JP4428232B2 - Dielectric constant measuring apparatus and dielectric constant measuring method using the same - Google Patents

Description

  The present invention relates to a dielectric constant measuring apparatus and a dielectric constant measuring method using the same.

  In an electronic device in which electronic components such as a high-frequency circuit and a high-speed operation circuit are incorporated, it is common to use a high frequency band from several hundred MHz to several GHz.

  In developing electronic components that operate stably in such a high frequency band, it is necessary to measure and evaluate the dielectric constant of dielectrics used in electronic components, such as thermosetting resin materials and ceramic materials. is there. A perturbation method is known as one method for measuring the dielectric constant of a dielectric.

  In the perturbation method, the dielectric to be measured for dielectric constant is inserted into the cavity resonator, the resonance characteristics in the cavity resonator are measured before and after insertion, and the dielectric constant of the dielectric is measured from this change. It is. As a dielectric constant measurement method using such a perturbation method, for example, a dielectric constant measurement method described in Patent Document 1 is known.

The cavity resonator used in the invention described in Patent Document 1 has a cylindrical main body and two flat side walls provided on both ends of the main body, respectively, and two flat side walls. A sample insertion opening is formed in one of the side walls. A dielectric material processed into a rod shape is inserted from the sample insertion port, and the dielectric properties of the dielectric material are measured by measuring the resonance characteristics in the cavity resonator before and after the insertion.
JP-A-9-3111151

  However, in the method for measuring the dielectric constant of the dielectric described in Patent Document 1 described above, it is necessary to process the dielectric into a rod shape in order to insert the dielectric from the sample insertion port. For this reason, the dielectric constant cannot be measured for dielectrics that are difficult to be molded into a predetermined shape, such as dielectrics that are difficult to process, such as extremely hard materials. The target that can be done was extremely restricted.

  Further, the measured dielectric constant value was the average dielectric constant of the entire dielectric mounted on the measuring apparatus. Therefore, the local dielectric constant of the sample cannot be measured, and the distribution of the dielectric constant in the sample cannot be examined.

  This invention is made | formed in view of the said situation, and it aims at providing the dielectric constant measuring apparatus which can measure a local dielectric constant about the sample of various shapes, and a dielectric constant measuring method using the same. .

In order to solve the above problems, a dielectric constant measuring apparatus according to the present invention includes a cylindrical main body portion and a pair of side wall portions that are provided on both end sides of the main body portion and form a cavity together with the main body portion, A cavity resonator that is a sample placement portion in which one of the pair of sidewall portions has a through hole and a measurement sample is placed, and a columnar dielectric placed in the cavity of the cavity resonator. and a body, the sample placement part has a flat surface for positioning the measurement sample at a position opposed to the through hole a outside of the cavity resonator, the columnar dielectric end the through hole The insertion portion is inserted into the through hole, and the non-insertion portion is connected to the insertion portion and provided in the cavity, and the non-insertion portion is thicker than the insertion portion. Features.

  According to this dielectric constant measuring apparatus, when high frequency power is input into the cavity of the cavity resonator, a predetermined electromagnetic field mode is generated in the cavity. At this time, an evanescent electromagnetic field leaks out of the cavity resonator from the through hole of the sample placement portion. Then, a sample is arranged outside the cavity resonator at a position facing the through hole of the sample arrangement portion, and a resonance frequency and an unloaded Q value in the cavity resonator are obtained. Here, the resonance frequency and the no-load Q value change before and after the sample is arranged, and the dielectric constant of the sample can be calculated based on the amount of change. Therefore, the dielectric constant of the sample can be calculated by comparing the resonance frequency and the no-load Q value before and after the sample is arranged and obtaining the amount of change between them. Thus, according to the present invention, the dielectric constant of the sample can be measured even when the sample is disposed outside the cavity resonator. Therefore, the dielectric constant can be measured for samples having various shapes.

  Further, the evanescent electromagnetic field that leaks out of the cavity resonator from the through hole attenuates exponentially toward the outside of the cavity resonator. For this reason, the region where the evanescent electromagnetic field exists is limited to a narrow region near the through hole. Therefore, when a sample is placed in the sample placement portion, an evanescent electromagnetic field is incident on the local region in the sample, and the resonance frequency and no-load Q value measured at this time reflect the dielectric constant of the local region. Therefore, according to the dielectric constant measuring apparatus of the present invention, the local dielectric constant in the sample can be calculated, and the uniformity of the dielectric constant and the distribution of the dielectric constant value in the sample can be examined.

  Furthermore, the electric field in the cavity resonator is more concentrated in the dielectric than when there is no dielectric. Along with this, the intensity of the evanescent electromagnetic field leaking out of the cavity resonator also increases. For this reason, even if it is a sample with a small dielectric constant, a dielectric constant can be measured with high precision.

In the dielectric constant measuring apparatus, the columnar dielectric body includes an insertion portion that is inserted into the through hole, and a non-insertion portion that is connected to the insertion portion and provided in the cavity. It has thick than the insertion portion.

  In this case, since the non-insertion portion of the columnar dielectric is thicker than the insertion portion, deformation of the sample placement portion due to the weight of the sample is sufficiently suppressed. Therefore, changes in the resonance frequency and no-load Q value due to deformation of the sample placement portion can be sufficiently suppressed, and the dielectric constant measurement accuracy for the sample can be improved.

  In addition, the sample placement part is configured by a thin part including the through-hole and where the sample is placed, and a thick part surrounding the thin part and having a thickness larger than the thin part. preferable.

  The thinner the sample placement portion, the greater the strength of the evanescent electromagnetic field that leaks from the through hole. For this reason, when the sample placement part is composed of a thin part including a through hole and a thick part surrounding the specimen as described above, the resonance frequency is measured before and after placing the sample at a position facing the through hole. In addition, the amount of change in the no-load Q value increases. Therefore, the dielectric constant of a sample having a small dielectric constant can also be measured.

In addition, compared with a cavity resonator in which the entire sample placement part is thin, the thin part is limited to the thin part where the sample in the sample placement part is placed, so deformation due to insufficient mechanical strength of the sample placement part. The measurement error caused can be sufficiently reduced.

  Further, the columnar dielectric is composed of an insertion portion that is inserted into the through hole of the sample placement portion, and a non-insertion portion that is connected to the insertion portion and provided in the cavity, and the non-insertion portion is thicker than the insertion portion. The deformation of the thin portion of the sample placement portion due to the weight of the sample is sufficiently suppressed. Therefore, changes in the resonance frequency and no-load Q value due to deformation of the sample placement portion can be sufficiently suppressed, and the dielectric constant measurement accuracy for the sample can be improved.

In addition, the dielectric constant measuring apparatus of the present invention includes a cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion to form a cavity together with the main body portion. One of the side walls includes a cavity resonator that is a sample placement portion having a through-hole and on which a measurement sample is placed, and the sample placement portion is outside the cavity resonator and is located in the through-hole. A flat surface on which the measurement sample is arranged at an opposing position, a thin portion including the through-hole and where the sample is arranged, and a thick wall surrounding the thin portion and having a larger thickness than the thin portion It is comprised by the part.

  According to this dielectric constant measuring apparatus, when an electromagnetic field is generated in the cavity resonator, a predetermined electromagnetic field mode is generated in the cavity. At this time, an evanescent electromagnetic field leaks out of the cavity resonator from the through hole of the sample placement portion. Then, a sample is arranged outside the cavity resonator at a position facing the through hole of the sample arrangement portion, and a resonance frequency and an unloaded Q value in the cavity resonator are obtained. Here, the resonance frequency and the no-load Q value change before and after the sample is arranged, and the dielectric constant of the sample can be calculated based on the amount of change. Therefore, the dielectric constant of the sample can be calculated by comparing the resonance frequency and the no-load Q value before and after the sample is arranged and obtaining the amount of change between them. Thus, according to the present invention, the dielectric constant of the sample can be measured even when the sample is disposed outside the cavity resonator. Therefore, the dielectric constant can be measured for samples having various shapes.

  Further, the evanescent electromagnetic field that leaks out of the cavity resonator from the through hole attenuates exponentially toward the outside of the cavity resonator. For this reason, the region where the evanescent electromagnetic field exists is limited to a narrow region near the through hole. Therefore, when a sample is placed in the sample placement portion, an evanescent electromagnetic field is incident on the local region in the sample, and the resonance frequency and no-load Q value measured at this time reflect the dielectric constant of the local region. Therefore, according to the dielectric constant measuring apparatus of the present invention, the local dielectric constant in the sample can be calculated, and the uniformity of the dielectric constant and the distribution of the dielectric constant value in the sample can be examined.

  Furthermore, the thinner the sample placement portion, the greater the intensity of the evanescent electromagnetic field that leaks from the through hole. For this reason, when the sample placement part is composed of a thin part including a through hole and a thick part surrounding the specimen as described above, the resonance frequency is measured before and after placing the sample at a position facing the through hole. In addition, the amount of change in the no-load Q value increases. Therefore, the dielectric constant of a sample having a small dielectric constant can also be measured.

  In addition, compared with a cavity resonator in which the entire sample placement part is thin, the portion where the thickness is reduced is limited to the thin part where the sample is placed in the sample placement part, so the mechanical strength of the sample placement part is insufficient. The measurement error caused by the deflection due to can be sufficiently reduced.

The dielectric constant measurement method of the present invention includes a cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion and form a cavity together with the main body portion. An evanescent wave leaking step for leaking an evanescent wave from the through hole in the cavity resonator in which the one side wall portion has a through hole and the measurement sample is arranged, and in the cavity resonator, A first measurement step of measuring a resonance frequency and a no-load Q value; a sample placement step of placing a sample to be measured at a position outside the cavity resonator and facing the through hole; and Obtained in the second measurement step of measuring the resonance frequency and unloaded Q value in the cavity resonator, the first measurement step, and the second measurement step. From the measurement results, the dielectric constant of the sample Characterized in that it comprises a dielectric constant calculation step of leaving.

  According to the dielectric constant measurement method of the present invention, an evanescent electromagnetic field leaks out of the cavity resonator from the through hole of the sample placement portion. Then, a sample is arranged outside the cavity resonator at a position facing the through hole of the sample arrangement portion, and a resonance frequency and an unloaded Q value in the cavity resonator are obtained. Here, the resonance frequency and the no-load Q value change before and after the sample is arranged, and the dielectric constant of the sample can be calculated based on the amount of change. Therefore, the dielectric constant of the sample can be calculated by comparing the resonance frequency and the no-load Q value before and after the sample is arranged and obtaining the amount of change between them. Thus, according to the present invention, the dielectric constant of the sample can be measured even when the sample is disposed outside the cavity resonator. Therefore, the dielectric constant can be measured for samples having various shapes.

  Further, the evanescent electromagnetic field that leaks out of the cavity resonator from the through hole attenuates exponentially toward the outside of the cavity resonator. For this reason, the region where the evanescent electromagnetic field exists is limited to a narrow region near the through hole. Therefore, when a sample is placed in the sample placement portion, an evanescent electromagnetic field is incident on the local region in the sample, and the resonance frequency and no-load Q value measured at this time reflect the dielectric constant of the local region. Therefore, according to the dielectric constant measuring apparatus of the present invention, the local dielectric constant in the sample can be calculated, and the uniformity of the dielectric constant and the distribution of the dielectric constant value in the sample can be examined.

  ADVANTAGE OF THE INVENTION According to this invention, the dielectric constant measuring apparatus which can measure a local dielectric constant about the sample of various shapes, and the dielectric constant measuring method using the same are provided.

  Hereinafter, preferred embodiments of a dielectric constant measuring apparatus of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a perspective view showing a main configuration of a preferred embodiment of a dielectric constant measuring apparatus according to the present invention, and FIG. 2 is a longitudinal sectional view of the dielectric constant measuring apparatus shown in FIG.

  As shown in FIGS. 1 and 2, the dielectric constant measuring apparatus 10 includes a cylindrical cavity resonator 11 and a columnar dielectric 2. The cavity resonator 11 includes a cylindrical main body portion 3a and a pair of side wall portions 3b and 3c provided on both ends of the main body portion 3a. The main body portion 3a and the pair of side wall portions 3b and 3c A cavity 5 is formed. One side wall part 3 c of the pair of side wall parts 3 b and 3 c is a flat plate-like sample placement part 1 having a through hole 7, and the other side wall part 3 b is a bottom part of the cavity resonator 11. Yes.

  A columnar dielectric 2 is provided in the cavity 5. More specifically, the columnar dielectric 2 extends in the same direction as the extending direction of the cylindrical main body 3 a and is orthogonal to the sample placement portion 1. One end of the columnar dielectric 2 is inserted into the through hole 7 of the sample placement portion 1, and the other end of the columnar dielectric 2 is in contact with the surface of the bottom 3b of the main body 3a. The columnar dielectric 2 has a role of concentrating the electric field generated when high frequency power is input into the cavity 5 in the columnar dielectric 2.

The through-hole 7 is disposed at the center of the sample placement portion 1, and accordingly, the columnar dielectric 2 extends so as to pass through the central axis of the cylindrical main body 3 a. The reason why the through hole 7 is arranged in the central part of the sample arrangement part 1 is to measure the dielectric constant using the TM ₀₁₀ mode among various electromagnetic field modes generated in the cavity 5.

  The material used for the sample placement portion 1, the bottom portion 3b, and the main body portion 3a constituting the cavity resonator 11 is not particularly limited as long as it is made of a conductive material, but from the viewpoint of workability, mechanical strength, and the like. Metal is preferably used. Examples of such metals include silver, copper, aluminum, and brass.

  Examples of the dielectric material constituting the columnar dielectric 2 include inorganic oxide materials such as alumina, magnesia and zirconia, silicon-containing materials such as silicon carbide and silicon nitride, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyamide, polyester, Thermosetting resins such as thermoplastic resins such as polycarbonate, epoxy resins, acrylic resins, phenol resins, polyester resins, diallyl phthalate resins and the like can be mentioned. Among these dielectric materials, alumina is preferable from the viewpoints of workability and low dielectric loss.

  A more specific configuration of the dielectric constant measuring apparatus 10 will be described with reference to FIG. FIG. 3 is a schematic diagram showing the configuration of the dielectric constant measuring apparatus 10. As shown in FIG. 3, the dielectric constant measuring apparatus 10 includes a transmission loop antenna terminal 8 and a reception loop antenna 9 provided in the main body 3 a of the cavity resonator.

  The transmission loop antenna 8 is electrically connected to a high frequency power source 12 so that an electromagnetic field mode is formed in the cavity by a high frequency current input from the high frequency power source 12. The reception loop antenna 9 is electrically connected to the detection device 13 so as to receive the electric field generated in the cavity 5 and send it to the detection device 13. The detection device 13 obtains the relationship between the position of the resonance peak and the peak intensity corresponding to each mode in the cavity resonator, and is electrically connected to the arithmetic processing device 14. The calculation processing result in the calculation processing device 14, that is, the value of the dielectric constant of the sample can be displayed by the monitor device 15.

  Next, a method for measuring the dielectric constant of a sample using the dielectric constant measuring apparatus 10 will be described.

  In measuring the dielectric constant of the sample S, first, resonance characteristics generated in the cavity 5 are measured in a state where the sample S is not attached to the cavity resonator 11. For this purpose, high-frequency power is applied from the high-frequency power source 12 through the transmission loop antenna terminal 8 of the cavity resonator 11 to generate multimode resonance in the cavity 5 of the cavity resonator 11. Thereby, an evanescent wave is leaked from the through hole 7 (evanescent wave leaking step).

Then, the electric field generated in the cavity 5 is received through the reception loop antenna terminal 9 of the cavity resonator 11 and sent to the detection device 13. In the detection device 13, the relationship between the position of the resonance peak and the peak intensity corresponding to each mode is obtained. Therefore, to determine the resonance frequency _{f o} and the unloaded Q value _{Q o} the _{TM 010} mode when the specimen S is not mounted (first measurement step).

  Next, the sample S is placed outside the cavity resonator 11 at a position facing the through hole 7 on the sample placement portion 1 (sample placement step). Note that the sample S has a flat surface for stable placement on the sample placement portion 1.

Then, the resonance frequency f _s and the no-load Q value Q _s of the TM ₀₁₀ mode are determined in a state where the sample S is placed on the sample placement portion 1 of the cavity resonator 11 (second measurement step).

The dielectric constant of the sample S is calculated from the resonance frequency f _o , the no-load Q value Q _o , the resonance frequency f _s , and the no load Q value Q _s obtained by the above measurement (dielectric constant calculation step). Here, the resonance frequency and the no-load Q value change before and after the sample S is arranged, and the dielectric constant of the sample S can be calculated based on these changes. Therefore, the dielectric constant of the sample S can be calculated by comparing the resonance frequency and the no-load Q value before and after the sample S is arranged, and obtaining these changes. The calculation of the dielectric constant is performed by the arithmetic processing unit 14 based on the output data sent from the detection device 13, and the arithmetic processing result is displayed on the monitor device 15.

  Thus, according to the dielectric constant measuring apparatus 10, the dielectric constant of the sample S can be measured even when the sample S is arranged outside the cavity resonator 11. For this reason, it is not necessary to process the sample S into a special shape for insertion into the cavity resonator 11, and the dielectric constant can be measured even for a sample that is difficult to process. Therefore, according to the dielectric constant measuring apparatus 10, dielectric constant can be measured for samples having various shapes.

  Further, the evanescent electromagnetic field leaking outside the cavity resonator 11 from the through hole 7 is attenuated exponentially toward the outside of the cavity resonator 11. For this reason, the region where the evanescent electromagnetic field exists is limited to a narrow region near the through hole 7. Therefore, when the sample S is placed in the sample placement portion 1, an evanescent electromagnetic field is incident on the local region in the sample S, and the resonance frequency and unloaded Q value measured at this time reflect the dielectric constant of the local region. Therefore, according to the dielectric constant measuring apparatus 10, the local dielectric constant in the sample S can be calculated. Therefore, by moving the sample S on the sample placement unit 1 and measuring the dielectric constant of the sample S each time the sample S is moved, the uniformity of the dielectric constant and the distribution of the dielectric constant value in the sample S are examined. Can do.

  Furthermore, the electric field in the cavity resonator 11 is more concentrated in the dielectric 12 than when the columnar dielectric 12 is not provided. Accordingly, the intensity of the evanescent electromagnetic field that leaks out of the cavity resonator 11 also increases. For this reason, even if it is a sample with a small dielectric constant, a dielectric constant can be measured with high precision.

  Further, since the surface on which the sample is arranged in the sample placement portion 1 of the cavity resonator 11 is a flat surface, when the sample S is placed on the flat surface of the sample placement portion 1 and the dielectric constant is measured, The sample S can be stably placed. Therefore, the measurement error due to the sample S being placed in an unstable state can be suppressed sufficiently small.

(Second Embodiment)
Next, a second embodiment of the dielectric constant measuring apparatus according to the present invention will be described with reference to FIG.

  FIG. 4 is a sectional view showing a second embodiment of the dielectric constant measuring apparatus according to the present invention. As shown in FIG. 4, the dielectric constant measuring apparatus 20 of the present embodiment includes an insertion portion 2 a in which the columnar dielectric 2 is inserted into the through hole 7 of the sample placement portion 1, and the insertion portion 2 a connected to the cavity 5. It differs from the dielectric constant measuring apparatus 10 of 1st Embodiment by the point comprised by the non-insertion part 2b provided, and the non-insertion part 2b being thicker than the insertion part 2a.

  According to the dielectric constant measuring apparatus 20, since the non-insertion part 2b of the columnar dielectric 2 is thicker than the insertion part 2a, when the sample S is placed on the sample placement part 1, it depends on the weight of the sample S. Deformation of the sample placement unit 1 is sufficiently suppressed. Therefore, according to the dielectric constant measuring apparatus 20, the measurement error due to the deformation of the sample placement unit 1 can be sufficiently suppressed, and the dielectric constant measurement accuracy for the sample S can be improved.

(Third embodiment)
Next, a third embodiment of the dielectric constant measuring apparatus according to the present invention will be described with reference to FIG.

  FIG. 5 is a cross-sectional end view showing a third embodiment of the dielectric constant measuring apparatus according to the present invention. As shown in FIG. 5, the dielectric constant measuring apparatus 30 of the present embodiment is different from the dielectric constant measuring apparatus 20 of the second embodiment in that the sample placement unit 1 is configured as follows.

  That is, in the dielectric constant measuring apparatus 30 of the present embodiment, the sample placement unit 1 includes a thin part 1a on which the sample S is placed, and a thick part 1b that surrounds the thin part 1a and has a larger thickness than the thin part 1a. It consists of and. Here, the thin portion 1 a has a through hole 7.

  As described above, when the thin portion 1a is formed around the through hole 7 and the thin portion 1a is made thinner than the thick portion 1b surrounding the thin portion 1a, an evanescent electromagnetic field having high strength leaks from the through hole 7. come. For this reason, it is possible to increase the amount of change in the electromagnetic field mode in the cavity 5 that occurs when the sample S is placed from a state where it is not placed in the sample placement portion 1. Therefore, there is an advantage that the dielectric constant of the sample S can be measured with higher accuracy, and the dielectric constant can be measured with higher sensitivity even for a sample with a low dielectric constant.

  On the other hand, if a part of the sample placement part 1 is made thin by providing the thin part 1a in the sample placement part 1, the mechanical strength of the sample placement part 1 tends to decrease, and the sample placement part having an excessively thin part When the sample S is placed on the sample 1, the sample placement unit 1 is deformed by the weight of the sample S, and a measurement error may occur due to the deformation. Such a measurement error may occur particularly when a material having a low mechanical strength is used for the sample placement unit 1.

  In the dielectric constant measuring apparatus 30 of this embodiment, as shown in FIG. 5, the non-insertion part 2b of the columnar dielectric 2 is thicker than the insertion part 2a. For this reason, according to the dielectric constant measuring apparatus 30, even if the sample S is placed on the thin portion 1a, the deformation of the sample placement portion 1 due to the weight of the sample S is sufficiently suppressed.

  As described above, according to the dielectric constant measuring apparatus 30, it is possible to sufficiently reduce the thickness around the through hole 7 while sufficiently preventing deformation of the sample placement portion 1. For this reason, the measurement accuracy of the dielectric constant of the sample S can be improved.

(Fourth embodiment)
Next, a fourth embodiment of the dielectric constant measuring apparatus according to the present invention will be described with reference to FIG.

  FIG. 6 is a sectional end view showing a fourth embodiment of the dielectric constant measuring apparatus according to the present invention. As shown in FIG. 6, the dielectric constant measuring apparatus 40 of the present embodiment is different from the dielectric constant measuring apparatus 30 of the third embodiment in that it does not have the columnar dielectric 12.

  Even in the dielectric constant measuring apparatus 40, when the sample S is disposed outside the cavity resonator 11, the dielectric constant of the sample S can be measured. For this reason, it is not necessary to process the sample S into a special shape for insertion into the cavity resonator 11, and the dielectric constant can be measured even for a sample that is difficult to process. Therefore, according to the dielectric constant measuring apparatus 40, the dielectric constant can be measured for samples having various shapes.

  Further, the evanescent electromagnetic field leaking outside the cavity resonator 11 from the through hole 7 is attenuated exponentially toward the outside of the cavity resonator 11. For this reason, the region where the evanescent electromagnetic field exists is limited to a narrow region near the through hole 7. Therefore, when the sample S is placed in the sample placement portion 1, an evanescent electromagnetic field is incident on the local region in the sample S, and the resonance frequency and unloaded Q value measured at this time reflect the dielectric constant of the local region. Therefore, according to the dielectric constant measuring apparatus 10, the local dielectric constant in the sample S can be calculated. Therefore, by moving the sample S on the sample placement unit 1 and measuring the dielectric constant of the sample S each time the sample S is moved, the uniformity of the dielectric constant and the distribution of the dielectric constant value in the sample S are examined. Can do.

  In the dielectric constant measuring apparatus 40, it is preferable that the thin-walled portion 1a, which is a part of the sample placement portion 1, is made of a material (eg, copper) having sufficient mechanical strength. In this case, even if the weight of the sample S increases, the measurement error due to the deformation of the sample placement unit 1 can be suppressed sufficiently small, and the measurement accuracy can be improved.

  The present invention is not limited to the first to fourth embodiments. For example, in the dielectric constant measuring apparatus of the above-described embodiment, a cylindrical cavity resonator is used, which is based on the reason that the processing is easy. Therefore, the shape of the cavity resonator used in the dielectric constant measuring apparatus of the present invention is not necessarily limited to a cylindrical shape. For example, the shape of the cavity resonator used in the dielectric constant measuring apparatus of the present invention may be a cylinder having an elliptical or polygonal cross section.

In the above embodiment, the TM ₀₁₀ mode is used as the electromagnetic field mode in the cavity 5 in order to calculate the dielectric constant of the sample to be measured. However, the electromagnetic field mode used for calculating the dielectric constant is TM _010. The electromagnetic field mode other than the TM ₀₁₀ mode is not limited to the mode. In this case, it is preferable that the position of the through hole formed in the side wall portion of the cavity resonator is a position where the amplitude of the electric field mode or the magnetic field mode is maximized. Thus, a high-intensity evanescent electromagnetic field can be leaked from the through hole, and the dielectric constant of the sample can be measured.

It is a perspective view which shows the main structures in 1st Embodiment of the dielectric constant measuring apparatus which concerns on this invention. It is a longitudinal cross-sectional view of the dielectric constant measuring apparatus shown in FIG. It is the schematic which shows the specific structure of the dielectric constant measuring apparatus which concerns on this invention. It is sectional drawing which shows 2nd Embodiment of the dielectric constant measuring apparatus which concerns on this invention. It is a cut surface end view which shows 3rd Embodiment of the dielectric constant measuring apparatus which concerns on this invention. It is a cut surface end view which shows 4th Embodiment of the dielectric constant measuring apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sample arrangement | positioning part (side wall part), 1a ... Thin part, 1b ... Thick part, 2 ... Columnar dielectric, 2a ... Insertion part, 2b ... Non-insertion part, 3a ... Main part, 3b ... Bottom part (Side wall part) 5 ... cavity, 7 ... through hole, 10, 20, 30, 40 ... dielectric constant measuring device, 11, 33 ... cavity resonator, S ... sample.

Claims (5)

A cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion to form a cavity together with the main body portion, and one side wall portion of the pair of side wall portions has a through hole. A cavity resonator which is a sample placement portion on which a measurement sample is placed;
A columnar dielectric disposed in the cavity of the cavity resonator,
The sample placement portion has a flat surface on which the measurement sample is placed at a position outside the cavity resonator and facing the through hole,
The columnar dielectric has one end inserted into the through hole, is constituted by an insertion portion to be inserted into the through hole, the non-insertion portion that is coupled to said insertion portion provided in the cavity, the non The dielectric constant measuring apparatus, wherein the insertion portion is thicker than the insertion portion . The sample placement part, the thin-walled portion in which the sample comprises a through-hole is arranged, and a thick portion having a thickness greater than said thin portion surrounding said thin-walled portion, claim 1 The dielectric constant measuring apparatus according to 1. A cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion to form a cavity together with the main body portion, and one side wall portion of the pair of side wall portions has a through hole. A cavity resonator that is a sample placement portion on which a measurement sample is placed,
The sample placement portion has a flat surface on which the measurement sample is placed at a position outside the cavity resonator and facing the through-hole, and a thin-wall portion including the through-hole and where the sample is placed A dielectric constant measuring apparatus comprising: a thick part surrounding the thin part and having a thickness larger than that of the thin part. A cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion to form a cavity together with the main body portion, and one side wall portion of the pair of side wall portions has a through hole. An evanescent wave leaking step for leaking an evanescent wave from the through hole in the cavity resonator, which is a sample placement portion on which the measurement sample is placed;
A first measurement step of measuring a resonance frequency and an unloaded Q value in the cavity resonator;
A sample placement step of placing a sample to be measured at a position outside the cavity resonator and facing the through hole;
A second measurement step of measuring a resonance frequency and an unloaded Q value in the cavity resonator in a state where the sample is disposed at a position facing the through hole;
A dielectric constant calculation step of calculating a dielectric constant of the sample from the measurement results obtained in the first measurement step and the second measurement step ;
The sample placement section has a flat surface on which the measurement sample is placed at a position outside the cavity resonator and facing the through hole, and the cavity resonator is a columnar shape disposed in the cavity. The columnar dielectric is provided with a dielectric, and one end of the columnar dielectric is inserted into the through hole. The columnar dielectric is composed of an insertion portion that is inserted into the through hole and a non-insertion portion that is connected to the insertion portion and provided in the cavity. And the non-insertion part is thicker than the insertion part . A cylindrical main body portion and a pair of side wall portions that are provided on both ends of the main body portion to form a cavity together with the main body portion, and one side wall portion of the pair of side wall portions has a through hole. An evanescent wave leaking step for leaking an evanescent wave from the through hole in the cavity resonator, which is a sample placement portion on which the measurement sample is placed;
A first measurement step of measuring a resonance frequency and an unloaded Q value in the cavity resonator;
A sample placement step of placing a sample to be measured at a position outside the cavity resonator and facing the through hole;
A second measurement step of measuring a resonance frequency and an unloaded Q value in the cavity resonator in a state where the sample is disposed at a position facing the through hole;
A dielectric constant calculation step of calculating a dielectric constant of the sample from the measurement results obtained in the first measurement step and the second measurement step ;
The sample placement portion has a flat surface on which the measurement sample is placed at a position outside the cavity resonator and facing the through-hole, and a thin-wall portion including the through-hole and where the sample is placed A dielectric constant measuring method comprising: a thick part surrounding the thin part and having a thickness larger than that of the thin part .

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