Abstract: A rotating field sensor includes a first detection circuit that outputs a first signal indicating the intensity of a component of a rotating magnetic field in a first direction, a second detection circuit that outputs a second signal indicating the intensity of a component of the rotating magnetic field in a second direction, and an arithmetic circuit that calculates a detected angle value based on the first and second signals. Each of the first and second detection circuits includes at least one MR element row. Each MR element row is composed of a plurality of MR elements connected in series. Each MR element has a magnetization pinned layer. The plurality of MR elements forming each MR element row include one or more pairs of MR elements. Magnetization directions of the magnetization pinned layers in two MR elements making up a pair form a predetermined relative angle other than 0° and 180°.

Abstract: An angle detection unit including first to third arithmetic units receives first and second signals that are associated with intensities of components of a rotating magnetic field in mutually different directions. The first arithmetic unit generates a sum of squares signal made up of the sum of squares of the first and second signals. Based on the sum of squares signal, the second arithmetic unit calculates a first error component estimate which is an estimated value of a first error component included in the first signal and a second error component estimate which is an estimated value of a second error component included in the second signal. The third arithmetic unit generates a first corrected signal by subtracting the first error component estimate from the first signal, generates a second corrected signal by subtracting the second error component estimate from the second signal, and calculates a detected angle value based on the first and second corrected signals.

Abstract: A first detection unit has first and second detection circuits. A second detection unit has third and fourth detection circuits. Output signals of the second and fourth detection circuits differ from output signals of the first and third detection circuits in phase, respectively, by an odd number of times ¼ the signal period. The output signal of the third detection circuit differs from the output signal of the first detection circuit in phase by an integer multiple of ? the signal period other than an integer multiple of ½ the signal period. A rotating field sensor generates a first signal based on the output signals of the first and third detection circuits, generates a second signal based on the output signals of the second and fourth detection circuits, and calculates a detected angle value based on the first and second signals.

Abstract: A field generation unit generates a rotating magnetic field including a first partial magnetic field in a first position and a second partial magnetic field in a second position. The first and second partial magnetic fields differ in direction by 180° and rotate in the same direction of rotation. A first detection unit detects, in the first position, a first angle that the direction of a first applied field forms with respect to a first direction. The first applied field includes the first partial magnetic field as its main component. A second detection unit detects, in the second position, a second angle that the direction of a second applied field forms with respect to a second direction. The second applied field includes the second partial magnetic field as its main component. A detected value of the angle that the direction of the rotating magnetic field in a reference position forms with respect to a reference direction is calculated based on detected values of the first and second angles.

Abstract: A field generation unit generates a rotating magnetic field including a first partial magnetic field in a first position and a second partial magnetic field in a second position. The first and second partial magnetic fields differ in direction by 180° and rotate in the same direction of rotation. A first detection unit located in the first position has first and second detection circuits whose output signals differ in phase by ¼ the period. A second detection unit located in the second position has third and fourth detection circuits whose output signals differ in phase by ¼ the period. A detected value of the angle that the direction of the rotating magnetic field in a reference position forms with respect to a reference direction is calculated based on a first signal generated from the output signals of the first and third detection circuits and a second signal generated from the output signals of the second and fourth detection circuits.

Abstract: While an emitting position of light from an optical waveguide and a magnetic pole end part are made closer to each other, high-density writing onto a magnetic recording medium is realized. A thermally assisted magnetic head comprises a main magnetic pole layer having a magnetic pole end part exposed at a medium-opposing surface opposing a magnetic disk, and an optical waveguide for deflecting laser light incident thereon into a laminating direction. The main magnetic pole layer is positioned on a side where the light is deflected by the optical waveguide. The magnetic pole end part projects to the side where the light is deflected by the optical waveguide. The optical waveguide projects more than the magnetic pole end part on the medium-opposing surface side.

Abstract: A magnetic sensor includes a spin valve-type magneto-resistive element, a voltage detection part, a coil, and a current control part, the coil being configured to apply a measuring magnetic field to the spin valve-type magneto-resistive element upon application of a current, the voltage detection part being configured to output a detection signal to the current control part upon detecting an output voltage of the spin valve-type magneto-resistive element reaching a predetermined voltage value, the current control part being configured to control the current to unidirectionally increase or unidirectionally decrease a strength of the measuring magnetic field from an initial value, but upon input of the detection signal, control the current to return the strength of the measuring magnetic field to the initial value, the initial value being a magnetic field strength where the spin valve-type magneto-resistive element reaches saturation magnetization.

Abstract: A method of forming a thin-film magnetic head comprises a lower magnetic pole layer forming step of forming a lower magnetic pole layer; a lower magnetic pole projection forming step of forming the lower magnetic pole layer with a lower magnetic pole projection; a gap layer forming step of laminating a nonmagnetic gap layer on the lower magnetic pole projection; and an upper magnetic pole forming step of forming an upper magnetic pole on the nonmagnetic gap layer. The lower magnetic pole projection forming step forms the lower magnetic pole projection by simultaneously etching an area including parts adjacent to a part to become the lower magnetic pole projection on both sides in a track width direction and a part adjacent to the part to become the lower magnetic pole projection on the side opposite from a medium-opposing surface in a surface of the lower magnetic pole layer.

Abstract: The present invention provides a thin-film magnetic head which surely improves the writing and reading characteristic with reducing the flying height and surely handles the contact or collision with the magnetic recording medium. A thin-film magnetic head is provided, which includes, an substrate with ABS; a read or write head element provided on an element-formed surface of the substrate; at least one protrusion adjustment portion whose end reaches a slider end surface on the ABS side, which provides on an element-formed surface of the substrate; at least one heating portion provided rear at least one protrusion adjustment portion viewed from the slider end surface on the ABS side.

Abstract: Provided is a thin-film magnetic having improved write characteristics in the high-frequency band. The head comprises an electromagnetic coil element comprising upper and lower magnetic layers, a write gap layer and a write coil layer, and in the electromagnetic coil element, at least one non-magnetic layer is provided within the upper magnetic layer, and further, an upper surface, a lower surface, at least a portion of a front surface and at least a portion of a rear surface of the non-magnetic layer are covered with magnetic material of at least one of the upper magnetic layer and the lower magnetic layer.

Abstract: A multi-channel head includes a substrate, a plurality of write elements arranged in a track width direction above the substrate in a lamination direction, and a plurality of read elements arranged in the track width direction above the plurality of write elements in the lamination direction. At least one of the plurality of write elements is offset from the others in the lamination direction. All the plurality of read elements are located higher than an uppermost one of the plurality of write elements in the lamination direction.

Abstract: A thin-film magnetic head which suppresses the TPTP phenomenon due to the environment temperature is provided. The thin-film magnetic head includes, an electromagnetic coil element having a coil layer and coil-insulating layer, and an overcoat layer. A width of the coil-insulating layer in a track-width direction is larger than a width that is needed to insulate the whole coil layer, and is at least 46 ?m, and a length of the coil-insulating layer in a direction perpendicular to the track-width direction is larger than a length that is needed to insulate the whole coil layer, and is at least 75 ?m. In addition, a heat expansion coefficient of the coil-insulating layer is larger than or equal to 30×10?6/K, and a Young's modulus of the coil-insulating layer is larger than or equal to 1 GPa and smaller than or equal to 4 GPa.

Abstract: A magnetic sensor includes a first detection unit and a second detection unit. The first detection unit calculates a first detection angle which is a detected value of a first angle that a direction of an external magnetic field in a first position forms with respect to a first direction. The second detection unit calculates a second detection angle which is a detected value of a second angle that the direction of the external magnetic field in a second position forms with respect to a second direction. The first detection angle includes a first angular error. The second detection angle includes a second angular error. The first angular error and the second angular error differ in phase by an odd number of times ½ of the error period.

Abstract: A magnetic sensor for detecting a direction of an external magnetic field comprises: a bridge circuit configured to provide an output that changes in accordance with the direction of the external magnetic field, the bridge circuit including four resistance element sections, each of which comprises at least one magnetoresistance effect element; and two resistors connected to respective output terminals of the bridge circuit. The ratio of the resistance of each of the resistors to that of the bridge circuit is at least 2 when the resistance of each of the resistance element sections is at a minimum corresponding to a change in magnetoresistance.

Abstract: The angle-of-rotation sensor apparatus of the invention comprises a shaft supported rotatably about an axial center, a permanent magnet fixed to one end face of the shaft, and a magnetic field sensor device located in opposition to the permanent magnet at a constant spacing. The permanent magnet used is in a cuboidal shape and magnetized in the minor axis (X) direction at the rectangular surface opposing to the magnetic field sensor device. The minor axis side is defined as the X direction and the major axis side as the Y direction. Given the opposing surface of the same area, the area where the angle distribution of the magnetic field emitted out of the permanent magnet can be placed in a uniform direction is made so wide that the tolerance range for axial alignment errors between the magnetic field sensor device and the permanent magnet can be enlarged.

Abstract: A magnetic sensor includes first to fourth MR elements. The first and second MR elements are connected at respective ends thereof through a first connecting portion in a central region. The third and fourth MR elements are connected at respective ends thereof through a second connecting portion that crosses the first connecting portion with a distance in a thickness direction in the central region. The first and fourth MR elements are connected at respective other ends thereof through a third connecting portion, and the second and third MR elements are connected at respective other ends thereof through a fourth connecting portion. Resistance values of the first and third MR elements change in a same increasing/decreasing direction, whereas resistance values of the second and fourth MR elements change in an increasing/decreasing direction opposite to the first and third MR elements, depending on an external signal magnetic field.

Abstract: A magnetoresistive element includes magnetoresistive films each having an upper surface and a lower surface, and conductors combining the magnetoresistive films in series and including top electrodes and bottom electrodes. Each one of the top electrodes and corresponding one of the bottom electrodes oppose each other to sandwich corresponding one of the magnetoresistive films. Each electrode of the top electrodes and the bottom electrodes includes a stem section and a branch section, the stem section extending in a direction along a series alignment direction of the magnetoresistive films, and the branch section extending along the lamination plane in a direction intersecting a direction in which the stem section extends. The branch section in the top electrode is in contact with an upper surface of the corresponding magnetoresistive film, and the branch section in the bottom electrode is in contact with a lower surface of the corresponding magnetoresistive film.

Abstract: A magnetic sensor includes a bridge circuit with a first, a second, a third, and a fourth resistor annularly and electrically connected together in this order, and a compensation resistor. The compensation resistor is connected to a first point between the fourth resistor and the first resistor. The first to fourth resistors include a first to fourth tunnel magneto-resistance element, respectively. Each of the magnetization directions in the magnetization fixed layers in the second and fourth magneto resistance elements is opposite to the magnetization direction in the magnetization fixed layer in the first magneto resistance element. The magnetization direction in the magnetization fixed layer in the third magneto resistance element is the same as the magnetization direction in the magnetization fixed layer in the first magneto resistance element. The resistance of the compensation resistor varies with a period of 180 degrees with respect to a rotation angle of the external field.

Abstract: A magneto-resistance effect element for a sensor to sense a variation in externally applied magnetism includes a pinned layer having a fixed magnetization direction, a free layer having a magnetization direction which varies in response to an external magnetic field, and an intermediate layer provided between the pinned layer and the free layer. The pinned layer has a planar shape which is long in the fixed magnetization direction and which is short in a direction orthogonal to the fixed magnetization direction. Moreover, the pinned layer preferably has a planar shape in which the pinned layer is divided into a plurality of sections.

Abstract: A substructure in which a plurality of pre-head portions are aligned in rows is to be cut later so that the pre-head portions are separated from one another. A surface formed by cutting the substructure is lapped to form medium facing surfaces. The substructure includes a plurality of sensors that respectively show individual sensor values corresponding to values of a plurality of different parameters each of which has an influence on characteristics relating to the pole layer and each of which depends on the position of the medium facing surface. The individual sensor values are resistance values each of which varies according to the position of the medium facing surface. The plurality of sensors are electrically connected to each other to form a composite sensor that shows a composite sensor value, which is a resistance value that depends on the resistance values of the plurality of sensors.