Magnetic field components are measured at multiple longitudinal positions and used to calculate estimated longitudinal position and length of a transversely localized electric current segment flowing across a gap between conductive bodies. The apparatus can be used with a remelting furnace. The electrode and ingot act as the conductive bodies, and arcs, discharges, or slag currents are the current segments spanning the gap. Actuators for movable sensors can be coupled to the sensors in a servomechanism arrangement to move the sensors along with the moving gap. An actuator for moving one of the conductive bodies can be coupled to sensors in a servomechanism arrangement to maintain the gap distance within a selected range as the gap moves.

Magnetic field components are measured at multiple longitudinal positions and used to calculate estimated longitudinal position and length of a transversely localized electric current segment flowing across a gap between conductive bodies. The apparatus can be used with a remelting furnace. The electrode and ingot act as the conductive bodies, and arcs, discharges, or slag currents are the current segments spanning the gap. Actuators for movable sensors can be coupled to the sensors in a servomechanism arrangement to move the sensors along with the moving gap. An actuator for moving one of the conductive bodies can be coupled to sensors in a servomechanism arrangement to maintain the gap distance within a selected range as the gap moves.

The invention relates to a method for determining the component of a magnetic field in a predetermined direction. The method comprises preparing a quantum system in a coherent superposition state (S1), letting the quantum system evolve for a delay time period (S2) and performing a readout operation and a projective measurement on the quantum system (S3). The steps (S1, S2, S3) are iteratively repeated in an iteration loop, wherein the delay time period increases linearly by the same time increment after each iteration. The method further comprises determining the component of the magnetic field in the predetermined direction according to the outcome of the projective measurements (S4).

The invention relates to a method for determining the component of a magnetic field in a predetermined direction. The method comprises preparing a quantum system in a coherent superposition state (S1), letting the quantum system evolve for a delay time period (S2) and performing a readout operation and a projective measurement on the quantum system (S3). The steps (S1, S2, S3) are iteratively repeated in an iteration loop, wherein the delay time period increases linearly by the same time increment after each iteration. The method further comprises determining the component of the magnetic field in the predetermined direction according to the outcome of the projective measurements (S4).

Position sensors, including linear position sensors, that utilize magnetic field(s) are disclosed. Disclosed sensors include flux emitters and sensor assemblys. The sensor assemblys include flux collectors that interact with magnetic fields from flux emitters and with a magnetism sensing device. Flux emitters have arrangements of magnets that when combined with the sensor assembly can provide a constantly increasing or a constantly decreasing signal across a range of relative movement.

Position sensors, including linear position sensors, that utilize magnetic field(s) are disclosed. Disclosed sensors include flux emitters and sensor assemblys. The sensor assemblys include flux collectors that interact with magnetic fields from flux emitters and with a magnetism sensing device. Flux emitters have arrangements of magnets that when combined with the sensor assembly can provide a constantly increasing or a constantly decreasing signal across a range of relative movement.

A metal detection apparatus that can accurately and automatically determine whether a metal passing through the inspection area is a magnetic or non-magnetic metal comprises a detection unit quadrature-detecting a differential detection signal of magnetic field fluctuation in the inspection area due to the passage of a workpiece, and a determination unit that determines the presence or absence of a mixed metal based on both fluctuation components after the detection. The determination unit compares sample signal phase data obtained beforehand from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of various metal samples, with the signal phase data obtained from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of the workpiece mixed with metal, and determines the type of metal passing through the inspection area based on the phase determination result.

A metal detection apparatus that can accurately and automatically determine whether a metal passing through the inspection area is a magnetic or non-magnetic metal comprises a detection unit quadrature-detecting a differential detection signal of magnetic field fluctuation in the inspection area due to the passage of a workpiece, and a determination unit that determines the presence or absence of a mixed metal based on both fluctuation components after the detection. The determination unit compares sample signal phase data obtained beforehand from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of various metal samples, with the signal phase data obtained from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of the workpiece mixed with metal, and determines the type of metal passing through the inspection area based on the phase determination result.

A magnetic sensor includes a plurality of magnetoresistive element units. Each of the magnetoresistive element units includes a flat-surface-type first magnetoresistive element having a detection axis in a first direction and a flat-surface-type second magnetoresistive element having a detection axis in a second direction different from the first direction. The first magnetoresistive element and the second magnetoresistive element are arranged so as to face each other. The plurality of magnetoresistive element units are arrayed in a direction orthogonal to flat surfaces of the first magnetoresistive element and the second magnetoresistive element. The surfaces facing a measurement sample constitute a surface parallel to the direction in which the magnetoresistive element units are arrayed.

A magnetic sensor includes a plurality of magnetoresistive element units. Each of the magnetoresistive element units includes a flat-surface-type first magnetoresistive element having a detection axis in a first direction and a flat-surface-type second magnetoresistive element having a detection axis in a second direction different from the first direction. The first magnetoresistive element and the second magnetoresistive element are arranged so as to face each other. The plurality of magnetoresistive element units are arrayed in a direction orthogonal to flat surfaces of the first magnetoresistive element and the second magnetoresistive element. The surfaces facing a measurement sample constitute a surface parallel to the direction in which the magnetoresistive element units are arrayed.