206results about "Magnetic field offset compensation" patented technology

The present disclosure provides a method for optimizing a broadband noise of an inductive magnetic field sensor as well as a magnetic field sensor, including: determining a functional relationship between an induced voltage of a coil and an effective permeability of a magnetic core of the inductive magnetic field sensor; determining an equivalent voltage noise expression of a temperature variation-induced permeability noise of the magnetic core according to the functional relationship; determining a key influencing factor of the magnetic core according to the equivalent voltage noise expression of the temperature variation-induced permeability noise of the magnetic core; modifying the magnetic core according to the key influencing factor of the magnetic core to optimize the temperature variation-induced permeability noise of the magnetic core; and constructing a dual-channel composite multi-stage modulation signal-noise separation circuit to optimize a low-frequency band noise and a high-frequency band noise of the inductive magnetic field sensor.

A magnetometer with responsive material is provided that includes a PT symmetric assembly. The PT symmetric assembly includes gain material and responsive material that are positioned to achieve PT symmetry. The responsive material is configured to shift a resonance frequency of point defects in response to a magnetic field. A microwave antenna is configured to generate a microwave field of varying frequencies that engage the responsive material. A controller is configured to adjust a tunable laser source that is input into the PT symmetric assembly based on an output of the PT symmetric assembly to cause a gain generated by the gain material to match a loss caused by the responsive material. The controller is further configured to determine a strength of the magnetic field by determining one of a deviation from the exceptional point and an amplitude of the gain needed to reach the exceptional point.

In described examples, an integrated circuit (IC) written on a substrate that includes a substrate surface includes a magnetic concentrator, a Hall sensor, a primary coil, and a secondary coil. The Hall sensor at least partially overlaps the magnetic concentrator. The primary coil at least partially overlaps the magnetic concentrator. The secondary coil at least partially overlaps the magnetic concentrator and the primary coil, and surrounds the Hall sensor.

The present disclosure relates to a method (100) of magnetically calibrating a magnetometer sensing system (30) with respect to an electronic device (50), the method (100) comprising: detecting (110) a disturbing magnetic source (520) in the electronic device (50) relative to a reference coordinate system (X, Y, Z) of the magnetometer sensing system (30); identifying (120) one or more magnetometers (Sk,l) of the magnetometer sensing system (30) which are magnetically affected by the detected disturbing magnetic source (520); selecting (130) one or more balancing magnetic sources (400) to reduce a magnetic effect of the detected disturbing magnetic source (520) on the one or more identified magnetometers (Sk,l); and placing (140) the one or more selected balancing magnetic sources (400) in a fixed relation to the magnetometer sensing system (30) and / or to the disturbing magnetic source (520).

The technical problem of the present invention is to provide a magnetic detection system capable of detecting metal foreign matters with high sensitivity. As a technical means for solving the technical problem, a magnetism detection system (100) is provided with: a signal generation circuit (501) that generates an excitation signal (P); an excitation coil (250) to which an excitation signal (P) is supplied; a buffer circuit (503) connected between the signal generation circuit (501) and the excitation coil (250); magnetic sensors (40A, 40B) that are disposed on opposite sides of each other in the coil axis direction when viewed from the excitation coil (250); a sample stage (300) that holds a sample (310) between the excitation coil (250) and the magnetic sensor (40A); and a detection circuit that generates a detection signal (OUT) on the basis of the difference between the output signals (Pa, Pb) output from the magnetic sensors (40A, 40B). As a result, it is possible to suppress a disorder in the waveform of the excitation signal (P) by means of the snubber circuit (503), and thus it is possible to detect a metal foreign object with high sensitivity.

The application discloses a method for improving low-frequency precision of an atomic magnetometer, and relates to the technical field of weak magnetic detection. In the method, the closed-loop atomic magnetometer is in a zero-locking state, a direct-current bias system is automatically and accurately adjusted, the atomic magnetometer is caused to work in a critical interval between a zero-locking region and a linear region, the zero-locking region has the suppression on low-frequency magnetic noise, and the linear region has a higher response to a measured magnetic field, so that the low-frequency measurement precision of the atomic magnetometer is improved. The application is suitable for an optical pumping atomic magnetometer system, and is favorable for improving the precision and stability of the atomic magnetometer, and can significantly improve the magnetic field sensitivity in the low-frequency part.

A system, comprising: a sensing element including a plurality of resistive elements; a switching matrix that is configured to change a total resistance of the sensing element by bringing online or offline one or more of the plurality of resistive elements, the total resistance of the sensing element, at any point in time, being based on respective resistances of only those of the plurality of resistive elements that are currently online; a matrix controller that is configured to detect when a value of a counter signal is updated and cause the switching matrix to change the total resistance of the sensing element by bringing offline or online one or more of the plurality of resistive elements based on the value of the counter signal; and a counter signal generator configured to detect whether an offset signal satisfies a predetermined condition and update the value of the counter signal.

Disclosed is an open-structured RF transmitting and receiving coil system including: a magnetic field generation part configured to generate a magnetic field to detect the position of magnetic particles located in a three-dimensional space; a detection part configured to receive a reflection signal from the magnetic particles receiving the magnetic field; and a cancellation part connected to the detection part and including a calibration coil.

A fully integrated micro search coil magnetometer (μSCM) with a low-noise instrumentation amplifier is provided for low-frequency magnetic field measurements in the range of 1Hz to 1kHz. A micro search coil formed by stacking planar spiral inductors and serially connecting them with an in-phase configuration is used for magnetic field measurements. The critical line width and inner diameter of a planar spiral inductor are theoretically calculated and experimentally verified, enabling the development of a unique CMOS layout. This layout incorporates the calculated critical inner diameter, significantly optimizing the area utilization on the CMOS die. Additionally, the CMOS die includes a polysilicon-layer inductor for on-chip calibration, a Hall effect sensor for DC magnetic field measurement, and a temperature sensor for enhanced functionality. The μSCM delivers a compact, energy-efficient, and highly sensitive solution for low-frequency magnetic field measurements, surpassing the performance of most commercially available Hall effect sensors.

The present disclosure provides magnetic sensor system that includes a magnetic sensing device comprising a magnetic multi-turn sensor, and a method of initializing the magnetic multi-turn sensor into a known state with a defined domain wall configuration ready for use. A strong magnetic field is first applied to fill the MT sensor with domain walls. A current is then applied to a domain wall stopping structure arranged over at least one portion of the MT sensor, and the working magnetic field (i.e., the magnetic field generated by a magnet mounted on the mechanical system) is rotated until the desired domain wall configuration is achieved. Once the desired domain wall configuration is achieved, the current applied to the domain wall stopping structure is stopped and the MT sensor is ready for use. The sensor can be initialized into a known state without needing to drive the mechanical system to a start or end position.

This application relates to a position detection device, comprising: a first Hall element; a second Hall element; a differential amplifier configured to generate a differential voltage by differentially amplifying a first Hall voltage generated by the first Hall element and a second Hall voltage generated by the second Hall element; a summing amplifier configured to generate a summed voltage by summing the first Hall voltage and the second Hall voltage; a comparator configured to compare a reference voltage with the differential voltage to generate an error voltage; and a current converter configured to generate a bias current supplied to the first Hall element and the second Hall element based on the error voltage, wherein the device is configured to detect the position of a detected object based on the summed voltage.

The present application provides a magnetic field sensor and a multi-axis magnetic field sensor, and relates to the field of magnetic field measurement technology. The magnetic field sensor comprises: a magnetic flux conversion module, a magnetic induction module, and a differential detection module. The magnetic flux conversion module comprises: a magnetic field input area, a magnetic field output area, a magnetic flux direction conversion area, and a magnetic flux path connection area. The magnetic flux conversion module concentrates and amplifies a magnetic field to be measured in the magnetic field induction direction and converts it into a magnetic field component in a spatial solid angle direction with an angle of 0-90 degrees with the direction of the magnetic field to be measured. The magnetic induction module senses the magnetic field at the air gap of the magnetic flux conversion module, generates a differential voltage signal, and forms an output electrical signal to be measured through the differential detection module. This enables the conversion of the magnetic field to be measured into a magnetic field component in the opposite direction at the air gap, thereby realizing differential detection of a push-pull bridge structure using magnetic induction modules with the same sensitivity direction. It can be manufactured in an integrated manner, leading to a simple process and good sensitivity consistency, and it is easy to produce.

Disclosed in the embodiments of the present invention is a magnetic tunnel junction signal isolator with electric shielding layer. In the isolator, a coil is located between a magnetic shielding layer and an electric shielding layer; the electric shielding layer is located between the coil and a magnetoresistive sensor, the magnetoresistive sensor is composed of a plurality of magnetic tunnel junctions that are connected in a series-parallel way. The two ends of the coil are electrically connected to a circuit having a first reference ground used to send a signal; a signal is sent from the magnetoresistive sensor to a receiving circuit connected to a second reference ground. The magnetic shielding layer is electrically connected to the first reference ground in a single-point or multi-point mode, or it is completely electrically isolated from the first reference ground. The electric shielding layer may instead be electrically connected to the second reference ground in a single-point or multi-point mode, or it may be completely electrically isolated from the second reference ground. Or, the electric shielding layer and magnetic shielding layer are respectively electrically connected to any potential or potentials between the first reference ground and the second reference ground in a single-point or multi-point mode. The embodiments of the present invention, prevent the electric field from corrupting the magnetoresistive sensor signal, as such solving the problem of interference and damage caused to a magnetic tunnel junction in the magnetoresistive sensor by the coil.

To reduce detection error of a magnetic sensor with a simple method.SOLUTION: A magnetic sensor device 100 comprises a magnetic sensor 1, a magnetic field generator 70, and a processor 2. The processor 2 is configured to generate: a first sensitivity which is a sensitivity of the magnetic sensor 1 when the intensity of additive magnetic field is changed within a first range; a second sensitivity which is a sensitivity of the magnetic sensor 1 when the intensity of additive magnetic field is changed within a second range; and a detection value corresponding to a magnetic field component which is a component of an object magnetic field in a predetermined direction on the basis of a detection signal, the first sensitivity and the second sensitivity.SELECTED DRAWING: Figure 14

A sensor, comprising: a first signal path including a plurality of magnetoresistance (MR) elements, the first signal path being configured to generate a first signal based, at least in part, on an output of the MR elements, the output of the MR elements being generated, at least in part, in response to an external magnetic field that is incident on the sensor and a first feedback magnetic field; a second signal path including one or more Hall elements, the second signal path being configured to generate a second signal based, at least in part, on an output of the Hall elements; a first feedback coil that is configured to generate the first feedback magnetic field, the first feedback coil being driven with a first drive current, the first drive current being generated, at least in part, based on the first signal.

A sensor, comprising: a first signal path including a plurality of magnetoresistance (MR) elements, the first signal path being configured to generate a first signal based, at least in part, on an output of the MR elements, the output of the MR elements being generated, at least in part, in response to an external magnetic field that is incident on the sensor and a first feedback magnetic field; a second signal path including one or more Hall elements, the second signal path being configured to generate a second signal based, at least in part, on an output of the Hall elements; a first feedback coil that is configured to generate the first feedback magnetic field, the first feedback coil being driven with a first drive current, the first drive current being generated, at least in part, based on the first signal.

A directional tool and a method of surveying a wellbore with the directional tool in a borehole string are provided. A first sensor of the directional tool is disposed in a non-uniform ambient magnetic field. A first applied magnetic field is applied to the first sensor. A first measurement is obtained at the first sensor while the first sensor is disposed in the non-uniform ambient magnetic field and the first applied magnetic field is applied. A second applied magnetic field is applied to the first sensor. A second measurement is obtained at the first sensor while the first sensor is disposed in the non-uniform ambient magnetic field and the second applied magnetic field is applied. The directional tool is calibrated based on the first measurement and the second measurement. Downhole survey measurements are obtained in the wellbore with the calibrated directional tool.

Various embodiments disclosed herein comprise a system. The system comprises a coil, a magnetic field sensor, and a controller. The coil generates a spatially and temporally varying magnetic field. The magnetic field sensor measures the magnetic field and a background magnetic field. The magnetic field sensor provides a magnetic field measurement and a background magnetic field measurement to the controller. The controller determines the position and orientation of the magnetic field sensor based on the magnetic field measurement and the background magnetic field measurement. The controller transfers control signaling to modify the magnetic field based on the position and orientation of the magnetic field sensor to null the background magnetic field. The coil receives the control signaling and modifies the spatially and temporally varying magnetic field based on the control signaling to null the background magnetic field.

A method for making an axial magnetic field measurement in a downhole tool includes evaluating an axial magnetic field measurement to determine a magnetic disturbance offset and removing the magnetic disturbance offset to obtain a compensated axial magnetic field measurement.

A method includes receiving, from a sensor proximate a first conductor, a sensor signal representing a measurement of a magnetic field produced by a first current flowing in the first conductor and a second current flowing in a second conductor. The first current includes first and second current components having different frequencies, and the second current includes third and fourth current components. The third current component is phase shifted from, and has the same frequency as the first current component. The fourth current component has a different frequency from the third current component. The method also includes determining reference values of the first and second currents, and, based on the sensor signal and the reference values of the first and second currents, determining for the sensor, a plurality of coupling coefficients representing magnetic field coupling between the first and second conductors.

A magnetic field detection apparatus includes a magnetoresistive effect element and a helical coil. The magnetoresistive effect element includes a magnetoresistive effect film extending in a first axis direction. The helical coil includes a parallel connection including first and second parts extending in a second axis direction inclined with respect to the first axis direction. The first and second parts are adjacent to each other in a third axis direction and coupled to each other in parallel. The helical coil is wound around the magnetoresistive effect element while extending along the third axis direction. The magnetoresistive effect film overlaps the first and second parts in a fourth axis direction orthogonal to the second and third axis directions. The helical coil is configured to be supplied with a current and thereby configured to generate an induction magnetic field to be applied to the magnetoresistive effect film in the third axis direction.

[Problem] To prevent damage to an external magnetic body for collecting magnetic flux to a magnetosensitive element in a magnetic sensor provided with the external magnetic body. [Solution] A magnetic sensor 100 comprises: a sensor chip 20 having an element-forming surface 21 on which magnetosensitive elements R1 to R4 are formed; an external magnetic body 30 having an end surface 33 which is positioned at a distal end in a longitudinal direction and which faces the element-forming surface 21, and side surfaces 34 to 36 configuring an outer peripheral surface of a cross section perpendicular to the longitudinal direction; and a protective resin 4 covering at least a portion of the element-forming surface 21 and the side surfaces 34 to 36 of the external magnetic body 30. It is thus possible to prevent damage to the sensor chip 20 and the external magnetic body 30 even if an impact is imparted from the outside.

The present invention relates to a magnetic sensor device with a substrate (10) having a substrate surface (10a), at least one first measuring bridge (12a) each with first magnetoresistive elements (14a), by means of which a first measured quantity with respect to a first magnetic field strength can be determined in a first sensing direction running parallel to the substrate surface (10a), which is parallel to a respective first magnetization direction of the reference positions (18) of the first magnetoresistive elements (14a), and at least one soft magnetic shielding element (26a, 26b), wherein at least one of the first magnetoresistive elements (14a) has a magnetic vortex (28) in its free position (16) or, in the case of at least one of the first magnetoresistive elements (14a), its free position (16) is located between a first hard magnetic area and a second hard magnetic area.The present invention also relates to a manufacturing method for a magnetic sensor device.

Disclosed herein is a magnetic sensor that includes a housing, a magnetic sensor module accommodated in the housing, and an insulating dummy substrate. The magnetic sensor module including: an insulating substrate having upper and lower surfaces; a sensor chip mounted on the upper surface of the substrate; a terminal electrode provided on the upper surface of the substrate; a wiring pattern provided on the lower surface of the substrate; a first through hole conductor penetrating the substrate and connecting one end of the wiring pattern and the terminal electrode; and a second through hole conductor penetrating the substrate and connecting another end of the wiring pattern and the sensor chip. The dummy substrate is disposed between an inner wall of the housing and the lower surface of the substrate.

To provide a magnetic detection system capable of detecting a metallic foreign object with high sensitivity. A magnetic detection system 100 includes: a signal generation circuit 501 that generates an excitation signal P; an excitation coil 250 to which the excitation signal P is supplied; a buffer circuit 503 that is connected between the signal generation circuit 501 and the excitation coil 250; magnetic sensors 40A and 40B that are disposed on opposite sides of the excitation coil 250 along the coil axis direction; a sample stage 300 that holds a sample 310 between the excitation coil 250 and the first magnetic sensor 40A; and a detection circuit that generates a detection signal OUT based on the difference between output signals Pa and Pb output respectively from the magnetic sensors 40A and 40B. With this configuration, the buffer circuit 503 suppresses waveform distortion of the excitation signal P, thereby enabling detection of a metallic foreign object with high sensitivity.

The magnetic sensor includes at least one MR element and at least one magnetic field generator configured to generate a bias magnetic field. The at least one magnetic field generating body has a first end portion and a second end portion, and includes a first portion including the first end portion and a second portion including the second end portion. The film thickness in the first portion is greater than the film thickness in the second portion. The at least one MR element has a third end portion and a fourth end portion, and is configured such that an interval between the first end portion and the third end portion is smaller than an interval between the second end portion and the fourth end portion.

To maintain measurement sensitivity and reduce the amount of computation in a sensitivity measurement method of a magnetic sensor.SOLUTION: Provided is a sensitivity measurement method of a magnetic sensor comprising a sensor chip 20 having a magnetism-sensitive element, magnetism collecting bodies 30, 40 for collecting a magnetic field in the sensor chip 20, and a casing for housing the sensor chip 20 and the magnetism collecting bodies 30, 40. The method comprises the steps of: applying a magnetic field to a magnetic sensor 1; and calculating the sensitivity of the magnetic sensor on the basis of a simple average of theoretical magnetic field strength in multiple virtual sensitivity points P uniformly and dispersedly disposed inside the casing and an output value outputted from the sensor chip.SELECTED DRAWING: Figure 10

A probe for locating magnetic markers used in surgery. The probe includes: at least two first coils (3a, 3b) and at least one second coil (5), which are arranged substantially coaxially on the longitudinal axis of the probe for measuring the proximity of the magnetic marker to the probe; and a reference voltage balancing device (7) comprising a first elongated conductor defining a conductive path extending partially around the probe axis. The conductive path is configured and arranged such that, in use, a balancing magnetic field induces a balancing voltage in the sensing coil that at least partially cancels out the reference voltage. Methods for manufacturing such a probe, methods for setting such a probe for sensing magnetic markers, and detection devices for locating magnetic markers during surgery are also disclosed.

The present application relates to the field of magnetic sensing chip detection, and provides a kind of magnetic sensing chip sensitivity temperature drift testing device and testing method.The device includes: temperature box, temperature drift testing module and signal acquisition module, the temperature drift testing module is arranged in temperature box, and the signal acquisition module is connected with the temperature drift testing module;The temperature drift testing module includes m magnetic field generating modules, each magnetic field generating module includes permanent magnet holder and multiple permanent magnets, the permanent magnet holder is provided with the through hole for accommodating the magnetic sensing chip to be measured and standard magnetic sensing chip, and multiple permanent magnets are placed in the permanent magnet holder on both sides of the through hole;The signal acquisition module has m channels, for simultaneously collecting the output signal of the magnetic sensing chip to be measured and standard magnetic sensing chip corresponding to m magnetic field generating modules.By the present application, the sensitivity temperature drift test of linear magnetic sensitive sensing chip can be realized at low cost and high efficiency.