Dielectric constant measurement method, dielectric measurement device and dielectric measurement program

Patent metadata

Field	Value
Publication number	US-12025642-B2
Application number	US-201917786867-A
Country	US
Kind code	B2
Filing date	Dec 20, 2019
Priority date	Dec 20, 2019
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

A permittivity measuring method includes measuring a set of phases at sampling frequencies of at least three points in each of a first-half portion and a second-half portion of a phase characteristic of electromagnetic waves that passed through a measurement target, if the mode of the phase changes of both sets of phases belongs to a phase group in which change of the at least three points in the first half and change of at least three points in the second half are both monotonic change, maximal values, or minimal values, calculating the permittivity using the phase slope of the phases in the first-half portion and the phases in the second-half portion, and if the mode of the phase changes does not belong to the phase group, calculating the permittivity by fitting the phases of either the first half or the second half to a quadratic function.

First claim

The invention claimed is:

1. A permittivity measuring method comprising:
measuring a first set of phases at sampling frequencies of at least three points in a first-half portion of a phase characteristic of electromagnetic waves that passed through a measurement target or a second set of phases at sampling frequencies of at least three points in a second-half portion of the phase characteristic;
determining whether or not a phase change of the measured first or second set of phases has an extreme value;
in response to a determination that the phase change of the measured first or second set of phases has the extreme value, calculating a permittivity by fitting the measured first or second set of phases to a quadratic function; and
in response to a determination that the phase change of the measured first or second set of phases does not have the extreme value:
measuring the other set of the first and second set of phases;
determining a mode of the phase changes of both the first and second sets of phases;
in response to the mode of the phase changes of both the first and second sets of phases belonging to a phase group in which change of at least three points in a first half and change of at least three points in a second half are both monotonic change, are both maximal values, or are both minimal values, calculating the permittivity using a phase slope of the phases at the sampling frequencies of the at least three points in the first-half portion and the phases at the sampling frequencies of the at least three points in the second-half portion; and
in response to the mode of the phase changes of both the first and second sets of phases not belonging to the phase group, calculating the permittivity by fitting the other set of the first and second phases to a quadratic function;

wherein an interval between the sampling frequencies of the at least three points in the first-half portion and an interval f s between the sampling frequencies of the at least three points in the second-half portion satisfies

f
s

<

c

1
⁢
6
⁢

ε

eff
⁢
_
⁢
m
⁢
a
⁢
x

⁢
L

,

in which L is a thickness of the measurement target, c is the speed of light, and ε eff_max is a maximum value that can be taken by an effective permittivity of the measurement target; and
wherein an interval f p between a lowest sampling frequency among the sampling frequencies of the at least three points in the first-half portion and a highest sampling frequency among the sampling frequencies of the at least three points in the second-half portion satisfies

f
p

<

c

(

ε

eff
⁢
_
⁢
m
⁢
a
⁢
x

-
1

)

⁢
L

.

2. The permittivity measuring method according to claim 1 , further comprising:
in response to the mode of the phase changes of both the first and second sets of phases belonging to the phase group in which change of the at least three points in the first half and change of the at least three points in the second half are both monotonic change, are both maximal values, or are both minimal values, measuring the phase at N sampling frequencies between the first-half portion and the second-half portion;
determining whether or not a phase jump has occurred between the N sampling frequencies and the first-half portion or the second-half portion; and
in response to a determination that the phase jump has occurred, performing phase connection processing, wherein an interval f p_N between a lowest sampling frequency among the sampling frequencies of the at least three points in the first-half portion and a highest sampling frequency among the sampling frequencies of the at least three points in the second-half portion satisfies

f

p
⁢
_
⁢
N

<

Nc

(

ε

eff
⁢
_
⁢
m
⁢
a
⁢
x

-
1

)

⁢
L

⁢

N
=
1

,
2
,

3
⁢

…

.

3. A system for performing the permittivity measuring method according to claim 1 , wherein the system comprises:
a light source;
a measuring device configured to measure the electromagnetic waves emitted from the light source; and
an analyzer configured to calculate the permittivity using the electromagnetic waves measured by the measuring device.

4. A permittivity measuring method comprising:
measuring a first set of phases at sampling frequencies of at least three points in a first-half portion of a phase characteristic of electromagnetic waves that passed through a measurement target and a second set of phases at sampling frequencies of at least three poi

Assignees

• Nippon Telegraph & Telephone

Inventors

• Jo Teruo
• Hamada Hiroshi
• Nosaka Hideyuki

Classifications

• G01N21/3581

  using far infrared light; using Terahertz radiation · CPC title

• G01R27/2617 Primary

  Measuring dielectric properties, e.g. constants (testing dielectric strength G01R31/12; detecting insulation faults G01R31/52; G01R27/2688 takes precedence) · CPC title