In one aspect the invention provides a magnetic door position detection apparatus adapted to attach to a cabinet interior with a door arranged to transition between an open state where the interior of the cabinet is accessible, and a closed state. The door includes a magnetic field generating structure configured to magnetically engage the door with the cabinet in the closed state. The apparatus provided includes a housing configured to attach to the interior of the cabinet and one or more sensors configured to determine change in the magnetic flux field within the interior of the cabinet induced by motion of the magnetic field generating structure in at least one of three orthogonal axes. The sensor or sensors generate an output signal representing the sensed magnetic field change where the one or more axes is indicative of the cabinet door moved between the closed state and the open state.

A position sensor system includes a magnetic source for generating a magnetic field, and a position sensor device movable relative to the magnetic source, or vice versa. The position sensor device comprises at least three magnetic sensor elements for measuring at least three magnetic field values of the magnetic field, and a processing circuit configured for determining at least two magnetic field gradients or magnetic field differences based on the at least three magnetic field values, and for deriving from the at least two magnetic field gradients or differences a first value indicative of a position of the position sensor device, and for deriving from the at least two magnetic field gradients or differences a second value indicative of integrity of the position sensor system.

A position sensor system includes a magnetic source for generating a magnetic field, and a position sensor device movable relative to the magnetic source, or vice versa. The position sensor device comprises at least three magnetic sensor elements for measuring at least three magnetic field values of the magnetic field, and a processing circuit configured for determining at least two magnetic field gradients or magnetic field differences based on the at least three magnetic field values, and for deriving from the at least two magnetic field gradients or differences a first value indicative of a position of the position sensor device, and for deriving from the at least two magnetic field gradients or differences a second value indicative of integrity of the position sensor system.

A magnet arrangement for generating a selection magnetic field with a gradient and a field-free region in a sample volume includes: a Maxwell magnet system with two ring magnets, which are arranged in coaxial fashion and at a distance from one another on a common Z-axis extending through the sample volume, a focus field coil arrangement with at least one focus field coil pair for displacing the field-free region within the sample volume, and a drive coil for generating an MPI drive field. The magnet arrangement comprises a quadrupole magnet system with at least one quadrupole ring for generating a quadrupole magnetic field, the quadrupole magnet system being arranged coaxially with respect to the Maxwell magnet system. Using the magnet arrangement according to the invention, it is possible to switch between a selection magnet field with a field-free point and a field-free line without undesirably increasing the field gradient.

In a magnetic sensor using a magnetic impedance effect, sensitivity is improved as compared to the case where a width of a sensitive element in the short direction is equal from one end to the other end in the longitudinal direction. The magnetic sensor includes: a non-magnetic substrate; and a sensitive element that is provided on the substrate, composed of a soft magnetic material, having a longitudinal direction and a short direction, provided with uniaxial magnetic anisotropy in a direction crossing the longitudinal direction, having a width at a center portion in the longitudinal direction that is smaller compared to a width at each of both end portions in the longitudinal direction, and sensing a magnetic field by a magnetic impedance effect.

A magnetic distribution detection method includes the steps of providing a magnetic sensor and a sample, selecting a multiple of measuring points on the sample, sensing the measuring points by the magnetic sensor, obtaining a multiple of sense data and a series of the heights of the magnetic sensor from each measuring point, using a signal decomposition algorithm to convert these sense data into data groups, and selecting one of the data groups as the magnetic distribution data of the sample.

In a current detection apparatus which detects current flowing through the armature windings of plural phases of plural sets using each magnetic sensor which is disposed at a position the magnetic flux radially emitted from the rotor crosses, to provide a current detection apparatus which can suppress that the control accuracy of output torque is deteriorated by the current detection error which occurs due to the magnetic flux of the rotor. A current detection apparatus, wherein in each set, the magnetic sensors of n-phase are disposed so that an absolute value of a detection component of a rotor flux density which is a component of flux density of the rotor detected by the magnetic sensor of each phase become equal with each other.

In a current detection apparatus which detects current flowing through the armature windings of plural phases of plural sets using each magnetic sensor which is disposed at a position the magnetic flux radially emitted from the rotor crosses, to provide a current detection apparatus which can suppress that the control accuracy of output torque is deteriorated by the current detection error which occurs due to the magnetic flux of the rotor. A current detection apparatus, wherein in each set, the magnetic sensors of n-phase are disposed so that an absolute value of a detection component of a rotor flux density which is a component of flux density of the rotor detected by the magnetic sensor of each phase become equal with each other.

A magnetic sensor module includes an axially polarized back bias magnet having a body that radially extends from an inner sidewall to an outer sidewall and a bore that defines the inner sidewall. The magnet generates a radially symmetric bias magnetic in-plane field about a center axis in a sensor plane. The magnetic field has a magnetic flux density of substantially zero along the extension of the center axis and at a circumference of a zero-field circle located in the sensor plane, where the circumference of the zero-field circle vertically overlaps with the magnet body in a plan view. The magnetic sensor module includes a magnetic sensor including at least three sensor elements arranged in the sensor plane at locations where the radially symmetric bias magnetic in-plane field has a magnetic flux density of substantially zero, including at least two sensor elements being arranged on the circumference of the zero-field circle.

A system and method of effectively measuring a change in a gradient of a magnetic field. The systems include a first magnet and a second magnet mechanically coupled together and aligned along a polarization axis. The first magnet and the second magnet are positioned such that a pair of like magnetic poles of the first magnet and the second magnet face in opposite directions. Further, the first magnet and the second magnet are configured to move along the polarization axis in response to a magnetic field. A sensing system is configured to measure a change in a gradient of the magnetic field based on the movement of the first magnet and second magnet along the polarization axis in response to the magnetic field.