JPH0535834B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is suitable for use in measuring the three-dimensional magnetic field distribution of electromagnetic equipment (hereinafter referred to as an object to be measured) such as a deflection yoke device or a transformer. Concerning magnetic field measurement method.

[Prior art]

In general, deflection yoke devices, transformers, etc. use three components of the magnetic field (B _x , B _y , B _z ) is being measured.

For this reason, in the prior art, for example, a method as shown in FIG. 13 or 14 is used to measure the magnetic field distribution of a deflection yoke device.

First, FIG. 13 shows a magnetic field measurement method using two uniaxial probes. In the figure, reference numeral 1 denotes a deflection yoke device which is an object to be measured, and the deflection yoke device 1 is fixed to, for example, an X and Y stage (not shown) provided on a rotary table, and is movable in the X-axis and Y-axis directions. It is becoming. 2 is a probe that measures the magnetic fields B _x and B _y in the X- and Y-axis directions among the three components of the magnetic field, and inside the probe 2 there is a magnetic field such as a Hall effect element.
A sensor 2A consisting of an electrical conversion element is buried, attached to a probe fixture (not shown), and suspended. Reference numeral 3 designates a probe that similarly measures the magnetic field _Bz in the Z-axis direction among the three components of the magnetic field, and a sensor 3A is also embedded within the probe 3, attached to a probe fixture, and suspended.

To measure the three components B _x , B _y , and B _z of the magnetic field using the two probes 2 and 3, first place the probe 2 on the axis of the rotary table, and then
Probe 2 so that the direction of
Adjust the mounting angle. And the magnetic field in the X-axis direction
After measuring B _x , the probe 2 is left as it is, and the rotary table is rotated 90 degrees to measure the magnetic field B _y in the Y-axis direction. Next, probe 2 is replaced with probe 3. Then, the direction of sensor 3A is Z
By adjusting the mounting angle to match the axial direction and measuring the magnetic field _Bz in the Z-axis direction, the three-dimensional magnetic field distribution can be determined.

By the way, in the probes 2 and 3 used for such magnetic field measurements, the shapes of the sensors 2A and 3A are minute, so it is possible that the sensors 2A and 3A are mounted tilted as a manufacturing error of the probes 2 and 3. is always the case. If the sensors 2A, 3A are mounted with their orientations tilted and not aligned with the X, Y, and Z axes, magnetic field components that are not to be measured will be mixed into the measured values. Therefore, during measurement work, it is necessary to adjust the mounting angles of the probes 2 and 3 in a uniform magnetic field before starting the measurement. For this reason, in the case of the conventional technology described above, since two probes 2 and 3 are used, complicated operations are required, such as the need to replace each probe 2 and 3 and adjust the angle twice. It had the disadvantage of being rejected.

On the other hand, in order to eliminate the complexity of replacing probes and adjusting the installation angle as described above, a measurement method is adopted that uses one biaxial probe with two sensors built into one probe. It has become like that.

That is, FIG. 14 shows a measurement method using one biaxial probe, and in the figure, 4 indicates the three components of the magnetic field B _x ,
A biaxial probe for measuring B _y and B _z is shown, and inside the biaxial probe 4 there are magnetic fields B x , B _x in the X-axis and Y-axis directions,
Sensor 4A that measures B _y and magnetic field B _z in the Z-axis direction
By using the probe 4, the replacement work of the probes 2 and 3 as shown in FIG. 13 can be made unnecessary.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, although it is possible to eliminate the need to replace the attachment part of the probe 4, the orientation of the two sensors 4A and 4B is adjusted along two axes (X-
The disadvantage is that it is very difficult to adjust the angle to match Z or Y-Z at the same time, and in many cases it must be accepted as a measurement error.

Furthermore, since the two sensors 4A and 4B are built-in, the shape of the probe 4 inevitably becomes large, which narrows the measurement space and limits the collection of detailed data near the coil. It has the disadvantage of being

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and the present invention has been made to enable highly accurate three-dimensional magnetic field measurement of a measured object using one probe consisting of one sensor. The purpose of this study is to provide a method for measuring magnetic fields based on

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention is arranged on one axis at a predetermined angle (however, 0,
(π/2, excluding the other of the probe or the object to be measured is disposed on the probe or the object to be measured; of
This means that the three components of the magnetic field of the object to be measured are separated and determined based on the four signals output from the probe when the probe is rotated by 90 degrees.

Further, it is preferable that the three components of the magnetic field are determined separately using a rectangular coordinate system.

On the other hand, it is desirable that the three components of the magnetic field are determined separately using a cylindrical coordinate system.

[Effect]

With the above configuration, by rotating either the probe or the object to be measured by 90 degrees around one axis, a single sensor can generate four magnetic fields in different directions at a given position on the object to be measured. It can be detected as a signal, and from these four signals the magnetic field 3
Components can be determined with high precision.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 12.

1 to 10 show a first embodiment of the present invention. In this embodiment, a probe is disposed on the rotation axis (Z _M axis) for rotating the deflection yoke device, and the probe is arranged parallel to the Z _M axis. This is a case where a deflection yoke device as an object to be detected is arranged on another axis (Z-axis).

1 and 2 show the configuration of the measuring device used in this example. Reference numeral 11 denotes a rotating shaft rotated by a motor (not shown), and the rotational axis of the rotating shaft 11 is
Z is _{the M} axis. 12 is a turntable provided on the rotating shaft 11, and the turntable 12 is
It is designed to rotate around the Z and _M axes. 13
is provided on the turntable 12, and has an X axis,
The XY stage is movable in the Y-axis direction.
A deflection yoke fixture 14 for fixing the deflection yoke device 1 is fixedly provided on the stage 13, and the Z axis, which is the axis of the fixture 14, is parallel to the _ZM axis, and Axis, Y axis is XY
It can be changed arbitrarily by operating the stage 13.

On the other hand, reference numeral 15 indicates a probe fixture, and the fixture 15 is composed of a support 15A, a movable part 15B movable in the Z-axis direction of the support 15A, and a support arm 15C provided on the movable part 15B. Support arm 15C
A cylindrical probe 16 is fixedly supported at the tip of the probe 16, and a sensor 17 made of a magneto-electric conversion element is embedded within the probe 16. Reference numeral 18 indicates a signal line for taking out a signal from the sensor 17, and reference numeral 19 indicates an XY stage to which the support column 15A is attached. In addition,
In the embodiment, the XY stage 19 is the probe 1
6 is not necessarily necessary. Here, the probe 16 is adjusted to coincide with the axis of the Z _{and M} axes, and the sensor 17 is
As shown in the figure, it is arranged obliquely so that a predetermined mounting angle γ is provided between the unit normal vector 〓 erected on the magnetically sensitive portion 17A and the _ZM axis. As will be described later, it is a necessary and sufficient condition for the present invention that the angle γ is not 0, π/2, or π, and by setting the angle γ to π/4 or 3π/4, the three components of the magnetic field can be reduced. However, the sensitivity of the sensor 17 becomes equal.

Next, we will discuss the magnetic field measurement principle of the deflection yoke device using the measuring device configured as described above in the fourth section.
An example of measurement using a rectangular coordinate system and a cylindrical coordinate system will be described with reference to FIGS. Note that measuring the magnetic field of the deflection yoke device means separately extracting three components in the direction of the coordinate axes set in the deflection yoke device at each measurement point.

Here, if the position of the sensor 17A in the probe 16 with respect to the X, Y, and Z axes in FIGS. Rectangular coordinate system...P (x, y, z) Cylindrical coordinate system...P (r, θ, z) Therefore, the three components of the magnetic field at measurement point P are as follows: Cartesian coordinate system...(B _x , B _y , B _z ) Cylindrical system coordinates... can be given as (B _r , B〓, B _z ).

First, as the first three-component magnetic field separation method, the three components of the magnetic field (B _x , B _y ,
The following describes the case of measuring B _z ).

First, as shown in FIG. 6, the origin O is set at the center P of the magnetic sensing part 17A of the sensor 17, and local coordinate systems X, Y, and Z are set. Here, the unit normal vector perpendicular to the magnetic sensing part 17A of the sensor 17 is
is the unit normal vector 〓 and the local coordinate system X, Y,
Letting the angles with the Z axis be α, β, and γ, the following equation (1) is obtained.

〓=cosα〓+cosβ〓+cosγ〓=sinγ・cosδ〓+sinγ・sinδ〓+cosγ〓……(1) However, as shown in Fig. 6, the angle δ is from the X axis to the projection vector of the vector 〓 _onto the Z plane〓xy is the angle of

Also, if the magnetic field (magnetic flux density) at the measurement point P, that is, the origin O, is 〓, then 〓=B _x 〓 + B _y 〓 + B _z 〓 ...(2) Therefore, the output voltage of the sensor 17 (measured value)
V _H is given by the following equation (3).

_{V. _ _ _} The values characterizing the inclination of the sensor 17 are two angles γ and δ, and when the unit normal vector 〓 does not coincide with any of the X, Y, and Z axis directions, the output voltage V _H becomes B _x , B _y , B _z
It contains three components. Therefore, the output voltage
No matter what correction coefficient is applied to V _H , B _x , B _y ,
It is not possible to separate each component of B _z . In addition,
Of course, if the unit normal vector 〓 coincides with the coordinate axis direction, only one component out of the three components of the magnetic field 〓 can be measured independently.

Therefore, when the sensor 17 has an inclination, the three components B _x , B _y , and B _z of the magnetic field are separated from the output voltage V _H.
A method for separating three components of a magnetic field will be described.

First, in the sixth step, when the probe 16 is rotated counterclockwise by 90 degrees around the Z axis without moving the center P of the sensor 17,
Consider how the output voltage V _H can be obtained.
Specifically, as shown in FIGS. 1 and 2, the probe 16 is positioned on the _ZM axis, the deflection yoke device 1 is positioned on the Z axis, and the turntable 12
This can be achieved by rotating clockwise by 90 degrees.

Here, the rotation of the sensor 17 is the rotation of the unit normal vector 〓 about the Z axis. Therefore,
Since the Z component n _z of the unit normal vector 〓 does not change and is constant, it ends up being a rotation around the origin O of the projected vector 〓 _xy projected onto the Z plane (see Fig. 7).

Therefore, if the vector at the first rotational position of the projection vector = _xy is nx ₁ ny ₁ and this is the first quadrant, then the second, third, and fourth
The quadrant vectors 〓2nx ₂ ny ₂ , 〓3nx ₃ ny ₃ n ₄ nx ₄ ny ₄ are obtained by sequential linear transformation. That is, it is determined as follows.

〓1nx ₁ ny ₁ = sinγ・cosδ sinγ・sinδ 〓2nx ₂ ny ₂ = cosπ/2, −sinπ/2 sinπ/2, cosπ/2nx ₁ ny ₁ =0−1 1 0sinγ・cosδ sinγ・sinδ = −sinγ・sinδ sinγ・cosδ Similarly, 〓3nx ₃ ny ₃ =0−1 1 0nx ₂ ny ₂ = −sinγ・cosδ −sinγ・sinδ 〓4nx ₄ ny ₄ =0−1 1 0nx ₃ ny ₃ = sinγ・sinδ It is found as −sinγ・cosδ.

Therefore, when the sensor 17 is rotated counterclockwise by 90 degrees, the output voltages of the sensor 17 are V _H1 , V _H2 ,
V _H3 and V _H4 are as follows from V _H =k(〓, 〓).

When the rotation angle is 0: V _H1 = k (B _x · sin γ · cos δ + B _y · sin γ · sin δ + B _z · cos γ) When the rotation angle is π/2: V _H2 = k (−B _x · sin γ · sin δ + B _y · sinγ・cosδ＋B _z・cosγ) When the rotation angle is π: V _H3 = k (−B _x・sinγ・sinδ −B _y・sinγ・sinδ＋B _z・cosγ) When the rotation angle is 3/2π: V _H4 = k (B _x・sinγ・sinδ −B _y・sinγ・sinδ＋B _z・cosγ) Here, the output voltages V _H1 and V _H3 , or V _H2 and V _H4
When calculating the average value of _the sum of
It can be extracted independently using the formula.

B _z = 1/2k・1/cosγ(V _H1 +V _H3 ) or B _z =1/2k・1/cosγ(V _H2 +V _H4 )...(4) Also, the output voltages V _H1 , V _H3 , V _H2 By finding the average value of the difference between and V _H4 and organizing it, we get the following formula.

B _x・cosδ＋B _y・sinδ = 1/2k・1/sinγ (V _H1 −V _H3 ) ...(5) −B _x・sinδ＋B _y・cosδ = 1/2k・1/sinγ (V _H2 and V _H4 ...(6) Therefore, B _x and B _y can be determined separately from equations (5) and (6). That is, B _x can be obtained by the following equation from the calculation of equation (5) x cos δ - equation (6) x sin δ.

B _x = 1/2k・1/sinγ[(V _H1 −V _H3 )cosδ −(V _H2 −V _H4 )sinδ] …(7) Similarly, equation (5)×sinδ−(6)× From the calculation of cosδ, B _y can be determined using the following formula.

B _y = 1/2k・1/sin γ [(V _H2 − V _H4 ) cos δ + (V _H1 − V _H3 )] …(8) As mentioned above, the inclination angles γ and δ of the sensor 17 are actually measured in advance. Then, the three components of the magnetic field B _x , B _y ,
B _z is the actual measured output voltage V _H1 , V _H2 , V _H3 , V _H4
can be separated and extracted based on equations (7), (8), and (4), respectively. At this time, the inclination angles γ and δ can be easily measured using Helmholtz coils.

Note that among the inclination angles γ and δ, equation (4), equation (7),
It is a necessary and sufficient condition that the inclination angle γ giving the denominator of equation (8) is not 0, π/2, or π. Also, γ=45°,
At 135°, sensor 1
7 have the same sensitivity. Furthermore, n=0, 1,
2, . . . If the inclination angle δ is adjusted to δ=nπ/2, the above equations become simpler.

Thus, in order to determine the three components B _x , B _y , and B _z of the magnetic field using the measuring apparatus shown in FIGS. 1 and 2,
The measurements are carried out in the following order:

First, the sensor 17 built into the probe 16 is connected to the axis of the probe 16 (corresponding to the Z _{and M} axes).
is arranged to be inclined at a predetermined angle γ with respect to the
Also, a Helmholtz coil or the like with a known predetermined angle γ is used. Then, attach such a probe 16 to the probe fixture 15, and
The axis of the probe 16 is adjusted by the stage 19 so that it coincides with the rotation axis _ZM of the turntable 12. Note that this procedure can be simplified if the probe 16 has a positioning part that regulates the mounting angle. In any case, the angles γ and δ are constants that need only be calibrated once as a measuring device. On the other hand, the angle δ, which is the mounting angle of the probe 16, is measured using a Helmholtz coil or the like. Furthermore, probe 1
6 adjusts the rotation axis _ZM to a predetermined height position.

Next, attach the deflection yoke device 1 to the deflection yoke fixture 1.
Fixed at 4. At this time, the X, Y, and Z axes set on the deflection yoke device 1 are made to coincide with each axis direction of the measuring device. Next, the Z-axis is adjusted by the XY stage 13 so that the sensor 17 faces the desired measurement point.

Next, a magnetic field generating means (not shown) is energized to cause the deflection yoke device 1 to generate a rated magnetic field.

In this state, the turntable 12 is rotated by 90 degrees, and the output voltages V _H1 to V _H4 from the sensor 17 for each measurement angle are sequentially measured.

Next, each output voltage V _H1 obtained by the above
~V _H4 is substituted into equations (7), (8), and (4) to calculate the three components B _x , B _y , and B _z of the magnetic field.

In this way, the three components of the magnetic field at a certain predetermined measurement point were measured and calculated, but when measuring the three components of the magnetic field at other measurement points, first, the XY stage 13 is used to move the deflection yoke device 1 , set a new Z axis, and set the position of the desired measurement point in the X and Y axis directions. Furthermore, by moving the movable portion 15B of the probe fixture 15 in the Z-axis direction, the position of the sensor 17 in the Z-axis direction is set, and a desired measurement point is newly set.

Then, in the same way as the measurement method described above, the turntable 12 is rotated by 90 degrees, and the output voltage V _H1 from the sensor 17 at the newly set measurement point is measured.
V _H2 can be sequentially measured and calculated by separating the three magnetic field components based on equations (4), (7), and (8). Therefore, even if the object to be measured has a shape such as the deflection yoke device 1 or a solenoid, magnetic field measurement in detail can be easily performed by inserting the probe 16 inside and setting the desired measurement point. can be done.

Thus, by using the measuring device according to this embodiment, the three-dimensional magnetic field distribution of the entire deflection yoke device 1 can be measured with high precision. Moreover, since the output voltages V _H1 to V _H4 are measured values and the inclination angles γ and δ of the sensor 17 are known values, the measurement results are subject to errors due to the inclination of the sensor, as in the prior art. There is no need to consider factors.

In addition, since one sensor 17 is arranged inside the probe 16 at an angle, the shape of the probe 16 can be made smaller by reducing the radial dimension, and it can be brought closer to the deflection yoke device 1. Therefore, the magnetic field distribution in the details can be easily measured.

Furthermore, once it is attached to the probe fixture 15 of the probe 16, there is no need to replace it, so it is possible to significantly reduce the work required to replace and adjust the probe as in the prior art, and it is also possible to automate the measurement. .

The above describes the three components of the magnetic field (B _x ,
B _y , B _z ), but next we will discuss the case of determining the three magnetic field components (B _r , B〓, B _z ) using a cylindrical coordinate system as the second three-component magnetic field separation method. .

First, as shown in FIGS. 8 and 9, from the _ZM axis of the coordinate system of the deflection yoke device 1, the center P (γ, θ, r) of the magnetically sensitive part 17A of the sensor 17 has a radius r.
The extension of the straight line drawn by becomes the base line of the local coordinate system. The direction of this baseline is radial from the Z _M axis, and is uniquely determined as the fundamental vector 〓 _r . Further, the direction of the fundamental vector 〓θ is taken in the direction of each rotation θ as defined. Note that the direction of the fundamental vector e _z does not change.

Here, if the angle between the fundamental vector 〓 _z and the unit normal vector 〓 is γ (see Figure 8), then n _z =
becomes cosγ. Also, if _the projection vector obtained by projecting the unit normal vector 〓 onto the Z plane _is 〓
sinγ・sinφ. Note that the angle φ is the angle from the base line of the local coordinate system (the direction of the fundamental vector 〓 _r ) to the projection vector 〓 _xy . Therefore, in the cylindrical coordinate system, the unit normal vector 〓 is given by the following equation (9).

〓=sinγ・cosφ〓 _r +sinγ・sinφ〓〓〓+cosγ〓 _z ……(9) On the other hand, the magnetic flux density at the origin O is expressed as 〓=B _r 〓 _r +B〓〓〓+B _z 〓 _z ……(10) Then, the output voltage V _H of the sensor 17 is given by the following equation.

_{V. _ _} Then, it can be seen that there is a correspondence relationship between the cylindrical coordinate system and the rectangular coordinate system as follows: B _r ←→B _x B〓←→B _y φ←→δ ……(12). Therefore, the three components B _r , B〓, and B _z of the magnetic field can be easily obtained by replacing the aforementioned equations (7), (8), and (4) with equation (12).
That is, each component B _r , B〓, B _z is expressed as follows.

B _r =1/2k・1/sinγ[(V _H1 −V _H3 )cosφ −(V _H2 −V _H4 )sinφ] ……(13) B〓=1/2k・1/sinγ[(V _H2 −V _H4 )cosφ −(V _H1 −V _H3 )sinφ] …(14) B _z = 1/2k・1/cosγ(V _H1 +V _H3 ) or B _z =1/2k・1/cosγ(V _H2 +V _H4 ) ...(15) Each component of the magnetic field B _r when using a cylindrical coordinate system,
B〓, B _z can be obtained from the above equations (13) to (15), but in Fig. 1,
Regarding the measurement method using the measuring device shown in FIG. 2, as in the case of using the rectangular coordinate system, the output voltages V _H1 to V _H4 of the sensor 17 obtained when the deflection yoke device 1 is rotated by 90 degrees are Just measure it.

Here, when using a cylindrical coordinate system, the deflection device 1
The Z-axis of always lies on the _XM or _YM axis of the measuring device. Therefore, the difference in the position of the turntable 12 during measurement between the rectangular coordinate system and the cylindrical coordinate system is such that the phase is always shifted by the angle θ (=arc tany/x).

In addition, as is clear from Figure 10, the coordinate transformation between the rectangular coordinate system and the cylindrical coordinate system is as follows (16)
It is sufficient to use the coordinate transformation formula shown in the following equation, and which coordinate system to use can be freely selected for measurement and analysis.

B _x = B _r cosθ−B〓sinθ B _y = B _r sinθ−B〓cosθ B _z = B _z (common to both coordinate systems) x=rcosθ y=rsinθ x ² +y ² = r ² ……(16) Next FIG. 11 shows a second embodiment of the present invention, and the feature of this embodiment is that a deflection yoke device as an object to be detected is disposed on the rotation axis (Z _M axis) for the deflection yoke device, This is a case where the probe is placed on another axis (Z axis) parallel to the Z _M axis.

That is, in FIG. 11, the same components as those of the measuring device used in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted. In this embodiment, the axis Z _M
A turntable 22 is provided with a rotating shaft 21 having a rotation axis 21, and a deflection yoke fixture 24 is fixed vertically onto the turntable 22 with its central axis aligned with the _ZM axis. Note that in the case of this embodiment, the XY stage 13 used in the first embodiment is not necessarily required, and is therefore omitted.

Although the present embodiment is constructed as described above, there is no substantial difference in the measurement method using this measuring device from that of the first embodiment. That is, when the deflection yoke device 1 is rotated by 90 degrees by the turntable 22, the output voltages V _H1 to V _H4 obtained from the sensor 17 are measured. Then, each component of the magnetic field B _x , B _y , B _z when using a rectangular coordinate system
is calculated using formulas (7), (8), and (4), and each component of the magnetic field B _r , B〓, and B _z when using a cylindrical coordinate system is
It is calculated using formulas (13), (14), and (15).

Next, FIG. 12 shows a third embodiment of the present invention, and the feature of this embodiment is that the deflection object to be detected is placed on the axis (Z _M axis) of the deflection yoke fixture vertically erected on the XY stage. This is a case where a yoke device is provided and a probe is rotatably provided on another axis (Z axis) parallel to the _ZM axis.

That is, in FIG. 12, the same components as those of the measuring device used in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted. 31 is rotated by a motor (not shown). Among the other rotating shafts, the rotational axis of this rotating shaft 21 is the Z line. 3
2 is another turntable provided on the rotating shaft 31; 33 is another XY stage provided on the turntable 32; on the XY stage 33 there is a probe fixture 3 for fixing the probe 16;
4 is fixed, and the probe 16 is attached to the fixture 34. Then, the axis of the probe 16 is adjusted by the XY stage 33 so that it coincides with the Z axis.

Here, the deflection yoke device 1 is an XY stage 13
It is fixed to the upper deflection yoke fixture 14. Therefore, the axis of the deflection yoke device 1 coincides with the axis of the deflection yoke fixture 14 ( _ZM axis). Also,
The probe 16 is arranged so that the axis of the probe 16 is on the Z axis, which is parallel to the _ZM axis. Note that the _ZM axis in this embodiment does not mean the rotational axis of the rotating shaft 11, but the axis of the deflection yoke fixture 14, that is, the axis of the deflection yoke device 1. _{The M} axis is made variable by the XY stage 13, and measurement points are set.

The measuring device used in this example is configured in this way, but the deflection yoke device 1 is arranged on the Z _{and M} axes,
Even when the probe 16 is placed on the Z-axis, the three-component magnetic field separation method for separating the three components of the magnetic field is based on the calculation formula using the rectangular coordinate system according to the first embodiment.
Equations (7), (8), (4), or calculation formulas using cylindrical coordinate system
Equations (13), (14), and (15) can be applied as they are.

Next, the measurement order according to this embodiment will be described.

First, the probe 16 is attached to the probe fixture 34, and the axis of the probe 16 is attached to the turntable 34.
Adjust so that it matches the rotation axis Z.

Next, attach the deflection yoke device 1 to the deflection yoke fixture 1.
4, and adjust the Z _{and M} axes using the XY stage 13 so that the sensor 17 faces the desired measurement point.

In this state, the magnetic field generating means is energized, the other turntables 32 are rotated by 90 degrees, and the output voltages V _H1 to V _H4 from the sensor 17 at a certain measurement point are sequentially measured. Note that when measuring other measurement points, the deflection yoke device 1 may be moved to a desired position using the XY stage 13.

Note that in the case of this embodiment, the rotating shaft 11 and the turntable 12 are not necessarily required, and only the XY stage 13 may be used.

In each of the embodiments of the present invention, the deflection yoke device 1 is used as an example of the object to be detected, but it can be used to measure the three-dimensional magnetic field distribution of various electromagnetic devices such as transformers and solenoid coils. Also, probe 1
6 is not limited to a cylindrical shape, but can have any shape. Furthermore, as a three-component separation method of the magnetic field, the rectangular coordinate system,
Of course, the coordinate system is not limited to the cylindrical coordinate system, and a polar coordinate system may also be used. Furthermore, two parallel axes,
Although the Z _M axis and the Z axis are illustrated as being separated from each other, the Z _M axis and the Z axis may be made to coincide,
The point is that they may be spaced apart or coincident depending on the shape of the object to be detected.

〔Effect of the invention〕

As detailed above, according to the magnetic field measurement method according to the present invention, a single sensor is arranged in the probe at an angle with respect to the axis, and one of the probe or the object to be measured is rotated by 90 degrees. Since the sensor is configured to measure the magnetic field, four magnetic field measurement signals are obtained from the sensor, and the three components of the magnetic field can be easily calculated from these signals. Furthermore, since a single sensor is disposed in the probe at an angle, the probe can be made compact with small radial dimensions, making it easy to measure the magnetic field in the details of the object to be measured. is possible. Further, once the probe is set, there is no need to replace it, which can reduce the replacement work and also make it possible to automate the measurement.

[Brief explanation of drawings]

1 to 10 relate to a first embodiment of the present invention, in which FIG. 1 is a front view of the measuring device, FIG. 2 is a plan view in the direction indicated by the - arrow in FIG. A perspective view showing the mounting angle of the sensor, FIG. 4 is an explanatory diagram showing the relationship between the rectangular coordinate system and the cylindrical coordinate system,
Figure 5 is a plan view of Figure 4, Figure 6 is an explanatory diagram showing the relationship between a magnetic field and a unit normal vector when measuring three components of a magnetic field in a rectangular coordinate system, and Figure 7 is a magnetic field in a rectangular coordinate system. Figure 8 is an explanatory diagram showing the relationship between the fundamental vector and the unit normal vector when measuring the three components of the magnetic field using a cylindrical coordinate system. Figure 9 is an explanatory diagram showing the separation method of the magnetic field using the cylindrical coordinate system. 3
Fig. 10 is an explanatory diagram showing the relationship between global coordinates and local coordinates when measuring components;
The figure is a front view of the measuring device used in the second embodiment of the present invention, FIG. 12 is a front view of the measuring device used in the third embodiment of the present invention, and FIGS. 13 and 14 are related to the prior art. , FIG. 13 is an explanatory diagram showing a magnetic field measuring method using two uniaxial probes, and FIG. 14 is an explanatory diagram showing a magnetic field measuring method using one biaxial probe. 2...Deflection yoke device (object to be measured), 11,2
1, 31... Rotating axis, 12, 22, 32... Turntable, 13, 19, 33... XY stage, 16... Probe, 17... Sensor.

Claims (1)

[Claims] 1. A probe having a single sensor tilted at a predetermined angle (excluding 0, π/2, and π) with respect to the axis on one axis or an object to be measured is disposed. and placing the other of the probe or the object to be measured on the other axis parallel to the one axis (including cases where one axis and the other axis coincide), and
Based on four signals output from the probe when either the probe or the object to be measured is rotated by 90 degrees around one axis among the one axis and the other axis. , a magnetic field measuring method in which three components of the magnetic field of the object to be measured are determined separately. 2. The magnetic field measuring method according to claim 1, wherein the three components of the magnetic field are determined separately using a rectangular coordinate system. 3. The magnetic field measuring method according to claim 1, wherein the three components of the magnetic field are determined separately using a cylindrical coordinate system.