JP2015075465A - Three-dimensional magnetic field measuring apparatus and three-dimensional magnetic field measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional magnetic field measuring apparatus and a three-dimensional magnetic field measuring method capable of solving a problem of cross-axis sensitivity that constitutes a serious obstacle for realizing three-dimensional magnetic field measurement.SOLUTION: A three-dimensional magnetic field measuring apparatus 10 of the present invention is configured so that a plurality of magnetic detection elements 3 is arranged around a magnetic body 2 provided on a semiconductor IC substrate 1 and having a magnetic amplification function. A signal processing unit 12 generates output signals Vsig,x, Vsig,y, and Vsig,z that are three-dimensional vector signals corresponding to three-dimensional magnetic vectors Hx, Hy, and Hz input to the magnetic body 2, respectively. A correction-coefficient storage unit 14 stores a correction coefficient for correcting cross-axis sensitivity generated in magnetic-electric conversion performed by the signal processing unit 12 for generating the three-dimensional output signals Vsig,x, Vsig,y, and Vsig,z. A magnetic-field-component calculation unit 15 calculates the three-dimensional output signals Vsig,x, Vsig,y, and Vsig,z based on the correction coefficient stored in the correction-coefficient storage unit 14.

Description

  The present invention relates to a three-dimensional magnetic field measurement apparatus and a three-dimensional magnetic field measurement method, and more particularly to a three-dimensional magnetic field measurement apparatus that performs three-dimensional (three-axis) magnetic field measurement and a measurement method thereof. In particular, the present invention is applicable to an electronic compass, a three-dimensional rotation angle sensor, and the like regarding a correction technique for other-axis sensitivity when measuring the magnetic field of each component of the X-axis, Y-axis, and Z-axis into an electric signal.

Conventionally, as a magnetic field measuring apparatus, a Hall element provided on a semiconductor substrate and a magnetic body (magnetic focusing plate) having a magnetic focusing function provided on the Hall element are magnetically focused on the Hall element. It is well known to measure the magnetic field strength with a Hall element.
Magnetic field measuring devices that measure magnetic fields (three-dimensional magnetic field vectors) to be measured using magnetic detection elements such as Hall elements and MR elements (magnetoresistance elements) are made of those magnetic detection elements and magnetic materials. Many are realized by the structure which combined the magnetic convergence board (for example, refer patent document 1 and 2, patent document 5).

For example, Patent Documents 1 and 2 disclose the structure of a magnetic field measuring apparatus in which a Hall element paired with a position near the outer periphery of a magnetic focusing plate is arranged.
Patent Document 5 discloses a three-dimensional magnetic field measuring apparatus that measures a three-dimensional magnetic field using a GMR (Giant Magneto Resistive Effect) element. By combining these, three-dimensional magnetic field measurement is realized.

  Among such magnetic field measuring devices, a semiconductor manufacturing process is used to form a plurality of Hall elements (silicon monolithic Hall elements) in a silicon IC substrate, and a magnetic convergence plate is formed on the silicon IC substrate. The structure of the magnetic field measurement device can be measured by converting the magnetic field to be measured into a space vector (three-dimensional vector) as an electric signal (see, for example, Patent Documents 1 and 2).

For this reason, the structure of this magnetic field measuring apparatus is used in applications such as a geomagnetic sensor (electronic compass) that measures a spatial component of geomagnetism as a three-dimensional vector.
As described above, the structure of the magnetic field measuring device in which the magnetic converging plate is arranged on the silicon semiconductor IC including the plurality of silicon monolithic Hall elements and the plurality of silicon monolithic Hall elements has a spatial component of geomagnetism as a three-dimensional vector. Regarding the three-dimensional magnetic field measuring device to be measured, the structure of the magnetic field measuring device is extremely suitable.

Patent Document 3 discloses a structure of a magnetic field measuring device in which a magnetic focusing plate is formed on a semiconductor substrate having a Hall element built therein. In addition, regarding the structure of the magnetic field measurement device which is the premise of the three-dimensional magnetic field measurement device of the present invention, details of its shape, various manufacturing methods, various constituent materials, and the like are disclosed.
Patent Document 4 discloses signal processing means for measuring a three-dimensional vector signal based on output signals from a plurality of sensor elements in an application such as an electronic compass for measuring a three-dimensional magnetic field. Yes.

  Patent Document 5 discloses a three-dimensional magnetic field measuring apparatus that measures a three-dimensional magnetic field using a GMR element. The three-dimensional magnetic field measuring apparatus described in Patent Document 5 realizes a three-dimensional magnetic field measurement by combining a GMR element and a magnetic focusing plate formed using a soft magnetic material. In the three-dimensional magnetic field measuring apparatus disclosed in Patent Document 5, since the GMR element is a magnetoelectric conversion element that measures a magnetic field component that is horizontal to the GMR element, the magnetic convergence from the magnetic field component perpendicular to the magnetic convergence plate. A magnetic converging plate is used for the purpose of obtaining a magnetic flux horizontal to the plate. On the other hand, in the structure of the magnetic field measuring apparatus using the Hall element, which is the premise of the present invention, the Hall element is a magnetoelectric conversion that measures a magnetic field component perpendicular to the Hall element. The magnetic converging plate is used for the purpose of obtaining a magnetic flux perpendicular to the magnetic converging plate.

  Further, in Patent Document 6, in relation to an azimuth angle sensor (electronic compass) that measures a geomagnetic three-dimensional magnetic field, the influence of an offset magnetic field other than the geomagnetism can be canceled to measure the geomagnetic three-dimensional magnetic field. It is disclosed. The geomagnetic sensor module shown in the example of this Patent Document 6 is not particularly one having the structure of the magnetic field measuring apparatus which is the premise of the present invention, but measures each of the X, Y and Z components of the geomagnetism. Therefore, a geomagnetic sensor module incorporating three Hall elements HEEx, HEy, and HEz is provided. Further, in Patent Document 6, by measuring the signals (Hall electromotive force signals) output from the three Hall elements HEx, HEy, HEz while changing the direction of the above-described geomagnetic sensor module, the vicinity of the geomagnetic sensor module is measured. An offset correction procedure for a geomagnetic sensor module that measures an offset magnetic field that interferes with a geomagnetic sensor generated from a speaker or the like disposed in the above is disclosed.

  Further, in Patent Document 7, in relation to an azimuth angle sensor (electronic compass) that measures a geomagnetic three-dimensional magnetic field, the influence of an offset magnetic field other than the geomagnetism can be canceled to measure the geomagnetic three-dimensional magnetic field. It is disclosed. The azimuth measuring device shown in the embodiment of Patent Document 7 is not particularly the structure of the magnetic field measuring device that is the premise of the present invention, but each of the X, Y, and Z components of geomagnetism. In order to measure the azimuth angle measuring apparatus, three Hall elements HEx, HEy, and HEz are incorporated. In Patent Document 7, as in Patent Document 6 described above, the offset of the azimuth measuring device that measures an offset magnetic field that interferes with the azimuth measuring device generated from a speaker or the like disposed near the azimuth measuring device. A correction procedure is disclosed. In Patent Document 7, a geometric calculation method is used on the basis of a set of measured geomagnetic vectors, particularly when a geomagnetic vector is measured a predetermined number of times or more by an azimuth measuring device. An offset correction procedure for an azimuth angle measuring apparatus that measures an offset magnetic field is disclosed.

  Further, in Patent Document 8, when measuring the magnetic field in the horizontal direction and the vertical direction, the deviation in measurement sensitivity between the horizontal direction and the vertical direction caused by using the magnetic focusing plate is eliminated, and the vertical direction is determined. A three-dimensional magnetic measurement apparatus having an improved S / N ratio for magnetic field measurement in a direction is disclosed. That is, the problem of the magnetic sensitivity difference (difference in magnetic sensitivity between the XY plane and the Z axis) which is a problem in the structure of the magnetic field measuring apparatus using the magnetic converging plate which is the premise of the present invention is dealt with. In the structure of a magnetic field measuring apparatus using a magnetic converging plate, which is a premise of the present invention, a disk-shaped magnetic converging plate is generally used. Regarding the size and shape of the magnetic converging plate having such a shape, the diameter of the magnetic converging plate is used. Is sufficiently larger than the thickness of the magnetic converging plate, the magnetism in the Z direction (disk thickness direction) is compared with the magnetic amplification factor of the magnetic converging plate in the X direction and Y direction (in-plane direction of the disk). In response to the technical problem that the amplification factor becomes small, Patent Document 8 discloses a Hall element arrangement that solves this problem.

  Patent Document 9 discloses a three-dimensional electric field corresponding to a three-dimensional magnetic field by using a structure of a magnetic field measuring apparatus which is a premise of the present invention, that is, a structure of a magnetic field measuring apparatus in which a Hall element and a magnetic focusing plate are combined. As for the three-dimensional magnetic field measurement for obtaining a signal, a solution to a sensitivity mismatch in which the sensitivities do not match among the X-axis, Y-axis, and Z-axis is disclosed, as in Patent Document 8 described above.

  Patent Document 10 discloses a device such as a brake pedal or a shift lever by performing three-dimensional magnetic field measurement using the structure of a magnetic field measuring device using a Hall element and a magnetic converging plate, which is a premise of the present invention. A rotation angle sensor is shown which measures the rotational position at the position by non-contact means. The rotation angle sensor shown in FIG. 2 of Patent Document 10 uses the X-axis and Z-axis components in the orthogonal coordinate system shown in FIG. Although it is a rotation angle sensor for measuring (angle on the ZX plane), the Z-axis magnetic field measurement accuracy is important for the rotation angle sensor of FIG. It can be an example to do.

JP 2002-71381 A US Pat. No. 6,545,462 (B2) International Publication No. WO 2007/11969 (A1) International Publication WO 2008/032741 (A1) International Publication WO2011 / 068146 (A1) Japanese Patent Laid-Open No. 2004-12416 International Publication WO 2005/061990 (A1) Japanese Patent Laid-Open No. 2004-25795 International Publication WO 2008/123144 (A1) JP 2012-98138 A

Patent Documents 1 and 2 described above show the structure of a three-dimensional magnetic field measuring device in which a Hall element paired with a position near the outer periphery of the magnetic focusing plate is arranged. It is based on the structure of the device.
The three-dimensional magnetic field measuring device is a signal indicating the direction and magnitude of the magnetic field component in the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measuring device, and a signal indicating the direction and magnitude of the magnetic field component in the Y-axis direction. , A device that outputs a signal indicating the direction and magnitude of the magnetic field component in the Z-axis direction. The X axis direction, the Y axis direction, and the Z axis direction are directions orthogonal to each other.

However, Patent Documents 1 and 2 make no mention of the occurrence of other-axis sensitivity, means for correcting other-axis sensitivity, and the like.
Here, the other-axis sensitivity is a signal other than the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measurement device in the signal indicating the direction and magnitude of the magnetic field component in the X-axis direction output from the three-dimensional magnetic field measurement device. That is, a signal component corresponding to the axial magnetic field component is included.

The other-axis sensitivity component is the X-axis of the magnetic field applied to the three-dimensional magnetic field measurement device included in the signal indicating the direction and magnitude of the magnetic field component in the X-axis direction output from the three-dimensional magnetic field measurement device. A signal component corresponding to a magnetic field component in an axial direction other than the direction.
In the above description, the other-axis sensitivity and the other-axis sensitivity component have been described with the X-axis direction as the center.

  Further, Patent Document 3 shows the structure of a magnetic field measuring device in which a magnetic focusing plate is formed on a semiconductor substrate with a built-in Hall element. The shape of the side surface of the magnetic focusing plate is tapered. Although there is a description about the advantage, in the case of the magnetic converging plate having this tapered side surface, a magnetic sensitivity mismatch is likely to occur between two Hall elements arranged at both ends of the diameter of the disk-shaped magnetic converging plate. . As can be seen from this, the structure of the magnetic field measuring apparatus using the magnetic focusing plate described in Patent Document 3 is a magnetic field measuring apparatus that is liable to cause a problem of other-axis sensitivity that is a problem to be solved by the present invention. It can be said that it is a structure. That is, Patent Document 3 does not mention anything about the occurrence of other-axis sensitivity, means for correcting the other-axis sensitivity, and the like.

  Patent Document 4 describes a signal processing means for measuring a three-dimensional vector signal based on output signals from a plurality of sensor elements in an application such as an electronic compass for measuring a three-dimensional magnetic field. Yes. That is, in the signal processing means for measuring the three-dimensional vector signal, a signal obtained by linear combination of the X component, the Y component, and the Z component of the three-dimensional vector signal can be measured. The signal detection using this linear combination realizes a three-dimensional physical quantity measuring means for improving the S / N ratio obtained within a predetermined measurement time. However, this Patent Document 4 is exclusively related to the S / N ratio in three-dimensional physical quantity measurement, and does not mention any means for correcting other-axis sensitivity in the detected three-dimensional vector signal.

Patent Document 5 discloses a structure of a magnetic field measuring apparatus that measures a three-dimensional magnetic field using a GMR element and a magnetic converging plate. However, a magnetic field measuring apparatus using the GMR element and the magnetic converging plate is disclosed. No mention is made of the generation of other-axis sensitivity and the means for correcting the other-axis sensitivity with respect to the structure of the above and the structure of the magnetic field measuring apparatus using the Hall element and the magnetic converging plate.
In Patent Documents 6 and 7, the influence of an offset magnetic field other than geomagnetism is canceled and the geomagnetic three-dimensional magnetic field is measured in relation to an azimuth angle sensor (electronic compass) that measures the geomagnetic three-dimensional magnetic field. Although the technology is described, regarding the structure of this magnetic field measuring apparatus, an alignment error occurs between the Hall element formed in the silicon IC substrate and the magnetic focusing plate formed on the silicon IC substrate. When measuring a three-dimensional magnetic field vector, there is a weak point that other-axis sensitivity occurs between three spatial components. As a result, the three-dimensional magnetic field measurement using the structure of the magnetic field measurement apparatus has a problem that the magnetic field measurement accuracy is greatly deteriorated in applications such as a geomagnetic sensor due to the presence of this weak point.

In addition, in the three-dimensional magnetic field measurement using a magnetic converging plate as performed by an electronic compass, other axis sensitivities occur in the X-axis-Z-axis and Y-axis-Z-axis with respect to the Z-axis magnetic field measurement. There was a problem that it was easy.
In other words, improvement of the magnetic field measurement accuracy in the three-dimensional magnetic field measurement device using the magnetic focusing plates of Patent Documents 1 and 2 described above is an issue, and in the structure of the magnetic field measurement device described above, the magnetic focusing plate and the Hall element are Correction of other-axis sensitivity (other-axis sensitivity between the XYZ axes) that is likely to occur when the relative position between them is shifted is a problem.

  Moreover, in the three-dimensional magnetic measurement apparatus described in Patent Document 8, one solution is disclosed for the technical problem of the difference in magnetic sensitivity between the Z-axis direction and the X-axis and Y-axis directions. is there. On the other hand, the technical problem to be solved by the present invention is that, in a three-dimensional magnetic field measuring apparatus that generates a three-dimensional electric signal from a three-dimensional magnetic field measurement, among the electric signals corresponding to the Z-axis magnetic field, This is a so-called other-axis sensitivity problem in which a component of an electric signal corresponding to the Y-axis magnetic field is mixed. There is no description in Patent Document 8 regarding the problem of other-axis sensitivity in this three-dimensional magnetic field measuring apparatus.

Further, the solving means shown in Patent Document 9 forms a correction coil between the Hall element and the magnetic converging plate, and uses the magnetic field generated by this coil to make the X, Y and Z axes. The magnetic sensitivity mismatch is corrected. However, this Patent Document 9 also has no description regarding correction of other-axis sensitivity between three-dimensional components.
In addition, as for the devices such as the brake pedal and the shift lever listed in Patent Document 10, the brake pedal is similar to the geomagnetic sensor in that the basic technology is based on the three-dimensional magnetic field measurement. The angle measurement accuracy required in devices such as a shift lever and a shift lever is generally required to be much stricter than the angle measurement accuracy required in a geomagnetic sensor. As can be understood from the above, in order to realize a device such as a brake pedal and a shift lever with high accuracy using the technique disclosed in Patent Document 10, 3 shown in FIG. It is necessary that the three-dimensional magnetic field measurement apparatus realizes highly accurate three-dimensional magnetic field measurement. Therefore, the present invention that enables the realization of a highly accurate three-dimensional magnetic field measuring apparatus is an indispensable technique for realizing the rotation angle sensor described in Patent Document 10.

  The present invention has been made in view of such a situation, and an object of the present invention is to solve the problem of other-axis sensitivity that becomes a serious obstacle to realizing highly accurate three-dimensional magnetic field measurement. Another object of the present invention is to provide a three-dimensional magnetic field measuring apparatus and a three-dimensional magnetic field measuring method.

  The present invention has been made in order to achieve such an object, and the invention according to claim 1 includes a magnetic body (2) and a first to a second body disposed in the vicinity of the magnetic body (2). A magnetic field applied to the three-dimensional magnetic field measurement device (10) based on output signals of the first to fourth magnetic detection elements. Stores a calculation unit (12) that generates an output signal (Vsig, x, Vsig, y, Vsig, z) according to, and a correction coefficient for correcting the other-axis sensitivity component included in the output signal of the calculation unit A correction coefficient storage unit (14) that performs, a magnetic field component in the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measurement device (10) based on the output signal of the calculation unit and the correction coefficient, and the X axis A magnetic field component in the Y-axis direction orthogonal to the direction, the X-axis direction, and Comprising calculation unit for calculating the magnetic field component in the Z-axis direction perpendicular to the axial direction (15), the.

  According to a second aspect of the present invention, in the first aspect of the present invention, the arithmetic unit is configured to output the output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the second magnetic field. The output signal (Vsig (HallX2)) of the detection element (3X2) is input, and the output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the output of the second magnetic detection element (3X2). A first signal processing unit (12x) that outputs a signal (Vsig, x) based on a difference or sum of signals (Vsig (HallX2)), and an output signal (Vsig (HallY1) of the third magnetic detection element (3Y1) )) And the output signal (Vsig (HallY2)) of the fourth magnetic detection element (3Y2), and the output signal (Vsig (HallY1) of the third magnetic detection element (3Y1). )) And a fourth signal processing unit (12y) for outputting a signal (Vsig, y) based on the difference or sum of the output signals (Vsig (HallY2)) of the fourth magnetic detection element (3Y2); The output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the output signal (Vsig (HallX2)) of the second magnetic detection element (3X2) are input, and the first magnetic detection element (3X1) ) Output signal (Vsig (HallX1)) and the output signal (Vsig (HallX2)) of the second magnetic detection element (3X2), the first signal processing unit (12x) And a third signal processing unit (12z) that outputs a different signal (Vsig, z).

  According to a third aspect of the present invention, there is provided a magnetic body (2), first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) disposed in the vicinity of the magnetic body (2), An output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and an output signal (Vsig (HallX2)) of the second magnetic detection element (3X2) are input, and the first magnetic detection element A first signal (Vsig, x) based on the difference or sum of the output signal (Vsig (HallX1)) of (3X1) and the output signal (Vsig (HallX2)) of the second magnetic detection element (3X2) The signal processing unit (12x), the output signal (Vsig (HallY1)) of the third magnetic detection element (3Y1), and the output signal (Vsig (HallY2)) of the fourth magnetic detection element (3Y2) are input. The signal (Vsig) based on the difference or sum of the output signal (Vsig (HallY1)) of the third magnetic detection element (3Y1) and the output signal (Vsig (HallY2)) of the fourth magnetic detection element (3Y2). , y), the second signal processing unit (12y), the output signal of the first magnetic detection element (3X1) (Vsig (HallX1)), and the output signal of the second magnetic detection element (3X2) (Vsig (HallX2)) is input, and the output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the output signal (Vsig (HallX2)) of the second magnetic detection element (3X2) A third signal processing unit (12z) that outputs a signal (Vsig, z) different from the first signal processing unit (12x), which is a signal based on a sum or difference, and the first to third signals. A correction coefficient storage unit (14) for storing correction coefficients for correcting output signals (Vsig, x, Vsig, y, Vsig, z) of the processing units (12x to 12z), and the first to third signals. Based on the output signals (Vsig, x, Vsig, y, Vsig, z) of the processing unit (12x to 12z) and the correction coefficient, the magnetic field component in the X-axis direction and the magnetic field in the Y-axis direction orthogonal to the X-axis direction And a magnetic field component calculation unit (15) that calculates a magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction.

  According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the value indicated by the signal output from the first signal processing unit (12x) is Vsig, x, and the second signal processing. When the value output by the signal output from the unit (12y) is Vsig, y and the value output by the signal output from the third signal processing unit (12z) is Vsig, z, the correction coefficient is a three-dimensional vector. This is a coefficient for converting the signal (Vsig, x, Vsig, y, Vsig, z) into another three-dimensional vector signal (Sx, Sy, Sz).

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the correction coefficient is obtained by changing the first magnetic field, the second magnetic field, and the third magnetic field to the three-dimensional magnetic field. Calculation based on output signals (Vsig (HallX1) to Vsig (HallY2)) output from the first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) when applied to the measuring device (10). Is a coefficient.

According to a sixth aspect of the invention, in the fifth aspect of the invention, the first magnetic field, the second magnetic field, and the third magnetic field are linearly independent magnetic fields.
The invention according to claim 7 is the invention according to claim 5 or 6, wherein the three orthogonal directions are defined as an X′-axis direction, a Y′-axis direction, and a Z′-axis direction, respectively. The first magnetic field is a magnetic field having a magnetic field component in the X′-axis direction and having very little magnetic field component in the Y′-axis direction and a magnetic field component in the Z′-axis direction, and the second magnetic field is in the Y′-axis direction. The third magnetic field has a magnetic field component in the Z′-axis direction, and has a magnetic field component in the X′-axis direction and a magnetic field component in the Z′-axis direction. The magnetic field component of the direction and the magnetic field component of the Y′-axis direction are extremely small.
The invention according to claim 8 is the invention according to claim 7, wherein the X-axis direction and the X′-axis direction are the same direction, and the Y-axis direction and the Y′-axis direction are the same direction. Yes, the Z-axis direction and the Z′-axis direction are the same direction.

  The invention according to claim 9 is the invention according to any one of claims 5 to 8, wherein the correction coefficient is applied when the first magnetic field is applied to the three-dimensional magnetic field measuring apparatus (10). A value based on a signal (Vsig, x) output from the first signal processing unit (12x) is α1 (Dxx in Expression 17), and the first magnetic field is applied to the three-dimensional magnetic field measuring apparatus (10). Sometimes the value based on the signal (Vsig, z) output from the third signal processing unit (12z) is α2 (NDzx in Expression 17), and the second magnetic field is supplied to the three-dimensional magnetic field measuring apparatus (10). A value based on the signal (Vsig, y) output from the second signal processing unit (12y) when applied is β1 (Dyy in Expression 17), and the second magnetic field is the three-dimensional magnetic field measuring device (10 ) When applied to the third signal processing unit (1). z) is a value based on the signal (Vsig, z) output from β2 (NDzv in Expression 17), and the third signal is applied to the three-dimensional magnetic field measuring apparatus (10). When the value based on the signal (Vsig, x) output from the unit (12x) is γ1 (NDxz in Expression 17) and the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus (10), the second A value based on the signal (Vsig, y) output from the signal processing unit (12y) is γ2 (NDyz in Expression 17), and the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus (10). 3 based on α1, α2, β1, β2, γ1, γ2, and γ3, where γ3 (Dzz in Equation 17) is a value based on the signal (Vsig, z) output from the signal processing unit (12z) 3 Value.

Further, the invention according to claim 10 is the invention according to any one of claims 2 to 9,
The third signal processing unit (12z) receives the output signals of the first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2), and the first to fourth magnetic detection elements (3X1). , 3X2, 3Y1, 3Y2) are output based on the sum or difference of the output signals.
According to an eleventh aspect of the present invention, in the invention according to the third aspect, the magnetic field component calculation unit (15) outputs an output signal (Vsig) of the first to third signal processing units (12x to 12z). , x, Vsig, y, Vsig, z) and the correction coefficient, an X-axis direction magnetic field component calculation unit (15x) that calculates a magnetic field component in the X-axis direction, and the first to third signal processing units ( 12x to 12z) based on the output signals (Vsig, x, Vsig, y, Vsig, z) and the correction coefficient, a Y-axis direction magnetic field component calculation unit (15y) that calculates a magnetic field component in the Y-axis direction, A Z-axis direction magnetic field component for calculating a Z-axis direction magnetic field component based on the output signals (Vsig, x, Vsig, y, Vsig, z) of the first to third signal processing units (12x to 12z) and the correction coefficient And a calculation unit (15z).

  According to a twelfth aspect of the present invention, in the semiconductor device according to any one of the first to eleventh aspects, the first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) are arranged. An IC substrate (1) is provided, and the first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) include the first magnetic detection element (3X1) and the second magnetic detection element (3X2). And a straight line connecting the third magnetic detection element (3Y1) and the fourth magnetic detection element (3Y2) are arranged so as to be substantially orthogonal to each other.

According to a thirteenth aspect of the present invention, in the twelfth aspect of the present invention, a direction of a straight line from the first magnetic detection element (3X1) to the second magnetic detection element (3X2), and the X The axial directions are the same, and the direction of the straight line from the third magnetic detection element (3Y1) to the fourth magnetic detection element (3Y2) is the same as the Y-axis direction.
The invention according to claim 14 is the invention according to any one of claims 1 to 13, wherein the first to fourth magnetic detection elements are configured to detect each magnetic field when the magnetic body is viewed in plan view. At least a part of the magnetic sensing portion of the element is disposed at a position covered with the magnetic body.

The invention according to claim 15 is the invention according to any one of claims 1 to 14, wherein the magnetic substance has a circular shape or a polygonal shape.
The invention according to claim 16 is the invention according to any one of claims 1 to 15, wherein the magnetic body has a point-symmetric shape, and when the magnetic body is viewed in plan, the first The position of the midpoint of the line segment connecting the first magnetic detection element and the second magnetic detection element is different from the position of the symmetry point of the magnetic body.

The invention according to claim 17 is the invention according to any one of claims 1 to 16, wherein the magnetic sensitivity of the first magnetic detection element is different from the magnetic sensitivity of the second magnetic detection element.
The invention according to claim 18 is the invention according to any one of claims 1 to 17, wherein the magnetic body of the magnetic sensing portion of the first magnetic detection element when the magnetic body is viewed in plan. The area of the portion covered with the magnetic material is different from the area of the portion covered with the magnetic body of the magnetic sensing portion of the second magnetic detection element.

According to a nineteenth aspect of the present invention, in the invention according to any one of the first to eighteenth aspects, the magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) are Hall elements.
According to a twentieth aspect of the present invention, there is provided a three-dimensional magnetic field measuring apparatus (10) comprising: a magnetic body (2); and first to fourth magnetic detection elements disposed in the vicinity of the magnetic body (2). ) Using the output signals of the first to fourth magnetic sensing elements based on the magnetic field applied to the three-dimensional magnetic field measuring device (10) ( Vsig, x, Vsig, y, Vsig, z), a correction coefficient storage step for storing a correction coefficient for correcting the other-axis sensitivity component included in the signal generated in the calculation step, The magnetic field component in the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measuring device (10) based on the signal generated in the calculation step and the correction coefficient, and the Y-axis direction orthogonal to the X-axis direction. Magnetic field component, X-axis direction and Y Having a calculation step of calculating the Z-axis direction of the magnetic field component perpendicular to the direction.

  The invention according to claim 21 is the magnetic body (2), the first to fourth magnetic detection elements (3X1, 3X2, 3Y1, 3Y2) disposed in the vicinity of the magnetic body (2), A three-dimensional magnetic field measurement method using a three-dimensional magnetic field measurement apparatus (10) comprising: an output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the second magnetic detection element ( 3X2) output signal (Vsig (HallX2)) is input, and the output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the output signal (Vsig of the second magnetic detection element (3X2)). (HallX2)), a first signal processing step that outputs a signal (Vsig, x) based on the difference or sum, an output signal (Vsig (HallY1)) of the third magnetic detection element (3Y1), and the fourth of The output signal (Vsig (HallY2)) of the magnetic detection element (3Y2) is input, and the output signal (Vsig (HallY1)) of the third magnetic detection element (3Y1) and the fourth magnetic detection element (3Y2). A second signal processing step of outputting a signal (Vsig, y) based on a difference or sum of output signals (Vsig (HallY2)), and an output signal (Vsig (HallX1)) of the first magnetic detection element (3X1); And the output signal (Vsig (HallX2)) of the second magnetic detection element (3X2), and the output signal (Vsig (HallX1)) of the first magnetic detection element (3X1) and the second magnetic detection. A signal based on the sum or difference of the output signals (Vsig (HallX2)) of the element (3X2), which is different from the first signal processing step (Vsig, z) A third signal processing step to output, and a correction coefficient storage step for storing correction coefficients for correcting the output signals (Vsig, x, Vsig, y, Vsig, z) of the first to third signal processing steps. Based on the output signals (Vsig, x, Vsig, y, Vsig, z) of the first to third signal processing steps and the correction coefficient, the magnetic field component in the X-axis direction is orthogonal to the X-axis direction. A magnetic field component calculating step of calculating a magnetic field component in the Y-axis direction and a magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction.

  According to the present invention, a three-dimensional magnetic field measuring apparatus and a three-dimensional magnetic field measurement capable of correcting the sensitivity of other axes when measuring by converting the magnetic field of each component of the X axis, Y axis, and Z axis into an electrical signal. A method can be realized. In particular, it can be applied to an electronic compass, a three-dimensional rotation angle sensor, and the like.

It is a block diagram for demonstrating the three-dimensional magnetic field measuring apparatus used as the premise of this invention. It is a figure for demonstrating the relative position between a magnetic convergence board and a Hall element. It is a figure for demonstrating magnetic flux distribution when the magnetic field of an X-axis direction is input with respect to the three-dimensional magnetic field measuring apparatus shown in FIG. It is a figure for demonstrating the mode of the magnetic force line which penetrates the position of Hall element HallX1, and the magnetic sensitive surface of Hall element HallX2, when the relative position between a magnetic focusing plate and a Hall element has shifted | deviated from the relative position which should be originally. It is a figure for demonstrating the coordinate axis of the electric signal Vsig, x, Vsig, z in the ideal case where another-axis sensitivity does not generate | occur | produce about the electric signal Vsig, x, Vsig, z corresponding to magnetic component Hx, Hz. . It is a figure for demonstrating the coordinate axis of electric signal Vsig, x, Vsig, z when another-axis sensitivity generate | occur | produces about the electric signal Vsig, x, Vsig, z corresponding to magnetic component Hx, Hz. It is a figure which shows the angle measurement error when the angle of an input magnetic field is measured in a ZX plane when there exists the other-axis sensitivity shown by FIG. It is a block diagram for demonstrating embodiment of the tertiary magnetic field measuring apparatus which concerns on this invention. It is a figure which shows the flowchart of the correction procedure in the magnetic field measuring method of the three-dimensional magnetic field measuring apparatus which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a three-dimensional magnetic field measuring apparatus which is a premise of the present invention will be described below.
FIG. 1 is a configuration diagram for explaining a three-dimensional magnetic field measuring apparatus which is a premise of the present invention. In the figure, reference numeral 1 is a semiconductor IC substrate (CMOSIC), 2 is a magnetic body (magnetic converging plate), 3 (3X1, 3X2, 3Y1, 3Y2) is a magnetic detection element (silicon monolithic Hall element), and 10 is a three-dimensional magnetic field measuring device. Is shown. In addition, orthogonal coordinate axes (X axis, Y axis, Z axis), which serve as a reference for spatial coordinates when describing a three-dimensional magnetic field vector to be measured, are shown.

The three-dimensional magnetic field measuring apparatus shown in FIG. 1 measures a three-dimensional magnetic field vector defined as (Hx, Hy, Hz) under the illustrated orthogonal coordinate system (X axis, Y axis, Z axis). Is.
The three-dimensional magnetic field measuring apparatus shown in FIG. 1 has four Hall elements 3X1 (HallX1), 3X2 formed in CMOSIC1 using a manufacturing process of CMOS (Complementary Metal Oxide Semiconductor). The disk-shaped magnetic converging plate 2 is arranged above (HallX2), 3Y1 (HallY1), and 3Y2 (HallY2).

This Hall element can measure the magnetic field component in the direction perpendicular to the chip surface of the CMOSIC 1 by using the N well as the Hall element in the CMOS IC 1.
FIG. 2 is a diagram for explaining the relative position between the magnetic flux concentrating plate and the Hall element, and is a configuration diagram of the three-dimensional magnetic field measuring apparatus shown in FIG. 1 as viewed from the upper direction of the Z axis. Reference numeral 4 in the drawing indicates the outer periphery of the magnetic flux concentrating plate. In addition, the same code | symbol is attached | subjected to the component which has the same function as FIG.

As shown in FIG. 2, the pair of Hall elements HallX1 and HallX2 are disposed on the X axis in the CMOSIC1, and the pair of Hall elements HallY1 and HallY2 are disposed on the Y axis in the CMOSIC1. Yes.
A technique for measuring a three-dimensional magnetic field (intensity) vector (Hx, Hy, Hz) using these four Hall elements HallX1, HallX2, HallY1, and HallY2 has the same configuration as that of Patent Documents 1 and 2 described above. It has become.

  In general, a material having a high magnetic permeability μ as a physical constant is used as the material of the magnetic flux concentrating plate, and a relationship represented by B = μ × H exists between the magnetic flux density B and the magnetic field strength H. Here, the magnetic flux density B and the magnetic field strength H are three-dimensional vectors (Hx, Hy, Hz) and (Bx, By, Bz), respectively. Further, in the magnetic converging plate, the magnetic permeability μ is a tensor amount on the second floor, and is expressed using a matrix of 3 rows and 3 columns.

  In FIG. 1 and FIG. 2, there is a formula (1) between the magnetic flux density B (HallX1) in the Hall element HallX1 arranged at the position of X> 0 on the X axis and the input magnetic field H to the three-dimensional magnetic field measuring device. There is a relationship described in. In Equation (1), the magnetic permeability at the position of the Hall element HallX1 is represented by a second-order tensor (matrix with 3 rows and 3 columns) M (HallX1).

  Similarly, in FIGS. 1 and 2, between the magnetic flux density B (HallX2) in the Hall element HallX2 arranged at the position of X <0 on the X axis and the input magnetic field strength H to the three-dimensional magnetic field measuring device, There is a relationship described by Equation (2). In Equation (2), the magnetic permeability at the position of the Hall element HallX2 is represented by a second-order tensor (matrix with 3 rows and 3 columns) M (HallX2).

1 and 2 showing the three-dimensional magnetic field measuring apparatus, in the two Hall elements HallX1 and HallX2 arranged on the X axis, as represented by Equation (1) and Equation (2), respectively, 3 There is a relationship between the input magnetic field strength H and the magnetic flux density B to the dimensional magnetic field measuring apparatus.
Regarding the two Hall elements HallY1 and HallY2 arranged on the Y axis of the three-dimensional magnetic field measuring apparatus, the relationship between the input magnetic field strength H and the magnetic flux density B is the same as that of the two Hall elements HallX1 and HallX2 arranged on the X axis. It is easy to understand that there is.

  Therefore, in the detailed description given in the following part, the explanation will be focused on the Hall elements HallX1 and HallX2 on the X axis, but the situation similar to the situation in the Hall elements HallX1 and HallX2 on the X axis is the Y axis. It can be easily understood that the above two Hall elements HallY1 and HallY2 are also generated. Therefore, the same applies to the two Hall elements HallY1 and HallY2 on the Y axis.

  FIG. 3 is a diagram for explaining the magnetic flux distribution when a magnetic field in the X-axis direction is input to the three-dimensional magnetic field measuring apparatus shown in FIG. 1, and when a magnetic field vector is input to the magnetic convergence plate. It is a figure which shows the mode of a magnetic flux vector. Here, in the three-dimensional magnetic field measuring apparatus of the present invention, a magnetic field vector having a non-zero component only in the X-axis direction (magnetic field vector parallel to the chip surface of CMOSIC1) is input.

Here, as understood from FIG. 3, at the position of the Hall element HallX1, the magnetic flux density Bz (HallX1) having a positive Z-axis component passes through the Hall element HallX1.
The magnetic flux density Bz (HallX1) in the Hall element HallX1 is attributed to the input magnetic field component Hx in the X-axis direction. , Can be described as Equation (3). Here, since the magnetic flux density Bz (HallX1) of the Z-axis component in the Hall element HallX1 is a plus sign, the tensor component Mzx (HallX1)> 0.

Similarly, as understood from FIG. 3, at the position of the Hall element HallX2, the magnetic flux density Bz (HallX2) having a negative Z-axis component passes through the Hall element HallX2.
The magnetic flux density Bz (HallX2) in the Hall element HallX2 is caused by the input magnetic field component Hx in the X-axis direction. , Can be described as Equation (4). Here, since the magnetic flux density Bz (HallX2) of the Z-axis component in the Hall element HallX2 is a minus sign, the tensor component Mzx (HallX2) <0.

  As described above, by arranging a Hall element in the vicinity of the outer periphery of the disk-shaped magnetic focusing plate 2 placed on the upper part of the CMOSIC, a magnetic field component parallel to the CMOSIC surface is converted into a magnetic flux perpendicular to the CMOSIC surface to generate a hole. About the form of the magnetic field measuring apparatus detected with an element, it describes in patent document 1 and 2 mentioned above.

In the above, as the structure of the magnetic field measuring apparatus as a premise of the present invention, the magnetic focusing plate 2 formed on the upper part of the CMOSIC 1 is used to convert the three-dimensional magnetic field vector (Hx, Hy, Hz) to the three-dimensional magnetic flux density vector. The generation of (Bx, By, Bz) has been described.
By arranging the Hall element at a position near the outer periphery of the magnetic focusing plate, the magnetic field in the X-axis direction and the magnetic field in the Y-direction are converted into magnetic flux (Z-axis direction magnetic flux) in a direction penetrating the magnetic sensing surface of the Hall element. Is described in Patent Documents 1 and 2 described above.

As means for forming the magnetic flux concentrating plate on the upper part of the CMOSIC having the Hall element built therein, there is a manufacturing technique suitable for industrial production, as can be understood from the description of Patent Document 3 described above.
In the following, for the purpose of explaining the embodiment of the present invention, from the three-dimensional magnetic field vector (Hx, Hy, Hz), the output (electric) signal (Vsig, x, Vsig, y, Vsig, z) corresponding thereto is used. A signal processing method for generating the signal will be described.

In the following description, regarding the structure of the magnetic field measuring apparatus as a premise of the present invention, the output corresponding to the three-dimensional magnetic field vector (Hx, Hy, Hz) input to the three-dimensional magnetic field measuring apparatus ( In the magnetoelectric conversion for generating the (electrical) signal (Vsig, x, Vsig, y, Vsig, z), the problem that the other-axis sensitivity occurs is shown.
The three-dimensional magnetic field measuring apparatus of the present invention cancels the other-axis sensitivity component generated in the output (electrical) signal (Vsig, x, Vsig, y, Vsig, z) and cancels the three-dimensional magnetic field vector (Hx, Hy). , Hz) with high accuracy.

In addition, here, regarding the structure of the magnetic field measuring apparatus as a premise of the present invention, an output (electrical) signal corresponding to the three-dimensional magnetic field vector (Hx, Hy, Hz) input to the three-dimensional magnetic field measuring apparatus. The magnetoelectric conversion for generating (Vsig, x, Vsig, y, Vsig, z) will be described.
When the X-axis component Hx of the input magnetic field is converted into a Z-component magnetic flux by the magnetic focusing plate at the position of the Hall element HallX1, a positive magnetic flux Mzx (HallX1) × Hx is generated. Here, at the position of the Hall element HallX1, the component of the magnetic permeability tensor when the Z-axis component Bz (HallX1) of the magnetic flux is generated from the X-axis component Hx of the magnetic field is Mzx (HallX1).

  At the position of the Hall element HallX1, the Z component Hz of the input magnetic field strength also has a finite value that is not zero. Therefore, the magnetic flux generated by the Z component of the input magnetic field strength is Mzz (HallX1) × Hz. Here, at the position of the Hall element HallX1, the component of the magnetic permeability tensor when the Z-axis component Bz (HallX1) of the magnetic flux density is generated from the Z-axis component Hz of the magnetic field strength is Mzz (HallX1).

  As described above, the Z component of the magnetic flux density penetrating the magnetic sensing surface of the Hall element at the position of the Hall element HallX1 is Mzz (HallX1) × Hx + Mzz (HallX1) × Hz. Here, if the magnetic sensitivity of the Hall element HallX1 is S (HallX1), the Hall electromotive force signal generated in the Hall element HallX1 is Mzz (HallX1) × Hx × S (HallX1) + Mzz (HallX1) × Hz × S ( HallX1).

  The Hall electromotive force signal generated in the Hall element HallX2 is also considered in the same manner as the Hall electromotive force signal generated in the Hall element HallX1, and Mzx (HallX2) × Hx × S (HallX2) + Mzz (HallX2) × Hz × S (HallX2). ) Here, S (HallX2) is the magnetic sensitivity of the Hall element HallX2. Here, the component of the magnetic permeability tensor when the Z-axis component Bz (HallX2) of the magnetic flux density is generated from the X-axis component Hx of the magnetic field at the position of the Hall element HallX2 is Mzx (HallX2). Here, at the position of the Hall element HallX2, the component of the magnetic permeability tensor when the Z-axis component Bz (HallX2) of the magnetic flux density is generated from the Z-axis component Hz of the magnetic field is Mzz (HallX2).

  Based on the above description, when the calculation defined by the calculation formula (5) is performed between the two Hall electromotive force signals generated in the two Hall elements HallX1 and HallX2 arranged on the X axis, a signal is obtained. Vsig, x is obtained. This signal Vsig, x is essentially an electrical signal corresponding to the X-axis component Hx of the magnetic field.

  Similarly, when the calculation defined by the equation (6) is performed between two Hall electromotive force signals generated in the two Hall elements HallY1 and HallY2 arranged on the Y axis, the signal Vsig, y becomes can get. This signal Vsig, y is essentially an electrical signal corresponding to the Y-axis component Hy of the magnetic field.

  Further, as a calculation method for obtaining the electric signal Vsig, z corresponding to the Z-axis component Hz of the magnetic field, here, one specific calculation using two Hall electromotive force signals generated in the two Hall elements HallX1 and HallX2. Use the method. The specific calculation formula is given by Formula (7).

  Here, as a specific calculation method of the electric signal Vsig, z corresponding to the Z-axis component Hz of the magnetic field, a mathematical expression (7) that calculates between the Hall electromotive force signals generated in the Hall elements HallX1 and HallX2. However, unlike this calculation method, it is also possible to use a calculation method for calculating between Hall electromotive force signals generated in the Hall elements HallY1 and HallY2 (a calculation method different from Equation (7)). It is.

Regarding the structure of the magnetic field measuring apparatus which is the premise of the present invention, when the Hall element and the magnetic focusing plate are ideally formed, the other-axis sensitivity that is a problem to be solved by the present invention becomes zero. explain.
Regarding the structure of the magnetic field measuring apparatus which is the premise of the present invention, regarding a phenomenon in which a magnetic flux component Bz perpendicular to the magnetic convergence plate is generated when a three-dimensional magnetic field vector (Hx, Hy, Hz) is input. In the positions of the Hall elements HX1 and HX2, the relationships represented by the formulas (1) and (2) are established, respectively.

  Here, with respect to the structure of the magnetic field measuring apparatus as a premise of the present invention, the magnetic field component Hx in the horizontal direction with respect to the magnetic converging plate is magnetic under the assumption that the Hall element and the magnetic converging plate are ideally formed. As a relational expression regarding a phenomenon in which a magnetic flux component Bz perpendicular to the magnetic converging plate is generated when being input to the converging plate, Equation (8) is established. Under this assumption, it can be easily understood that the same relational expression as the mathematical formula (8) regarding the X axis holds true for the Y axis.

  Similarly, under the assumption that the Hall element and the magnetic converging plate are ideally formed, when the magnetic field component Hz perpendicular to the magnetic converging plate is input to the magnetic converging plate, it is perpendicular to the magnetic converging plate. Equation (9) is established as a relational expression regarding a phenomenon in which a large magnetic flux component Bz is generated.

  In an ideal situation as assumed here, that is, in a situation where the Hall element and the magnetic converging plate are ideally formed, and as a result, the expressions (8) and (9) are satisfied, Vsig, x, Vsig, y , Vsig, z does not generate other-axis sensitivity, as can be seen from equations (5), (6), and (7) as follows.

Actually, looking at the equation (5), under the above assumption, the coefficient of Hz surrounded by [] is zero in the expression of Vsig, x, so in Xsig, z There is no other axis sensitivity that the component of Hz mixes.
Similarly, looking at Equation (6), under the above assumption, the coefficient of Hz surrounded by [] is zero in the expression of Vsig, y, and therefore, in Xsig, y, There is no other axis sensitivity that the component of Hz mixes.

Similarly, looking at Equation (7), under the above assumption, the coefficient of Hx surrounded by [] is zero in the expression of Vsig, z. There is no other axis sensitivity that Hx component is mixed.
As long as the ideal situation where the Hall element and the magnetic converging plate are ideally formed is assumed as described above, the three-dimensional magnetic signal is converted from the three-dimensional magnetic field as understood from the above formula. In the three-dimensional magnetic field measurement for generating a vector, the problem of other axis sensitivity does not occur.

In the following, for the purpose of more easily explaining the problem of other-axis sensitivity, the above formulas (5), (6), and (7) are expressed in a form using a matrix, and the non-diagonal of the matrix there It will be explained that the component is a component corresponding to the other axis sensitivity.
Looking at the equations (5), (6), and (7), the electrical signals Vsig, x, Vsig, corresponding to the spatial components Hx, Hy, Hz of the three-dimensional magnetic field vector (Hx, Hy, Hz). It can be seen that y, Vsig, z are linear combinations of the spatial components Hx, Hy, Hz. Therefore, when the first order coefficients in the relational expression of the linear combination are extracted for each of the electric signals Vsig, x, Vsig, y, Vsig, z, equations (10), (11), and (12) are obtained, respectively.

  The relational expression of the three linear combinations expressed by the above-described mathematical formulas (5), (6), and (7) is a three-dimensional electric signal corresponding to the three-dimensional magnetic field vector (Hx, Hy, Hz). Is written using a matrix M_HtoV of 3 rows and 3 columns, Equation (13) is obtained.

In Equations (10), (11), and (12), symbol D represents a diagonal component (Diagonal component) of matrix M_HtoV, and symbol ND represents a non-diagonal component (Non-diagonal component) of matrix M_HtoV. It is a symbol showing.
In the equations (10) and (11), the non-diagonal components NDxy and NDyx are regarded as zero. Hereinafter, the reason why the non-diagonal components NDxy and NDyx may be regarded as zero will be described with reference to FIG.

  In FIG. 2, the Hall elements HallX1 and HallX2 formed on the X axis and the Hall elements HallY1 and HallY2 formed on the Y axis are manufactured in a CMOS semiconductor manufacturing process. It is manufactured with. Therefore, the angle between the straight line connecting Hall elements HallX1 and HallX2 and the straight line connecting Hall elements HallY1 and HallY2 is 90 ° with very high accuracy. Thus, the non-orthogonality in the XY plane becomes extremely small due to the accuracy of the CMOS semiconductor manufacturing process. This is the reason why these values may be regarded as zero for the off-diagonal components NDxy and NDyx.

Regarding the structure of the magnetic field measuring apparatus which is the premise of the present invention, the mathematical expression (13) is a relational expression (magnetoelectric conversion) for generating a three-dimensional electric signal corresponding to a three-dimensional magnetic field vector (Hx, Hy, Hz). However, the non-diagonal component represented by the symbol ND in the equation (13) has been treated as a value that is extremely close to zero.
As long as the structure of the magnetic field measurement apparatus that is the premise of the present invention is manufactured in an ideal form, with respect to the Cartesian coordinate system set in the three-dimensional magnetic field measurement apparatus, the sensitivity of other axes in the magnetoelectric conversion (the X axis and the Z axis) The other axis sensitivity between them and the other axis sensitivity between Y axis and Z axis) do not occur.

  As an ideal situation (unreal situation), in the equations (10), (11), and (12), the transmission of the magnetic focusing plate is performed between the Hall elements HallX1 and HallX2 and between the Hall elements HallY1 and HallY2. If all of the magnetic susceptibility tensor components are equal and, at the same time, the condition that the magnetic sensitivities of the Hall elements are equal between the Hall elements HallX1 and HallX2 and between the Hall elements HallY1 and HallY2, the symbol ND in the matrix M_HtoV is satisfied. Are all zero, and the matrix M_HtoV is a matrix having only diagonal components as shown in Equation (14).

  As described above, only when an ideal situation is assumed in the structure of the magnetic field measurement apparatus that is the premise of the present invention, based on the electric signals (Vsig, x, Vsig, y, Vsig, z), It can be seen that a three-dimensional magnetic field vector (Hx, Hy, Hz) can be measured with high accuracy.

However, in the structure of the magnetic field measuring apparatus which is the premise of the present invention, the generation of the other-axis sensitivity is made zero in the magnetoelectric conversion from the magnetic field input to the three-dimensional magnetic field measuring apparatus to the corresponding electric signal. Is extremely difficult.
In the structure of the magnetic field measuring apparatus which is the premise of the present invention, as long as the generation of this other axis sensitivity is unavoidable, means for correcting this other axis sensitivity is very important in order to realize highly accurate three-dimensional magnetic field measurement. It becomes important.

  In the following, regarding the structure of the magnetic field measuring apparatus as a premise of the present invention, when the orthogonal coordinate system (X axis, Y axis, Z axis) set in the three-dimensional magnetic field measuring apparatus is a spatial coordinate, the three-dimensional magnetic field measuring apparatus Other axis sensitivity that occurs when converting the input magnetic field vector to the corresponding three-dimensional electric signal vector (other axis sensitivity between X axis and Z axis, other axis sensitivity between Y axis and Z axis) The cause of the occurrence will be described with specific numerical examples.

Regarding the generation of this other-axis sensitivity, one of the prominent causes is a misalignment error between the magnetic focusing plate and the Hall elements (a pair of Hall elements arranged on the X and Y axes).
FIG. 4 is a view for explaining a state of magnetic lines of force penetrating the position of the Hall element HallX1 and the magnetic sensitive surface of the Hall element HallX2 when the relative position between the magnetic focusing plate and the Hall element is deviated from the proper relative position. In the figure, since the distribution of the magnetic flux is different between the positions of the two Hall elements, the other axis sensitivity is shown.

In Patent Document 3 described above, mention is made of the taper of the side surface of the disk-shaped magnetic focusing plate. Regarding the taper of the side surface of the magnetic focusing plate, it is easy to generate other-axis sensitivity in such magnetoelectric conversion even when the degree of taper is different between the position near the Hall element HallX1 and the position near the Hall element HallX2. Will understand.
As another cause of the occurrence of other-axis sensitivity in such magnetoelectric conversion, as easily understood from the equations (5), (6), and (7), the magnetic sensitivity S (HallX1) of the Hall element HallX1 and There may be a mismatch between the magnetic sensitivity S (HallX2) of the Hall element HallX2 and S (HallX1) ≠ S (HallX2).

  Actually, when a Hall element is formed in a silicon substrate (P-type substrate) in a CMOS semiconductor manufacturing process, the Hall element is generally formed as an N-well. For this reason, variations in impurity concentration of the N well due to process gradients in the wafer are the main cause of variations in magnetic sensitivity of the Hall elements. Therefore, in practice, a mismatch of several percent occurs with respect to the magnetic sensitivities S (HallX1) and S (HallX2) of the two Hall elements arranged near both ends of the diameter of the disk-type magnetic converging plate.

As described above, the structure of the magnetic field measurement device that is the premise of the present invention, that is, the structure of the magnetic field measurement device in which the Hall element is arranged near the outer periphery of the magnetic flux converging plate (the magnetic field measurement device described in Patent Documents 1 and 2). In the structure), as described above, the other axis sensitivity related to the Z axis (the other axis sensitivity between the X axis and the Z axis, the other axis sensitivity between the Y axis and the Z axis) occurs due to a plurality of causes. To do.
From the above description, it can be understood that, in the structure of the magnetic field measurement apparatus which is the premise of the present invention, this problem of other axis sensitivity becomes a major obstacle to increasing the measurement accuracy of the three-dimensional magnetic field. I will.

In the following, by examining an example using a specific numerical example for the generation of this other-axis sensitivity, this other-axis sensitivity is a three-dimensional structure using the structure of the magnetic field measurement device which is the premise of the present invention. In the magnetic field measurement, the fact that the magnetic field measurement accuracy is greatly deteriorated will be described.
In order to simplify the exemplary description below, in equations (5), (6), and (7), the tensor components relating to the magnetic permeability of the magnetic focusing plate such as Mzz, Mzy, and Mzz are ideally complete. And the absolute values of the respective tensor components are all 1.0.

Here, regarding the Hall elements HallX1 and HallX2, there is no magnetic sensitivity mismatch between them, and assuming that S (HallX1) = S (HallX1) = 0.5 (ideal matching), Equation (5) , (7) is summarized as (15), and it can be seen that the problem of other-axis sensitivity does not occur.
FIG. 5 illustrates the coordinate axes of the electrical signals Vsig, x, Vsig, z in an ideal case where no other-axis sensitivity is generated for the electrical signals Vsig, x, Vsig, z corresponding to the magnetic components Hx, Hz. The figure shows the relationship between the coordinate axis of the magnetic field vector (Hx, Hz) that is the measurement target of the three-dimensional magnetic field measurement device and the electric signal (Vsig, x, Vsig, z) coordinate axis output by the three-dimensional magnetic field measurement device. ing.

  As can be understood from FIG. 5, as an ideal situation, assuming that no other-axis sensitivity occurs, the orthogonal coordinate axes (X axis, Y axis, Z axis) set in the three-dimensional magnetic field measuring apparatus and Since the coordinate axes of the electrical signals (Vsig, x, Vsig, y, Vsig, z) overlap and coincide completely, the three-dimensional magnetic field measuring device measures the electrical signals (Vsig, x, Vsig, y, Vsig, z) By doing so, it becomes possible to accurately measure the three-dimensional magnetic field vector (Hx, Hy, Hz), which is the measurement target of the three-dimensional magnetic field measuring apparatus.

  Next, in the actual CMOS semiconductor manufacturing process, as a situation that can actually occur, there is a magnetic sensitivity mismatch between Hall elements HallX1 and HallX2, and S (HallX1) = 0.55, S (HallX1) = A situation where 0.45 (magnetic sensitivity mismatch between two Hall elements = ± 10%) will be examined. In this situation, the mathematical formula obtained by combining the mathematical formulas (5) and (7) is (16).

  FIG. 6 is a diagram for explaining the coordinate axes of the electric signals Vsig, x, Vsig, z when the other-axis sensitivity is generated for the electric signals Vsig, x, Vsig, z corresponding to the magnetic components Hx, Hz. The relationship between the coordinate axis of the magnetic field vector (Hx, Hz) that is the measurement target of the three-dimensional magnetic field measurement device and the coordinate axis of the electrical signal (Vsig, x, Vsig, z) output from the three-dimensional magnetic field measurement device is shown.

In FIG. 6, it can be seen that the coordinate axis of (Vsig, x, Vsig, z) is inclined with respect to the coordinate axis of (Hx, Hz). In this way, it can be understood from FIG. 6 that a large error occurs in the three-dimensional magnetic field measurement when the other-axis sensitivity exists.
In the situation shown in FIG. 6, a calculation of θzx = atan (Vsig, z / Vsig, x) is performed based on the electric signal (Vsig, x, Vsig, z) generated by the three-dimensional magnetic field measuring apparatus. When the angle of the electric signal (Vsig, x, Vsig, z) in the ZX plane of the orthogonal coordinate axis set in the three-dimensional magnetic field measuring apparatus is calculated, the result of this angle calculation is as shown in FIG. A large angle error (non-linearity error in angle measurement) of about 6 degrees occurs.

FIG. 7 is a diagram showing an angle measurement error when the angle of the input magnetic field is measured in the ZX plane when the other-axis sensitivity shown in FIG. 6 is present.
As described above, in the structure of the magnetic field measurement apparatus that is the premise of the present invention, the magnetic sensitivity mismatch of + 10% and −10% occurs between the Hall elements HallX1 and HallX2, and the accuracy of the three-dimensional magnetic field measurement is It was shown to deteriorate greatly.

The present invention relates to a structure of a magnetic field measuring apparatus that is a premise of the present invention, that is, a three-dimensional magnetic field measuring apparatus using a structure of a magnetic field measuring apparatus in which a pair of Hall elements are arranged near the outer periphery of a magnetic focusing plate. The means for eliminating the three-dimensional magnetic field measurement error caused by the sensitivity of other axes including the Z axis is shown.
Here, regarding the three-dimensional magnetic field measuring apparatus of the present invention, the three-dimensional magnetic field vector (Hx, Hy, Hz) input to this and the electric signal (Hx, Hy, Hz) corresponding to this three-dimensional magnetic field vector (Hx, Hy, Hz). A correction operation is required to determine the matrix M_HtoV for representing the relationship between Vsig, x, Vsig, y, and Vsig, z) by actual measurement.

As the most easily understood method for this correction operation, (1, 0, 0), (0, 1, 0), (0, 0, 1) are used as the three-dimensional magnetic field vector (Hx, Hy, Hz). It is obvious that the components of the matrix M_HtoV can be obtained by inputting.
From the electric signal (Vsig, x, Vsig, y, Vsig, z) generated by the three-dimensional magnetic field measurement device when the magnetic field vector input to the three-dimensional magnetic field measurement device is (1, 0, 0), the matrix M_HtoV Two components Dxx and NDzx are obtained.

  From the electric signal (Vsig, x, Vsig, y, Vsig, z) generated by the three-dimensional magnetic field measurement device when the magnetic field vector input to the three-dimensional magnetic field measurement device is (0, 1, 0), the matrix M_HtoV Two components Dyy and NDzy are obtained.

  From the electric signal (Vsig, x, Vsig, y, Vsig, z) generated by the three-dimensional magnetic field measurement device when the magnetic field vector input to the three-dimensional magnetic field measurement device is (0, 0, 1), the matrix M_HtoV The three components NDxz, NDyz, and Dzz are obtained.

  Thus, if each component of the matrix M_HtoV can be actually measured as a result of performing the correction operation shown as an example of the simplest correction means, the off-diagonal component of the matrix M_HtoV is a finite value that is not zero. It is possible to correct an error in the generated three-dimensional magnetic field vector measurement.

  As this method, the inverse matrix M_VtoH may be calculated for the matrix M_HtoV obtained by the correcting means.

  For example, with respect to a specific example of the occurrence of the other-axis sensitivity shown in Expression (16), between the electric signals (Vsig, x, Vsig, y, Vsig, z) corresponding to the three-dimensional magnetic field vector (Hx, Hy, Hz). When the matrix M_HtoV for expressing the relationship becomes Equation (22), the matrix M_VtoH that is an inverse matrix of the matrix M_HtoV can be calculated as Equation (20).

  When the signal (Sx, Sy, Sz) is calculated from the electric signal (Vsig, x, Vsig, y, Vsig, z) according to the equation (23) using this matrix M_VtoH, the signals Sx, Sy, Sz are The effect of other axis sensitivity is corrected.

Therefore, in the three-dimensional magnetic field measuring apparatus of the present invention, the three-dimensional magnetic field vector (Hx, Hy, Hz) is measured with high accuracy by calculating the signal (Sx, Sy, Sz) in this way. It becomes possible.
In the above, in the magnetoelectric conversion from the magnetic field vector (Hx, Hy, Hz) input to the three-dimensional magnetic field measuring device to the electric signal (Vsig, x, Vsig, y, Vsig, z) output from the three-dimensional magnetic field measuring device. As a means for realizing a highly accurate three-dimensional magnetic field measurement by correcting (correcting) the problem of other-axis sensitivity, a three-dimensional magnetic field vector (1, 0, 0) input to the three-dimensional magnetic field measuring device, The means for inputting (0, 1, 0), (0, 0, 1) to the three-dimensional magnetic field measuring apparatus has been described from the viewpoint of ease of understanding.

However, as can be easily understood from the above description, the three-dimensional magnetic field vector input to the three-dimensional magnetic field measuring device is not necessarily (1,0,0), (0,1,0), (0, 0, 1) need not be used, and may be three linearly independent vectors.
The three-dimensional magnetic field measurement apparatus according to the present invention is serious in performing high-precision three-dimensional magnetic field measurement in the structure of the magnetic field measurement apparatus as a premise of the present invention by performing the correction operation described so far. It becomes possible to solve the problem of other-axis sensitivity, which is a serious technical problem.

  FIG. 8 is a configuration diagram for explaining an embodiment of the tertiary magnetic field measuring apparatus according to the present invention. In the figure, reference numeral 11 denotes a correction coefficient generation device, 12 (12x, 12y, 12z) denotes a signal processing unit (addition / subtraction circuit / calculation means), 13 denotes an interface circuit, and 14 denotes a correction coefficient storage unit (nonvolatile memory / correction coefficient storage means). ), 15 (15x, 15y, 15z) indicate magnetic field component calculation units (matrix operation circuit / calculation means). In addition, the same code | symbol is attached | subjected to the component which has the same function as FIG.1 and FIG.2.

A three-dimensional magnetic field measurement apparatus 10 according to the present invention is a three-dimensional magnetic field measurement apparatus in which a plurality of magnetic detection elements 3 are arranged around a magnetic body 2 having a magnetic amplification function provided on a semiconductor IC substrate 1. A third signal processing unit 12x, 12y, 12z, a correction coefficient storage unit 14, and a magnetic field component calculation unit 15 are provided.
The first to third signal processing units 12x, 12y, 12z are output signals Vsig, x, which are three-dimensional vector signals corresponding to the three-dimensional magnetic field vectors (Hx, Hy, Hz) input to the magnetic body 2. Vsig, y and Vsig, z are generated.

In addition, the interface circuit 13 performs an operation of reading the electrical signals Vsig, x, Vsig, y, Vsig, z including other-axis sensitivity from the three-dimensional magnetic field measuring apparatus 10 to the outside, and a component of an inverse matrix (M_VtoH) Is written in the nonvolatile memory 14 built in the three-dimensional magnetic field measurement apparatus 10.
The correction coefficient generation device 11 is provided outside the three-dimensional magnetic field measurement device 10 for the purpose of generating correction coefficients. The procedure from generating the correction coefficient to writing the correction coefficient in the correction coefficient storage unit 14 is as follows.

First, as described above, three linearly independent magnetic field vectors are input to the three-dimensional magnetic field measuring apparatus 10, and at that time, the electric signal vector (Vsig, x including the other-axis sensitivity generated by the three-dimensional magnetic field measuring apparatus 10 is generated. , Vsig, y, Vsig, z) are read out to the correction coefficient generation device 11 through the interface circuit 13.
In the correction coefficient generation device 11, the three electric signal vectors (Vsig, x, Vsig, y, Vsig, z) read out in this way are expressed by equations (17), (18), (19). The matrix (M_HtoV) is calculated according to the above formula, and the inverse matrix (M_VtoH) of the matrix (M_HtoV) is further calculated. The inverse matrix (M_VtoH) component is a correction coefficient for correcting the other-axis sensitivity.

Thus, the correction coefficient calculated in the three-dimensional magnetic field measuring apparatus 10 is written to the correction coefficient storage unit 14 through the interface circuit 13.
Therefore, the correction coefficient storage unit 14 stores a correction coefficient for correcting the other-axis sensitivity generated in the magnetoelectric conversion that generates the three-dimensional output signals by the first to third signal processing units 12x, 12y, and 12z. is there.

The magnetic field component calculation unit 15 includes an X-axis direction magnetic field component calculation unit 15x, a Y-axis direction magnetic field component calculation unit 15y, and a Z-axis direction magnetic field component calculation unit 15z, and is stored in the correction coefficient storage unit 14. A three-dimensional output signal is calculated based on the coefficient.
The other-axis sensitivity is generated due to a relative positional shift between the magnetic body 2 and the magnetic detection elements 3X1, 3X2, 3Y1, 3Y2. The other-axis sensitivity is generated by an error in the magnetic sensitivity of the magnetic detection elements 3X1 and 3X2 or 3Y1 and 3Y2 of the magnetic detection element pairs 3X1 / 3X2 and 3Y1 / 3Y2 arranged on the X axis and the Y axis. is there.

A relational expression of magnetoelectric conversion for generating the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z is represented by a matrix (M_HtoV).
The first to third signal processing units 12x, 12y, and 12z are preferably addition / subtraction circuits. The magnetic field component calculation unit 15 is preferably composed of a matrix operation circuit. The matrix operation circuit performs an operation of multiplying a three-dimensional output signal vector (Vsig, x, Vsig, y, Vsig, z) by an inverse matrix (M_VtoH) to obtain another three-dimensional vector signal (Sx, Sy, Sz).

The magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 are preferably Hall elements.
The three-dimensional magnetic field measurement apparatus 10 of the present invention includes first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 disposed in the vicinity of the magnetic body 2, a first signal processing unit 12x, 2 signal processing units 12y, a third signal processing unit 12z, a correction coefficient storage unit 14, and a magnetic field component calculation unit 15.

  The first signal processing unit 12x receives the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2, and receives the output of the first magnetic detection element 3X1. A signal Vsig, x based on the difference or sum of the output signal Vsig (HallX1) and the output signal Vsig (HallX2) of the second magnetic detection element 3X2 is output.

  The second signal processing unit 12y receives the output signal Vsig (HallY1) of the third magnetic detection element 3Y1 and the output signal Vsig (HallY2) of the fourth magnetic detection element 3Y2, and receives the third magnetic detection element. A signal Vsig, y based on the difference or sum of the output signal Vsig (HallY1) of 3Y1 and the output signal Vsig (HallY2) of the fourth magnetic detection element 3Y2 is output.

  The third signal processing unit 12z receives the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2, and receives the first magnetic detection element. A signal based on the sum or difference of the output signal Vsig (HallX1) of 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2, and outputs a signal Vsig, z different from that of the first signal processing unit 12x It is.

Further, the correction coefficient storage unit 14 has other axis sensitivity generated in the magnetoelectric conversion for generating the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z by the first to third signal processing units 12x to 12z. This is for storing a correction coefficient to be corrected.
In addition, the magnetic field component calculation unit 15 generates the magnetic field component in the X-axis direction based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficients of the first to third signal processing units 12x to 12z, and X A magnetic field component in the Y-axis direction orthogonal to the axial direction and a magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction are calculated.

  Further, the value indicated by the signal output from the first signal processing unit 12x is Vsig, x, the value indicated by the signal output from the second signal processing unit 12y is Vsig, y, and the third signal processing unit 12z outputs the value. When the value indicated by the signal is Vsig, z, the correction coefficient is a three-dimensional vector signal Vsig, x, Vsig, y, Vsig, z, which is a three-dimensional output signal, and other three-dimensional vector signals Sx, Sy, This is a coefficient for conversion to Sz.

  Further, the correction coefficients are the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, 3Y2 when the first magnetic field, the second magnetic field, and the third magnetic field are applied to the three-dimensional magnetic field measuring apparatus 10. Is a coefficient calculated based on the output signals Vsig (HallX1) to Vsig (HallY2) output from. In addition, the first magnetic field, the second magnetic field, and the third magnetic field are magnetic fields that are linearly independent from each other.

  Further, when the two orthogonal directions are defined as the X′-axis direction, the Y′-axis direction, and the Z′-axis direction, the first magnetic field has a magnetic field component in the X′-axis direction, and the Y′-axis direction. And the second magnetic field has a magnetic field component in the Y′-axis direction, a magnetic field component in the X′-axis direction, and a magnetic field component Z in the Z′-axis direction. 'A magnetic field component having a very small amount of magnetic field component in the axial direction and having substantially no magnetic field component. The third magnetic field has a magnetic field component in the Z' axis direction, and a magnetic field component in the X 'axis direction and a magnetic field in the Y' axis direction. It is a magnetic field that has very few components and substantially no magnetic field.

The X-axis direction and the X′-axis direction are the same direction, the Y-axis direction and the Y′-axis direction are the same direction, and the Z-axis direction and the Z′-axis direction are the same direction.
The correction coefficient is α1 (Dxx in Equation 17), a value based on the signal Vsig, x output from the first signal processing unit 12x when the first magnetic field is applied to the three-dimensional magnetic field measurement apparatus 10. The value based on the signal Vsig, z output from the third signal processing unit 12z when the first magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10 is α2 (NDzx in Expression 17), and the second magnetic field is the three-dimensional magnetic field. When a value based on the signal Vsig, y output from the second signal processing unit 12y when applied to the measuring device 10 is β1 (Dyy in Equation 17) and a second magnetic field is applied to the three-dimensional magnetic field measuring device 10 The first signal processing unit when a value based on the signal Vsig, z output from the third signal processing unit 12z is β2 (NDzy in Expression 17) and a third magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10. Signal V output from 12x The value based on the signal Vsig, y output from the second signal processing unit 12y when the value based on ig, x is γ1 (NDxz in Equation 17) and the third magnetic field is applied to the three-dimensional magnetic field measurement apparatus 10. γ2 (NDyz in Expression 17), and a value based on the signal Vsig, z output from the third signal processing unit 12z when a third magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10 is expressed as γ3 (Dzz in Expression 17). Is a value based on α1, α2, β1, β2, γ1, γ2, and γ3.

Further, in the third signal processing unit 12z, the output signals of the first to fourth magnetic detection elements 3X1 and 3X2 are input, and the sum or difference of the output signals of the first to fourth magnetic detection elements 3X1 and 3X2 is calculated. Based signal is output.
The magnetic field component calculation unit 15 calculates the magnetic field component in the X-axis direction based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficients of the first to third signal processing units 12x to 12z. Based on the output signals Vsig, x, Vsig, y, Vsig, z and correction coefficients of the X-axis direction magnetic field component calculation unit 15x and the first to third signal processing units 12x to 12z, the magnetic field component in the Y-axis direction is calculated. Based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficient of the Y-axis direction magnetic field component calculation unit 15y and the first to third signal processing units 12x to 12z, the magnetic field component in the Z-axis direction is calculated. And a Z-axis direction magnetic field component calculation unit 15z for calculation.

  Further, the semiconductor IC substrate 1 on which the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 are arranged is provided, and the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 are the first A straight line connecting the magnetic detection element 3X1 and the second magnetic detection element 3X2 and a straight line connecting the third magnetic detection element 3Y1 and the fourth magnetic detection element 3Y2 are arranged to be orthogonal to each other.

Further, the direction of the straight line from the first magnetic detection element 3X1 to the second magnetic detection element 3X2 is the same as the X-axis direction, and the third magnetic detection element 3Y1 is directed to the fourth magnetic detection element 3Y2. The direction of the straight line and the Y-axis direction are the same direction.
The shape of the magnetic body 2 is circular, the center of the magnetic body 2, the straight line connecting the first magnetic detection element 3X1 and the second magnetic detection element 3X2, and the third magnetic detection element 3Y1. And a line connecting the fourth magnetic detection element 3Y2 are arranged at positions that coincide with each other when the semiconductor IC substrate 1 is viewed in plan view.

  The three-dimensional magnetic field measuring apparatus of the present invention shown in FIG. 8 has the structure of a magnetic field measuring apparatus in which a pair of Hall elements is arranged near the outer periphery of the magnetic focusing plate. In this three-dimensional magnetic field measuring apparatus, With respect to the set orthogonal coordinate system (X axis, Y axis, Z axis), Hall elements HallX1 and HallX2 that are paired on the X axis are arranged, and Hall elements HallY1 and HallY2 that are paired on the Y axis are arranged. Is arranged.

After the Hall electromotive force signals generated in the Hall elements HallX1 and HallX2 and HallY1 and HallY2 that are paired with each other are amplified, the adder / subtracter circuit 12 defines the following equations (5), (6), and (7). By executing the signal processing, a three-dimensional electrical signal (Vsig, x, Vsig, y, Vsig, z) is generated.
Further, the matrix calculation circuit 14 performs a calculation (signal processing defined by Expression 23) by multiplying the three-dimensional electrical signal (Vsig, x, Vsig, y, Vsig, z) by the matrix M_VtoH, thereby performing a three-dimensional operation. A vector (Sx, Sy, Sz) is obtained. Here, the values of the components of the matrix M_VtoH are stored in the nonvolatile memory.

  Here, the output signal of the three-dimensional magnetic field measuring apparatus of the present invention is a signal derived from the above-described three-dimensional vector signal (Sx, Sy, Sz) or the above-described three-dimensional vector signal (Sx, Sy, Sz). Become. As an example of a signal derived from the above-described three-dimensional vector signal (Sx, Sy, Sz), an orthogonal coordinate system (X-axis, Y-axis, Z-axis) set in the three-dimensional magnetic field measuring apparatus is in the XY plane. There are an angle θxy of the vector (Hx, Hy) at, an angle θyz of the vector (Hy, Hz) in the YZ plane, and an angle θzx of the vector (Hz, Hx) in the ZX plane.

  The three-dimensional magnetic field measuring device that outputs these angle θxy, angle θyz, and angle θzx should be used as a three-dimensional rotational angle sensor that measures the three-dimensional rotational position of a magnetic material placed in the vicinity of the three-dimensional magnetic field measuring device. Can do. As for the calculation method of θxy, θyz, and θzx, an arctangent calculation such as θxy = atan (Sy / Sx), θyz = atan (Sz / Sy), and θzx = atan (Sx / Sz) may be performed. Actually, when performing these arc tangent operations, an AD converter is used to measure a three-dimensional vector signal (Sx, Sy, Sz) as a digitized signal, and a CORDIC (Cordate Rotation Digital Computing) algorithm. As generally known algorithms can be used.

The three-dimensional magnetic field measuring apparatus shown in FIG. 8 is very suitable for realization in the form of a silicon monolithic magnetic field measuring apparatus in which a magnetic focusing plate is arranged on top of a CMOSIC in which a Hall element is formed inside a semiconductor IC substrate. It is a thing.
As described above, according to the three-dimensional magnetic field measuring apparatus of the present invention, it is possible to correct the other-axis sensitivity when measuring by converting the magnetic field of each component of the X axis, the Y axis, and the Z axis into an electric signal. . In particular, it can be applied to an electronic compass, a three-dimensional rotation angle sensor, and the like.

The three-dimensional magnetic field measurement apparatus of the present invention can be used particularly suitably for a three-dimensional magnetic field measurement apparatus having a configuration in which other-axis sensitivity is generated. The other-axis sensitivity is, for example, in the three-dimensional magnetic field measuring apparatus including the magnetic body 2 and the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 disposed in the vicinity of the magnetic body 2. Is a point-symmetric shape, and when the magnetic body 2 is viewed in plan, the position of the midpoint of the line segment connecting the magnetic detection element 3X1 and the magnetic detection element 3X2 is different from the position of the symmetry point of the magnetic body This occurs when the position of the midpoint of the line segment connecting the magnetic detection element 3Y1 and the magnetic detection element 3Y2 is different from the position of the symmetry point of the magnetic body. In addition, when the magnetic sensitivities of the magnetic detection element 3X1 and the magnetic detection element 3X2 are different, or when the magnetic sensitivities of the magnetic detection element 3Y1 and the magnetic detection element 3Y2 are different, they are covered with the magnetic material of the magnetic sensing part of the magnetic detection element 3X1. The area of the magnetic sensing element 3X2 is different from the area covered by the magnetic body of the magnetic sensing element 3X2, or the area of the magnetic sensing element 3Y1 covered by the magnetic body of the magnetic sensing element This occurs when the areas of the portions of the magnetic sensing element 3Y2 covered by the magnetic material of the magnetic sensing part are different.
FIG. 9 is a flowchart of a correction procedure in the magnetic field measurement method of the three-dimensional magnetic field measurement apparatus according to the present invention.

The three-dimensional magnetic field measurement method of the present invention is a three-dimensional magnetic field measurement method in a three-dimensional magnetic field measurement apparatus in which a plurality of magnetic detection elements 3 are arranged around a magnetic convergence plate 2 provided on a semiconductor IC substrate 1.
First, when a correction operation is started, a correction magnetic field having a constant magnetic field component only in the X-axis direction is input, and output (electric) signals (Vsig, x, Vsig, y, Vsig, z) are measured (step) S1).

Next, a correction magnetic field having a constant magnetic field component only in the Y-axis direction is input, and output (electric) signals (Vsig, x, Vsig, y, Vsig, z) are measured (step S2).
Next, a correction magnetic field having a constant magnetic field component only in the Z-axis direction is input, and output (electric) signals (Vsig, x, Vsig, y, Vsig, z) are measured (step S3).
Next, a matrix (M_HtoV) is calculated based on the signal measured in the correction. Also, an inverse matrix (M_VtoH) is calculated (step S4). Next, a component of an inverse determinant (M_VtoH) serving as a correction coefficient for correcting other-axis sensitivity generated in magnetoelectric conversion for generating a three-dimensional output (electric) signal (Vsig, x, Vsig, y, Vsig, z) Is stored in a non-volatile memory in a CMOSIC which is a three-dimensional magnetic field measuring device (step S5).

In the correction procedure shown in FIG. 9, three three-dimensional magnetic field vectors that are linearly independent from each other are input to a three-dimensional magnetic field measuring apparatus, and electrical signals (Vsig, x, Vsig, By measuring y, Vsig, z), the components of the matrix M_HtoV are measured.
When the three-dimensional magnetic field measurement apparatus of the present invention is realized in the form of silicon monolithic, the operation of the process of calculating the matrix M_VtoH that is the inverse matrix from the measured matrix M_HtoV corrects the silicon monolithic magnetic field measurement apparatus. And correcting the silicon monolithic three-dimensional magnetic field measuring device by writing the calculated matrix M_VtoH component into a non-volatile memory prepared in the silicon monolithic magnetic field measuring device. It can be carried out.

Hereinafter, the three-dimensional magnetic field measuring method of the present invention will be described in more detail. The three-dimensional magnetic field measurement method of the present invention has a calculation step, a correction coefficient storage step, and a calculation step.
In the first to third signal processing units 12x, 12y, and 12z, the calculation step includes an output signal Vsig, which is a three-dimensional vector signal corresponding to the three-dimensional magnetic field vector Hx, Hy, Hz input to the magnetic body 2. x, Vsig, y, and Vsig, z are generated.

In the correction coefficient storage step, the correction coefficient storage unit 14 corrects the other-axis sensitivity generated in the magnetoelectric conversion for generating the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z by the calculation step. Is memorized.
In the calculation step, the magnetic field component calculation unit 15 calculates a three-dimensional output signal based on the correction coefficient stored in the correction coefficient storage step.

  The other axis sensitivity means the other axis sensitivity between the X axis and the Z axis and the other axis sensitivity between the Y axis and the Z axis. The other-axis sensitivity is generated by a relative positional shift between the magnetic body 2 and the magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2. The other-axis sensitivity is generated by an error in the magnetic sensitivity of the magnetic detection elements 3X1 and 3X2 or 3Y1 and 3Y2 of the magnetic detection element pairs 3X1 / 3X2 and 3Y1 / 3Y2 arranged on the X axis and the Y axis. is there.

A relational expression of magnetoelectric conversion for generating the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z is represented by a matrix (M_HtoV).
Further, the calculation step includes an addition / subtraction step including first to third signal processing units 12x to 12z. Further, the calculation step is processed by the magnetic field component calculation unit 15, and the magnetic field component calculation unit 15 has a matrix calculation step.

In the matrix operation step, another three-dimensional vector signal Sx, Sy, Sz is obtained by performing an operation of multiplying the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z by an inverse matrix (M_VtoH). Is.
The magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 are desirably Hall elements.

The three-dimensional magnetic field measurement method of the present invention includes first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 disposed in the vicinity of the magnetic body 2, and includes a first signal processing step and a second signal processing step. A signal processing step, a third signal processing step, a correction coefficient storage step, and a magnetic field component calculation step.
In the first signal processing step, the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2 are input in the first signal processing unit 12x. A signal Vsig, x based on the difference or sum of the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2 is output.

  In the second signal processing step, the output signal Vsig (HallY1) of the third magnetic detection element 3Y1 and the output signal Vsig (HallY2) of the fourth magnetic detection element 3Y2 are input in the second signal processing unit 12y. The signal Vsig, y based on the difference or sum of the output signal Vsig (HallY1) of the third magnetic detection element 3Y1 and the output signal Vsig (HallY2) of the fourth magnetic detection element 3Y2 is output.

  In the third signal processing step, the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2 are input in the third signal processing unit 12z. The signal is based on the sum or difference of the output signal Vsig (HallX1) of the first magnetic detection element 3X1 and the output signal Vsig (HallX2) of the second magnetic detection element 3X2, and is different from the first signal processing unit 12x. The signal Vsig, z is output.

The correction coefficient storage step is a magnetoelectric conversion in the correction coefficient storage unit 14 that generates the three-dimensional output signals Vsig, x, Vsig, y, Vsig, z by the first to third signal processing units 12x to 12z. A correction coefficient for correcting the generated other-axis sensitivity is stored.
In the magnetic field component calculation step, in the magnetic field component calculation unit 15, the magnetic field component in the X-axis direction is based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficient of the first to third signal processing steps. Then, the magnetic field component in the Y-axis direction orthogonal to the X-axis direction and the magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction are calculated.

  Further, the value indicated by the signal output from the first signal processing step is Vsig, x, the value indicated by the signal output from the second signal processing step is Vsig, y, and the signal output from the third signal processing step is indicated. When the value is Vsig, z, the correction coefficient is converted from the three-dimensional vector signal Vsig, x, Vsig, y, Vsig, z, which is a three-dimensional output signal, to other three-dimensional vector signals Sx, Sy, Sz. It is a coefficient to do.

  Further, the correction coefficients are the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, 3Y2 when the first magnetic field, the second magnetic field, and the third magnetic field are applied to the three-dimensional magnetic field measuring apparatus 10. Is a coefficient calculated based on the output signals Vsig (HallX1) to Vsig (HallY2) output from. Further, the first magnetic field, the second magnetic field, and the third magnetic field are magnetic fields that are linearly independent from each other.

  Further, when the two orthogonal directions are defined as the X′-axis direction, the Y′-axis direction, and the Z′-axis direction, the first magnetic field has a magnetic field component in the X′-axis direction, and the Y′-axis direction. And the second magnetic field has a magnetic field component in the Y′-axis direction, a magnetic field component in the X′-axis direction, and a magnetic field component Z in the Z′-axis direction. 'A magnetic field component having a very small amount of magnetic field component in the axial direction and having substantially no magnetic field component. The third magnetic field has a magnetic field component in the Z' axis direction, and a magnetic field component in the X 'axis direction and a magnetic field in the Y' axis direction. It is a magnetic field that has very few components and substantially no magnetic field.

The X-axis direction and the X′-axis direction are the same direction, the Y-axis direction and the Y′-axis direction are the same direction, and the Z-axis direction and the Z′-axis direction are the same direction.
The correction coefficient is α1 (Dxx in Expression 17), a value based on the signal Vsig, x output from the first signal processing step when the first magnetic field is applied to the three-dimensional magnetic field measurement apparatus 10. The value based on the signal Vsig, z output from the third signal processing step when the magnetic field of 1 is applied to the three-dimensional magnetic field measurement apparatus 10 is α2 (NDzx in Expression 17), and the second magnetic field is measured in three-dimensional magnetic field. A value based on the signal Vsig, y output from the second signal processing step when applied to the apparatus 10 is β1 (Dyy in Expression 17), and the second magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10 when the second magnetic field is applied. 3 is output from the first signal processing step when a value based on the signal Vsig, z output from the signal processing step 3 is β2 (NDzy in Expression 17) and the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10. Belief A value based on Vsig, x is γ1 (NDxz in Expression 17), and a value based on the signal Vsig, y output from the second signal processing step when the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10 is γ2. (NDyz in Equation 17), and a value based on the signal Vsig, z output from the third signal processing step when the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus 10 is γ3 (Dzz in Equation 17). Values based on α1, α2, β1, β2, γ1, γ2, and γ3.

In the third signal processing step, the output signals of the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 are inputted, and the first to fourth magnetic detection elements 3X1, 3X2, 3Y1, and 3Y2 A signal based on the sum or difference of the output signals is output.
The magnetic field component calculating step calculates the magnetic field component in the X-axis direction based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficient in the first to third signal processing steps. Y-axis direction magnetic field component calculation step for calculating the Y-axis direction magnetic field component based on the component calculation step and the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficient of the first to third signal processing steps And a Z-axis direction magnetic field component calculation step for calculating a magnetic field component in the Z-axis direction based on the output signals Vsig, x, Vsig, y, Vsig, z and the correction coefficient of the first to third signal processing steps. doing.

As described above, according to the three-dimensional magnetic field measurement method of the present invention, correction and correction (correction) of other-axis sensitivity when the magnetic field of each component of the X-axis, Y-axis, and Z-axis is converted into an electric signal and measured. Can do. In particular, it can be applied to an electronic compass, a three-dimensional rotation angle sensor, and the like.
The three-dimensional magnetic field measuring method of the present invention can be particularly preferably applied to a three-dimensional magnetic field measuring apparatus configured to generate other-axis sensitivity.

1 Semiconductor IC substrate (CMOSIC)
2 Magnetic material (magnetic convergence plate)
3 (3X1, 3X2, 3Y1, 3Y2) Magnetic detection element (Hall element)
4 outer periphery of magnetic focusing plate 10 three-dimensional magnetic field measuring device 11 correction coefficient generating device 12 (12x to 12z) signal processing unit (addition / subtraction circuit)
13 Interface circuit 14 Correction coefficient storage unit (nonvolatile memory)
15 (15x to 15z) Magnetic field component calculation unit (matrix operation circuit)

Claims (21)

Magnetic material,
First to fourth magnetic sensing elements disposed in the vicinity of the magnetic body;
In a three-dimensional magnetic field measuring apparatus comprising:
A calculation unit that generates an output signal corresponding to a magnetic field applied to the three-dimensional magnetic field measurement device based on output signals of the first to fourth magnetic detection elements;
A correction coefficient storage unit that stores a correction coefficient for correcting the other-axis sensitivity component included in the output signal of the calculation unit;
The magnetic field component in the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measurement device based on the output signal of the arithmetic unit and the correction coefficient; the magnetic field component in the Y-axis direction orthogonal to the X-axis direction; A calculation unit for calculating a magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction;
A three-dimensional magnetic field measuring apparatus. The computing unit is
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the difference or sum of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A first signal processing unit for outputting a signal based on
The output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element are input, and the difference or sum of the output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element A second signal processing unit for outputting a signal based on
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the sum or difference of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A third signal processing unit that outputs a signal different from that of the first signal processing unit,
The three-dimensional magnetic field measuring apparatus according to claim 1, comprising: Magnetic material,
First to fourth magnetic sensing elements disposed in the vicinity of the magnetic body;
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the difference or sum of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A first signal processing unit for outputting a signal based on
The output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element are input, and the difference or sum of the output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element A second signal processing unit for outputting a signal based on
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the sum or difference of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A third signal processing unit that outputs a signal different from that of the first signal processing unit,
A correction coefficient storage unit for storing a correction coefficient for correcting the output signals of the first to third signal processing units;
Based on the output signals of the first to third signal processing units and the correction coefficient, the magnetic field component in the X-axis direction, the magnetic field component in the Y-axis direction orthogonal to the X-axis direction, the X-axis direction, and the Y-axis A magnetic field component calculation unit for calculating a magnetic field component in the Z-axis direction orthogonal to the direction;
A three-dimensional magnetic field measuring apparatus. The value indicated by the signal output from the first signal processing unit is Vsig, x,
The value indicated by the signal output from the second signal processing unit is represented by Vsig, y,
The value indicated by the signal output from the third signal processing unit is expressed as Vsig, z
And when
The correction factor is
The three-dimensional magnetic field measuring apparatus according to claim 2 or 3, wherein the three-dimensional vector signal is a coefficient for converting a three-dimensional vector signal into another three-dimensional vector signal. The correction factor is
A coefficient calculated based on output signals output from the first to fourth magnetic detection elements when the first magnetic field, the second magnetic field, and the third magnetic field are applied to the three-dimensional magnetic field measuring apparatus. The three-dimensional magnetic field measuring apparatus according to claim 1, wherein   The three-dimensional magnetic field measurement apparatus according to claim 5, wherein the first magnetic field, the second magnetic field, and the third magnetic field are linearly independent magnetic fields. When the three orthogonal directions are defined as the X ′ axis direction, the Y ′ axis direction, and the Z ′ axis direction, respectively,
The first magnetic field is a magnetic field having a magnetic field component in the X′-axis direction and having very little magnetic field component in the Y′-axis direction and magnetic field component in the Z′-axis direction,
The second magnetic field is a magnetic field having a magnetic field component in the Y′-axis direction and having very little magnetic field component in the X′-axis direction and magnetic field component in the Z′-axis direction,
The three-dimensional magnetic field according to claim 5 or 6, wherein the third magnetic field is a magnetic field having a magnetic field component in the Z'-axis direction and having a very small magnetic field component in the X'-axis direction and a magnetic field component in the Y'-axis direction. measuring device.   The X-axis direction and the X′-axis direction are the same direction, the Y-axis direction and the Y′-axis direction are the same direction, and the Z-axis direction and the Z′-axis direction are the same direction. The three-dimensional magnetic field measuring apparatus described in 1. The correction factor is
A value based on a signal output from the first signal processing unit when the first magnetic field is applied to the three-dimensional magnetic field measuring apparatus is α1,
A value based on a signal output from the third signal processing unit when the first magnetic field is applied to the three-dimensional magnetic field measuring apparatus is α2,
A value based on a signal output from the second signal processing unit when the second magnetic field is applied to the three-dimensional magnetic field measuring apparatus is β1,
A value based on a signal output from the third signal processing unit when the second magnetic field is applied to the three-dimensional magnetic field measuring apparatus is β2,
A value based on a signal output from the first signal processing unit when the third magnetic field is applied to the three-dimensional magnetic field measurement apparatus is γ1,
A value based on a signal output from the second signal processing unit when the third magnetic field is applied to the three-dimensional magnetic field measuring apparatus is γ2,
When a value based on a signal output from the third signal processing unit when the third magnetic field is applied to the three-dimensional magnetic field measurement device is γ3,
The three-dimensional magnetic field measuring apparatus according to any one of claims 5 to 8, wherein the three-dimensional magnetic field measuring apparatus is a value based on the α1, α2, β1, β2, γ1, γ2, and γ3.   The third signal processing unit receives the output signals of the first to fourth magnetic detection elements, and outputs a signal based on the sum or difference of the output signals of the first to fourth magnetic detection elements. The three-dimensional magnetic field measuring apparatus according to claim 2. The magnetic field component calculation unit
An X-axis direction magnetic field component calculation unit for calculating a magnetic field component in the X-axis direction based on the output signals of the first to third signal processing units and the correction coefficient;
A Y-axis direction magnetic field component calculation unit for calculating a magnetic field component in the Y-axis direction based on the output signals of the first to third signal processing units and the correction coefficient;
A Z-axis direction magnetic field component calculation unit that calculates a magnetic field component in the Z-axis direction based on the output signals of the first to third signal processing units and the correction coefficient;
The three-dimensional magnetic field measuring apparatus according to claim 3, comprising:   The semiconductor IC substrate on which the first to fourth magnetic detection elements are arranged, wherein the first to fourth magnetic detection elements include the first magnetic detection element and the second magnetic detection element. The three-dimensional magnetic field according to any one of claims 1 to 11, wherein a connecting straight line and a straight line connecting the third magnetic detection element and the fourth magnetic detection element are arranged so as to be substantially orthogonal to each other. measuring device.   The straight line direction from the first magnetic detection element to the second magnetic detection element and the X-axis direction are the same direction, and the straight line from the third magnetic detection element to the fourth magnetic detection element The three-dimensional magnetic field measuring apparatus according to claim 12, wherein the direction and the Y-axis direction are the same. The first to fourth magnetic detection elements are:
The three-dimensional magnetic field measurement apparatus according to any one of claims 1 to 13, wherein when the magnetic body is viewed in plan, at least a part of a magnetic sensing portion of each magnetic detection element is disposed at a position covered with the magnetic body. .   The three-dimensional magnetic field measuring apparatus according to claim 1, wherein the magnetic body has a circular shape or a polygonal shape. The shape of the magnetic body is a point-symmetric shape,
When the magnetic body is viewed in plan view,
The three-dimensional according to any one of claims 1 to 15, wherein a position of a midpoint of a line segment connecting the first magnetic detection element and the second magnetic detection element is different from a position of a symmetry point of the magnetic body. Magnetic field measuring device.   The three-dimensional magnetic field measuring apparatus according to any one of claims 1 to 16, wherein a magnetic sensitivity of the first magnetic detection element is different from a magnetic sensitivity of the second magnetic detection element. When the magnetic body is viewed in plan view,
The area of the magnetic sensing part of the first magnetic sensing element covered by the magnetic material is different from the area of the magnetic sensing part of the second magnetic sensing element covered by the magnetic material. The three-dimensional magnetic field measuring apparatus according to any one of claims 1 to 17, which is an area.   The three-dimensional magnetic field measuring apparatus according to claim 1, wherein the magnetic detection element is a Hall element. Magnetic material,
First to fourth magnetic sensing elements disposed in the vicinity of the magnetic body;
A three-dimensional magnetic field measurement method using a three-dimensional magnetic field measurement apparatus comprising:
A calculation step of generating an output signal corresponding to a magnetic field applied to the three-dimensional magnetic field measurement device based on output signals of the first to fourth magnetic detection elements;
A correction coefficient storage step for storing a correction coefficient for correcting the other-axis sensitivity component included in the signal generated in the calculation step;
A magnetic field component in the X-axis direction of the magnetic field applied to the three-dimensional magnetic field measurement device based on the signal generated in the calculation step and the correction coefficient; and a magnetic field component in the Y-axis direction orthogonal to the X-axis direction; Calculating a magnetic field component in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction;
A three-dimensional magnetic field measuring method comprising: A magnetic body, and first to fourth magnetic detection elements disposed in the vicinity of the magnetic body;
A three-dimensional magnetic field measurement method using a three-dimensional magnetic field measurement apparatus comprising:
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the difference or sum of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A first signal processing step for outputting a signal based on:
The output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element are input, and the difference or sum of the output signal of the third magnetic detection element and the output signal of the fourth magnetic detection element A second signal processing step for outputting a signal based on:
The output signal of the first magnetic detection element and the output signal of the second magnetic detection element are input, and the sum or difference of the output signal of the first magnetic detection element and the output signal of the second magnetic detection element A third signal processing step for outputting a signal different from the first signal processing step,
A correction coefficient storage step for storing a correction coefficient for correcting the output signal of the first to third signal processing steps;
Based on the output signals of the first to third signal processing steps and the correction coefficient, the magnetic field component in the X-axis direction, the magnetic field component in the Y-axis direction orthogonal to the X-axis direction, the X-axis direction, and the Y-axis A magnetic field component calculating step for calculating a magnetic field component in the Z-axis direction orthogonal to the direction;
A three-dimensional magnetic field measuring method comprising:

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