An electromagnetic tracking system including a patient support element and an electromagnetic field generator. The patient support element is superposed relative to the electromagnetic field generator, and the electromagnetic field generator is selectively moveable relative to the patient support element.

A magnetometer includes an electron spin defect body including a plurality of lattice point defects. A microwave field transmitter is operable to apply a microwave field to the electron spin defect body. An optical source is configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect body from a ground state to an excited state. A first optical fiber has an input end optically coupled to the optical source and an output end. The output end is attached to a first face of the electron spin defect body and is arranged to direct the input light into the first face of the electron spin defect body. A second optical fiber has an output end and an input end. A photodetector is optically coupled to the output end of the second optical fiber.

A magnetometer includes an electron spin defect body including a plurality of lattice point defects. A microwave field transmitter is operable to apply a microwave field to the electron spin defect body. An optical source is configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect body from a ground state to an excited state. A first optical fiber has an input end optically coupled to the optical source and an output end. The output end is attached to a first face of the electron spin defect body and is arranged to direct the input light into the first face of the electron spin defect body. A second optical fiber has an output end and an input end. A photodetector is optically coupled to the output end of the second optical fiber.

A target value of magnetic flux density and magnetic flux density actually obtained are made to coincide precisely with each other. An electromagnet control device comprises a current value determining unit for determining, based on a magnetic flux density instruction value, a value of current that is made to flow through a coil. The current value determining unit is constructed to execute a second process for determining, based on a second function, a value of the current, if the magnetic flux density is to be decreased from that in a first magnetization state, and a fourth process for expanding or reducing the second function by use of a first scaling ratio for transforming it to a fourth function, and determining, based on the fourth function obtained after above transformation, a value of the current, if the magnetic flux density is to be decreased from that in a third magnetization state.

A method may include measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, correlating a relationship between the mechanical parameter and the electrical parameter, and calibrating the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

A method may include measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, correlating a relationship between the mechanical parameter and the electrical parameter, and calibrating the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

A magnetic response distribution visualization device includes: an induction circuit that induces a magnetic field component from outside a moving object; a sensor that senses a strength and a phase of the magnetic field at a plurality of points in times outside the moving object; and an information processing circuit that, based on a sensing result of the strength and the phase, a moving speed of the moving object, and a fundamental equation for magnetic fields, calculates a strength and a phase of the magnetic field at a vicinal position closer to the moving object than the sensor, and generates, based on a calculation result of the strength and the phase, a magnetic response distribution image for security inspection that shows a distribution of a response of the moving object to the magnetic field component induced by the induction circuit.

An apparatus and a method provide an output signal indicative of a speed of rotation and/or a direction of movement of a ferromagnetic object. The sensor includes at least one magnetic field sensing element configured to generate a magnetic field signal in response to a magnetic field associated with an object. The sensor includes a detector configured to generate a detector signal having edges occurring in response to a comparison of the magnetic field signal and the threshold signal. The sensor includes an output circuit configured to generate an output signal having a first format when a characteristic of the magnetic field signal is within a first range and having a second format different than the first format when the characteristic of the magnetic field signal is within a second range, different than the first range.

An apparatus and a method provide an output signal indicative of a speed of rotation and/or a direction of movement of a ferromagnetic object. The sensor includes at least one magnetic field sensing element configured to generate a magnetic field signal in response to a magnetic field associated with an object. The sensor includes a detector configured to generate a detector signal having edges occurring in response to a comparison of the magnetic field signal and the threshold signal. The sensor includes an output circuit configured to generate an output signal having a first format when a characteristic of the magnetic field signal is within a first range and having a second format different than the first format when the characteristic of the magnetic field signal is within a second range, different than the first range.

A micro-electro-mechanical system (MEMS) magnetometer is provided for measuring magnetic field components along three orthogonal axes. The MEMS magnetometer includes a top cap wafer, a bottom cap wafer and a MEMS wafer having opposed top and bottom sides bonded respectively to the top and bottom cap wafers. The MEMS wafer includes a frame structure and current-carrying first, second and third magnetic field transducers. The top cap, bottom cap and MEMS wafer are electrically conductive and stacked along the third axis. The top cap wafer, bottom cap wafer and frame structure together form one or more cavities enclosing the magnetic field transducers. The MEMS magnetometer further includes first, second and third electrode assemblies, the first and second electrode assemblies being formed in the top and/or bottom cap wafers. Each electrode assembly is configured to sense an output of a respective magnetic field transducer induced by a respective magnetic field component.