JP2022152122A - Measurement device and method for measurement - Google Patents

Abstract

To make it easier to quickly discover people who have fallen under the ground and are waiting for a rescue.SOLUTION: The measurement device according to the present invention includes: a current application unit for applying an AC current to a measurement target in a position away from the measurement target; a magnetic field detection element for detecting an induction magnetic field generated from the measurement target according to the AC current; and an information output unit for outputting information that shows a change with time of the result of detection of the induction magnetic field by the magnetic field detection element, which corresponds to a change with time of the measurement target. The current application unit may apply an AC current in plural parts of the measurement target.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a measuring device and a measuring method.

Due to earthquakes, typhoons, torrential rains, accidents, etc., people may be buried alive for a long time in earth and sand, rubble, houses, etc. In this case, it is necessary to rescue the buried alive as soon as possible, and techniques for finding the rescuer are being proposed (see Patent Document 1, for example).

JP-A-2002-311153

S. Nebuya, A. Fujimaki, B. H. Brown, M. Noshiro "Impedance changes produced by passage of emboli through carotid artery," Electronics Letters, vol. 44, No. 6, pp. 397-398 (2008)

However, for example, a radar device using reflection of radio waves of about 200 MHz to 800 MHz is superior in detecting radio wave reflecting substances such as metals to identifying a human body, and it is difficult to distinguish between a dead body and a living body. In addition, a Doppler radar has been proposed that uses microwaves of about 1 GHz to 2 GHz and measures the periodic shift in phase of waves reflected from the chest surface due to respiration, but microwaves are greatly attenuated by water absorption. Therefore, there is a problem that the effect cannot be exhibited in earth and sand containing water. Therefore, there has been a demand for a sensing technology capable of quickly finding a rescued person buried underground.

Accordingly, the present invention has been made in view of these points, and it is an object of the present invention to quickly find a rescuer buried underground.

In a first aspect of the present invention, a current applying unit that applies an alternating current toward the object to be measured at a position away from the object to be measured, and detects an induced magnetic field generated from the object to be measured according to the alternating current. Provided is a measuring apparatus comprising a magnetic field detection element, and an information output unit for outputting information indicating a temporal change in the detection result of the induced magnetic field by the magnetic field detection element, corresponding to a temporal change in the object to be measured. .

The current applying section applies the alternating current to a plurality of portions of the object to be measured, and the information output section outputs temporal changes in detection results of the induced magnetic field by the magnetic field detecting element for each of the plurality of portions. may

The current applying section may apply the alternating current with a frequency of 10 kHz or higher toward the object to be measured.

The current applying unit has a plurality of electrode pairs, and applies a current from a first electrode pair among the plurality of electrode pairs toward the measurement object, and a second electrode pair different from the first electrode pair. may be used to detect a potential difference corresponding to the applied current, and the information output unit may further output a temporal change in impedance calculated from the potential difference detected by the second electrode pair.

In a second aspect of the present invention, applying an alternating current toward the object to be measured at a position away from the object to be measured; and detecting an induced magnetic field generated from the object to be measured according to the plurality of alternating currents. and outputting information indicating a temporal change in a detection result of an induced magnetic field corresponding to the temporal change in the object to be measured.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in being able to quickly find the rescuer buried underground.

A first configuration example of the measurement apparatus 100 according to the present embodiment is shown together with the measurement target 10 . Examples of conductivity of organs and substances used in this embodiment are shown. FIG. 2 shows a conceptual diagram of a current density distribution calculated in a simulation of the present embodiment; An example of the amount of change in impedance calculated in the simulation of the present embodiment is shown. 4 shows the relationship between the measurement distance and the detection sensitivity in the impedance method and the magnetic field measurement method used in this embodiment. The results of sensitivity comparison between the impedance method and the magnetic field measurement method used in this embodiment are shown. A second configuration example of the measurement apparatus 100 according to the present embodiment is shown together with the measurement target 10 .

<First configuration example of measuring device 100>
FIG. 1 shows a first configuration example of a measurement apparatus 100 according to this embodiment together with a measurement target 10. As shown in FIG. The object 10 to be measured includes a living body. A living body is, for example, a human, a wild animal, a pet, or the like. The measurement device 100 detects a living body included in the measurement object 10 without contact. In addition, the measuring device 100 detects cardiopulmonary activity such as respiration and pulse of the detected living body in a non-contact manner. The measurement device 100 includes a plurality of electrodes 110 , a switching section 120 , a current supply section 130 , a detection section 140 , a calculation section 150 , an information output section 160 and a control section 170 .

The plurality of electrodes 110 are arranged at predetermined intervals at positions away from the object 10 to be measured. FIG. 1 shows an example in which 10 electrodes 110 having substantially the same shape and extending in the Y direction are arranged at equal intervals in the X direction at a position apart from a person lying down in the X direction. It should be noted that the shape of the electrode 110 may not be columnar, and may be plate-like or other shape. In FIG. 1, the electrodes 110 are numbered 1 to 10 in the order in which the electrodes 110 are arranged. For example, the electrode numbered 1 is the first electrode.

A plurality of electrodes 110 constitute a plurality of electrode pairs. Assuming that one electrode pair among the plurality of electrode pairs is a first electrode pair 111 , the first electrode pair 111 applies current toward the measurement target 10 . In other words, the first electrode pair 111 functions as a current applying section that applies a current toward the measurement target 10 at a position away from the measurement target 10 . FIG. 1 shows an example in which the third electrode and the tenth electrode are the first electrode pair 111 .

If an electrode pair different from the first electrode pair 111 among the plurality of electrode pairs is defined as a second electrode pair 112, the second electrode pair 112 detects a potential difference corresponding to the applied current. FIG. 1 shows an example in which the eighth electrode and the ninth electrode are the second electrode pair 112 . A plurality of electrode pairs may be used as the second electrode pair 112 .

The plurality of electrodes 110 are, for example, integrally formed as a detection head section and arranged on the ground surface where a living body may be buried in the ground. Further, the detection head may apply current and detect the potential difference while moving so as to scan the ground surface. In this case, the user of measuring apparatus 100 may move the detection head, or alternatively, the detection head may be self-propelled.

As for the plurality of electrodes 110, the first electrode pair 111 preferably applies a current to a plurality of portions of the measurement object 10, and the first electrode pair 111 detects potential differences generated at a plurality of portions. For example, the first electrode pair 111 applies current to multiple portions of the measurement object 10 as the detection head moves. Alternatively, or in addition to this, by using an electrode pair different from the electrode pair used as the first electrode pair 111 among the plurality of electrodes 110 as the first electrode pair 111, Current may be applied to multiple portions. Thereby, the measuring device 100 can search a wider area of the measurement object 10 and quickly detect whether or not the living body is included in the searched area.

The switching unit 120 connects the first electrode pair 111 among the plurality of electrodes 110 corresponding to the control signal and the current supply unit 130 according to the control signal received from the control unit 170 . The switching unit 120 has, for example, a changeover switch, and connects the first electrode pair 111 designated by the control unit 170 and the current supply unit 130 . Also, the switching unit 120 connects the second electrode pair 112 corresponding to the control signal among the plurality of electrodes 110 and the detecting unit 140 . The switching unit 120 has, for example, a changeover switch, and connects the second electrode pair 112 designated by the control unit 170 and the detection unit 140 .

Current supply unit 130 supplies current to first electrode pair 111 via switching unit 120 . The current supply unit 130 functions as a current source capable of supplying direct current or alternating current, for example. The current supply unit 130 may be capable of supplying a sine wave, square wave, or the like. The detector 140 detects the potential difference between the electrodes of the second electrode pair 112 . The detection unit 140 has, for example, a filter, an amplifier circuit, and an A/D converter, and converts the detected potential difference into a digital signal.

The calculator 150 calculates the impedance of the part to which the current is applied to the measurement object 10 based on the potential difference detected by the detector 140 . The detection unit 140 and the calculation unit 150 continuously detect the potential difference and calculate the impedance.

The information output unit 160 outputs the temporal change in impedance calculated from the potential difference detected by the second electrode pair 112 . The information output unit 160 outputs, for example, the calculated change in impedance as a moving image. In this case, the information output section 160 outputs the time change of the impedance calculated corresponding to the position of the measurement target 10 for each position of the measurement target 10 . Alternatively, the information output unit 160 may output changes in impedance in letters and numbers. The information output section 160 may have a monitor or the like for outputting the measurement results, and may output the measurement results to the outside of the measuring apparatus 100 . Further, the information output section 160 may store the measurement results in a storage section or the like.

If the site to which the current is applied is not a living body, the information output unit 160 outputs an impedance value that hardly changes over time according to the material of the site to which the current is applied. On the other hand, when an electric current is applied to a living body that is carrying out life activities, organs, liquids, gases, etc. with different impedances move in the body, so that an impedance value that changes with time is output. Therefore, the cardiopulmonary activity of the living body can be detected based on the impedance change output by the information output unit 160 . The information output unit 160 may further include a determination unit that determines the cardiopulmonary activity of the living body in response to the amount of change in impedance exceeding the threshold.

The control section 170 controls each section in the measuring device 100 . For example, the control unit 170 supplies a control signal to the switching unit 120 to select an electrode pair to function as the first electrode pair 111 from among the plurality of electrodes 110 . Similarly, the control unit 170 supplies a control signal to the switching unit 120 to select an electrode pair to function as the second electrode pair 112 from among the plurality of electrodes 110 . The control unit 170 also controls the current supply unit 130 to apply current to the measurement object 10 . The control unit 170 controls the detection unit 140, the calculation unit 150, and the information output unit 160, detects the potential difference generated from the measurement target 10, and outputs the change in impedance.

At least part of the calculation unit 150, the information output unit 160, and the control unit 170 is, for example, a CPU or the like. In this case, the measuring device 100 further includes a storage unit. The storage unit stores information output by the information output unit 160 . The storage unit may also store intermediate data generated (or used) by the measuring device 100 in the process of operation, calculation results, threshold values, parameters, and the like. Further, the storage unit may supply the stored data to the request source in response to requests from each unit in the measuring apparatus 100 .

The storage unit may store information such as an OS (Operating System), programs, and the like, in which a computer or the like functions as the calculation unit 150, the information output unit 160, and the control unit 170. FIG. Also, the storage unit may store various information including a database that is referred to when the program is executed. For example, the computer functions as at least part of the calculation unit 150, the information output unit 160, and the control unit 170 by executing programs stored in the storage unit.

The storage unit includes, for example, a ROM (Read Only Memory) that stores a BIOS (Basic Input Output System) of a computer or the like, and a RAM (Random Access Memory) that serves as a work area. The storage unit may also include a large-capacity storage device such as a HDD (Hard Disk Drive) and/or an SSD (Solid State Drive). Also, the computer may further include a GPU (Graphics Processing Unit) or the like.

The measurement apparatus 100 according to the present embodiment described above supplies a current to the measurement target 10, detects the potential difference generated in the measurement target 10, and calculates the impedance of the portion to which the current is supplied. As a result, the measuring apparatus 100 can detect that the living body is performing vital activity at the site to which the current is supplied, in accordance with the fact that the calculated impedance has a temporal change equal to or greater than the threshold. Detection of impedance change by such a measuring device 100 will be described below.

<Simulation of change in impedance>
First, an example of simulating the impedance measurement result of the measuring apparatus 100 according to the present embodiment will be described. The simulation uses a human burial simulation finite element model (hereafter, the burial simulation finite element is abbreviated as FE) that combines a human model composed of 17 human organs, a plurality of electrodes 110, air, and soil. went.

The human FE model generates 512 tomographic images including a person, a plurality of electrodes 110, soil, and air from tomographic image data from the top of the human head to the lower abdomen, and a three-dimensional FE model constructed using the generated tomographic images. is a model. The model has 2,556,572 elements and 522,457 nodes. The human FE model is composed of the organs and substances shown in FIG. 2, and the FE analysis was performed by setting the conductivity for each organ. At this time, respiration and pulse waves were simulated by changing the electrical conductivity of the lung, atrium, and blood stepwise.

The human FE model was constructed with a person having a height of about 170 cm and a weight of about 70 kg. It is a model that contains The plurality of electrodes 110 had a width of 20 mm in the X direction, a thickness of 20 mm in the Z direction, and a length of 470 mm in the Y direction. An air layer of 61 mm is provided between the plurality of electrodes 110 and the ground surface, and the measuring device 100 detects respiratory pulse information in the ground without contact from the ground surface.

The simulation uses the third electrode and the tenth electrode as the first electrode pair 111, then the fourth electrode and the ninth electrode as the first electrode pair 111, and so on, so that the electrode spacing is gradually shortened. A first electrode pair 111, which is a current applying unit, was set. In this embodiment, an example in which the first electrode pair 111 is set in three ways, that is, the third electrode and the tenth electrode, the fourth electrode and the ninth electrode, and the fifth electrode and the eighth electrode will be described.

One electrode pair among the plurality of electrodes 110 positioned between the first electrode pair 111 is used as the second electrode pair 112 for potential difference detection. Here, when there are combinations of two or more electrode pairs between the first electrode pairs 111, all combinations were extracted, and a total of 22 combinations of the first electrode pairs 111 and the second electrode pairs 112 were extracted.

A result of detecting a potential difference generated by the second electrode pair 112 when a constant current of 1 mA is applied from 61 mm above the ground to the first electrode pair 111 for the combination of the first electrode pair 111 and the second electrode pair 112. was calculated, and the amount of impedance change caused by respiration and pulse was further calculated. The number of breaths per minute is 10 times, the pulse rate per minute is 60 times, the lung conductivity during ventilation is 0.1 [S/m], and the cardiac conductivity during pulse is 0.1 [S/m]. m], and the lung conductivity was set to 0.01 [S/m].

FIG. 3 shows a conceptual diagram of the current density distribution calculated by the simulation of this embodiment. FIG. 3 shows a detailed simulation result as a conceptual diagram, showing a tendency of impedance change (in other words, current density distribution) of each part. Since the impedance of a person and the impedance of soil are different, it can be seen that the shape of a person can be detected. From this, it can be seen that although the plurality of electrodes 110 are positioned 61 mm above the ground and are in a non-contact state, current is input into the ground, and the current is concentrated in the human body in particular.

In addition, since human organs also have different conductivities as shown in FIG. 2, it is possible to discriminate the region of some organs such as lungs in the human shape. FIG. 3 is an example conceptually showing changes in impedance in only the lung area, omitting the impedance in other areas. FIG. 3(a) shows the end-inspiration and FIG. 3(b) shows the end-expiration.

It can be seen that the lung region has different impedances at the end-inspiration and end-expiration at different measurement times. This is because the current density decreases due to the maximum content of low-conductivity (high-resistivity) air at the end of inspiration, and the current density increases due to the minimum air content at the end of expiration. it is conceivable that.

Therefore, by measuring the impedance of the measurement object 10 using the measurement device 100, it is possible to detect a living body buried in the ground or the like. Moreover, by measuring changes in the impedance of the measurement object 10 using the measurement device 100, it is possible to determine whether or not the living body is carrying out vital activities. It is desirable that the information output unit 160 be configured to be capable of outputting an image as shown in FIG.

The above simulations were performed with human-buried underground distances of 47 mm, 97 mm, and 146 mm, respectively. When the human-buried underground distance was increased to 97 mm and 146 mm, the current density in the human body tended to decrease compared to the current density when the human-buried underground distance was 47 mm. It is believed that this is because the amount of current flowing in the soil region near the plurality of electrodes 110 increases as the distance increases. However, it was found that the change in lung region current density between end-expiratory and end-inspiratory current densities decreased with increasing distance, but there was a clear change.

FIG. 4 shows an example of the amount of change in impedance calculated in the simulation of this embodiment. FIG. 4 shows the results of calculating the amount of impedance change caused by respiration and pulse for 22 combinations of the first electrode pair 111 and the second electrode pair 112 . From the calculation results, the combination of using the third electrode and the tenth electrode as the first electrode pair 111 and using the fourth electrode and the ninth electrode as the second electrode pair 112 has the maximum impedance change amount of 2.1484 [Ω ] was obtained.

The amount of impedance change caused by human pulse is smaller than the amount of impedance change caused by breathing. In the simulation, the amount of impedance change caused by human pulse was about 1/100 or less of the amount of impedance change caused by breathing. Therefore, it was found that impedance changes due to respiration can also be detected by constructing a highly sensitive potential difference measuring circuit.

Therefore, the measuring device 100 was actually constructed, and electrode non-contact measurement of the breathing and pulse signals of an actual person was performed. A plurality of electrodes 110 were placed on the back side of the bed surface, and measurements were performed on one healthy adult male who was held in a supine position on the bed surface at three human-to-underground burial distances of 40 mm, 90 mm, and 150 mm. For the impedance measurement, a sine wave with a frequency of 225 kHz and an applied current of 0.1 mAp-p was applied. In addition, as a verification, a flow sensor of a medical device was used to simultaneously measure respiration and pulse waveforms for comparison.

The respiratory waveform obtained at a human-to-underground burial distance of 40 mm and the measurement results of the pulse rate measurement device 100 were in good agreement with the measurement results of the flow sensor. Moreover, the measurement results obtained by the measurement device 100 when the human-to-underground burial distance was set to 90 mm were similar to the measurement results obtained by the flow sensor. When the human-to-underground burial distance is set to 150 mm, the measurement results obtained by the measurement device 100 show a decrease in the S/N ratio of the respiratory waveform and an error in the pulse rate, but results corresponding to the measurement results obtained by the flow sensor are obtained. rice field.

As described above, the measuring device 100 of the present embodiment can quickly find a rescued person buried underground in a non-contact manner, and can also detect the vital activity of the rescued person. In this embodiment, an example in which the measuring device 100 detects the potential difference generated from the measurement target 10 has been described, but the present invention is not limited to this. The measurement device 100 may detect an induced magnetic field generated from the object 10 to be measured. Such a measuring device 100 will be described below.

<Detection sensitivity of impedance method and magnetic measurement method>
In the measurement device 100 of the first configuration example shown in FIG. It was explained that non-contact detection can be performed using Here, since it is known that a magnetic field is induced by Maxwell's equations in the lines of electric force based on the potential difference generated in the measurement object 10, the same effect can be expected even if such an induced magnetic field is detected.

Therefore, the theoretical characteristics of the detection sensitivity of the impedance method that detects the impedance from the potential difference and the detection sensitivity of the magnetic measurement method that detects the magnetic field will be described. First, the relationship E(x) between the measured distance using the impedance method and the amount of electrical impedance change can be calculated from Non-Patent Document 1 and the like. In addition, the relationship between the distance measured by the magnetic measurement method and the detection sensitivity is the case where the distance-magnetic field characteristics generated by the heart and lungs when current is applied to a person buried in the ground is derived from a linear current (hereinafter referred to as the _B1 characteristic ) and the case of circular current ₍ hereinafter referred to as B2 characteristic).

_{The B1} characteristic and the B2 characteristic are calculated as follows. where B ₁ (x) and B ₂ (x) are the magnetic flux densities [T], μ ₀ is the magnetic constant (=4π×10 ^-7 [H/m]), x is the distance [cm], and I is the current (=1 [mA]), r indicates the radius of the circular current (=1 [cm]).

FIG. 5 shows the relationship between the measurement distance and the detection sensitivity in the impedance method and the magnetic field measurement method used in this embodiment. The detection sensitivity was defined as the amount of change in potential or magnetic field per unit distance and current, and was normalized by setting the calculated value at a distance of 1 cm from the center of the electrode, wire or coil to 1. From FIG. 5, it can be seen that the E(x) characteristic, which indicates the characteristic using the electrical impedance method, sharply decreases in detection sensitivity as the measurement distance increases. On the other hand, it can be seen that the _B1 characteristic and B2 characteristic, which _are considered to be characteristics using magnetic field measurement, show little decrease in detection sensitivity in the deep direction where the measurement distance is large.

FIG. 6 shows the results of sensitivity comparison between the impedance method and the magnetic field measurement method used in this embodiment. FIG. 6 shows the results calculated using the same conditions as those used in the human FE model. At a human-underground burial distance of 47 mm, when the E ₍ x) characteristic, which is the relationship between the measured distance using the impedance method and the electrical impedance change amount, is used as a reference, the _B1 characteristic and the B2 characteristic are about 100 times and about 40 times, respectively. The difference in sensitivity was doubled. Similarly, at a distance of 97 _mm , the _B1 characteristic and B2 characteristic increased 860 times and 175 times, and at a distance of 146 mm, they increased about 2980 times and about 406 times. Next, the configuration of the measuring apparatus 100 using the magnetic field measuring method capable of such highly sensitive measurement will be described.

<Second Configuration Example of Measuring Device 100>
FIG. 7 shows a second configuration example of the measurement device 100 according to this embodiment together with the measurement object 10 . In the measuring apparatus 100 of the second configuration example, the same reference numerals are assigned to the operations that are substantially the same as those of the measuring apparatus 100 of the first configuration example shown in FIG. 1, and overlapping descriptions are omitted. The measurement device 100 of the second configuration example further includes a magnetic field detection element 210 .

A first electrode pair 111 , which is a current applying section, applies an alternating current toward the measurement target 10 at a position away from the measurement target 10 . In the case of the magnetic field measurement method, the current applying section preferably applies an alternating current to the measurement target 10 in order to efficiently generate an induced magnetic field. For example, the current applying section applies an alternating current with a frequency of about 10 kHz or higher toward the object 10 to be measured. Moreover, it is desirable that the current applying section applies an alternating current to a plurality of portions of the object 10 to be measured.

The magnetic field detection element 210 detects an induced magnetic field generated from the measurement target 10 in response to alternating current. The magnetic field detection element 210 is desirably a highly sensitive magnetic sensor. For example, high-sensitivity magnetic sensors include magneto-impedance sensors, fluxgates, optically pumped atomic magnetic sensors, diamond quantum sensors, and the like. Also, a plurality of magnetic field detection elements 210 may be provided.

The detection unit 140 converts the detection result of the magnetic field detection element 210 into a digital signal. The calculation unit 150 calculates the magnitude of the magnetic field at the site to which the current is applied to the measurement object 10 based on the digital signal output by the detection unit 140 . The detection unit 140 and the calculation unit 150 continue to convert the detection result into a digital signal and to calculate the magnetic field.

The information output unit 160 outputs information indicating temporal changes in the detection result of the induced magnetic field by the magnetic field detection element 210 , corresponding to temporal changes in the measurement object 10 . The information output unit 160 outputs, for example, the calculated change in the magnitude of the magnetic field as a moving image. In addition, the information output unit 160 may emphasize and output a portion where the change in the magnitude of the magnetic field exceeds the threshold. When the current applying unit applies an alternating current to a plurality of portions of the measurement object 10, the information output unit 160 outputs temporal changes in the detection result of the induced magnetic field by the magnetic field detecting element 210 for each of the plurality of portions. may

As described above, the measurement apparatus 100 of the second configuration example can measure the measurement target 10 with higher sensitivity by using the magnetic field detection element 210 instead of the second electrode pair 112 that detects the potential difference. Note that the measurement device 100 of the second configuration example may further perform measurement by the impedance method using the second electrode pair 112 .

The measuring device 100 may combine the measurement by the impedance method and the measurement by the magnetic field measurement method. For example, the magnetic field measurement method is used for measurement of the measurement target 10 that is more than the threshold, and the impedance method is used for measurement of the measurement target 10 that is less than the threshold. Thereby, the measuring device 100 can measure a wider area with the same degree of measurement sensitivity.

Moreover, the measurement apparatus 100 may perform measurement by the impedance method and measurement by the magnetic field measurement method on the same measurement target 10 . Measuring apparatus 100 can output a more reliable measurement result by comparing two measurement results obtained by different measurement methods. Furthermore, the measuring apparatus 100 may simultaneously perform the potential difference detection of the second electrode pair 112 and the magnetic field detection of the magnetic field detection element 210 to shorten the measurement time. Alternatively, the change in impedance due to respiration may be measured by the impedance method, and the change in the induced magnetic field due to pulse may be measured by the magnetic field measurement method. As a result, the measuring device 100 can measure respiration and pulse with the same level of measurement sensitivity.

Although the measurement apparatus 100 according to the present embodiment has been described as an example in which the first electrode pair 111 serving as the current applying section is selected from among the plurality of electrodes 110, the present invention is not limited to this. The measuring device 100 may have only one first electrode pair 111 as a current applying section. Also, the measuring device 100 may have only one second electrode pair 112 for potential difference detection. Alternatively, the second electrode pair 112 may be omitted if the measuring device 100 is a device that performs magnetic field measurements only.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist thereof. be. For example, all or part of the device can be functionally or physically distributed and integrated in arbitrary units. In addition, new embodiments resulting from arbitrary combinations of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment caused by the combination has the effect of the original embodiment.

10 measurement object 100 measuring device 110 electrode 111 first electrode pair 112 second electrode pair 120 switching unit 130 current supply unit 140 detection unit 150 calculation unit 160 information output unit 170 control unit 210 magnetic field detection element

Claims (5)

a current applying unit that applies an alternating current toward the object to be measured at a position away from the object to be measured;
a magnetic field detection element that detects an induced magnetic field generated from the object to be measured according to the alternating current;
and an information output unit that outputs information indicating a temporal change in the detection result of the induced magnetic field by the magnetic field detection element, corresponding to the temporal change in the measurement target. The current applying unit applies the alternating current to a plurality of portions of the object to be measured,
The information output unit outputs temporal changes in detection results of the induced magnetic field by the magnetic field detection element for each of a plurality of portions.
The measuring device according to claim 1. The measuring device according to claim 1 or 2, wherein said current applying section applies said alternating current with a frequency of 10 kHz or higher toward said object to be measured. The current applying unit has a plurality of electrode pairs,
applying a current from a first electrode pair of the plurality of electrode pairs toward the object to be measured;
detecting a potential difference corresponding to the applied current using a second electrode pair different from the first electrode pair;
The information output unit further outputs a temporal change in impedance calculated from the potential difference detected by the second electrode pair.
4. The measuring device according to any one of claims 1-3. applying an alternating current toward the object to be measured at a position away from the object to be measured;
detecting an induced magnetic field generated from the measurement object in response to the plurality of alternating currents;
and outputting information indicating a temporal change in a detection result of the induced magnetic field corresponding to the temporal change in the measurement object.

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