating means 72 between the electrodes provided.

(Embodiment 7) FIGS. 13 and 14 are a perspective view and a sectional view, respectively, showing a dielectric resonator according to Embodiment 7 of the present invention.

13 and 14, reference numeral 21 denotes a base,
Reference numerals 22 and 23 denote through holes, reference numerals 24 and 25 denote inner conductors, reference numeral 26 denotes outer conductors, and reference numeral 33 denotes a short-circuit conductor. These have the same configuration as in the second embodiment.

Reference numerals 80 and 81 denote holes having a rectangular cross section provided on the base 21. The holes 80 and 81 are independently provided between the through holes 22 and 23.

Reference numerals 83 and 84 denote electrodes provided in the holes 80 and 81, respectively. The electrodes 83 and 84 are provided in non-contact with each other, and the outer conductor 26 and the inner conductors 24 and 25 are provided.
And the like are provided in a non-contact manner.

Reference numeral 82 denotes a control voltage generating means for applying a bias voltage between the electrodes 83 and 84 and applying an electric field to a portion of the base 21 sandwiched between the electrodes 83 and 84 and a portion in the vicinity thereof.

In the case of the seventh embodiment, similarly to the sixth embodiment, holes 80 and 81 are provided in base 21 and holes 80 and 81 are formed.
1, electrodes 83 and 84 are provided, and the electrodes 83 and 84 are provided.
By applying an electric field by the control voltage generating means 82 during that time and changing the dielectric constant of the portion to which the electric field is applied, the withstand voltage can be improved in addition to the effects shown in the first to third embodiments. Since a relatively high electric field can be applied to the base 21, the change in the dielectric constant can be increased, and the shift range of the resonance frequency and the like can be widened.

In order to further increase the withstand voltage between the electrodes 83 and 84, an insulating material (epoxy resin or the like) may be inserted into the holes 80 and 81, respectively.

Further, in the sixth embodiment, the holes 80 and 81 are provided so as to be sandwiched between the through hole 22 and the through hole 23.
By independently providing the hole 71 and the through hole 22 or the through hole 23 and the outer conductor 13, the interval between the electrode 83 and the electrode 84 can be narrowed. Since it can be added to the region sandwiched between 83 and 84, a larger change in the dielectric constant can be obtained. By making the holes 70 and 71 through holes, the permittivity of the base 10 can be changed in a wider area.

(Eighth Embodiment) FIGS. 15 and 16 are a perspective view and a sectional view, respectively, showing a dielectric resonator according to an eighth embodiment of the present invention.

15 and 16, reference numeral 10 denotes a base, 1
1 is a through hole, 12 is an inner conductor, 13 is an outer conductor, and 19 is a short-circuit conductor, which are the same as those in the first embodiment.

The difference from the first embodiment resides in the through hole 11. In the first embodiment, the thickness of the through-hole 11 is constant, but in the eighth embodiment, the through-hole 11 is configured by connecting a large-diameter hole 11a and a small-diameter hole 11b. . In the eighth embodiment, the diameter of the hole 11a on the open end side is made larger and the diameter of the hole 11b on the short-circuit end side is made smaller. May be increased in diameter.

Reference numeral 91 denotes an outer surface of the base 10 and the holes 11a
And the outer conductor 13 through the gap 90.
Is an electrode provided in a non-contact manner, and 94 is an inner surface of the base 10 and an electrode provided in a non-contact manner with the inner conductor 12 via the gap 93.

Reference numeral 92 denotes a control voltage generating means for applying a bias voltage between the electrode 91 and the electrode 94 and applying an electric field to the portion of the base 10 sandwiched between the electrode 91 and the electrode 94 and the vicinity thereof.

In the case of the eighth embodiment, the holes 11a and 11b having different diameters are connected to the through-hole 11, and the electrode 9 is formed in the large-diameter hole 11a (the thin portion of the base 10).
1 and 94, the control voltage generating means 92 applies an electric field between the electrodes 91 and 94, and changes the dielectric constant of the portion to which the electric field is applied. In addition to the advantageous effects, the withstand voltage can be improved, and a relatively high electric field can be applied to the base 10, so that the change in the dielectric constant can be increased and the shift range of the resonance frequency and the like can be increased. Can be. Further, by providing the through hole 11 with a step, the length and the like of the resonator can be shortened, so that the size can be reduced.

In the eighth embodiment, the electrodes 91 and 94 are provided on the thin portion of the base 10. However, the electrodes 91 and 94 are provided on the thick portion of the base 10 (the electrodes are provided in holes having a small diameter). Electrode 9
1, 94 may be provided.

Further, the so-called integral type dielectric resonator shown in the second embodiment exhibits the same effect by reducing the diameter of the through hole.

In the first to eighth embodiments, the electrode 1
5, 17, 28, 30, 41, 43, 45, 47, 5
1,54,61,64,73,74,83,84,9
Although the shapes of 1,94 were formed in a square shape, the concentration of the electric flux lines can be suppressed by rounding those corners, so that a short circuit between the electrode and the inner and outer conductors at the corners. Can be greatly suppressed and dielectric breakdown can be substantially suppressed, so that the distance between the electrode and the inner and outer conductors can be further reduced, and the size of the dielectric resonator can be reduced. Furthermore, by making the shape of the electrode itself circular or elliptical or an approximation thereof, the concentration of lines of electric force can be prevented more efficiently.

[0082]

According to the present invention, there is provided a conductive layer formed on a base made of a variable dielectric constant material, and a dielectric constant for changing the dielectric constant of the base by applying an external action to the base. By providing the variable means, it is possible to change the resonance frequency of the dielectric resonator, etc., so that it is possible to cover a certain resonance frequency without changing the shape, material, etc., so that the parts can be shared. In addition, productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a dielectric resonator according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a dielectric resonator according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a dielectric resonator according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a dielectric resonator according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing a dielectric resonator according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing a dielectric resonator according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing a dielectric resonator according to a fourth embodiment of the present invention.

FIG. 8 is a sectional view showing a dielectric resonator according to a fourth embodiment of the present invention.

FIG. 9 is a perspective view showing a dielectric resonator according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view showing a dielectric resonator according to a fifth embodiment of the present invention.

FIG. 11 is a perspective view showing a dielectric resonator according to a sixth embodiment of the present invention.

FIG. 12 is a sectional view showing a dielectric resonator according to a sixth embodiment of the present invention.

FIG. 13 is a perspective view showing a dielectric resonator according to a seventh embodiment of the present invention.

FIG. 14 is a sectional view showing a dielectric resonator according to a seventh embodiment of the present invention.

FIG. 15 is a perspective view showing a dielectric resonator according to an eighth embodiment of the present invention.

FIG. 16 is a sectional view showing a dielectric resonator according to an eighth embodiment of the present invention.

FIG. 17 is a perspective view showing a conventional dielectric resonator.

FIG. 18 is a sectional view showing a conventional dielectric resonator.

[Explanation of symbols]

10, 21 Base 11, 22, 23 Through-hole 12, 24, 25 Inner conductor 13, 26 Outer conductor 19, 33 Short-circuit conductor 15, 17, 28, 30, 41, 43, 45, 47, 5
1,54,61,64,73,74,83,84,9
1,94 electrodes 18,32,48,52,62,72,82,92 control voltage generating means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuyuki Nakajima 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (9)

[Claims] 1. A base made of a variable dielectric constant material, a conductor layer formed on the base, and an external action applied to the base to change the dielectric constant of the base. A dielectric resonator comprising: a dielectric constant varying unit. 2. A material having a dielectric constant changed by applying an electric field as a variable dielectric constant material, a through hole is provided in a base, and a conductive layer is formed on an outer conductor provided on an outer surface of the base with the outer conductor. An inner conductor provided on the inner surface of the base, a connecting conductor for connecting the outer conductor and the inner conductor, and the inner conductor, the outer conductor, and the short-circuit conductor are provided with electrodes provided in a non-contact manner,
2. The dielectric resonator according to claim 1, wherein a control voltage generating unit is used as the dielectric constant varying unit, and an electric field is applied to the base through the control voltage generating unit using the electrode. A first electrode provided on the outer surface of the base in non-contact with the outer conductor; and a second electrode provided on the inner surface of the base in non-contact with the inner conductor, 3. The dielectric resonator according to claim 2, wherein a bias voltage is applied between said first electrode and said second electrode by a control voltage generating means to apply an electric field to said base. And a first electrode and a second electrode provided on the outer surface of the base so as to be in non-contact with the outer conductor and to be in non-contact with each other, respectively. 3. The dielectric resonator according to claim 2, wherein a bias voltage is applied between the two electrodes by a control voltage generating means to apply an electric field to the base. 5. A base is provided with a hole, an electrode is formed in the hole, and an electric field is applied to the base between the electrode and another conductor or electrode by a control voltage generating means. The dielectric resonator according to claim 2. 6. The dielectric resonator according to claim 2, wherein portions having different diameters are provided in the through holes. 7. The dielectric resonator according to claim 2, further comprising an insulating material covering the electrode. 8. The dielectric resonator according to claim 2, wherein the electrode is formed in a square shape, and a corner of the electrode is rounded. 9. The dielectric resonator according to claim 2, wherein the electrode is formed in a circular or elliptical shape.