A rotation detection device includes: a detector arranged with a gap to a rotating body in which rotation position information is periodically provided at regular intervals, and detecting a magnetic change as a rotation position of the rotating body; and a signal processor acquiring the rotation position information. The detector has first and second magnetic elements arranged with an interval of a/2 in a rotation direction. Each regular interval is defined as a. The first magnetic element outputs a first signal having a period corresponding to the regular intervals. The second magnetic element outputs a second signal having an opposite phase to the first signal and the period. The signal processor acquires a differential signal between the first and second signals as the rotation position information.

A position-measuring device includes a carrier body and scanning units movable relative thereto. At least three surfaces of the carrier body each carry a first and second measuring graduation, each having a series of graduation lines. Each of the measuring graduations is associated with a scanning unit for scanning the respective measuring graduation at a scanning location such that, for each surface, two scanning units are disposed for scanning the respective measuring graduations. In each case, these two scanning units are disposed in such a way, and the graduation lines of the two measuring graduations are inclined with respect to each other in such a way, that two normal planes extending respectively in the direction of the respective graduation lines through the respective scanning locations of the two scanning units have a common axis of intersection, whereby the three resulting axes of intersection extend through a common point.

A scale includes a base material, scale patterns arranged at a predetermined periodicity on a main surface of the base material, and a fluorine film that covers the scale patterns and is at least partly a monomolecular fluorine compound.

An optical encoder includes an encoding disk and an optical detector disposed to correspond to the encoding disk. The optical detector includes a plurality of optical sensors arranged to form an optical sensor array. The optical detector is provided to receive light. The optical detector includes at least one optical sensor arranged to form at least one sensor array. The width of the sensor array corresponds to an interpolation period of the optical encoder.

An optical encoder includes an encoding disk and an optical detector disposed to correspond to the encoding disk. The optical detector includes a plurality of optical sensors arranged to form an optical sensor array. The optical detector is provided to receive light. The optical detector includes at least one optical sensor arranged to form at least one sensor array. The width of the sensor array corresponds to an interpolation period of the optical encoder.

An embodiment of the present invention relates to a rotor position detecting apparatus and a motor and a motor-driven steering apparatus comprising same, the rotor position detecting apparatus comprising: a substrate, a magnetic Hall-signal element mounted on the substrate, and a first ground pattern disposed on one side of the substrate and electrically connected to the magnetic Hall-signal element. As a result, the motor can reduce probability of faults due to electromagnetic waves or static electricity.

A magnetic sensor system may include a first magnetic sensor and a second magnetic sensor. The first magnetic sensor may include a first triplet of sensor elements for measuring a magnetic field. The first triplet of sensor elements may be aligned linearly along a direction of movement. A first pair of differential signals, output by the first magnetic sensor, may indicate a position of the magnetic sensor system, along the direction of movement, relative to a magnetic pole pair. The second magnetic sensor may include a second triplet of sensor elements for measuring the magnetic field. The second triplet of sensor elements may be aligned linearly along the direction of movement. The second magnetic sensor may be positioned relative to the first magnetic sensor such that a second pair of differential signals, output by the second magnetic sensor, indicates a position of the magnetic sensor system across multiple pole pairs.

The linear conveyor device includes a position detecting device including a scale attached to a slider, and a sensor structural body including a sensor and a driver. The driver is provided with a first and a second signal processing units, and a signal comparison processing unit. The first signal processing unit performs predetermined first interpolation processing on an output signal from a first sensor, generates and outputs first positional data. The second signal processing unit performs predetermined second interpolation processing on an output signal from a second sensor, generates second positional data, and outputs the second positional data. The signal comparison processing unit recognizes the first positional data as positional information of the slider, generates identification information unique to the slider, and outputs the identification information, where the identification information corresponds to a difference between the first positional data and the second positional data.

A sensor system comprises a magnetic field generator and a sensor device arranged at a distance from said magnetic field generator and adapted for measuring or determining at least one magnetic field component and/or at least one magnetic field gradient component. The magnetic field generator comprises a multi-pole magnet having a number N of pole pairs that are axially magnetized to generate an N-pole magnetic field that is substantially rotationally symmetric around an axis. The magnet comprises a plurality of grooves and/or elongate protrusions that are arranged in a rotationally symmetric pattern around the axis to provide a substantially constant magnetic field gradient in a central region around said axis.

A linear or angular position sensor system comprising a magnetic structure for generating a magnetic field, and a sensor device movable relative to the magnetic structure. The sensor device comprises a plurality of sensor elements for measuring at least two characteristics of said magnetic field, and a processing circuit for determining a linear or angular position of the sensor device relative to the magnetic structure in accordance with a predefined function of these characteristics (e.g. components or gradients). The magnetic structure comprises one or more grooves, having a shape and size which can be described by a limited set of parameters, having values optimized to reduce a maximum error between the actual position of the sensor device, and the calculated position based on said predefined function, by at least a factor of 2.