U.S. patent application number 17/547400 was filed with the patent office on 2022-06-23 for measurement unit.
This patent application is currently assigned to NHK Spring Co., Ltd.. The applicant listed for this patent is NHK Spring Co., Ltd.. Invention is credited to Tsuyoshi Inuma, Hiroshi Nakayama, Shuji Takahashi.
Application Number | 20220196704 17/547400 |
Document ID | / |
Family ID | |
Filed Date | 2022-06-23 |
United States Patent
Application |
20220196704 |
Kind Code |
A1 |
Inuma; Tsuyoshi ; et
al. |
June 23, 2022 |
MEASUREMENT UNIT
Abstract
A measurement unit includes: a ground portion forming a part of
a line configured to provide continuity for grounding electric
potential, the ground portion including a surface forming a plane
at one end of the ground portion; a signal portion forming a part
of a line configured to provide continuity for a signal for
measurement, the signal portion including an end portion configured
to come out in a plane that is same as the plane of the ground
portion; an insulative dielectric portion provided between the
ground portion and the signal portion; an electrically conductive
first contact probe configured to expand and contract along a
longitudinal axis, the first contact probe coming into contact with
the signal portion; and an electrically conductive second contact
probe configured to expand and contract along a longitudinal axis,
the second contact probe coming into contact with the ground
portion.
Inventors: |
Inuma; Tsuyoshi; (Kanagawa,
JP) ; Nakayama; Hiroshi; (Kanagawa, JP) ;
Takahashi; Shuji; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NHK Spring Co., Ltd. |
Yokohama-shi |
|
JP |
|
|
Assignee: |
NHK Spring Co., Ltd.
Yokohama-shi
JP
|
Appl. No.: |
17/547400 |
Filed: |
December 10, 2021 |
International
Class: |
G01R 1/067 20060101
G01R001/067; H01B 11/18 20060101 H01B011/18; G01R 1/073 20060101
G01R001/073 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 17, 2020 |
JP |
2020-209745 |
Claims
1. A measurement unit comprising: a ground portion forming a part
of a line configured to provide continuity for grounding electric
potential, the ground portion including a surface at one end of the
ground portion, the surface forming a plane; a signal portion
forming a part of a line configured to provide continuity for a
signal for measurement, the signal portion including an end portion
configured to come out in a plane that is same as the plane of the
ground portion; a dielectric portion provided between the ground
portion and the signal portion, the dielectric portion being
insulative; a first contact probe configured to expand and contract
along a longitudinal axis, the first contact probe being
electrically conductive and coming into contact with the signal
portion; and a second contact probe configured to expand and
contract along a longitudinal axis, the second contact probe being
electrically conductive and coming into contact with the ground
portion.
2. The measurement unit according to claim 1, further comprising: a
ground plate; and a coaxial cable connected to the ground plate,
wherein the coaxial cable comprises: a signal conductor forming the
part of the line of the signal portion; a dielectric provided
around the signal conductor; and a ground conductor provided around
the dielectric, the signal conductor forms the signal portion, the
dielectric forms the dielectric portion, and the ground conductor
and the ground plate form the ground portion.
3. The measurement unit according to claim 2, wherein the ground
plate includes a through hole formed in the ground plate, and the
ground conductor is inserted into the through hole.
4. The measurement unit according to claim 2, wherein the ground
plate includes a through hole formed in the ground plate, the
dielectric is inserted into the through hole, and the ground
conductor is electrically connected to a surface of the ground
plate.
5. The measurement unit according to claim 1, further comprising: a
ground plate; and a coaxial cable connected to the ground plate,
wherein the ground plate comprises: a signal relaying portion
forming the part of the line of the signal portion; and a ground
plate dielectric configured to cover an outer periphery of the
signal relaying portion, the coaxial cable comprises: a signal
conductor forming the part of the line of the signal portion and
electrically connected to the signal relaying portion; a cable
dielectric provided around the signal conductor; and a ground
conductor provided around the cable dielectric and electrically
connected at a position different from positions of the signal
relaying portion and ground plate dielectric of the ground plate,
wherein the signal relaying portion and the signal conductor form
the signal portion, the ground plate dielectric and the cable
dielectric form the dielectric portion, and the ground conductor
and the ground plate form the ground portion.
6. The measurement unit according to claim 2, wherein a plurality
of the coaxial cables are connected to the ground plate.
7. The measurement unit according to claim 3, wherein a plurality
of the coaxial cables are connected to the ground plate.
8. The measurement unit according to claim 4, wherein a plurality
of the coaxial cables are connected to the ground plate.
9. The measurement unit according to claim 5, wherein a plurality
of the coaxial cables are connected to the ground plate.
10. The measurement unit according to claim 1, further comprising:
a coaxial cable including: a signal conductor forming the line of
the signal portion; a dielectric provided around the signal
conductor and forming the dielectric portion; and a ground
conductor provided around the dielectric and forms the ground
portion, wherein the ground conductor comprises: a tubular portion
extending along the signal conductor and the dielectric; and a flat
plate portion provided at an end portion of the tubular portion,
the flat plate portion being tabular, and end faces of the signal
conductor and the dielectric are positioned in a same plane as a
surface of the flat plate portion.
11. The measurement unit according to claim 10, further comprising
a plurality of groups each including the signal conductor, the
dielectric, and the tubular portion.
12. The measurement unit according to claim 1, further comprising:
a first connecting portion including the ground portion, the signal
portion, and the dielectric; and a second connecting portion
including the ground portion, the signal portion, and the
dielectric and provided opposite to the first connecting portion,
wherein one end of each of the first and second contact probes
comes into contact with the first connecting portion and the other
end of each of the first and second contact probes comes into
contact with the second connecting portion.
Description
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2020-209745, filed on
Dec. 17, 2020, the entire contents of which are incorporated herein
by reference.
BACKGROUND
[0002] The present disclosure relates to a measurement unit.
[0003] For inspecting continuity states or operating
characteristics of targets to be inspected, such as semiconductor
integrated circuits or liquid crystal panels, a cable to be
connected to an inspection device and a connecting member to be
connected to an opposite end portion of the cable have been used,
the opposite end portion being opposite to an end portion of the
cable, the end portion being near the inspection device (see, for
example, Japanese Patent No. 4678993). The cable has a signal
conductor in the center, a dielectric that covers the signal
conductor, and a ground conductor that covers the dielectric. The
connecting member has a central contact to be connected to the
signal conductor and a side contact to contact the ground
conductor.
SUMMARY
[0004] The opposite end portion of the cable in the configuration
described in Japanese Patent No. 4678993 is cut diagonally to be
connected to the connecting member. The transmission line changes
from a coaxial line to a so-called coplanar line at this connected
portion and this line change tends to generate noise.
[0005] There is a need for a measurement unit that enables
reduction in noise.
[0006] According to one aspect pf the present disclosure, there is
provided a measurement unit including: a ground portion forming a
part of a line configured to provide continuity for grounding
electric potential, the ground portion including a surface at one
end of the ground portion, the surface forming a plane; a signal
portion forming a part of a line configured to provide continuity
for a signal for measurement, the signal portion including an end
portion configured to come out in a plane that is same as the plane
of the ground portion; a dielectric portion provided between the
ground portion and the signal portion, the dielectric portion being
insulative; a first contact probe configured to expand and contract
along a longitudinal axis, the first contact probe being
electrically conductive and coming into contact with the signal
portion; and a second contact probe configured to expand and
contract along a longitudinal axis, the second contact probe being
electrically conductive and coming into contact with the ground
portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a diagram illustrating a configuration of a
measurement system according to an embodiment;
[0008] FIG. 2 is a diagram illustrating a configuration of a part
of the measurement system illustrated in FIG. 1;
[0009] FIG. 3 is a diagram illustrating a detailed configuration of
probes held in a probe holder;
[0010] FIG. 4 is a diagram illustrating a mode of connection
between the probes and a ground plate;
[0011] FIG. 5 is an enlarged view of a part of FIG. 4;
[0012] FIG. 6 is a diagram illustrating a configuration of the
ground plate and a coaxial cable;
[0013] FIG. 7 is a diagram illustrating a configuration of a ground
plate and a coaxial cable, according to a first modified
example;
[0014] FIG. 8 is a diagram illustrating a configuration of a ground
plate and a coaxial cable, according to a second modified
example;
[0015] FIG. 9 is a diagram illustrating a configuration of a
coaxial cable according to a third modified example;
[0016] FIG. 10 is a diagram illustrating a configuration of a
coaxial cable according to a fourth modified example; and
[0017] FIG. 11 is a perspective view illustrating an example of a
mode of contact between the coaxial cable and probes, according to
the fourth modified example.
DETAILED DESCRIPTION
[0018] A mode for implementing the present disclosure (hereinafter,
referred to as an "embodiment") will hereinafter be described by
reference to the appended drawings. The drawings are schematic, a
relation between a thickness and a width of each portion and ratios
among thicknesses of respective portions may be different from the
actual relation and ratios, and the drawings may also include a
portion that differs in its dimensional relations or ratios among
the drawings.
[0019] FIG. 1 is a diagram illustrating a configuration of a
measurement system according to an embodiment. FIG. 2 is a diagram
illustrating a configuration of a part of the measurement system
illustrated in FIG. 1. FIG. 2 illustrates a configuration in a
measurement unit 1 and excluding a probe holder 3 described later.
The measurement system includes the measurement unit 1, a
measurement device 100 that inputs and outputs signals from and to
a measurement target, and connecting cables 110 and 120 that
connect the measurement unit 1 and the measurement device 100 to
each other.
[0020] The measurement unit 1 includes contact probes 2
(hereinafter, simply referred to as "probes 2"), the probe holder 3
that holds the probes 2, a first ground plate 4, a second ground
plate 5, a first coaxial line portion 6, and a second coaxial line
portion 7.
[0021] FIG. 3 is a diagram illustrating a detailed configuration of
probes held in a probe holder. The probes 2 have electric
conductivity and are connected to the first ground plate 4 and the
second ground plate 5 at both ends of their longitudinal lengths.
The probes 2 are formed using an electrically conductive material,
and each include a first plunger 21 to contact the first ground
plate 4, a second plunger 22 to contact the second ground plate 5,
and a coil spring 23 that is provided between the first plunger 21
and the second plunger 22 and couples the first plunger 21 and the
second plunger 22 together to enable the probe 2 to expand and
contract. The first plunger 21 and second plunger 22 and the coil
spring 23 that form the probe 2, share the same axis.
[0022] The probe holder 3 is formed using an insulating material,
such as resin, machinable ceramic, or silicone, and is formed of a
first member 31 positioned higher in FIG. 3 and a second member 32
positioned lower in FIG. 3 that are layered over each other. The
first member 31 and the second member 32 have the same number of
holder holes 33 or 34 respectively formed therein for holding the
plural probes 2, and the holder holes 33 and 34 to hold the probes
2 are formed such that the axes of the holder holes 33 and 34 are
aligned with each other. Positions at which the holder holes 33 and
34 are formed are determined according to a layout pattern of the
probes 2.
[0023] When the probe holder 3 is placed between the first ground
plate 4 and the second ground plate 5, the coil spring 23 is
brought into a state of being compressed along a longitudinal
direction by contact loads from these ground plates.
[0024] A mode of connection between the probes 2 and the first
ground plate 4 and second ground plate 5 will be described next.
FIG. 4 is a diagram illustrating a mode of connection between
probes and a ground plate. FIG. 5 is an enlarged view of a part of
FIG. 4. FIG. 6 is a diagram illustrating a configuration of the
ground plate and a coaxial cable. In FIG. 6, (a) is a sectional
view of a configuration having the second ground plate 5 and a
coaxial cable 71 connected to each other. In FIG. 6, (b) is a plan
view of the second ground plate 5 as viewed from a side opposite to
a side to which the coaxial cable 71 is connected. FIG. 6
illustrates the connection between the second ground plate 5 and
the coaxial cable 71, but connection between the first ground plate
4 and a coaxial cable 61 has a similar configuration.
[0025] The first ground plate 4 is formed using an electrically
conductive material and is plate-shaped. The first ground plate 4
has, formed therein, a through hole 4a penetrating the first ground
plate 4 in its plate thickness direction (see FIG. 2). The through
hole 4a is a hole extending with a diameter that is approximately
equivalent to a diameter of the outer circumference of the coaxial
cable 61 described later. Being approximately equivalent includes
being identical and having a slight difference due to manufacturing
errors.
[0026] The second ground plate 5 is formed using an electrically
conductive material and is plate-shaped. The second ground plate 5
has, formed therein, a through hole 5a penetrating the second
ground plate 5 in its plate thickness direction. The through hole
5a is a hole extending with a diameter that is approximately
equivalent to a diameter of the outer circumference of the coaxial
cable 71 described later.
[0027] The first ground plate 4 and the second ground plate 5 are
made of copper, nickel, or stainless steel, for example. The first
ground plate 4 and the second ground plate 5 may be formed of a
material that is the same as a material that forms ground
conductors 64 and 74 described later.
[0028] The first coaxial line portion 6 includes the coaxial cable
61. The coaxial cable 61 is held by a cable holding member 60.
Furthermore, an opposite end portion of the coaxial cable 61 is
inserted in the through hole 4a of the first ground plate 4, the
opposite end portion being opposite to an end of the coaxial cable
61, the end being connected to the connecting cable 110. The
coaxial cable 61 may be press-fitted in the through hole 4a, fixed
by soldering, for example, or fixed by a combination of these press
fitting and soldering.
[0029] The coaxial cable 61 has a signal conductor 62 that
transmits a signal from the measurement device 100, a dielectric 63
that is provided around the signal conductor 62 and is insulating,
and the ground conductor 64 provided around the dielectric 63 (see
FIG. 2). The signal conductor 62, the dielectric 63, and the ground
conductor 64 form a coaxial structure. The dielectric 63 and the
ground conductor 64 are each tubular. The ground conductor 64 is
made of copper, nickel, or stainless steel, for example. The
coaxial cable 61 thus has a configuration that is the same as that
of a so-called semi-rigid cable. In this embodiment, a signal
conductor forms a signal portion and a dielectric forms a
dielectric portion.
[0030] An end portion of the coaxial cable 61 is exposed from the
through hole 4a at a surface of the first ground plate 4, the end
portion being near the first ground plate 4. An end face of the
coaxial cable 61 and the surface of the first ground plate 4 are
thus positioned in the same plane, the surface being on a side of
the first ground plate 4, the side being where the end face of the
coaxial cable 61 comes out. Furthermore, the first ground plate 4
forms a ground portion by being electrically connected to the
ground conductor 64. The ground portion forms a part of a line that
provides continuity for grounding electric potential.
[0031] The second coaxial line portion 7 includes the coaxial cable
71. The coaxial cable 71 is held by a cable holding member 70.
Furthermore, an opposite end portion of the coaxial cable 71 is
inserted in the through hole 5a of the second ground plate 5, the
opposite end portion being opposite to an end of the coaxial cable
71, the end being connected to the connecting cable 120. The
coaxial cable 71 may be press-fitted in the through hole 5a, fixed
by soldering, for example, or fixed by a combination of these press
fitting and soldering.
[0032] The coaxial cable 71 has a signal conductor 72 that
transmits a signal from the measurement device 100, a dielectric 73
that is provided around the signal conductor 72, and the ground
conductor 74 provided around the dielectric 73. The signal
conductor 72, the dielectric 73, and the ground conductor 74 form a
coaxial structure. The dielectric 73 and the ground conductor 74
are each tubular. The ground conductor 74 is made of copper,
nickel, or stainless steel, for example. The coaxial cable 71 thus
has a configuration that is the same as that of a so-called
semi-rigid cable.
[0033] An end portion of the coaxial cable 71 is exposed from the
through hole 5a at a surface of the second ground plate 5, the end
portion being near the second ground plate 5. An end face of the
coaxial cable 71 and the surface of the second ground plate 5 are
thus positioned in the same plane, the surface being on a side of
the second ground plate 5, the side being where the end face of the
coaxial cable 71 comes out. Furthermore, the second ground plate 5
forms a ground portion as described above by being electrically
connected to the ground conductor 74.
[0034] In this embodiment, each of the coaxial cables 61 and 71
comes into contact with three probes 2. The first ground plate 4
and the coaxial cable 61 form a first connecting portion and the
second ground plate 5 and the coaxial cable 71 form a second
connecting portion. The measurement system may include at least one
of the first and second connecting portions, and any other publicly
known mode of connection may be adopted for the other one of the
first and second connecting portions.
[0035] One end (the first plunger 21 herein) of each of the probes
2 comes into contact with any one of the signal conductor 62 and
the ground conductor 64, at the end portion of the coaxial cable
61, the end portion coming out from the first ground plate 4. In
FIG. 4 and FIG. 5, one of the probes 2 comes into contact with the
signal conductor 62 and the other two of the probes 2 come into
contact with the ground conductor 64. As to the coaxial cable 71,
similarly, the probe 2 that comes into contact with the signal
conductor 62 comes into contact with the signal conductor 72, and
the other two probes 2 that come into contact with the ground
conductor 64 come into contact with the ground conductor 74.
Central axes of the coaxial cables 61 and 71 and central axes of
the probes 2 are thus either aligned with each other or extend
parallel to each other, in their longitudinal directions.
[0036] In the drawings, the probe 2 (a first contact probe) that
comes into contact with the signal conductors 62 and 72 is
illustrated as a probe 2S and the probes 2 (second contact probes)
that come into contact with the ground conductors 64 and 74 are
illustrated as probes 2G. Parts with which the probes 2G come into
contact may be a surface of the first ground plate 4 and a surface
of the second ground plate 5, without being limited to the ground
conductors 64 and 74.
[0037] The minimum pitch between the probes 2 is a radius of the
inner circumference of a ground conductor. For example, in a case
where the probes 2 are caused to contact a central portion of the
ground conductor at an end face of a coaxial cable, the pitch
between the probes is determined by (diameter of outer
circumference of ground conductor+diameter of inner circumference
of ground conductor)/2/2.
[0038] According to the above described embodiment, an end face of
a signal conductor of a coaxial cable and an end face of a ground
portion formed of a ground conductor and a ground plate are
positioned in the same plane, and plural probes are brought into
contact with the signal conductor and the ground portion to achieve
continuity for a signal line and a ground line. This embodiment
enables a coaxial line to be maintained and thus unchanged in form,
contrary to the conventional configuration, and as a result,
enables reduction in noise.
[0039] Furthermore, because the plural probes 2 to be connected to
a coaxial cable are individually provided in the above described
embodiment, the pitch between the probes 2 and the number and
layout of the probes 2G to be connected to a ground portion are
able to be freely set. Therefore, the measurement unit 1 is able to
be used for various types of measurement without being limited by
the mode of connection.
[0040] A configuration using a single coaxial cable has been
described above with respect to the embodiment, but a configuration
including a ground plate that is provided with plural through holes
and holds plural coaxial cables may be adopted instead.
[0041] FIG. 7 is a diagram illustrating a configuration of a ground
plate and a coaxial cable, according to a first modified example.
In FIG. 7, (a) is sectional view of a configuration having a second
ground plate and a coaxial cable connected to each other. In FIG.
7, (b) is a plan view of the second ground plate as viewed from an
opposite side of the second ground plate, the opposite side being
opposite to a side of the second ground plate, the side being where
the coaxial cable is connected. A measurement unit according to
this first modified example has, provided therein, a second ground
plate 5A instead of the second ground plate 5 described above, and
a coaxial cable 71A instead of the coaxial cable 71. Description of
any configuration that is the same as that of the embodiment
described above will hereinafter be omitted.
[0042] The coaxial cable 71A has a signal conductor 72, a
dielectric 73, and a ground conductor 74A that is provided around
the dielectric 73. The signal conductor 72, the dielectric 73, and
the ground conductor 74A form a coaxial structure. The ground
conductor 74A is made of copper, nickel, or stainless steel, for
example. The coaxial cable 71A thus has a configuration that is the
same as that of a so-called semi-rigid cable.
[0043] At an end portion of the ground conductor 74A, the ground
conductor 74A is shorter than the signal conductor 72 and the
dielectric 73 by a length corresponding to a thickness of the
second ground plate 5A, the end portion being at an end of the
ground conductor 74A, the end being connected to the second ground
plate 5A. Therefore, the outer periphery of the dielectric 73 is
exposed at the end portion of the ground conductor 74A, the end
portion being at the end to be connected to the second ground plate
5A.
[0044] The second ground plate 5A is formed using an electrically
conductive material and is plate-shaped. The second ground plate 5A
has, formed therein, a through hole 5b penetrating the second
ground plate 5A in its plate thickness direction. The through hole
5b is a hole extending with a diameter that is approximately
equivalent to a diameter of the outer circumference of the
dielectric 73.
[0045] The coaxial cable 71A is connected to the second ground
plate 5A by insertion of the dielectric 73 into the through hole
5b. The dielectric 73 of the coaxial cable 71A may be press-fitted
into the through hole 5b, the dielectric 73 may be fixed to the
second ground plate 5A by soldering, for example, or the coaxial
cable 71A may be fixed by a combination of these press-fitting and
soldering. Upon the press-fitting and/or soldering, the ground
conductor 74A comes into contact with a surface of the second
ground plate 5A. The second ground plate 5A and the ground
conductor 74A are thereby electrically connected to each other. The
ground conductor 74A and the second ground plate 5A may be fixed to
each other by soldering, for example, to be electrically connected
to each other.
[0046] End portions of the signal conductor 72 and dielectric 73 of
the coaxial cable 71A are exposed from the through hole 5b at a
surface of the second ground plate 5A. End faces of the signal
conductor 72 and dielectric 73 and the surface of the second ground
plate 5A are thus positioned in the same plane, the surface being
on a side of the second ground plate 5A, the side being where an
end face of the coaxial cable 71A comes out.
[0047] The probe 2S comes into contact with the signal conductor 72
that comes out from the through hole 5b. The probes 2G, on the
other hand, come into contact with the surface of the second ground
plate 5A.
[0048] In the above described first modified example also, an end
face of a signal conductor of a coaxial cable and an end face of a
ground portion formed of a ground conductor and a ground plate are
positioned in the same plane, and plural probes are brought into
contact with the signal conductor and the ground portion to achieve
continuity for a signal line and a ground line. This first modified
example enables a coaxial line to be maintained and thus unchanged
in form, contrary to the conventional configuration, and as a
result, enables reduction in noise. Furthermore, similarly to the
embodiment, the first modified example enables the freedom of the
layout of the probes 2 to be increased and is thus able to be
adapted to various types of measurement.
[0049] FIG. 8 is a diagram illustrating a configuration of a ground
plate and a coaxial cable, according to a second modified example.
In FIG. 8, (a) is a sectional view of a configuration having a
second ground plate and a coaxial cable connected to each other. In
FIG. 8, (b) is a plan view of the second ground plate as viewed
from a side opposite to a side to which the coaxial cable is
connected. A measurement unit according to this second modified
example, has, provided therein, a second ground plate 5B instead of
the second ground plate 5 described above, and a coaxial cable 71B
instead of the coaxial cable 71. Description of any configuration
that is the same as that of the embodiment described above will
hereinafter be omitted.
[0050] The coaxial cable 71B has a first signal conductor 72A (a
signal conductor) that transmits a signal from the measurement
device 100, a first dielectric 73A (a cable dielectric) provided
around the first signal conductor 72A, and a ground conductor 74A
provided around the first dielectric 73A. The first signal
conductor 72A, the first dielectric 73A, and the ground conductor
74A form a coaxial structure, and their end faces are positioned in
the same plane, the end faces being at their ends to be connected
to the second ground plate 5B.
[0051] The second ground plate 5B is formed using an electrically
conductive material and is plate-shaped. The second ground plate 5B
has a second signal conductor 51 (a signal relaying portion) and a
second dielectric 52 (a ground plate dielectric) covering the outer
periphery of the second signal conductor 51. In this second
modified example, the first signal conductor 72A and the second
signal conductor 51 form a signal portion and the first dielectric
73A and the second dielectric 52 form a dielectric portion.
[0052] The second ground plate 5B has, formed therein, a through
hole 5b penetrating the second ground plate 5B in its plate
thickness direction. The through hole 5b is a hole extending with a
diameter that is approximately equivalent to a diameter of the
outer circumference of the second dielectric 52. The second
dielectric 52 of the second signal conductor 51 and second
dielectric 52 is fixed in the through hole 5b. Upon the fixing, end
faces of the second signal conductor 51 and second dielectric 52
are positioned in the same plane as a surface of the main body of
the second ground plate 5B.
[0053] The second signal conductor 51 and the first signal
conductor 72A preferably have the same diameter. Furthermore, the
second dielectric 52 and the first dielectric 73A preferably have
the same diameter. In addition, the first dielectric 73A and the
second dielectric 52 may be formed using the same material, or may
be formed using materials different from each other.
[0054] The coaxial cable 71B is connected to the second ground
plate 5B by being fixed in a state where the first signal conductor
72A has been brought into contact with the second signal conductor
51. Upon this connection, the ground conductor 74A comes into
contact with a surface of the second ground plate 5B. The second
ground plate 5B and the ground conductor 74A are thereby
electrically connected to each other. The first signal conductor
72A and the second signal conductor 51 may be electrically
connected to each other by being fixed to each other by soldering,
for example. Furthermore, the second ground plate 5B and the ground
conductor 74A may be electrically connected to each other by being
fixed to each other by soldering, for example.
[0055] Furthermore, the probe 2S comes into contact with an
opposite end of the second signal conductor 51 to be electrically
connected thereto, the opposite end being opposite to an end of the
second signal conductor 51, the end being an end with which the
first signal conductor 72A comes into contact. The probes 2G come
into contact with an opposite surface of surfaces of the second
ground plate 5B to be electrically connected thereto, the opposite
surface being opposite to the surface with which the ground
conductor 74A comes into contact.
[0056] In the above described second modified example also, an end
face of a signal conductor of a coaxial cable and an end face of a
ground portion formed of a ground conductor and a ground plate are
positioned in the same plane, and plural probes are brought into
contact with the signal conductor and the ground portion to achieve
continuity for a signal line and a ground line. This second
modified example enables a coaxial line to be maintained and thus
unchanged in form, contrary to the conventional configuration, and
as a result, enables reduction in noise. Furthermore, similarly to
the embodiment, the second modified example enables the freedom of
the layout of the probes 2 to be increased and is thus able to be
adapted to various types of measurement.
[0057] FIG. 9 is a diagram illustrating a configuration of a
coaxial cable according to a third modified example. In FIG. 9, (a)
is a sectional view of the coaxial cable. In FIG. 9, (b) is a plan
view of the coaxial cable. A measurement unit according to this
third modified example does not have the second ground plate 5
described above, and is provided with a coaxial cable 71C instead
of the coaxial cable 71. Description of any configuration that is
the same as that of the embodiment described above will be
omitted.
[0058] The coaxial cable 71C has the signal conductor 72 and
dielectric 73 described above, and a ground conductor 74B covering
the outer periphery of the dielectric 73. The signal conductor 72,
the dielectric 73, and the ground conductor 74B form a coaxial
structure.
[0059] The ground conductor 74B has a tubular portion 741 extending
along a longitudinal direction of the coaxial cable 71C (the
dielectric 73), and a flat plate portion 742 that is provided at an
end portion of the tubular portion 741 and is tabular. End faces of
the signal conductor 72 and dielectric 73 are thus positioned in
the same plane as a surface of the flat plate portion 742, the end
faces being at ends of the signal conductor 72 and dielectric 73,
the ends being where the signal conductor 72 and dielectric 73 are
exposed on the surface of the flat plate portion 742. In this third
modified example, the ground conductor 74B forms a ground
portion.
[0060] The probe 2S comes into contact with the signal conductor 72
that comes out from the flat plate portion 742. The probes 2G, on
the other hand, come into contact with the surface of the flat
plate portion 742.
[0061] In this third modified example described above also, an end
face of a signal conductor of a coaxial cable and a surface of a
ground conductor (a flat plate portion) are positioned in the same
plane, and plural probes are brought into contact with the signal
conductor and the ground conductor to achieve continuity for a
signal line and a ground line. This third modified example enables
a coaxial line to be maintained and thus unchanged in form,
contrary to the conventional configuration, and as a result,
enables reduction in noise. Furthermore, similarly to the
embodiment, the third modified example enables the freedom of the
layout of the probes 2 to be increased and is thus able to be
adapted to various types of measurement.
FOURTH MODIFIED EXAMPLE
[0062] FIG. 10 is a diagram illustrating a configuration of a
coaxial cable according to a fourth modified example. In FIG. 10,
(a) is a sectional view of the coaxial cable. In FIG. 10, (b) is a
plan view of the coaxial cable. A measurement unit according to
this fourth modified example does not have the second ground plate
5 described above, and is provided with a coaxial cable 71D instead
of the coaxial cable 71. Description of any configuration that is
the same as that of the embodiment described above will be
omitted.
[0063] The coaxial cable 71D has the signal conductors 72 and the
dielectrics 73 described above, and a ground conductor 74C covering
the outer peripheries of the dielectrics 73.
[0064] The ground conductor 74C has a first tubular portion 743
that covers the dielectric 73, a second tubular portion 744 that
covers the dielectric 73 different from the dielectric 73 covered
by the first tubular portion 743, and a flat plate portion 745 that
is provided at an end portion of the first tubular portion 743 and
second tubular portion 744 and is tabular. End faces of the signal
conductors 72 and the dielectrics 73 and a surface of the flat
plate portion 745 are positioned in the same plane, the end faces
being at ends of the signal conductors 72 and the dielectrics 73,
the ends being where the signal conductors 72 and the dielectrics
73 are exposed on the surface of the flat plate portion 745.
[0065] In this fourth modified example, two probes 2S and three
probes 2G are provided. FIG. 11 is a perspective view illustrating
an example of a mode of contact between the coaxial cable and
probes, according to the fourth modified example. One of the probes
2S comes into contact with one of the signal conductors 72 that
come out from the flat plate portion 745. The other one of the
probes 2S comes into contact with the other one of the signal
conductors 72 that come out from the flat plate portion 745.
Furthermore, one of the probes 2G is positioned between (inward
from) the probes 2S and comes into contact with the surface of the
flat plate portion 745. The remaining two of the probes 2G are each
positioned outward from the two probes 2S and come into contact
with the surface of the flat plate portion 745.
[0066] The layout and number of the probes 2G are not limited to
the layout and number provided in FIG. 11, and various
modifications are possible. For example, a configuration without
the probe 2G provided between the two probes 2S may be adopted
instead.
[0067] In this fourth modified example described above also, an end
face of a signal conductor of a coaxial cable and a surface of a
ground conductor (a flat plate portion) are positioned in the same
plane, and plural probes are brought into contact with the signal
conductor and the ground conductor to achieve continuity for a
signal line and a ground line. This fourth modified example enables
a coaxial line to be maintained and thus unchanged in form,
contrary to the conventional configuration, and as a result,
enables reduction in noise. Furthermore, similarly to the
embodiment, the fourth modified example enables the freedom of the
layout of the probes 2 to be increased and is thus able to be
adapted to various types of measurement.
[0068] With respect to the first to fourth modified examples, a
configuration including a second ground plate and a coaxial cable
connected to the second ground plate and a configuration without
the second ground plate have been described above, but the first to
fourth modified examples are also applicable to a configuration
including a first ground plate and a coaxial cable connected to the
first ground plate and any one of the above described
configurations may be adopted for the mode of connection between
the probes 2 and the coaxial cable. For such connection, the same
configurations may be combined together or configurations different
from each other may be combined together.
[0069] A mode for implementing the present disclosure has been
described thus far, but the present disclosure is not to be limited
only to the above described embodiment. For example, a ground plate
may be configured to have an insulating portion as long as
continuity is achieved between the probes 2G and the ground
plate.
[0070] The configuration of contact probes described herein is just
an example, and various types of probes conventionally known may be
used. For example, without being limited to the above described
configuration having plungers and a coil spring, probes to be used
may each be: a probe including a pipe member; a pogo pin; a solid
electrically conductive member; an electrically conductive pipe; a
wire; or a connecting terminal (a connector) that connects electric
contact points together, or any combination of these different
types of probes may be adopted as appropriate.
[0071] The measurement unit is suitable for reducing noise, as
described above.
[0072] The present disclosure has an effect of enabling reduction
in noise.
[0073] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the disclosure in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general concept as defined by the appended claims
and their equivalents.
* * * * *