115results about "Magnetic field offset compensation" patented technology

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 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.

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 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.

[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.

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.

To provide systems and methods for mapping magnetic fields by visualizing the magnetic field.SOLUTION: The system is configured to utilize a high-sensitivity magnetic field sensor 6 (for example, a magnetometer 12 disposed inside a tube 16 made of magnetic shielding material) disposed on one side of a magnetic field modulation screen 2 to acquire measurement data representing an image of a magnetic field. The magnetic field modulation screen includes a plurality of magnetic field-generating pixel elements (for example, current-carrying loops made of a magnetic field generating material). As an arbitrary configuration, the system is configured to enable reduction in an amount of measurement data required to reconstruct an image of the original magnetic field by using compressive sensing techniques. Compressive sensing is enabled so that an electric current is not supplied to the different pixel element to be selected in consecutive sampling time of the magnetic field-generating pixel elements of the magnetic field modulation screen.SELECTED DRAWING: Figure 3B

A magnetism measurement device according to the present invention includes: a first magnetic sensor (An) that detects magnetism acting along a first direction, the first direction being chosen arbitrarily; a second magnetic sensor (Bn) that detects magnetism acting along a second direction, the second direction crossing the first direction along which the first magnetic sensor detects magnetism; and a magnetic-field generating part (Cn) that generates a magnetic field in response to a flow of current. The magnetic-field generating part (Cn) is incorporated such that magnetism act along the first direction and the second direction in response to a flow of current in a state where the positions thereof facing the first magnetic sensor (An) and the second magnetic sensor (Bn) are fixed.

The present invention provides a magnetic sensor capable of eliminating the AC component contained in an ambient magnetic field. The magnetic sensor (1) comprises: an ambient magnetic field sensor (S0) that generates an ambient magnetic field signal (F0), a detection magnetic field sensor (S1) that generates a detection magnetic field signal (F1), a capacitor (C) that extracts the DC component by removing the AC component of a predetermined frequency band from the ambient magnetic field signal (F0), a compensation coil (31) that applies magnetic field elimination to the detection magnetic field sensor (S1) based on the DC component, a compensation coil (41) that applies magnetic field elimination to the detection magnetic field sensor (S1) based on the detection magnetic field signal (F1), and a bandpass filter (91) that removes at least the AC component of a predetermined frequency band from the detection magnetic field signal (F1). Thus, the AC component contained in the ambient magnetic field can be eliminated regardless of the positions of the ambient magnetic field sensor and the detection magnetic field sensor.

An embodiment of the present invention relates to a subassembly for a sample compartment of a spectrometer. The subassembly includes a sample support adapted to support one or more sample holders for use in the sample compartment. The sample support is associated with one or more magnets. The subassembly further includes a sensor assembly configured to detect the one or more magnets associated with the sample support to identify a mode of operation of the spectrometer corresponding to the sample support.

A magnetic sensor is provided with a support member having an inclined surface inclined with respect to a reference plane, and a magnetic detection element structure. The magnetic detection element structure has a lower surface at least partially facing the inclined surface, an upper surface on the opposite side from the lower surface, a first surface connecting the lower surface and the upper surface and including a plurality of steps, and a lower electrode including the lower surface. And a magnetic detection element disposed on the lower electrode, the upper surface of the magnetic detection element constituting the upper surface of the magnetic detection element structure. The lower electrode has a first side surface forming a part of the first surface. The first side surface is inclined with respect to a direction perpendicular to the inclined surface.

A probe (303; 403) for sensing a magnetic marker, comprising a first coil set (313; 413) including a first coil of a first coil type, e.g., a sense coil (305; 405), disposed between a first pair of coils of a second coil type, e.g., a drive coil (301a, 301b; 401a, 401b) connected in series, and a balance element (317; 417) axially spaced from the first coil set (313; 413) along the length of the probe (303; 403). The balance element (317; 417) is configured or arranged to generate a sense voltage that fully offsets, partially offsets, or minimizes a sense voltage induced in one or more sense coils (305; 405) of the first coil set from the drive coil or coils (301a, 301b; 401a, 401b). A detection system is also disclosed, comprising the probe (303; 403), a magnetic field generator configured to drive an alternating magnetic field through the drive coils (301a, 301b; 401a, 401b) of the first coil set and the balance element (317; 417), and at least one detector configured to receive a signal indicative of a sensed voltage.

A magnetoresistive sensor with harmonically broadened linear range comprises a substrate (100) and a multiple push-pull magnetoresistive sensing bridge arms. The push arms (91) of the sensing bridge comprise N types of push magnetoresistive sensing units (94). The pull arms (92) comprise N types of pull magnetoresistive sensing units. Key characteristic parameters of each magnetoresistive sensing unit comprise R0i, MRi, Hsi, ±αpi and ai. The Key characteristic parameters of the push magnetoresistive sensing units (94) and corresponding pull magnetoresistive sensing units are different from the key characteristic parameters of standard magnetoresistive sensing unit of a standard push-pull linear magnetoresistive sensor. There is at least one set of key characteristic parameters [(R0j, MRj, Hsj, ±αpj), aj]. Linear parts and nonlinear harmonic parts of R-H characteristic parameters that characterize the push magnetoresistive sensing units and the pull magnetoresistive sensing units are superimposed, so that the linear range of the multiple push-push magnetoresistive sensing bridge is greater than the linear range of the standard push-pull linear magnetoresistive sensor.

A magnetic sensor includes a first MR element and a second MR element, and a first magnetic field generator and a second magnetic field generator. Each of the first magnetic field generator and the second magnetic field generator includes a ferromagnetic portion and an antiferromagnetic portion to be exchange-coupled with the ferromagnetic portion. The first magnetic field generator is configured to generate a first magnetic field including a first component in a first direction, and to apply the first component to the first MR element. The second magnetic field generator is configured to generate a second magnetic field including a second component in a second direction, and to apply the second component to the second MR element.

The invention relates to a method for calibrating a magnetometer using a magnetic field source arranged at a distance from the magnetometer in a predetermined pose, comprising the following steps: receiving a measurement signal from the magnetometer while the magnetic field source generates a predetermined reference magnetic field, Calculating a ground-truth measurement signal that would correspond to a magnetometer measurement signal if the magnetometer alone measured the reference magnetic field, based on the predetermined pose and the predetermined reference magnetic field. Calibrating the magnetometer based on the measurement signal and the ground truth measurement signal. The invention relates to a device, a system for calibrating a magnetometer, a computer program and a machine-readable storage medium.

A magnetic sensor includes at least one MR element and a coil. The coil includes at least one conductor portion. The at least one conductor portion is each located at a position such that a partial magnetic field generated by the conductor portion is applied to one of the at least one MR element, the one corresponding to the conductor portion, and extends along an imaginary curve curving to protrude in a direction away from the corresponding MR element.

The invention discloses a transient electromagnetic detection device based on a GMI weak magnetic probe array, and belongs to the technical field of geophysical detection. Comprising a transmitting device, the transmitting device comprises a transmitting coil and a transmitting coil current driving module, and the transmitting coil is connected with a signal control and data processing device through the transmitting coil current driving module; the receiving device comprises a GMI weak magnetic probe array, compensation coils and a compensation coil current driving module, the multiple compensation coils are coaxially and uniformly arranged in the transmitting coil along the circumferential side, the compensation coils tightly surround the outer side of the GMI weak magnetic probe array, the compensation coils are connected with the compensation coil current driving module, and the compensation coils are connected with the GMI weak magnetic probe array. The GMI weak magnetic probe array and the compensation coil current driving module are connected with the signal control and data processing device, and the transmitting coil current driving module is connected with the compensation coil current driving module. According to the invention, the secondary magnetic field is directly measured through the GMI weak magnetic probe array and the active field offset technology, and the shallow resolution and the anti-interference capability are improved.

A magnetic field detection sensor with: a magnetic impedance element designed to exploit a magnetic impedance effect; a bias coil designed to apply a bias field to the magnetic impedance element; an oscillator circuit designed to apply an alternating current to the magnetic impedance element; a differentiating circuit designed to differentiate an output signal of the magnetic impedance element; a flip-flop circuit configured to output a high-level signal and a low-level signal based on a trigger signal output by the differentiating circuit; and a computing unit configured to detect an external magnetic field based on a time course with high and low of the high-level signal and low-level signal output by the flip-flop circuit, wherein the magnetic field detection sensor is configured to detect the external magnetic field based on an output signal obtained by applying the alternating current to the magnetic impedance element, the magnetic impedance element comprises a non-magnetic substrate and a magnetic layer provided on a surface of the non-magnetic substrate, wherein a magnetic field detection direction coincides with a longitudinal direction of the magnetic impedance element and the magnetic layer is configured to have magnetic anisotropy such that a direction of an axis of its easy magnetizability coincides with the magnetic field detection direction, and The computing unit is configured to send a reset signal to the flip-flop circuit at the time of a drop in an AC bias frequency, and to detect the external magnetic field based on the duration of an initial high-level signal following the reset signal.

This disclosure describes a sensor chip for calibration and its associated lead frame. The present disclosure relates to a packaged sensor chip (100) having: a lead frame (20) on which a sensor element (10) is mounted, designed to generate a sensor signal dependent on a magnetic field experienced by the sensor element; and a housing (30) for this purpose. The lead frame has functional terminals (40) having at least two calibration terminals (T1, T2, COM) arranged on opposite sides of the housing. The lead frame has a conductive structure (60) connecting the at least two calibration terminals, the conductive structure being configured to generate a calibration magnetic field for the sensor element when current flows through it. The conductive structure is part of a connection structure (50, 60) connecting the multiple lead frames before they separate from each other along a first direction (the other two opposite sides are opposite each other along the first direction).