Patent classifications
G01R33/025
METHOD AND APPARATUS FOR SUPPRESSING AT LEAST ONE OF AN ELECTRIC OR A MAGNETIC FIELD EMITTED DURING MAGNETIC RESONANCE RECORDINGS
According to one or more example embodiments, a computer-implemented method for at least partially suppressing a field emitted by a magnetic resonance device during an examination, the emitted field being at least one of an electric field or a magnetic field, the method comprises measuring a signature of the emitted field with a sensor facility; providing a trained function which is configured, based on a signature to generate a field information item relating to the emitted field upon which the respective signature is based; creating a field information item for the emitted field by inputting the signature into the trained function; and suppressing the emitted field by generating a counterfield with a transmitting facility based on the created field information item, the counterfield being at least one of an electric counterfield or a magnetic counterfield, wherein the counterfield is generated such that the counterfield least partially suppresses the emitted field.
System and Method for Testing Spatial Distribution Uniformity of Alkali Metal Atom Number Density of Atom Magnetometer
The present disclosure discloses a system and method for testing the spatial distribution uniformity of an alkali metal atom number density of an atom magnetometer. The system includes a detection laser, a laser beam expanding system, a polarizing element, a magnetic shielding system, an alkali metal atom gas chamber, a beam profile camera, a beam splitting prism, etc., which are sequentially arranged in a light advancing direction. In the method, based on an optical absorption principle, light intensity attenuations of linearly polarized light before and after passing through the alkali metal gas chamber are tested by using the beam profile camera with pixels in the level of um, a two-dimensional distribution matrix of an atom number density in space is calculated, and the distribution uniformity of the atom number density is analyzed by using a discrete coefficient.
Magnetic field measurement systems and methods employing feedback loops with a loops with a low pass filter
A magnetic field measurement system includes at least one magnetometer having a vapor cell, a light source to direct light through the vapor cell, and a detector to receive light directed through the vapor cell; at least one magnetic field generator disposed adjacent the vapor cell; and a feedback circuit coupled to the at least one magnetic field generator and the detector of the at least one magnetometer. The feedback circuit includes a first feedback loop that includes a first low pass filter with a first cutoff frequency and a second feedback loop that includes a second low pass filter with a second cutoff frequency. The first and second feedback loops are configured to compensate for magnetic field variations having a frequency lower than the first or second cutoff frequency, respectively.
Magnetic field measurement systems and methods employing feedback loops with a loops with a low pass filter
A magnetic field measurement system includes at least one magnetometer having a vapor cell, a light source to direct light through the vapor cell, and a detector to receive light directed through the vapor cell; at least one magnetic field generator disposed adjacent the vapor cell; and a feedback circuit coupled to the at least one magnetic field generator and the detector of the at least one magnetometer. The feedback circuit includes a first feedback loop that includes a first low pass filter with a first cutoff frequency and a second feedback loop that includes a second low pass filter with a second cutoff frequency. The first and second feedback loops are configured to compensate for magnetic field variations having a frequency lower than the first or second cutoff frequency, respectively.
METHOD AND APPARATUS FOR REDUCING MAGNETIC TRACKING ERROR DUE TO FLOOR DISTORTION
A method and apparatus for reducing magnetic tracking error in the position and orientation determined in a magnetic tracking system having a magnetic field generator. In some embodiments, the measured position and orientation of a sensor is compared to an expected theoretical position and orientation. Any error is assumed to be from “floor distortion,” i.e., eddy currents in the floor caused by the magnetic field generated by the magnetic field transmitter. The floor distortion is modeled as being caused by eddy currents caused by a second magnetic field transmitter that is a reflection of the actual transmitter. An algorithm iteratively searches over a parameter space to minimize the difference between the measured position and orientation and the theoretical position and orientation, and applies a correction to the measured position and orientation. The measurements and corrections of the position and orientation run in real-time with no additional hardware or calibration required.
METHOD AND APPARATUS FOR REDUCING MAGNETIC TRACKING ERROR DUE TO FLOOR DISTORTION
A method and apparatus for reducing magnetic tracking error in the position and orientation determined in a magnetic tracking system having a magnetic field generator. In some embodiments, the measured position and orientation of a sensor is compared to an expected theoretical position and orientation. Any error is assumed to be from “floor distortion,” i.e., eddy currents in the floor caused by the magnetic field generated by the magnetic field transmitter. The floor distortion is modeled as being caused by eddy currents caused by a second magnetic field transmitter that is a reflection of the actual transmitter. An algorithm iteratively searches over a parameter space to minimize the difference between the measured position and orientation and the theoretical position and orientation, and applies a correction to the measured position and orientation. The measurements and corrections of the position and orientation run in real-time with no additional hardware or calibration required.
MAGNETIC FIELD SENSOR, METHOD FOR PRODUCING SAME, AND METHOD FOR MEASURING A MAGNETIC FIELD
The present disclosure relates to a magnetic field sensor, in particular an angle sensor, including a magnetoresistive sensor component and a spin-orbit torque, SOT, sensor component.
MAGNETIC FIELD SENSOR, METHOD FOR PRODUCING SAME, AND METHOD FOR MEASURING A MAGNETIC FIELD
The present disclosure relates to a magnetic field sensor, in particular an angle sensor, including a magnetoresistive sensor component and a spin-orbit torque, SOT, sensor component.
MAGNETIC DETECTION DEVICE AND SEMICONDUCTOR INTEGRATED CIRCUIT FOR AMPLIFYING MAGNETIC DETECTION SIGNAL
A magnetic detection device that comprises an amplification circuit amplifying a detection signal from a magnetic sensor that is positioned, for example, in a location where an alternating current magnetic field enters as noise, and detects an alternating current magnetic field targeted for monitoring, said magnetic detection device further comprising: timer circuits that are activated in response to a change in the output of the amplification circuit, and if these clock a prescribed time, the outputs thereof change; a logic circuit that treats the outputs of the timer circuits as inputs; and an oscillation circuit for generating an operation clock signal for the timer circuits. The timer circuits are structured such that if the output of the amplification circuit changes to a different direction before the clocking of the prescribed time is complete, the timer circuits are reset.
MAGNETIC DETECTION DEVICE AND SEMICONDUCTOR INTEGRATED CIRCUIT FOR AMPLIFYING MAGNETIC DETECTION SIGNAL
A magnetic detection device that comprises an amplification circuit amplifying a detection signal from a magnetic sensor that is positioned, for example, in a location where an alternating current magnetic field enters as noise, and detects an alternating current magnetic field targeted for monitoring, said magnetic detection device further comprising: timer circuits that are activated in response to a change in the output of the amplification circuit, and if these clock a prescribed time, the outputs thereof change; a logic circuit that treats the outputs of the timer circuits as inputs; and an oscillation circuit for generating an operation clock signal for the timer circuits. The timer circuits are structured such that if the output of the amplification circuit changes to a different direction before the clocking of the prescribed time is complete, the timer circuits are reset.