JP2006275687A - Permittivity measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permittivity measuring method for obtaining permittivity precisely also to a sample in an arbitrary shape by combining a permittivity conversion curve created by using an electromagnetic field simulation with a purtervation method. <P>SOLUTION: In the permittivity measuring method, an electromagnetic field simulation is executed from each shape data of the sample 1 and a cavity resonator 2 and the waveform data of an input signal 3 to create the permittivity conversion curve in a step S1. When the sample 1 is inserted into and is not inserted into the cavity resonator 2, the input signal 3 is applied into the cavity resonator 2 for resonating, and each resonance frequency is measured. Then, the difference in the resonance frequency is measured depending on the presence/absence of the sample 1, thus calculating the permittivity of the sample 1 from the difference in the resonance frequency and the permittivity conversion curve. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a dielectric constant measuring method for measuring a dielectric constant of a dielectric material, and more particularly to a technical field of a dielectric constant measuring method capable of measuring a dielectric constant of a dielectric part in a product shape.

In recent years, electronic circuits using high frequency bands ranging from several hundred MHz to several GHz have been widely used, and accordingly, the characteristics of component materials used in electronic circuits are measured with higher accuracy. There is a growing demand to do so.

For example, a dielectric component for a GPS antenna is required to have a high dielectric constant and low loss, and a dielectric component having a relative dielectric constant of about 10 to 20 is widely used in other applications. Therefore, a technique that can measure the dielectric constant with higher accuracy is strongly desired.

As a conventional dielectric constant measurement method, a method defined in the JIS standard is often used as a representative method. This is a dielectric constant measurement method for a frequency band of about 1 to 2 GHz, and there are two types, a dielectric resonator method (JIS-R1627) and a cavity resonator method (JIS-R1641). As a target for a higher frequency band, a Fabry-Perot resonator method is known for a frequency band of about several tens of GHz.

In these dielectric constant measurement methods, the shape of the sample to be measured is limited to a parallel plate or a cylinder, so that the dielectric constant can be calculated based on an analytical expression. By using this analytical expression, a highly accurate dielectric constant of about four significant figures can be obtained.

In addition, as a dielectric constant measurement method different from the above, a perturbation method using a cavity resonator is also well known. In the perturbation method, the resonance frequency of the cavity resonator is measured with and without the sample in the cavity resonator, and the dielectric constant ε is calculated from the difference Δf between the two. When this measurement method is used, it is possible to measure the dielectric constant of a sample having an arbitrary shape.

However, in the conventional perturbation method, an approximate expression is used to calculate the dielectric constant ε from the measured Δf. For this reason, the problem is that the accuracy of the dielectric constant obtained from the approximate expression is as low as about 3%. When the relative dielectric constant is as low as about 1-2, ε and Δf are in a substantially linear relationship and can be approximated with relatively high accuracy. It was difficult to apply the perturbation method.

Non-Patent Document 1 discloses a method of measuring a dielectric constant with higher accuracy than before by using a perturbation method. In order to improve measurement accuracy, a network analyzer is used as a measuring instrument, and data at all points in the vicinity of the resonance peak is taken into the computer from the network analyzer, and data processing for increasing accuracy is performed.

In Non-Patent Document 2, a measurement chart representing the relationship between the resonance frequency and the dielectric constant is created by numerical calculation using the FDTD (Finite Difference Time Domain) method, and this can be used for actual measurement. .

In order to reduce the time required for numerical calculation, the number of samplings in the time domain is reduced and the GPOF (Generalized Pencil of Function) method is applied to calculate the resonance frequency with the same degree of accuracy as when the number of samplings is increased. I can do it.

“Measurement of dielectric material by high-precision perturbation method optimal for evaluation in quasi-microwave to microwave band”, Yasushi Iijima, Electronic Monthly, July 1998, p16-19. “Study on measurement of dielectric constant of plate-like dielectric using square cavity resonator by FDTD method”, Tomomi Abe et al., IEEJ Transactions, Vol. 118, No. 9, p1043-1048, 1998.

In the conventional dielectric constant measurement method defined in the JIS standard, the shape of the sample is limited to a simple shape such as a parallel plate or a cylinder. This is because the dielectric constant can be expressed by an analytical expression as described above, and can be calculated accurately using this.

On the other hand, many dielectric parts used in products generally have complicated shapes such as chamfered corners or holes. It is possible to make a parallel plate or cylinder sample with the same material as the dielectric part and measure the dielectric constant of the sample.

However, even if the same material is used, the physical property value is likely to change during processing of the dielectric part. Therefore, it is desirable to measure the dielectric constant of the dielectric part in the shape used for the product. In the JIS standard method, the dielectric constant of a dielectric part cannot be measured as it is in the shape of the product. Therefore, a technique of a dielectric constant measurement method that can realize this with high accuracy is strongly desired.

In the perturbation method of Non-Patent Document 1, there is a big problem that the measurement sample is limited to an elongated rod-shaped sample. Further, the error of the dielectric constant was 1% or less, which was not high enough accuracy. In Non-Patent Document 2, the calculated dielectric constant error is about 1 to 3%, and sufficient accuracy is not obtained.

Accordingly, the present invention provides a dielectric constant measurement method capable of obtaining a dielectric constant with high accuracy even for a sample of an arbitrary shape by combining a dielectric constant conversion curve created using a predetermined electromagnetic field simulation and a perturbation method. The purpose is to provide.

The first aspect of the dielectric constant measurement method according to the present invention assumes that at least two types of dielectric constants of the sample are assumed, and the sample having each dielectric constant is inserted into a predetermined cavity resonator and not inserted. The resonance frequency difference (hereinafter referred to as a numerical resonance frequency difference) is calculated using a predetermined electromagnetic field simulation, and the dielectric constant is calculated from the two or more types of dielectric constants and the calculated numerical resonance frequency differences. Create a rate conversion curve, measure the resonance frequency when the sample is inserted into the cavity resonator and not insert the sample, and determine the resonance frequency difference between them (hereinafter referred to as the resonance frequency difference by measurement), The dielectric constant measurement method is characterized in that the dielectric constant of the sample is calculated by comparing the resonance frequency difference obtained by the measurement with the dielectric constant conversion curve.

A second aspect is a dielectric constant measurement method, wherein the sample is placed at a position where the electric field energy accumulated in the space occupied by the sample is maximized inside the cavity resonator.

A third aspect is a dielectric constant measuring method, wherein an input terminal and an output terminal provided in the cavity resonator include a probe or a small hole having a length of 15 mm or less.

In a fourth aspect, the input terminal and the output terminal provided in the cavity resonator include a probe or an antenna having a length corresponding to 7.5% or less of the wavelength of resonance generated in the cavity resonator. This is a dielectric constant measuring method.

According to a fifth aspect, the predetermined electromagnetic field simulation is a means for dividing the electromagnetic field space into cells of a predetermined size, calculating Maxwell's equations based on the center difference of the cells, and calculating a resonance frequency, At least two types of cell dimensions are changed to execute the predetermined electromagnetic field simulation, and the cell size is set to 0 based on the size of the two or more types of cells and the resonance frequency obtained from each simulation. A dielectric constant measurement method characterized by estimating a resonance frequency at the time.

In a sixth aspect, the electromagnetic field is assumed by assuming two or more kinds of dielectric constants sandwiching a dielectric constant estimated from a dielectric material forming the sample, as the dielectric constant of the sample used for the predetermined electromagnetic field simulation. A dielectric constant measurement method characterized by performing a simulation.

A seventh aspect is a dielectric constant measurement method, wherein the dielectric constant conversion curve is created by a polynomial having the resonance frequency difference as a parameter.

As described above, according to the present invention, since it is possible to measure the dielectric constant of a dielectric part having an arbitrary shape, the measurement is performed by manufacturing a parallel plate or cylinder sample with the same material as in the past. There is no need to do it. For example, even if the sample shape is powder, it is possible to determine the dielectric constant of the powder by filling it in a container with a known dielectric constant or by hardening it with a resin with a known dielectric constant.

As described above, the dielectric constant measurement method of the present invention can be widely applied to the determination of pass / fail as a dielectric material from the raw material stage to the product stage of the product in which the value of the dielectric constant is important. This greatly contributes to improvement and reduction of manufacturing man-hours.

In addition, according to the present invention, the accuracy can be improved by an order of magnitude compared to the conventional perturbation method (1% or more) (on the order of 0.1%), so that the dielectric constant of an arbitrarily shaped dielectric component can be calculated with high accuracy. It is possible to obtain an excellent effect that it can be performed.

A dielectric constant measurement method according to a preferred embodiment of the present invention will be described in detail with reference to the drawings. In addition, about each component which has the same function, the same code | symbol is attached | subjected and shown for simplification of illustration and description.

In the dielectric constant measurement method of the present invention, a perturbation method using a cavity resonator is used as a basic means. However, in the conventional perturbation method, an approximate expression is used to calculate the dielectric constant from the resonance frequency measured using the cavity resonator, whereas in the dielectric constant measurement method of the present invention, a predetermined electromagnetic field simulation is performed. The dielectric constant conversion curve created based on the numerical calculation by is used for calculating the dielectric constant.

  FIG. 1 is a diagram for explaining the overall processing flow of the dielectric constant measurement method according to the embodiment of the present invention. In the dielectric constant measurement method according to the present embodiment, as in the conventional perturbation method, the input signal 3 is applied to the cavity resonator 2 when the sample 1 is not inserted into the cavity resonator 2 and when the sample 1 is inserted. To resonate and measure the respective resonance frequency.

Then, the change in the resonance frequency due to the sample 1 being inserted into the cavity resonator 2 is measured, and the dielectric constant of the material 1 is determined from the difference in the resonance frequency between when the sample 1 is not inserted into the cavity resonator 2 and when it is inserted. Ask for.

In this embodiment, first, calculation of electromagnetic field simulation is performed in step S1 based on the shape data of the sample 1 and the cavity resonator 2 and the waveform data of the input signal 3. The calculation of the electromagnetic field simulation is performed for two cases where the sample 1 is not inserted into the cavity resonator 2 and when it is inserted.

Then, a dielectric constant conversion curve is created from the electromagnetic field simulation result. The dielectric constant conversion curve is used to calculate the dielectric constant from the resonance frequency difference between the case where the sample 1 is not inserted into the cavity resonator 2 and the case where the sample 1 is inserted (resonance frequency difference by the above measurement). Is. Details of the processing in step S1 will be described later.

Next, in step S2 and step S3, the input signal 3 is input to the cavity resonator 2 to generate resonance, and the resonance frequency at that time is measured. In step S2, the input signal 3 is input to the cavity resonator 2 without inserting the sample 1 into the cavity resonator 2, and the resonance frequency at that time (hereinafter referred to as the resonance frequency when there is no sample) is measured with a network analyzer or the like. To do.

On the other hand, in step S3, with the sample 1 inserted into the cavity resonator 2, the resonance frequency (hereinafter referred to as the resonance frequency when the sample is present) is measured in the same manner as in step S2.

An example of the output signal measured from the cavity resonator 2 is shown in FIG. FIG. 2 shows the output signal with the horizontal axis representing frequency and the vertical axis representing field strength. In the figure, an output signal 11 is an output signal when resonating without inserting the sample 1 into the cavity resonator 2, and an output signal 12 is caused to resonate by inserting the sample 1 into the cavity resonator 2. Is an output signal.

The output signal 11 when the sample 1 is not inserted has a peak electric field intensity at the frequency 13, and this frequency 13 is determined as the resonance frequency at this time. Further, the output signal 12 when the sample 1 is inserted moves to the lower frequency side as a whole compared to the output signal 11.

The frequency 14 at which the electric field intensity reaches a peak appears at a position lower than the frequency 13, and a resonance frequency difference (resonance frequency difference by the above measurement) indicated by 17 occurs. The electric field strength also decreases by the electric field strength difference 18 from the peak value 15 of the output signal 11 to the peak value 16 of the output signal 12.

In step S4, a resonance frequency difference by the measurement, which is a difference between the resonance frequency without sample measured in step S2 and the resonance frequency with sample measured in step S3, is calculated. In the following, it is assumed that the resonance frequency difference by the measurement is represented by Δf.

In step S5, the dielectric constant of the sample 1 is calculated from the resonance frequency difference obtained by the measurement using the dielectric constant conversion curve created in step S1. An example of the dielectric constant conversion curve is shown in FIG. FIG. 3 shows a dielectric constant conversion curve 21 where the vertical axis is the resonance frequency difference and the horizontal axis is the relative dielectric constant.

In FIG. 3, when the resonance frequency difference is Δf calculated in step S4, the relative dielectric constant εr is obtained from the dielectric constant conversion curve 21. As described above, by using the dielectric constant conversion curve 21, it is possible to obtain the relative dielectric constant of the sample 1 from the resonance frequency difference by the measurement measured using the cavity resonator 2. The dielectric constant of Sample 1 is obtained by multiplying the relative dielectric constant εr obtained from the dielectric constant conversion curve 21 by the vacuum dielectric constant.

Next, a method for creating a dielectric constant conversion curve by electromagnetic field simulation in step S1 will be described in detail below with reference to FIG. FIG. 4 is a diagram for explaining the flow of processing for numerically calculating the spatial distribution and temporal change of the electromagnetic field in the resonator 2 using a predetermined electromagnetic field simulator.

As the predetermined electromagnetic field simulator, the FDTD method and perfect boundary approximation (PBA) are applied in this embodiment. However, the electromagnetic field simulator is not limited to this, and any electromagnetic field simulator can be used as long as it can accurately analyze the spatial distribution and temporal change of the electromagnetic field in the resonator.

The FDTD method is a method of dividing the electromagnetic field space into cells of a predetermined size and calculating the Maxwell equation based on the center difference of the cells. In addition, with respect to time changes, simulation calculation is performed for each predetermined time width.

If an uneven sample is handled only by the FDTD method, it is greatly affected by the cell size. Therefore, it is necessary to make the cell size as fine as possible. The most accurate solution can be obtained when the cell size is reduced to zero. However, it is actually impossible to set the cell size to zero.

Further, the perfect boundary approximation is an effective technique for handling a sample of an arbitrary shape, and by calculating and using an equivalent physical property value such as a dielectric constant for each cell, the cell size can be set relatively. This is a technique that can improve the accuracy even when rough.

In FIG. 4, first, in step S11, the shape data of the sample 1 and the cavity resonator 2 and the waveform data of the input signal 3 are input to the electromagnetic field simulator as simulation conditions.

In step S12, the resonance frequency when the sample 1 is not inserted into the cavity resonator 2 is calculated using the electromagnetic field simulator. At this time, an appropriate value is selected and used for the cell size used in the FDTD method. The cell size can be determined based on the dimensions of the cavity resonator 2 and the like.

In step S13, a predetermined value is assumed as the dielectric constant of the sample 1 and is set in the electromagnetic field simulator. Here, the predetermined value of the dielectric constant is smaller than the dielectric constant estimated from the dielectric material forming the sample 1 so that the dielectric constant can be accurately estimated from the measured resonance frequency difference by interpolation. It is preferable to include a large dielectric constant.

For example, when the relative dielectric constant is intended for measurement of 30 or less, 5, 10, 15, 20, 25, and 30 are selected as relative dielectric constants, and the relative dielectric constants are stored in the electromagnetic field simulator. Set up sequentially and run the simulation.

Next, in step S14, one of a plurality of preselected values is set as the cell size used in the calculation of the FDTD method. As the cell size, a plurality of values can be selected based on the size of the cavity resonator 2, and the selected cell sizes are sequentially set in the electromagnetic field simulator to execute a simulation calculation.

In step S15, the electromagnetic field simulator is executed using the simulation conditions input in step S11, the dielectric constant selected in step S13, and the cell size selected in step S14, and the resonance frequency at this time is calculated. .

In step S16, it is determined whether the simulation calculation has been completed for all of the plurality of cell sizes selected in step S14. If only a part of the plurality of cell sizes has finished the simulation calculation, the process returns to step S14 to select the remaining cell size values. On the other hand, if the simulation calculation has been completed for all of the plurality of cell sizes, the process proceeds to the next step S17.

In step S17, the true value of the resonance frequency is estimated based on the resonance frequencies for the plurality of cell sizes. That is, the true value of the resonance frequency can be estimated by obtaining the resonance frequency when the cell size is extrapolated to 0 from the plurality of cell sizes and the respective resonance frequencies.

For example, when three types of values are selected as the plurality of cell sizes, the resonance frequency can be expressed as a quadratic expression of the cell size. In the quadratic equation, the resonance frequency when 0 is substituted for the cell size can be estimated as a true value.

FIG. 5 shows an embodiment in which the true value of the resonance frequency is obtained by the above method for a plurality of dielectric constants. In the drawing, when the dielectric constant is ε1, 31 represents the resonance frequency expressed by a quadratic expression from the three types of cell sizes. At this time, the resonance frequency 31a when the cell size is 0 is estimated as a true value.

Similarly, the quadratic expressions when the dielectric constant is ε2 to ε6 are indicated by 32 to 36, respectively, and the resonance frequencies 32a to 36a when the cell size is set to 0 are the true values of the resonance frequencies for the respective dielectric constants. It is said.

When the resonance frequency for any one of the dielectric constants selected in step S13 is obtained up to step S17, it is determined in step S18 whether or not the estimation of the true value of the resonance frequency has been completed for all the dielectric constants. If there is a dielectric constant for which the true value of the resonance frequency has not been estimated, the process returns to step S13 and the above calculation process is repeated.

On the other hand, when the estimation of the true value of the resonance frequency is completed for all the dielectric constants selected in step S13, the dielectric constant conversion curve is created in step S19. The dielectric constant conversion curve shows the relationship between the resonant frequency difference and the relative dielectric constant, as shown in FIG.

In step S19, first, a resonance frequency difference is obtained by subtracting the resonance frequency in the absence of the sample calculated in step S12 from each resonance frequency for the plurality of dielectric constants calculated in step S17. A dielectric constant conversion curve 21 can be created by drawing the resonance frequency difference and the relative dielectric constant corresponding thereto on a graph as shown in FIG.

Alternatively, it is possible to use the polynomial as a relative dielectric constant calculation formula by fitting the resonance frequency difference and the relative dielectric constant corresponding thereto with a predetermined polynomial.

FIG. 6 shows a comparison with the measurement result of the conventional cavity resonator method (JIS-R1641) in order to confirm the accuracy of the dielectric constant conversion curve 21. In order to measure the dielectric constant with high accuracy even with the conventional JIS-R1641, a sample 1 having a predetermined parallel plate was used.

FIG. 6A is a view similar to FIG. 3, but the dielectric constant conversion curve 41 is obtained when the sample 1 is the predetermined parallel plate. FIG. 6B is an enlarged view of the portion 42 in FIG. In FIG. 6B, reference numeral 43 represents the resonance frequency difference measured by the conventional JIS-R1641 and the relative dielectric constant at that time. It has been confirmed that the measurement result of JIS-R1641 agrees with the dielectric constant conversion curve 41 with high accuracy.

As described above, according to the dielectric constant measurement method of the present invention, the dielectric constant conversion curve is created by numerical calculation using an electromagnetic field simulator having a predetermined accuracy, and the dielectric constant conversion curve is used. The dielectric constant of the arbitrarily shaped dielectric part can be calculated with high accuracy.

A method of measuring the resonance frequency using the cavity resonator 2 in the dielectric constant measurement method of the present invention will be described below with reference to FIG. FIG. 7A is a diagram illustrating a schematic configuration of the cavity resonator 2. The sample 1 is inserted into the cavity resonator 2, an input signal is input from the input terminal 51, and an output signal is extracted from the output terminal 52. The input terminal 51 and the output terminal 52 are connected to the network analyzer 55 by coaxial cables 53 and 54, and the output signal taken from the output terminal 52 is measured by the network analyzer 55.

In the dielectric constant measurement method of the present invention, the position where the sample 1 is inserted into the cavity resonator 2 is preferably a position in the cavity resonator 2 where the electric field energy in the space is maximized. In FIG. 7A, the outline of the electric field energy distribution is indicated by 58, and the electric field energy distribution viewed from above the cavity resonator 2 is schematically shown in FIG. 7B. .

In FIG. 7B, the position 59 shows the highest electric field strength, and it is most desirable that the sample 1 is inserted at the position 59. The higher the electric field energy at the position where the sample 1 is inserted, the greater the resonance frequency difference.

In the dielectric constant measurement method of the present invention, it is desirable that the dimensions of the antennas or probes 56 and 57 of the input terminal 51 and the output terminal 52 used for electromagnetic field coupling in the cavity resonator 2 be 15 mm or less. By setting the dimensions of the antennas or probes 56 and 57 to 15 mm or less, the cavity resonator 2 can be appropriately measured.

Furthermore, in the measurement of the cavity resonator 2 of 1.5 GHz or more, it is desirable that the dimensions of the antennas or probes 56 and 57 be 7.5% or less of the measurement wavelength.

The cavity resonator 2 used in the dielectric constant measurement method of the present invention can be of any shape. That is, the cavity resonator 2 may be either a sealed type (cuboid, cylinder, sphere, spheroid) or an open type (fabric bellows type, NRD type).

As described above, according to the dielectric constant measurement method of the present invention, by combining the perturbation method and the electromagnetic field simulation, the dielectric constant can be measured with high accuracy of about 0.1% even for a sample of an arbitrary shape. It becomes possible.

FIG. 1 is a diagram for explaining the overall processing flow of the dielectric constant measurement method according to the embodiment of the present invention. FIG. 2 is a diagram illustrating an example of an output signal measured from the cavity resonator 2. FIG. 3 is a diagram showing an example of a dielectric constant conversion curve created by the dielectric constant measurement method of the present invention. FIG. 4 is a diagram for explaining the flow of processing for creating a dielectric constant conversion curve using a predetermined electromagnetic field simulator. FIG. 5 is a diagram showing an embodiment when the resonance frequency is expressed by a quadratic expression from the simulation results of three types of cell sizes. FIG. 6 is a diagram comparing the dielectric constant conversion curve created by the dielectric constant measurement method of the present invention with the measurement result of the conventional cavity resonator method (JIS-R1641). FIG. 6A shows a dielectric constant conversion curve when the sample is a predetermined parallel plate. FIG. 6B is an enlarged view of the portion 42 in FIG. FIG. 7 is a diagram for explaining a resonance frequency measurement method using the cavity resonator 2 in the dielectric constant measurement method of the present invention. FIG. 7A illustrates a schematic configuration of the cavity resonator. FIG. 7B is a diagram schematically showing the distribution of the electric field energy as viewed from above the cavity resonator 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Sample 2 ... Cavity resonator 3 ... Input signal 11, 12 ... Output signal 13, 14 ... Resonance frequency 15, 16 ... Electric field strength peak value 17 ... Resonance Frequency difference 18 ... Electric field strength difference 21, 41 ... Dielectric constant conversion curves 31, 32, 33, 34, 35, 36 ... Resonant frequencies 31a, 32a, 33a represented by a quadratic expression of cell size 34a, 35a, 36a ... Resonance frequency true value 42 ... Dielectric constant conversion curve enlarged region 43 ... Measured value JIS-R1641 51 ... Input terminal 52 ... Output terminals 53, 54 .... Coaxial cable 55 ... Network analyzer 56, 57 ... Antenna or probe 58 ... Electric field energy distribution 59 ... Position with the highest electric field energy

Claims (7)

Assuming at least two types of dielectric constant of the sample,
The resonance frequency difference between the case where the sample having each dielectric constant is inserted into a predetermined cavity resonator and the case where the sample is not inserted is calculated using a predetermined electromagnetic field simulation. ,
A dielectric constant conversion curve is created from the two or more kinds of dielectric constants and the calculated resonance frequency difference of each numerical calculation,
Measure the respective resonance frequencies when the sample is inserted into the cavity resonator and not insert the sample to obtain the resonance frequency difference between them (hereinafter referred to as the resonance frequency difference by measurement),
A dielectric constant measurement method comprising: calculating a dielectric constant of the sample by comparing a resonance frequency difference obtained by the measurement with the dielectric constant conversion curve. The sample is
2. The dielectric constant measurement method according to claim 1, wherein the dielectric constant is measured at a position where the electric field energy accumulated in the space occupied by the sample is maximized inside the cavity resonator. The input terminal and output terminal provided in the cavity resonator are
The dielectric constant measuring method according to claim 1, further comprising a probe or a small hole having a length of 15 mm or less. The input terminal and output terminal provided in the cavity resonator are
The dielectric constant measurement method according to claim 1, further comprising a probe or an antenna having a length corresponding to 7.5% or less of a wavelength of resonance generated in the cavity resonator. The predetermined electromagnetic field simulation is a means for dividing an electromagnetic field space into cells of a predetermined size, calculating Maxwell's equations from the center difference of the cells, and calculating a resonance frequency,
Changing the dimensions of the cell by at least two or more types, and executing the predetermined electromagnetic field simulation in each of them,
2. The dielectric constant measurement method according to claim 1, wherein a resonance frequency when the cell size is set to 0 is estimated from the size of the two or more types of cells and the resonance frequency obtained from each simulation. . As the dielectric constant of the sample used for the predetermined electromagnetic field simulation,
The dielectric constant measurement method according to claim 1, wherein the electromagnetic field simulation is performed assuming two or more kinds of dielectric constants sandwiching a dielectric constant estimated from a dielectric material forming the sample. The dielectric constant conversion curve is
The dielectric constant measurement method according to claim 1, wherein the dielectric constant measurement method is created by a polynomial having the resonance frequency difference as a parameter.

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