JP7699963B2 - DISC RESONATOR, CONDUCTIVITY MEASURING APPARATUS, AND CONDUCTIVITY MEASURING METHOD - Google Patents

Description

The present invention relates to a disk resonator, a conductivity measuring device, and a conductivity measuring method.

In recent years, efforts have been made to utilize millimeter wave electromagnetic waves, which have higher frequencies than the microwave band. Electronic devices that use millimeter wave electromagnetic waves use high-frequency circuit boards that are compatible with the millimeter wave band. Reducing the transmission loss of high frequencies is an issue for such high-frequency circuit boards.

Against this background, the development of low-loss materials that are compatible with high frequencies such as the millimeter wave band is underway. In addition, there is a demand for technology that can measure the conductivity of low-loss materials in the high frequency range with high precision, which is necessary for this purpose. The disk resonator method is known as one such technology.

Patent Document 1 discloses a method for measuring the specific conductivity of a conductor plate or copper foil in the high frequency range exceeding 20 GHz using a disk resonator. Specifically, the disk resonator described in Patent Document 1 comprises a circular copper foil, a first dielectric plate and a second dielectric plate sandwiching the copper foil, and a first conductor plate and a second conductor plate sandwiching them. Each conductor plate has a hole in the center, into which an excitation wire is inserted.

When a specific frequency is transmitted from the network analyzer, the resonator is excited via the excitation line. Then, by analyzing the signal received from the resonator, the specific conductivity of the conductor plate or copper foil can be determined.

In the method described in Patent Document 1, materials having different thicknesses are prepared as the first and second dielectric plates. Specifically, a first output result is obtained using the first and second dielectric plates having a thickness of _t1 . Next, a second output result is obtained using the first and second dielectric plates having a thickness of _t2 . Finally, the specific conductivity is calculated based on the first and second output results.

JP 2020-180807 A

In the method described in Patent Document 1, it is necessary to obtain measurement results for dielectric plates of different thicknesses, so the measurement work needs to be performed at least twice. For this reason, the method described in Patent Document 1 has the problem of low efficiency of the measurement work.

The object of the present invention is to provide a disk resonator, a conductivity measuring device, and a conductivity measuring method that can efficiently measure conductivity in the high frequency range.

These objects can be achieved by the present invention described below in (1) to (17).
(1) a first support for supporting a first conductor sample;
a second support provided opposite to the first support and configured to support a second conductor sample;
a third support that supports the third conductor sample such that a gap filled with outside air is formed between the first conductor sample and the third conductor sample, and between the second conductor sample and the third conductor sample, respectively;
a signal transmitting/receiving unit configured to transmit and receive signals to and from the first conductor sample, the second conductor sample, and the third conductor sample;
A disk resonator comprising:

(2) A disk resonator as described in (1) above, having a distance change unit that changes the first distance d1 between the first conductor sample and the third conductor sample, and the second distance d2 between the second conductor sample and the third conductor sample.

(3) The distance change unit
a shaft having a screw on a side surface thereof and rotating about an axis of rotation;
a stand that rotatably supports the shaft;
Equipped with
The disk resonator according to (2) above, wherein any two of the first support, the second support, and the third support move in response to rotation of the shaft.

(4) The screw has a first portion that moves the first support and a second portion that moves the second support,
The disk resonator according to the above (3), wherein the direction of advance of the screw in the first portion and the direction of advance of the screw in the second portion are opposite to each other.

(5) The screw has a third portion that moves the second support and a fourth portion that moves the third support,
a thread advance direction of the third portion and a thread advance direction of the fourth portion are the same as each other,
The disk resonator according to the above (3), wherein the pitch of the thread of the third portion is larger than the pitch of the thread of the fourth portion.

(6) The distance change unit
a rail extending parallel to a straight line passing through both the first conductor sample and the second conductor sample;
a first slider and a second slider that move along the rail;
Equipped with
The disk resonator according to (2) above, wherein two of the first support, the second support and the third support are connected to the first slider and the second slider.

(7) A first through hole extending parallel to a line passing through both the first conductive sample and the second conductive sample and penetrating the first support,
The disk resonator according to any one of (1) to (6) above, wherein the signal transmitting/receiving unit includes a first through excitation line inserted into the first through hole.

(8) A second through hole extending parallel to the straight line and penetrating the second support,
The disk resonator according to (7) above, wherein the signal transmitting/receiving unit includes a second through excitation line inserted into the second through hole.

(9) A disk resonator according to any one of (1) to (6) above, in which the signal transmitting/receiving unit includes a lateral excitation line that is inserted between the first conductor sample and the second conductor sample from a direction that intersects with a straight line that passes through both the first conductor sample and the second conductor sample.

(10) The third support is
A first frame having a frame shape;
a dielectric member provided inside the first frame and connecting the first frame and the third conductor sample;
The disk resonator according to any one of (1) to (9) above, comprising:

(11) The third support is
a second frame provided outside the first frame;
a position adjustment unit that adjusts a position of the first frame relative to the second frame;
The disk resonator according to (10) above, comprising:

(12) The third support is structurally independent from the first support and the second support,
The disk resonator according to (2) above, wherein the distance change unit changes at least one of the first distance d1 and the second distance d2 by moving at least one of the first support and the second support to change the separation distance between the first support and the second support.

(13) The disk resonator according to (2), (6) or (12) above, in which the distance changer changes the first distance d1 and the second distance d2 while maintaining the orientation of the second conductor sample relative to the first conductor sample.

(14) The third support includes a third a member and a third b member each having a through gap and having an equal thickness, the third a member, the third conductor sample, and the third b member are stacked in this order and sandwiched between the first support and the second support to support the third conductor sample,
When the third conductor sample is supported by the third support,
the gap portion of the third a member is located between the first conductive sample and the third conductive sample,
The disk resonator according to (2) above, wherein the gap portion of the third b member is located between the second conductive sample and the third conductive sample.

(15) A conductivity measuring device comprising a disk resonator according to any one of (1) to (14) above.

(16) A conductivity measuring method for measuring the conductivity of a first conductor sample, a second conductor sample, and a third conductor sample by a balanced disk resonator method, comprising:
a sample arrangement step of arranging the first conductive sample, the second conductive sample, and the third conductive sample such that gaps filled with outside air are formed between the first conductive sample and the third conductive sample, and between the second conductive sample and the third conductive sample, respectively;
a measuring step of transmitting signals to the first conductor sample, the second conductor sample, and the third conductor sample, and receiving signals from the first conductor sample, the second conductor sample, and the third conductor sample;
A calculation step of analyzing the received signal and calculating the conductivity;
A method for measuring electrical conductivity comprising the steps of:

(17) The conductivity measurement method described in (16) above, in which the signal to be transmitted is a high-frequency signal having a frequency of 300 MHz or more.

The present invention provides a disk resonator and a conductivity measuring device that can efficiently measure conductivity in the high frequency range.

The present invention also provides a conductivity measurement method that can efficiently measure conductivity in the high frequency range.

FIG. 1 is a cross-sectional view showing a disk resonator according to a first embodiment. FIG. 11 is a perspective view showing a second configuration example of the third support; FIG. 3 is a plan view of the third support shown in FIG. 2 . FIG. 11 is a plan view showing a third configuration example of the third support; FIG. 13 is a plan view showing a fourth configuration example of the third support. This is a graph created by plotting the measurement results when the horizontal axis of a Cartesian coordinate system represents the reciprocal of the gap distance and the vertical axis represents the reciprocal of the Q value. 11A to 11C are cross-sectional views for explaining a procedure for measuring electrical conductivity using a disk resonator. 11A to 11C are cross-sectional views for explaining a procedure for measuring electrical conductivity using a disk resonator. FIG. 11 is a cross-sectional view showing a disk resonator according to a second embodiment. FIG. 11 is a cross-sectional view showing a disk resonator according to a third embodiment. FIG. 13 is a cross-sectional view showing a disk resonator according to a fourth embodiment. FIG. 13 is a cross-sectional view showing a disk resonator according to a fifth embodiment. FIG. 13 is a diagram showing a conductivity measuring device according to a sixth embodiment. 13 is a flowchart showing a conductivity measuring method according to a seventh embodiment.

The following describes in detail the disc resonator, conductivity measuring device, and conductivity measuring method of the present invention based on the preferred embodiments shown in the attached drawings.

1. First Embodiment First, a circular disk resonator according to a first embodiment will be described.

Figure 1 is a cross-sectional view showing a disk resonator according to the first embodiment. In each figure of the present application, an X-axis, a Y-axis, and a Z-axis are set as three mutually orthogonal axes, and are indicated by arrows. The base end side of the arrows is called the "negative side" of each axis, and the tip end side of the arrows is called the "positive side" of each axis.

The disk resonator 1 shown in Figure 1 is a tool used to measure the conductivity of conductor samples 91, 92, and 93 using the balanced disk resonator method.

The disk resonator 1 shown in FIG. 1 holds the first conductor sample 91, second conductor sample 92, and third conductor sample 93 to be measured with a gap between them. When a high-frequency signal is sent to the disk resonator 1 with the third conductor sample 93 placed between the first conductor sample 91 and the second conductor sample 92, only a specific resonance mode is selectively excited. By measuring the resonance characteristics with a measuring device such as a network analyzer, the conductivity at each resonance frequency can be obtained.

The first conductor sample 91, the second conductor sample 92, and the third conductor sample 93 each have a circular flat plate shape in a plan view. The first conductor sample 91 and the second conductor sample 92 have the same diameter and a larger diameter than the third conductor sample 93. The concept of having equal diameters is that deviations of the order of manufacturing errors are tolerated. In this specification, "plan view" refers to a view from a position on the Z axis. The first conductor sample 91, the second conductor sample 92, and the third conductor sample 93 are samples made of the same conductor.

The disc resonator 1 can be used to measure electrical conductivity in the high frequency range. Since electrical conductivity can be frequency dependent, accurate measurement of electrical conductivity in the high frequency range is important, for example, in the development of circuits that use high frequency radio waves (high frequency circuits).

The structure of the disk resonator 1 will be further described below. The disk resonator 1 has a first support 21, a second support 22, a third support 23, a signal transmitting/receiving unit 5, and a distance changing unit 6.

1.1. Support Body The first support body 21 includes a first supporting conductor plate 212 and a first fixing plate 214 .

The first supporting conductor plate 212 is a member that supports the first conductor sample 91 to be measured so that it spreads along the X-Y plane, and in this embodiment, it is in the form of a plate that spreads along the X-Y plane. The first supporting conductor plate 212 is electrically connected to the first conductor sample 91 to be measured. The shape of the first supporting conductor plate 212 in a plan view is not particularly limited, but in this embodiment, it is a rectangle. The size of the first supporting conductor plate 212 in a plan view is set to be larger than the first conductor sample 91.

The first fixed plate 214 is a plate extending along the XY plane. The first fixed plate 214 supports the first supporting conductor plate 212. The planar shape of the first fixed plate 214 is not particularly limited, but in this embodiment it is rectangular.

The second support 22 is disposed opposite the first support 21 and includes a second support conductor plate 222 and a second fixing plate 224.

The second supporting conductor plate 222 is a member that supports the second conductor sample 92 to be measured so that it spreads along the X-Y plane, and in this embodiment, it is in the form of a plate that spreads along the X-Y plane. The second supporting conductor plate 222 is electrically connected to the second conductor sample 92 to be measured. The shape of the second supporting conductor plate 222 in a plan view is not particularly limited, but in this embodiment, it is a rectangle. The size of the second supporting conductor plate 222 in a plan view is set to be larger than that of the second conductor sample 92.

The second fixed plate 224 is a plate extending along the XY plane. The second fixed plate 224 supports the second supporting conductor plate 222. The planar shape of the second fixed plate 224 is not particularly limited, but in this embodiment it is rectangular.

The constituent materials of the first supporting conductor plate 212 and the second supporting conductor plate 222 are not particularly limited as long as they are materials having sufficient conductivity, and examples include copper alone or a copper alloy, aluminum alone or an aluminum alloy, a silver alloy, and a nickel alloy. In addition, the first supporting conductor plate 212 and the second supporting conductor plate 222 may be made of a composite material in which a coating of the aforementioned conductive material, such as a plating film, is provided on the surface of an insulating base material. The constituent materials of the first supporting conductor plate 212 and the second supporting conductor plate 222 may be different from each other, but are preferably the same from each other.

The constituent materials of the first fixing plate 214 and the second fixing plate 224 are not particularly limited as long as they have sufficient mechanical strength, and examples of such materials include metal materials such as stainless steel, heat-resistant steel, tool steel, Fe-based alloys such as mechanical structural alloy steel, Cu-based alloys such as brass, aluminum alloys, and ceramic materials such as alumina and zirconia. The constituent materials of the first fixing plate 214 and the second fixing plate 224 may be different from each other, but are preferably the same. Furthermore, the first fixing plate 214 and the second fixing plate 224 may be provided as necessary, and may be omitted.

The joint between the first supporting conductor plate 212 and the first fixed plate 214, and the joint between the second supporting conductor plate 222 and the second fixed plate 224 may be simply in close contact, or may be bonded via an adhesive or the like.

Note that if the first conductor sample 91 is self-supporting relative to the first slider 65 described below, the first support 21 may be omitted. Similarly, if the second conductor sample 92 is self-supporting relative to the second slider 66 described below, the second support 22 may be omitted.

The third support 23 includes a first frame 232 and a dielectric member 234 .
The first frame 232 has a frame shape larger than the third conductive sample 93 to be measured. The first frame 232 supports the third conductive sample 93 via a dielectric member 234 to be described later.

The dielectric member 234 is in the form of a plate extending along the XY plane, and has a through hole 235 in the center. The third conductor sample 93 is fixed so as to cover this through hole 235. In this way, the third conductor sample 93 is supported by the first frame 232 via the dielectric member 234.

The thickness of the dielectric member 234 is not particularly limited, but is preferably 0.001 mm to 1.00 mm, and more preferably 0.02 mm to 0.50 mm. With such a thickness, the electrical resistance per unit length of the dielectric member 234 in the plane becomes high, so that the insulation between the third conductor sample 93 and the first frame 232 can be ensured.

The material of the first frame 232 is not particularly limited as long as it has sufficient mechanical strength.

The material of the dielectric member 234 is not particularly limited as long as it has a low dielectric constant and dielectric tangent, but examples include polyethylene, cycloolefin polymer, fluororesin, quartz, etc.

The third support 23 is disposed so as to leave a gap between the first support 21 and the second support 22. This gap electrically insulates the first conductor sample 91 from the third conductor sample 93, and the second conductor sample 92 from the third conductor sample 93.

As described above, the third support 23 shown in FIG. 1 includes the frame-shaped first frame 232 and the dielectric member 234. The dielectric member 234 is provided inside the first frame 232 and connects the first frame 232 and the third conductor sample 93.

This configuration makes it possible to sufficiently reduce the change in the electromagnetic field when there is air between the first frame 232 and the third conductor sample 93, and also makes it possible to easily hold the third conductor sample 93. In addition, by increasing the rigidity of the first frame 232, the third support 23 becomes easier to handle.

Figure 2 is a perspective view showing a second configuration example of the third support. Figure 3 is a plan view of the third support 23 shown in Figure 2. Note that the first frame 232 is omitted from Figure 2.

In the third support 23 shown in FIG. 1, a third conductor sample 93 of approximately the same size is fitted into the through hole 235 provided in the dielectric member 234. If such a configuration example of the third support 23 is referred to as a "first configuration example," FIGS. 2 and 3 show a second configuration example that is different from the first configuration example.

In the third support 23A shown in Figures 2 and 3, the size of the through hole 235 is set smaller than that of the third conductor sample 93. This causes the outer periphery of the third conductor sample 93 and the dielectric member 234 to overlap. This allows the two overlapping members to be fixed together using an adhesive or glue, making the fixing process easier.

FIG. 4 is a plan view showing a third configuration example of the third support.
The third support 23B shown in FIG. 4 includes, in addition to the first frame 232 and the dielectric member 234, a second frame 238, two micrometer heads 242X, 242Y, two coil springs 246X, 246X, and two coil springs 246Y, 246Y.

The second frame 238 is frame-shaped and is provided on the outside of the first frame 232. A gap is provided between the first frame 232 and the second frame 238, and coil springs 246X, 246X, 246Y, and 246Y are provided in the gap.

Coil springs 246X, 246X connect the first frame 232 and the second frame 238 and expand and contract along the X-axis. Coil springs 246Y, 246Y connect the first frame 232 and the second frame 238 and expand and contract along the Y-axis.

The micrometer heads 242X and 242Y each include a sleeve 243 and a spindle 244. The spindle 244 can be inserted into and removed from the sleeve 243, and the insertion length into the sleeve 243 can be finely adjusted. The sleeve 243 is connected to the second frame 238, and the spindle 244 is connected to the first frame 232.

By inserting and removing the spindle 244 into and from the sleeve 243 of the micrometer head 242X, the position of the first frame 232 along the X-axis relative to the second frame 238 can be finely adjusted. By inserting and removing the spindle 244 into and from the sleeve 243 of the micrometer head 242Y, the position of the first frame 232 along the Y-axis relative to the second frame 238 can be finely adjusted. Therefore, the micrometer heads 242X and 242Y function as a position adjustment unit that adjusts the position of the first frame 232 relative to the second frame 238.

By using the position adjustment unit, the third support 23B can finely adjust the position of the third conductor sample 93 in the XY plane. This allows the position of the third conductor sample 93 relative to the positions of the first conductor sample 91 and the second conductor sample 92 to be optimized, thereby further improving the accuracy of the conductivity measurement.

The coil springs 246X and 246Y can be replaced with any elastic material, such as rubber, elastomer, or springs other than coil springs.

FIG. 5 is a plan view showing a fourth configuration example of the third support.
The third support 23C shown in Fig. 5 is similar to the third support 23A shown in Fig. 3 except for the configuration of the dielectric member. That is, the third support 23C includes three dielectric members 234C shown in Fig. 5 instead of the dielectric member 234 shown in Fig. 3. The dielectric members 234C are strip-shaped and are arranged around the third conductor sample 93 at equal angular intervals. This allows the area of the dielectric members 234C to be smaller than that of the dielectric member 234. As a result, the change in the electromagnetic field when there is air between the third support 23C and the third conductor sample 93 can be further reduced, thereby further improving the measurement accuracy of the conductivity.

1 includes a transmitting antenna 55 having a first through-hole excitation wire 51 and a holder 53, and a receiving antenna 56 having a second through-hole excitation wire 52 and a holder 54.

One end of a transmission cable (not shown) is connected to the first through excitation wire 51. The other end of this transmission cable is connected to the output port of a measurement device such as a network analyzer (not shown).

One end of a receiving cable (not shown) is connected to the second through excitation line 52. The other end of this receiving cable is connected to an input port of a measuring device such as a network analyzer (not shown).

When the electromagnetic waves (signals) supplied from the network analyzer to the transmitting antenna 55 are transmitted to the disk resonator 1, the resonance mode originating from the conductor samples 91, 92, and 93 is excited. The electromagnetic waves that have passed through the resonator consisting of the conductor samples 91, 92, and 93 are then picked up by the receiving antenna 56 and detected by the network analyzer. By analyzing the resonance characteristics from the detected electromagnetic waves, it is possible to calculate the Q value (resonance quality factor), which indicates the sharpness of the resonance characteristics. The conductivity of the first conductor sample 91, the second conductor sample 92, and the third conductor sample 93 can then be calculated from this Q value.

The first through excitation wire 51 extends along the first axis AX1 shown in FIG. 1. The first axis AX1 is parallel to the Z axis, passes through the center of the first conductor sample 91 in a plan view, and is located on the positive side of the Z axis relative to the first conductor sample 91. The first conductor sample 91, the first supporting conductor plate 212, and the first fixing plate 214 each have a first through hole 216 extending along the first axis AX1. The first through excitation wire 51 is inserted through the first through hole 216. This allows a high-frequency signal to be supplied from the first through excitation wire 51 to the first conductor sample 91.

The holder 53 is disposed on the positive side of the Z axis of the first fixed plate 214. The holder 53 also has a through hole 532 through which the first through excitation wire 51 passes. This allows the holder 53 to hold the first through excitation wire 51.

The second through excitation wire 52 extends along the second axis AX2 shown in FIG. 1. The second axis AX2 is parallel to the Z axis, passes through the center of the second conductor sample 92 in a plan view, and is located on the negative Z axis side of the second conductor sample 92. The second conductor sample 92, the second supporting conductor plate 222, and the second fixing plate 224 each have a second through hole 226 extending along the second axis AX2. The second through excitation wire 52 is inserted through the second through hole 226. This allows the second through excitation wire 52 to receive a signal from the second conductor sample 92.

The holder 54 is disposed on the negative Z-axis side of the second fixed plate 224. The holder 54 also has a through hole 542 through which the second through excitation wire 52 passes. This allows the holder 54 to hold the second through excitation wire 52.

The first through excitation line 51 and the second through excitation line 52 can be made of various types of waveguides that propagate electromagnetic waves of the measurement frequency, such as coaxial lines, planar circuit type lines, waveguides, and dielectric waveguides.

In this embodiment, the signal transmission/reception unit 5 includes a transmission antenna 55 and a reception antenna 56, but only one of the antennas may be used. In other words, signals may be transmitted and received using a single antenna.

1 includes a stand 61, a shaft 62, a handle 63, a rail 64, a first slider 65, a second slider 66, and a base 67. The distance changer 6 has a function of moving the first support 21 and the second support 22 closer to or farther away from the third support 23. With this function, it is possible to change the distance between the first conductive sample 91 and the third conductive sample 93 (first distance d1) and the distance between the second conductive sample 92 and the third conductive sample 93 (second distance d2).

The stand 61 comprises a base 612 and walls 614 and 616. The base 612 is a portion extending along the Z axis. The wall 614 is a portion extending from the end of the base 612 on the positive side of the Z axis toward the positive side of the Y axis. The wall 616 is a portion extending from the end of the base 612 on the negative side of the Z axis toward the positive side of the Y axis. The wall 614 is provided with an insertion hole 615. The wall 616 is provided with an insertion hole 617.

The shaft 62 is cylindrical and extends along the Z axis. The end of the shaft 62 on the positive side of the Z axis is inserted into the insertion hole 615. The end of the shaft 62 on the negative side of the Z axis is inserted into the insertion hole 617. The shaft 62 is rotatable about a rotation axis AX3 parallel to the Z axis with respect to the insertion holes 615 and 617.

The shaft 62 has a screw 620 on the side. The screw 620 is a male screw.

The handle 63 is connected to the end of the shaft 62 on the positive side of the Z axis. The handle 63 is the point of force that applies a rotational force to the shaft 62 to rotate it around the rotation axis AX3. The handle 63 can be replaced with a power source such as an electric motor.

The rail 64 is a portion that extends along the Z axis. The first slider 65 and the second slider 66 are guided by the rail 64 and are movable along the Z axis. The first support 21 described above is fixed to the first slider 65. The first slider 65 is provided with an insertion hole 652 through which the shaft 62 is inserted. The second support 22 is fixed to the second slider 66. The second slider 66 is provided with an insertion hole 662 through which the shaft 62 is inserted. The insertion holes 652 and 662 are each provided with a female screw (not shown).

Note that some or all of the stand 61, shaft 62, handle 63, rail 64, and first slider 65 and second slider 66 can be replaced with an electric actuator such as a linear slider.

The screw 620 described above has a first part 621 and a second part 622 that move in opposite directions. The first part 621 screws into the female thread provided in the insertion hole 652, and the second part 622 screws into the female thread provided in the insertion hole 662. Therefore, when the handle 63 is turned to rotate the shaft 62 around the rotation axis AX3, the first slider 65 and the second slider 66 move in opposite directions. This makes it possible to change the first distance d1 and the second distance d2 in conjunction with each other simply by turning the handle 63.

The base 67 is a portion that connects the stand 61 and the third support 23. The base 67 is provided with an insertion hole 672 through which the shaft 62 is inserted. In the distance change unit 6 shown in FIG. 1, the screw 620 is not screwed into the insertion hole 672.

1.4 Measurement Principle Next, the principle of measuring the conductivity of the conductor samples 91, 92, and 93 will be described.

The disc resonator 1 can be used to measure the conductivity of the conductor samples 91, 92, and 93, but in particular, by transmitting a high-frequency signal, it is possible to measure the conductivity in the high-frequency range.

One of the purposes of measuring conductivity in the high frequency range is to reduce transmission loss in high frequency circuits. Reducing transmission loss in high frequency circuits can contribute to the miniaturization, high functionality, and power saving of devices that use high frequency circuits.

Transmission loss is mainly divided into dielectric loss and conductor loss. Of these, the conductivity measured by the disk resonator 1 affects the conductor loss. Specifically, conductor loss depends on the frequency of the signal used in the high-frequency circuit, the conductivity of the conductor, and the circuit shape, and it is inevitable that conductor loss increases as the frequency increases. For this reason, in the high-frequency range, it is necessary to increase the conductivity as much as possible.

In the high frequency range, the skin effect makes it easier for current to flow near the surface of a conductor. If the surface of a conductor is rough, the conductivity decreases. Also, the surface of a conductor may be made rough to increase the adhesive strength between the conductor and the insulating substrate. For this reason, when measuring conductivity using the disc resonator 1, it is necessary to measure conductivity that reflects the influence of the skin effect.

Therefore, when attaching a conductor sample to the disk resonator 1, the attachment method is selected according to the type of conductor sample.

If there is no distinction between the front and back of the conductor sample to be measured, for example if the conductor sample to be measured is a rolled metal foil, conductor samples 91, 92, and 93 may all be the same sample.

In contrast, when the conductor sample to be measured has a front and back, for example when the conductor sample to be measured is an electrolytic metal foil, electrolytic metal foil is used for the first conductor sample 91 and the second conductor sample 92, and rolled metal foil is used for the third conductor sample 93. When placing the first conductor sample 91 and the second conductor sample 92, the surface to be measured, for example the surface that has been roughened, is placed facing the third conductor sample 93.

When the above-mentioned conductor samples 91, 92, and 93 are attached to the disk resonator 1 and measurements are performed, as described above, the Q value (resonance quality factor) that indicates the sharpness of the resonance characteristics of the disk resonator 1 is obtained. This Q value is expressed by the following formula (1).

In the above formula (1), _Qd is a dielectric Q value due to dielectric loss, and _Qc is a conductor Q value due to conductor loss. Among them, _Qd has the relationship of the following formula (2).

In the above formula (2), tan δ is the dielectric tangent of the dielectric provided between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93.

On the other hand, in the case of a disk resonator in which the first distance d1 and the second distance d2 are equal, that is, a balanced disk resonator, _Qc in the above formula (1) has the relationship of the following formula (3).

In the above equation (3), σ is the conductivity of the conductor samples 91, 92, and 93, d is the gap distance, i.e., the first distance d1 and the second distance d2, which are equal to each other, ω is the angular frequency of the signal transmitted to the disk resonator 1, and μ is the magnetic permeability of a vacuum.
Then, the following formula (4) is derived from the above formulas (1) to (3).

In this embodiment, a gap is provided between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93. Therefore, tan δ in the above formula (2) is the dielectric tangent of the outside air (air) and is zero. As a result, the above formula (4) is simplified to the following formula (5).

In the case of a disk resonator in which the first distance d1 and the second distance d2 are different, i.e., an unbalanced disk resonator, equation (5) is corrected as shown in equation (6) below.

In the above formula (6), α is a correction coefficient equal to or greater than 1, and d _ave is the average value of the first distance d1 and the second distance d2, that is, d _ave =(d1+d2)/2.

Here, in the above formula (5), the inverse of the Q value of the disk resonator 1 is proportional to the inverse of the gap distance.

Figure 6 is a graph created by plotting the measurement results when the horizontal axis of the Cartesian coordinate system is the inverse of the gap distance d and the vertical axis is the inverse of the Q value. By utilizing the proportional relationship described above, the conductivity included in the proportionality coefficient can be calculated. In other words, the conductivity can be calculated from the slope of the straight line connecting the plot mark P on the graph and the origin of the Cartesian coordinate system.

This straight line can be drawn if there is at least one plot mark P. Some conventional measurement methods require at least two plot marks, that is, at least two measurement operations, but in this embodiment, the conductivity is found in a single measurement operation. Therefore, by using the disk resonator 1, the efficiency of the measurement operation can be improved.

The conductivity calculated from the slope of the straight line is the average of the conductivity of the conductor samples 91, 92, and 93. Therefore, if the conductor sample being measured is, for example, the electrolytic metal foil described above, the average of the conductivity of the electrolytic metal foil and the conductivity of the rolled metal foil is calculated. In this case, by using a rolled metal foil with a known conductivity, the conductivity of the electrolytic metal foil being measured can finally be calculated.

The number of plot marks P is not limited to one, and may be multiple. By deriving a straight line that approximates multiple plot marks P and determining the slope, the conductivity can be calculated with greater precision. According to the disk resonator 1 of this embodiment, the first distance d1 and the second distance d2 can be easily changed, so that the measurements required for multiple plot marks P can be efficiently performed.

As described above, the disk resonator 1 according to this embodiment has the first support 21, the second support 22, the third support 23, and the signal transmitting/receiving unit 5. The first support 21 supports the first conductor sample 91. The second support 22 is provided opposite the first support 21 and supports the second conductor sample 92. The third support 23 supports the third conductor sample 93 so that there is a gap between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93. The signal transmitting/receiving unit 5 transmits and receives signals to and from the first conductor sample 91, the second conductor sample 92, and the third conductor sample 93.

With this configuration, the conductivity of the conductor sample can be determined with at least one measurement operation. Therefore, the disc resonator 1 can efficiently measure conductivity in the high frequency range.

In addition, by providing a gap between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93, there is no need to fill the gaps with a dielectric. This allows the number of parts in the disk resonator 1 to be reduced, making it easier to handle.

Furthermore, with the disk resonator 1, the conductive sample is not damaged or deformed, such as by denting, due to contact with the dielectric. This allows for more accurate measurement of the conductivity of the conductive sample, including the effects of the skin effect.

In addition, the disk resonator 1 allows the selection of the gas that enters the gap, so it is possible to investigate, for example, the effects of humidity and gas composition on electrical conductivity. This allows the relationship between electrical conductivity and various environmental factors to be evaluated.

As described above, the disk resonator 1 according to this embodiment has a distance change unit 6. The distance change unit 6 has the function of changing the first distance d1 between the first conductor sample 91 and the third conductor sample 93, and the second distance d2 between the second conductor sample 92 and the third conductor sample 93.

With this configuration, the first distance d1 and the second distance d2 can be easily adjusted according to the frequency of the signal transmitted to the disk resonator 1. Specifically, if the first distance d1 and the second distance d2 are large, the desired resonance peak cannot be obtained at a high frequency. On the other hand, if the first distance d1 and the second distance d2 are small, the Q value decreases, and may deviate from the range in which it can be calculated with high accuracy. For this reason, if the first distance d1 and the second distance d2 can be easily adjusted according to the frequency of the signal and the measurement accuracy, it is useful in that it makes the measurement operation of the conductivity easier. In addition, the measurements required to identify multiple plot marks P can be easily performed.

The first distance d1 and the second distance d2 may be different from each other, but are preferably set to be equal to each other. This allows the Q value to be determined with high accuracy, and the conductivity to be calculated with higher accuracy. The difference |d1-d2| between the first distance d1 and the second distance d2 is preferably 30% or less of the shorter of the first distance d1 and the second distance d2, and more preferably 20% or less. With a difference of this magnitude, the conductivity can be determined with relatively high accuracy by correcting the measurement results.

The first distance d1 and the second distance d2 are set according to the frequency of the signal transmitted to the disk resonator 1, but as an example, they are preferably 100 μm or more and 500 μm or less, and more preferably 200 μm or more and 400 μm or less.

As described above, the distance change unit 6 shown in FIG. 1 includes the shaft 62 and the stand 61. The shaft 62 has a screw 620 provided on the side and rotates around the rotation axis AX3. The stand 61 supports the shaft 62 in a rotatable state. Any two of the first support 21, the second support 22, and the third support 23 are configured to move with the rotation of the shaft 62. In this embodiment, in particular, the first support 21 and the second support 22 move with the rotation of the shaft 62.

With this configuration, the first distance d1 and the second distance d2 can be adjusted while being linked to each other. This makes it possible to easily and accurately change the first distance d1 and the second distance d2 depending on the frequency at which the conductivity is measured and the required measurement accuracy of the Q value.

As described above, the screw 620 shown in FIG. 1 has a first portion 621 and a second portion 622. The first portion 621 is a portion that moves the first support 21 by the rotation of the shaft 62, and the second portion 622 is a portion that moves the second support 22 by the rotation of the shaft 62. The direction of thread advancement of the first portion 621 and the direction of thread advancement of the second portion 622 are opposite to each other.

With this configuration, when the shaft 62 is rotated, the first support 21 and the second support 22 move closer to each other and farther away from each other. In other words, the distance can be easily adjusted while maintaining the relationship that the first distance d1 and the second distance d2 are equal to each other. This makes it easier to change the frequency at which the conductivity is measured. Also, since the number of rotations of the shaft 62 corresponds to the amount of change in the distance, the change operation is easy from that perspective as well.

In order to maintain the above relationship, the thread pitches of the first part 621 and the second part 622 should be equal. Having equal thread pitches is a concept that allows for deviations on the order of manufacturing errors.

As described above, the distance change unit 6 shown in FIG. 1 includes a rail 64, a first slider 65, and a second slider 66. The rail 64 extends parallel to a straight line passing through both the first conductor sample 91 and the second conductor sample 92. In other words, the rail 64 in FIG. 1 extends parallel to the Z-axis. The first slider 65 and the second slider 66 are configured to move along the rail 64. Two of the first support 21, the second support 22, and the third support 23 are connected to the first slider 65 and the second slider 66. In this embodiment, in particular, the first support 21 is connected to the first slider 65, and the second support 22 is connected to the second slider 66.

With this configuration, the first support 21 and the second support 22 can be moved with precision by moving the first slider 65 and the second slider 66 along the rail 64. This makes it possible to adjust the first distance d1 and the second distance d2 particularly easily and with high precision.

The disk resonator 1 shown in FIG. 1 has a first through hole 216 that penetrates the first support 21. The first through hole 216 extends parallel to a straight line that passes through both the first conductor sample 91 and the second conductor sample 92. The signal transmitting/receiving unit 5 includes a first through excitation wire 51 that is inserted into the first through hole 216.

According to such a configuration, unlike a configuration in which an excitation line is inserted between the first conductor sample 91 and the second conductor sample 92, for example, the distance between the first conductor sample 91 and the second conductor sample 92 can be freely set. In other words, the thickness of the excitation line does not affect the distance of the gap. Therefore, according to the disk resonator 1 shown in FIG. 1, the first through excitation line 51, which has a sufficient thickness and has low transmission loss, can be used. In addition, since electromagnetic waves are transmitted and received near the center of the third conductor sample 93 in a planar view, it is possible to selectively excite and detect a specific mode, such as the TM0n0 (n is an integer) mode, and high-order modes can be used for measurement with less influence of unnecessary modes. As a result, the conductivity can be accurately measured over a wider frequency range.

The disk resonator 1 shown in FIG. 1 has a second through hole 226 that penetrates the second support 22. The second through hole 226 extends parallel to a straight line that passes through both the first conductor sample 91 and the second conductor sample 92. The signal transmitting/receiving unit 5 has a second through excitation wire 52 that is inserted into the second through hole 226.

According to such a configuration, unlike a configuration in which an excitation line is inserted between the first conductor sample 91 and the second conductor sample 92, for example, the distance between the first conductor sample 91 and the second conductor sample 92 can be freely set. In other words, the thickness of the excitation line does not affect the distance of the gap. Therefore, according to the disk resonator 1 shown in FIG. 1, the second through excitation line 52, which has a sufficient thickness and has low transmission loss, can be used. In addition, since electromagnetic waves are transmitted and received near the center of the third conductor sample 93 in a plan view, it is possible to selectively excite and detect a specific mode, such as the TM0n0 (n is an integer) mode, and high-order modes can be used for measurement with less influence of unnecessary modes. As a result, the conductivity can be accurately measured over a wider frequency range.

In the disk resonator 1 shown in FIG. 1, the first distance d1 and the second distance d2 are changed by moving the first slider 65 and the second slider 66 along the rail 64. At this time, the distance change unit 6 can change the distance while maintaining the attitude of the second conductor sample 92 relative to the first conductor sample 91. This allows the symmetry of the structure to be maintained in the disk resonator 1 even if the first distance d1 and the second distance d2 are changed. As a result, the effect of the change in structure on the resonance mode can be reduced, and measurements with high reproducibility can be performed. This allows the conductivity to be measured accurately even if the first distance d1 and the second distance d2 are changed.

Note that maintaining the orientation of the second conductor sample 92 relative to the first conductor sample 91 means, for example, maintaining the first conductor sample 91 and the second conductor sample 92 in a parallel state to each other.

1.5 Measurement Procedure Next, a procedure for measuring the electrical conductivity using the disk resonator 1 will be described.

Figures 7 and 8 are cross-sectional views each illustrating the procedure for measuring electrical conductivity using the disk resonator 1.

First, after attaching the conductor samples 91, 92, and 93 to the disk resonator 1, the first slider 65 and the second slider 66 are moved to a position where the first conductor sample 91 and the third conductor sample 93 are in contact or close to each other, and the second conductor sample 92 and the third conductor sample 93 are in contact or close to each other, as shown in FIG. 7. At this point, the first distance d1 and the second distance d2 are each approximately zero, and the setting of the zero point is completed. For example, if the first distance d1 is not zero, the first distance d1 can be fine-tuned by shifting the position of the first fixing plate 214 relative to the first slider 65, etc.

The disk resonator 1 shown in Figures 7 and 8 further includes a distance measuring device 71 that measures the distance between the wall portion 614 and the first support 21, and a distance measuring device 72 that measures the distance between the wall portion 616 and the second support 22. These distance measuring devices 71, 72 measure distances using light L as a measurement probe. By including such distance measuring devices 71, 72, the distance between the wall portion 614 and the first support 21 and the distance between the wall portion 616 and the second support 22 can be known more accurately. This allows the first distance d1 and the second distance d2 to be adjusted more accurately. Note that the measurement principle of the distance measuring devices 71, 72 is not limited to this.

When the handle 63 is turned from the state shown in FIG. 7, the first support 21 and the second support 22 move away from each other as shown in FIG. 8. At this time, distance measuring devices 71, 72 may be used to monitor the changes in the first distance d1 and the second distance d2. Then, when the first distance d1 and the second distance d2 reach the target distance, the movement is stopped. After that, a signal is sent to the disk resonator 1, and the conductivity is calculated by analyzing the received signal.

2. Second Embodiment Next, a disk resonator according to a second embodiment will be described.
FIG. 9 is a cross-sectional view showing a disk resonator according to the second embodiment.

The second embodiment will be described below, focusing on the differences from the first embodiment and omitting explanations of similar points. Note that in each figure, the same reference numerals are used to designate the same components as in the first embodiment.

The disk resonator 1D shown in Figure 9 is similar to the disk resonator 1 shown in Figure 1, except that the configuration of the distance change section is different.

The distance change unit 6 shown in FIG. 1 has a shaft 62 with a screw 620 on the side. The screw 620 shown in FIG. 1 has a first part 621 and a second part 622 that move in opposite directions.

In contrast, the screw 620 of the distance changer 6D shown in FIG. 9 has a third part 623 and a fourth part 624 that have the same direction of advance but different pitches. Specifically, the third part 623 is screwed into the through hole 662 of the second slider 66, and is a part that moves the second support 22 by the rotation of the shaft 62. The fourth part 624 is screwed into the through hole 652D of the first slider 65, and is a part that moves the third support 23 by the rotation of the shaft 62. In this embodiment, the third support 23 is connected to the first slider 65, and the first support 21 is connected to the base 67. In this embodiment, the direction of advance of the screw of the third part 623 and the direction of advance of the screw of the fourth part 624 are the same. In addition, the pitch of the screw of the third part 623 is larger than the pitch of the screw of the fourth part 624. On the other hand, the insertion hole 672D of the base 67 is not threaded with the screw 620.

With this configuration, when the shaft 62 is rotated, the second support 22 approaches or moves away from the first support 21 by a larger amount than the third support 23. This makes it easy to adjust the distance while maintaining the relationship that the first distance d1 and the second distance d2 are equal to each other. As a result, the operation of measuring the Q value for various gap distances can be performed with higher reproducibility.

To maintain the above relationship more strictly, the thread pitch of the third portion 623 should be twice the thread pitch of the fourth portion 624. The concept of doubling the thread pitch is to allow for deviations on the order of manufacturing errors.

As described above, in the distance change unit 6D shown in FIG. 9, the second support 22 and the third support 23 move due to the rotation of the shaft 62.

With this configuration, the first distance d1 and the second distance d2 can be adjusted while being linked to each other. This makes it possible to easily and accurately change the first distance d1 and the second distance d2 depending on the frequency at which the conductivity is measured.

In addition, in the distance change unit 6D shown in FIG. 9, the second support 22 is connected to the second slider 66, and the third support 23 is connected to the first slider 65.

With this configuration, the second support 22 and the third support 23 can be moved with precision by moving the first slider 65 and the second slider 66 along the rail 64. This makes it possible to adjust the first distance d1 and the second distance d2 particularly easily and with high precision.

3. Third Embodiment Next, a disk resonator according to a third embodiment will be described.
FIG. 10 is a cross-sectional view showing a disk resonator according to the third embodiment.

The third embodiment will be described below, focusing on the differences from the first embodiment and omitting the description of similar points. Note that in each figure, the same components as those in the first embodiment are given the same reference numerals. Note that some components are not shown in FIG. 10.

The disk resonator 1E shown in FIG. 10 has a first support 21, a second support 22, a third support 23E, a signal transmitting/receiving unit (not shown), and a distance changing unit 6E.

The third support 23E shown in FIG. 10 has a hanging thread 236. The hanging thread 236 hangs down from above the third conductor sample 93, and the third conductor sample 93 is attached to its lower end.

The distance change unit 6E shown in FIG. 10 includes bolts 682, nuts 684, a third fixing plate 686, a micrometer head 687, and coil springs 688. The bolts 682 are fully threaded bolts that penetrate both the first fixing plate 214 and the second fixing plate 224. Nuts 684 are screwed into the ends of the bolts 682 on the negative side of the Z axis. Meanwhile, a third fixing plate 686 is screwed into the ends of the bolts 682 on the positive side of the Z axis. As a result, the first support 21 and the second support 22 are sandwiched between the nuts 684 and the third fixing plate 686. The bolts 682, 682 are not limited to the fully threaded bolts described above, but may be rod-shaped members with male threads on some parts, or may be any rod-shaped member that can be connected to the nuts 684, 684 or a member that replaces them, or the third fixing plate 686 by means other than screws.

The sleeve 243 of the micrometer head 687 is connected to the third fixed plate 686, and the spindle 244 is connected to the first fixed plate 214. This allows the distance of the first support 21 relative to the third fixed plate 686 to be fine-tuned by the micrometer head 687.

Bolts 682, 682 are inserted into the inside of the coil springs 688, 688. The coil springs 688, 688 are disposed between the first fixing plate 214 and the second fixing plate 224.

In such a distance change unit 6E, the force (pressing force) of the micrometer head 687 pressing the third fixed plate 686 toward the negative Z-axis side is balanced with the restoring force of the coil springs 688, 688. In other words, the coil springs 688, 688 generate a restoring force to press the first fixed plate 214 against the micrometer head 687 and to press the second fixed plate 224 against the nuts 684, 684. This makes it possible to uniquely determine the positions of the first support 21 and the second support 22 relative to the third fixed plate 686 by operating the micrometer head 687. In other words, the distance change unit 6E makes it possible to easily adjust the separation distance between the first conductive sample 91 and the second conductive sample 92 with high precision.

Therefore, when measuring the conductivity, first, the position of the entire structure including the first support 21, the second support 22, and the distance changer 6E is adjusted relative to the position of the third support 23E. Specifically, the third conductor sample 93 suspended by the hanging thread 236 is positioned at the midpoint between the first conductor sample 91 and the second conductor sample 92. At this time, the first distance d1 can be changed by the distance changer 6E.

As described above, the third support 23E according to this embodiment is structurally independent from the first support 21 and the second support 22. The distance change unit is configured to change at least one of the first support 21 and the second support 22 by moving at least one of the first support 21 and the second support 22 and changing the separation distance between the first support 21 and the second support 22, thereby changing at least one of the first distance d1 and the second distance d2. As an example, the distance change unit 6E according to this embodiment changes the first distance d1 by moving the first support 21 relative to the second support 22.

According to this configuration, the first support 21 and the second support 22 are structurally independent from the third support 23E, so that the structure of the disk resonator 1E becomes simpler. Therefore, the manufacturing cost of the disk resonator 1E can be reduced. Also, according to this configuration, the distance between the first conductor sample 91 and the second conductor sample 92 and the distance between the first conductor sample 91 and the third conductor sample 93 are adjusted by the micrometer head 687, respectively, and are determined by the movement amount of the first support 21, that is, the distance of the first support 21 to the third fixing plate 686. Therefore, according to this embodiment, the distance measuring device 71 can be omitted.
In the third embodiment as described above, the same effects as in the first embodiment can be obtained.

The coil spring 688 can be replaced with any elastic material, such as rubber, elastomer, or a spring other than a coil spring. The hanging thread 236 can also be replaced with any holding material capable of holding the third conductor sample 93.

4. Fourth Embodiment Next, a disk resonator according to a fourth embodiment will be described.
FIG. 11 is a cross-sectional view showing a disk resonator according to the fourth embodiment.

The fourth embodiment will be described below, focusing on the differences from the second embodiment and omitting the description of similar points. Note that in each figure, the same components as those in the second embodiment are given the same reference numerals. Note that some components are not shown in FIG. 11.

The disk resonator 1F shown in FIG. 11 has a first support 21, a second support 22, a third support 23F, a signal transmitting/receiving unit (not shown), and a distance changing unit 6E.

The third support 23F shown in FIG. 11 has a third-a member 237a and a third-b member 237b that are equal in thickness. The third-a member 237a is disposed between the first conductor sample 91 and the third conductor sample 93, and has a gap 238a that penetrates in the Z-axis direction. The third-b member 237b is disposed between the second conductor sample 92 and the third conductor sample 93, and has a gap 238b that penetrates in the Z-axis direction.

In other words, the third support 23F is configured such that the third a member 237a, the third conductor sample 93, and the third b member 237b are stacked in this order and sandwiched between the first support 21 and the second support 22, thereby supporting the third conductor sample 93.

When the third conductor sample 93 is supported by the third support 23F, the gap 238a of the third-a member 237a is located between the first conductor sample 91 and the third conductor sample 93. The gap 238b of the third-b member 237b is located between the second conductor sample 92 and the third conductor sample 93.

According to this configuration, the thickness of the gap 238a and the thickness of the gap 238b can be made equal by the third a member 237a and the third b member 237b, which have the same thickness. In other words, gaps of equal thickness can be provided between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93. This makes it unnecessary to use the stand 61, the shaft 62, the rails 64, etc., of the first embodiment, and further simplifies the structure of the disk resonator 1F.
In the fourth embodiment as described above, the same effects as in the first and second embodiments can be obtained.

5. Fifth Embodiment Next, a disk resonator according to a fifth embodiment will be described.
FIG. 12 is a cross-sectional view showing a disk resonator according to the fifth embodiment.

The fifth embodiment will be described below. In the following description, the differences from the second embodiment will be mainly described, and the description of similar matters will be omitted. In each figure, the same components as those in the second embodiment are given the same reference numerals. In FIG. 12, some components are not shown.

The disk resonator 1G shown in FIG. 12 has a first support 21, a second support 22, a third support 23E, a signal transmitting/receiving unit 5G, and a distance changing unit 6E.

The signal transmitting/receiving unit 5G shown in FIG. 12 has a lateral excitation line 51G and a lateral excitation line 52G.

The lateral excitation line 51G is inserted between the first conductor sample 91 and the third conductor sample 93. The lateral excitation line 51G is inserted in a direction intersecting a straight line passing through both the first conductor sample 91 and the second conductor sample 92. In FIG. 12, as an example, the lateral excitation line 51G is inserted from the positive side of the Y axis toward the negative side of the Y axis.

The lateral excitation line 52G is inserted between the second conductor sample 92 and the third conductor sample 93. The lateral excitation line 52G is also inserted from a direction intersecting the straight line described above. In FIG. 12, as an example, the lateral excitation line 52G is inserted from the negative side of the Y axis toward the positive side of the Y axis.

With this configuration, there is no need to provide the holders 53 and 54 shown in FIG. 1, and therefore the structure of the signal transmitting/receiving unit 5G is simplified. In addition, with the signal transmitting/receiving unit 5G, by using the lateral excitation lines 51G and 52G, there is no need to provide through holes in the first conductor sample 91 and the second conductor sample 92. This makes it easier to prepare the first conductor sample 91 and the second conductor sample 92, and can further improve the efficiency of the measurement work.

In the fifth embodiment as described above, the same effects as in the first and second embodiments can be obtained. Note that the positions of the lateral excitation lines 51G and 52G in the Z-axis direction are not limited to the above positions, and may be anywhere between the first conductor sample 91 and the second conductor sample 92. Also, one of the lateral excitation lines 51G and 52G may be omitted. In other words, one of the lateral excitation lines 51G and 52G may be responsible for transmitting and receiving signals.

6. Sixth Embodiment Next, a conductivity measuring device according to a sixth embodiment will be described.
FIG. 13 is a diagram showing a conductivity measuring device according to the sixth embodiment.

The conductivity measuring device 10 shown in FIG. 13 includes the disk resonator 1 described above. Specifically, the conductivity measuring device 10 shown in FIG. 13 includes the disk resonator 1, a network analyzer 11, and a personal computer 12. The network analyzer 11 and the disk resonator 1 are connected via a transmission cable 13 and a reception cable 14.

The network analyzer 11 transmits electromagnetic waves to the disk resonator 1 and digitally processes the electromagnetic waves received from the disk resonator 1 to obtain analysis data such as the resonance frequency, insertion loss, and half-power width. The network analyzer 11 then outputs this analysis data to the personal computer 12.

The personal computer 12 calculates the conductivity of the conductor sample based on these analysis data, the initial conditions for the sample, the initial conditions for the disk resonator 1, and environmental conditions such as temperature and humidity.

Since this type of conductivity measuring device 10 is equipped with the aforementioned disk resonator 1, it is possible to efficiently measure the conductivity of a conductive sample in the high frequency range.

7. Seventh Embodiment Next, a conductivity measuring method according to a seventh embodiment will be described.
FIG. 14 is a flowchart showing a conductivity measuring method according to the seventh embodiment.

The conductivity measurement method shown in FIG. 14 is, for example, a method of measuring the conductivity of a first conductor sample 91, a second conductor sample 92, and a third conductor sample 93 by a balanced disk resonator method using the above-mentioned disk resonator 1. Specifically, the conductivity measurement method shown in FIG. 14 includes a sample placement step S102, a measurement step S104, and a calculation step S106.

In the sample placement step S102, the first conductor sample 91, the second conductor sample 92, and the third conductor sample 93 are placed so that there is a gap between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93. This results in the disk resonator 1.

In the measurement step S104, a signal is transmitted to the disk resonator 1 and a signal is received from the disk resonator 1. Specifically, in the measurement step S104, a signal is transmitted from the signal transmitting/receiving unit 5 to the first conductor sample 91, the second conductor sample 92, and the third conductor sample 93, and the signals from the first conductor sample 91, the second conductor sample 92, and the third conductor sample 93 are received by the signal transmitting/receiving unit 5.
In the calculation step S106, the received signal is analyzed to calculate the conductivity.

This method of measuring conductivity allows the conductivity of a conductor sample to be determined in at least one measurement operation. This method therefore allows efficient measurement of conductivity in the high frequency range.

In addition, because a gap is provided between the first conductor sample 91 and the third conductor sample 93, and between the second conductor sample 92 and the third conductor sample 93, there is no need to fill the gaps with a dielectric. This allows the number of components in the disk resonator 1 to be reduced, improving the efficiency of the measurement work.

Furthermore, by providing a gap, the conductive sample is not damaged or deformed, such as by denting, due to contact with the dielectric. This allows for more accurate measurement of the conductivity of the conductive sample, including the effects of the skin effect.

In the measurement step S104, the signal transmitted to the disk resonator 1 is, for example, a high-frequency signal equivalent to a microwave or millimeter wave. Specifically, the signal is preferably a high-frequency signal with a frequency of 300 MHz or more, more preferably a high-frequency signal with a frequency of 1 GHz or more, and even more preferably a high-frequency signal with a frequency of 10 GHz or more. The conductivity measurement method according to this embodiment is useful in that it can efficiently measure conductivity in such a high-frequency range.

The upper limit of the frequency of the signal transmitted to the disk resonator 1 is not particularly limited, but is set to approximately 300 GHz as an example. If this is exceeded, there is a risk that the accuracy of the conductivity measurement will decrease.

The above describes the disc resonator, conductivity measuring device, and conductivity measuring method of the present invention based on the illustrated embodiments, but the present invention is not limited to these.

For example, the disk resonator and conductivity measuring device of the present invention may be configured such that the parts of the above-mentioned embodiment and each of the above-mentioned configuration examples are replaced with any configuration having a similar function, or any configuration may be added to the above-mentioned embodiment and each of the above-mentioned configuration examples. Furthermore, the disk resonator of the present invention may be configured by combining at least two or more of the above-mentioned embodiments and each of the above-mentioned configuration examples.

The conductivity measurement method of the present invention may also include any additional steps for any purpose added to the above-described embodiment.

1 Disk resonator 1D Disk resonator 1E Disk resonator 1F Disk resonator 1G Disk resonator 5 Signal transmission/reception unit 5G Signal transmission/reception unit 6 Distance change unit 6D Distance change unit 6E Distance change unit 10 Conductivity measuring device 11 Network analyzer 12 Personal computer 13 Transmission cable 14 Reception cable 21 First support 22 Second support 23 Third support 23A Third support 23B Third support 23C Third support 23E Third support 23F Third support 51 First through excitation wire 51G Side excitation wire 52 Second through excitation wire 52G Side excitation wire 53 Holder 54 Holder 55 Transmission antenna 56 Reception antenna 61 Stand 62 Shaft 63 Handle 64 Rail 65 First slider 66 Second slider 67 Base 71 Distance measuring device 72 Distance measuring device 91 First conductor sample 92 Second conductor sample 93 Third conductive sample 212 First supporting conductor plate 214 First fixing plate 216 First through hole 222 Second supporting conductor plate 224 Second fixing plate 226 Second through hole 232 First frame 234 Dielectric member 234C Dielectric member 235 Through hole 236 Suspension string 237a Third a member 237b Third b member 238 Second frame 238a Cavity 238b Cavity 242X Micrometer head 242Y Micrometer head 243 Sleeve 244 Spindle 246X Coil spring 246Y Coil spring 532 Through hole 542 Through hole 612 Base 614 Wall portion 615 Insertion hole 616 Wall portion 617 Insertion hole 620 Screw 621 First portion 622 Second portion 623 Third portion 624 Fourth portion 652 Insertion hole 652D Insertion hole 662 Insertion hole 672 Insertion hole 672D Insertion hole 682 Bolt 684 Nut 686 Third fixing plate 687 Micrometer head 688 Coil spring AX1 First axis AX2 Second axis AX3 Rotation axis L Light P Plot mark S102 Sample placement step S104 Measurement step S106 Calculation step d1 First distance d2 Second distance

Claims (17)

a first support for supporting a first conductor sample;
a second support provided opposite to the first support and configured to support a second conductor sample;
a third support that supports the third conductor sample such that a gap filled with outside air is formed between the first conductor sample and the third conductor sample, and between the second conductor sample and the third conductor sample, respectively;
a signal transmitting/receiving unit configured to transmit and receive signals to and from the first conductor sample, the second conductor sample, and the third conductor sample;
A disk resonator comprising: The disk resonator according to claim 1, which has a distance changer that changes the first distance d1 between the first conductor sample and the third conductor sample, and the second distance d2 between the second conductor sample and the third conductor sample. The distance change unit is
a shaft having a screw on a side surface thereof and rotating about an axis of rotation;
a stand that rotatably supports the shaft;
Equipped with
3. The disk resonator according to claim 2, wherein any two of the first support, the second support and the third support move with rotation of the shaft. the screw has a first portion that moves the first support and a second portion that moves the second support;
4. The disk resonator according to claim 3, wherein the threads of said first portion and said second portion have opposite thread directions. the screw has a third portion that moves the second support and a fourth portion that moves the third support;
a thread advance direction of the third portion and a thread advance direction of the fourth portion are the same as each other,
4. The disc resonator of claim 3, wherein the pitch of the threads of said third portion is greater than the pitch of the threads of said fourth portion. The distance change unit is
a rail extending parallel to a straight line passing through both the first conductor sample and the second conductor sample;
a first slider and a second slider that move along the rail;
Equipped with
3. The disk resonator according to claim 2, wherein two of the first support, the second support and the third support are connected to the first slider and the second slider. a first through hole extending parallel to a straight line passing through both the first conductor sample and the second conductor sample and penetrating the first support;
The disk resonator according to claim 1 , wherein the signal transmitting/receiving portion includes a first through-hole excitation line inserted into the first through-hole. a second through hole extending parallel to the straight line and penetrating the second support;
The disk resonator according to claim 7 , wherein the signal transmitting/receiving unit includes a second through-hole excitation line inserted into the second through-hole. The disk resonator according to any one of claims 1 to 6, wherein the signal transmitting/receiving unit includes a lateral excitation line that is inserted between the first conductor sample and the second conductor sample from a direction that intersects with a straight line that passes through both the first conductor sample and the second conductor sample. The third support is
A first frame having a frame shape;
a dielectric member provided inside the first frame and connecting the first frame and the third conductor sample;
10. The disk resonator according to claim 1 , comprising: The third support is
a second frame provided outside the first frame;
a position adjustment unit that adjusts a position of the first frame relative to the second frame;
The disk resonator of claim 10 comprising: the third support is structurally independent from the first support and the second support;
3. The disk resonator according to claim 2, wherein the distance change unit changes at least one of the first distance d1 and the second distance d2 by moving at least one of the first support and the second support to change the separation distance between the first support and the second support. The disk resonator according to claim 2, 6 or 12, wherein the distance change unit changes the first distance d1 and the second distance d2 while maintaining the orientation of the second conductor sample relative to the first conductor sample. the third support has a third a member and a third b member each having a through gap and having an equal thickness, the third a member, the third conductor sample and the third b member being stacked in this order and sandwiched between the first support and the second support, thereby supporting the third conductor sample;
When the third conductor sample is supported by the third support,
the gap portion of the third a member is located between the first conductive sample and the third conductive sample,
The disk resonator according to claim 2 , wherein the gap provided in the third b member is located between the second conductive sample and the third conductive sample. A conductivity measuring device comprising a disk resonator according to any one of claims 1 to 14. A conductivity measuring method for measuring the conductivity of a first conductor sample, a second conductor sample, and a third conductor sample by a balanced disk resonator method, comprising:
a sample arrangement step of arranging the first conductive sample, the second conductive sample, and the third conductive sample such that gaps filled with outside air are formed between the first conductive sample and the third conductive sample, and between the second conductive sample and the third conductive sample, respectively;
a measuring step of transmitting signals to the first conductor sample, the second conductor sample, and the third conductor sample, and receiving signals from the first conductor sample, the second conductor sample, and the third conductor sample;
A calculation step of analyzing the received signal and calculating the conductivity;
A method for measuring electrical conductivity comprising the steps of: The conductivity measurement method according to claim 16, wherein the signal to be transmitted is a high-frequency signal having a frequency of 300 MHz or more.

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