Abstract: An angle sensor includes first and second detection units and an angle detection unit. Each of the first and second detection units generates two detection signals. The first and second detection units are arranged in a positional relationship that establishes predetermined phase relationships among the detection signals they generate. The angle detection unit includes first and second computing circuits and an angle computing unit. The first and second computing circuits generate first and second signals in each of which an error component corresponding to a fifth harmonic contained in the detection signals is reduced. The angle computing unit calculates a detected angle value on the basis of the first and second signals. The angle computing unit performs correction processing for reducing an error occurring in the detected angle value due to an error component corresponding to a third harmonic contained in the detection signals.

Abstract: An angle sensor includes a plurality of composite magnetic field information generation units and an angle computing unit. The plurality of composite magnetic field information generation units detect, at a plurality of detection positions, a composite magnetic field of a magnetic field to be detected and a noise magnetic field other than the magnetic field to be detected, and thereby generate a plurality of pieces of composite magnetic field information including information on the direction of the composite magnetic field. The angle computing unit generates a detected angle value by performing an operation using the plurality of pieces of composite magnetic field information so that an error of the detected angle value caused by the noise magnetic field is made smaller than in the case where the detected angle value is generated on the basis of any and only one of the plurality of pieces of composite magnetic field information.

Abstract: An angle sensor includes a detection signal generation unit for generating detection signals, an angle detection unit for generating a detected angle value on the basis of the detection signals, and a condition determination apparatus. The condition determination apparatus includes a determination value generation unit for generating a determination value to be used for determining the condition of the angle sensor, and a determination unit for determining the condition of the angle sensor. The angle detection unit includes a common correction processing unit for performing common correction processing for converting uncorrected signals, which have correspondence with the detection signals, into common corrected signals to be used for the generation of the detected angle value and the generation of the determination value. The common correction processing reduces an angular error occurring in the detected angle value, and narrows the variation range of the determination value.

Abstract: This sensor unit includes a base having a substantially-rectangular planar shape including a first side and a second side that are substantially orthogonal to each other, and a plurality of first sensors provided on the base and arranged on a first axis. The first axis is substantially parallel to the first side and passes through a center position of the base.

Abstract: An angle sensor includes a first to a fourth detection unit and an angle detection unit. Each of the first to the fourth detection unit generates two detection signals. The first to the fourth detection unit are arranged in a positional relationship that establishes predetermined phase relationships among the detection signals they generate. The angle detection unit performs operations using the detection signals to generate a first and a second signal in which an error component corresponding to a fifth or higher-order harmonic and an error component corresponding to a harmonic of the order other than the fifth order are lower than those in the detection signals. The angle detection unit then calculates a detected angle value on the basis of the first and the second signal.

Abstract: An angle sensor includes a detection signal generation unit for generating a plurality of detection signals, an angle detection unit for generating a detected angle value by performing an operation using the plural of detection signals, and a condition determination apparatus. The condition determination apparatus includes a determination value generation unit and a determination unit. The determination value generation unit performs an operation using the plurality of detection signals to generate a determination value corresponding to the condition of the angle sensor. The determination value varies depending on an angle to be detected. The determination unit determines whether the angle sensor is in a predetermined condition by determining whether the determination value falls within a determination range. The determination unit varies at least one threshold value that represents at least one end of the determination range.

Abstract: An angle sensor includes a detection signal generation unit for generating detection signals, and an angle detection unit for generating a detected angle value on the basis of the detection signals. The angle detection unit includes a signal conversion unit for performing a conversion operation, and an angle operation unit for performing an angle operation. The conversion operation is to convert the detection signals into first and second operation signals. The angle operation is to calculate the detected angle value using the first and second operation signals. The conversion operation includes an operation using a correction-term-containing function Which contains a correction term for reducing a first error or a second error occurring in the detected angle value. When the angle to be detected varies with a predetermined period, the first error varies with the predetermined period, whereas the second error varies with a period ½ the predetermined period.

Abstract: An angle sensor includes a detection signal generation unit, an angle detection unit for generating a detected angle value by performing an operation using detection signals, and a condition determination apparatus. The condition determination apparatus includes an initial determination value generation unit, correction processing unit and determination unit. The initial determination value generation unit performs an operation using the detection signals to generate an initial determination value corresponding to the angle sensor condition. The correction processing unit performs correction processing on the initial determination value to generate a corrected determination value. The determination unit determines whether the angle sensor is in a normal condition on the corrected determination value basis. The initial determination value contains a variation component which varies depending on an angle to be detected.

Abstract: A correction apparatus for an angle sensor includes a correction unit for performing first correction processing on a first detection signal and performing second correction processing on a second detection signal. The first correction processing is processing for combining the first detection signal and a first correction value to generate a first corrected detection signal. The second correction processing is processing for combining the second detection signal and a second correction value to generate a second corrected detection signal. The first correction value has a first amplitude and varies with a first period. The second correction value has a second amplitude and varies with a second period. The first and second amplitudes are of the same value. The first and second periods are of the same value equal to ? or ? of the period of an ideal component of each of the first and second detection signals.

Abstract: A rotational angle detection apparatus is provoded with a magnet disposed so as to be rotatable integrally with an axis of rotation, having a substantially circular shape when viewed along the axis of rotation, and including a magnetization vector component in a direction orthogonal to the axis of rotation; a magnetic sensor that outputs a sensor signal on the basis of change in a magnetic field accompanying rotation of the magnet; and a rotational angle detector that detects a rotational angle of the rotating body on the basis of the sensor signal output by the magnetic sensor; wherein the magnet has a curved inclined surface with a concave shape along the axis of rotation from a prescribed position on the outer side in a radial direction toward the axis of rotation, and when a circular virtual plane orthogonal to the axis of rotation and centered at the axis of rotation is established at a position opposed to the curved inclined surface, the magnetic sensor is disposed at a position at which the amplitudes

Abstract: A rotation angle sensing device is provided with a magnet that is placed to be integrally rotatable with a rotary shaft of a rotating body in association with a rotating body, where the shape of the magnet as viewed along the rotary shaft is substantially circular; a magnetic sensor part that outputs a sensor signal based upon a change in a direction of a magnetic field in association with the rotation of the magnet; and a rotation angle detecting part that detects a rotation angle of the rotating body based upon the sensor signal output by the magnetic sensor part. The magnet has a component of a magnetization vector in a direction that is orthogonal to the rotary shaft.

Abstract: A displacement detection unit includes a magnet and a magnetic detector. The magnet includes a first magnetic-pole region polarized into a south pole and a second magnetic-pole region polarized into a north pole, and generates a magnetic field around the magnet. The magnetic detector is movable relative to the magnet in a first direction, and detects a change in the magnetic field and thereby detects a displacement of the magnet in the first direction. The magnet includes a transition section in which a ratio of a magnetic volume of the second magnetic-pole region in a second direction to a magnetic volume of the first magnetic-pole region in the second direction gradually varies in the first direction. The second direction is orthogonal to the first direction.

Abstract: A displacement detection unit includes first and second sensors, an object, and a calculation section. The object includes first and second regions disposed periodically in a first direction, and performs displacement relative to the first and second sensors in the first direction. The first and second sensors detect first and second magnetic field changes in accordance with the displacement of the object and output the detected first and second magnetic field change as first and second signals, respectively. The first and second signals have different phases. The calculation section performs a calculation of an amount of the displacement of the object in the first direction multiple times per one period corresponding to a time period in which the object performs the displacement by an amount of displacement equivalent to a total of a continuous pair of the first and second regions, on a basis of the first and second signals.

Abstract: A rotating field sensor includes four detection circuits each of which generates an output signal responsive to the direction of a rotating magnetic field, and an angle calculation unit configured to calculate four angle values in correspondence to four groups each consisting of two detection circuits selected from the four detection circuits. The angle calculation unit calculates each of the four angle values on the basis of two output signals of the two detection circuits constituting a corresponding one of the four groups.

Abstract: A rotary sensing device that can accurately detect a rotation direction, even if a rotating body rotates at a high speed, when a gap between a plurality of subjects for detection in a rotating body varies is equipped with first to Nth sensor elements that are aligned to oppose the rotating body, which is rotatable in a rotation direction that can be either a normal rotation direction or a reverse rotation direction, and in parallel in respective order along the rotation direction, and that output first to Nth (N?3) sensor signals based upon the rotation of the rotating body, respectively, and a rotation direction detecting part that detects the rotation direction of the rotating body based upon each sensor signal output from each sensor element, and the rotation direction detecting part detects the rotation direction of the rotating body from a first differential signal that is obtained from the first sensor signal and the Mth (3?M?N) sensor signal, and a second differential signal obtained from the first sen

Abstract: A correction apparatus for an angle sensor includes a correction information generator for generating correction information, and a correction processing unit for performing correction processing in the course of generation of a detected angle value by an angle detector. Details of the correction processing are determined on the basis of the correction information. The correction information generator includes an error estimate generation unit and a correction information determination unit. The error estimate generation unit generates, on the basis of a first signal and a second signal, an error estimate containing a variable component that varies depending on an ideal angle estimate. The correction information determination unit determines the correction information on the basis of the error estimate.

Abstract: A magnetic sensor for detecting a component of an external magnetic field in a specific direction includes a resistor array including a plurality of resistive element sections each having a magnetoresistance element. Each of the plurality of resistive element sections has a different output characteristic curve with respect to the component of the external magnetic field in the specific direction.

Abstract: A first, a second, and a third computing circuit respectively generate a first post-computation signal with a second harmonic component reduced as compared with first and second signals, a second post-computation signal with the second harmonic component reduced as compared with third and fourth signals, and a third post-computation signal with the second harmonic component reduced as compared with fifth and sixth signals. A fourth and a fifth computing circuit respectively generate a fourth post-computation signal with a third harmonic component reduced as compared with the first and second post-computation signals, and a fifth post-computation signal with the third harmonic component reduced as compared with the second and third post-computation signals. A sixth computing circuit determines a detected angle value based on the fourth and fifth post-computation signals.

Abstract: A magnetic sensor system includes a scale and a magnetic sensor arranged in a relative positional relationship variable in a first direction, and a computing unit. The magnetic sensor includes a first detection circuit, a second detection circuit and a third detection circuit that are disposed at a first position, a second position and a third position, respectively. Each of the first to third detection circuits includes a spin-valve MR element. A difference between two of the first to third positions that are the most distant from each other in a first direction falls within a one-pitch amount of change in the relative positional relationship between the scale and the magnetic sensor. The computing unit generates first and second post-computation signals having mutually different phases by computation using detection signals from the first to third detection circuits.

Abstract: A magnetic sensor system includes a magnetic field generation unit for generating a target magnetic field and a magnetic sensor for detecting the target magnetic field, and is selectable between an operating state and a non-operating state. The magnetic sensor has a magnetic detection element including a magnetic layer whose magnetization direction varies according to the direction of the target magnetic field in a reference position. When in the operating state, the direction of the target magnetic field in the reference position varies when viewed from the magnetic sensor. When in the non-operating state, the direction of the target magnetic field in the reference position does not vary when viewed from the magnetic sensor and the magnetization direction of the magnetic layer is pinned in a first direction. The magnetic layer has an induced magnetic anisotropy that is imparted in advance to the magnetic layer.