Abstract: An embodiment of a magnetic-field sensor has a plurality of sensor elements connected to form measurement arrangements, each measurement arrangement having a measurement tap, and a control circuit formed to perform an embodiment of a method of calibrating the magnetic-field sensor.

Abstract: A sensor arrangement for measuring current is disclosed. The sensor arrangement includes a substrate, at least one Hall element integrated in or arranged on the substrate, a first coil that is spaced apart from a surface of the substrate in a vertical direction, a second coil that is spaced apart in a vertical direction from the first coil, and an isolation layer that is arranged between the first coil and the second coil.

Abstract: A measuring bridge arrangement has a measuring bridge with a first supply terminal and first and second measuring signal terminals. The measuring bridge arrangement has a working point adjustment circuit formed to feed the measuring bridge via at least the first supply terminal in a measuring state of operation, and to apply a signal to one of the measuring signal terminals in the test state of operation in order to bring the measuring bridge to a test working point different from a measuring working point in the measuring state of operation. The measuring bridge has a test tap, wherein a test signal dependent on resistive properties of at least one element of the measuring bridge can be tapped at the test tap of the measuring bridge.

Abstract: An electromagnetic logging tool is disclosed that includes a support; and at least one four-coil array disposed on the support, wherein the at least one four-coil array comprises: a transmitter, a bucking coil, a receiver, and a trim coil. A method for balancing an induction array is disclosed that includes applying an alternating current to a transmitter of the induction array that comprises the transmitter, a bucking coil and a receiver; measuring a mutual coupling between the transmitter and the receiver; and adding an extra bucking coil, if the mutual coupling exceeds a selected criterion.

Abstract: The invention relates to a calibration standard, especially for the calibration of devices for the non-destructive measurement of the thickness of thin layers, with a carrier layer (12) consisting of a basic material and a standard (17) applied on the carrier layer (12), said standard having the thickness of the layer to be measured at which the device is to be calibrated, with the carrier layer (12) comprising a plane-parallel measuring surface (16) to its bearing surface (14), that the standard (17) comprises a bearing surface (18) plane-parallel with its measuring surface (19) for bearing on the measuring surface (16) of the carrier layer (12), and that the standard (17) is permanently provided on the carrier layer (12) by means of plating by rubbing.

Abstract: A method is provided for preserving the transverse biasing of a GMR (or MR) read head during back-end processing. In a first preferred embodiment, the method comprises magnetizing the longitudinal biasing layers of the read head in a transverse direction, so that the resulting field at the position of the transverse biasing layer places it in a minimum of potential energy which stabilizes its direction. The field of the longitudinal biasing layer is then reset to the longitudinal direction in a manner which maintains the transverse biasing direction. In a second embodiment, a novel fixture for mounting the read head during processing includes a magnetic portion which stabilizes the transverse bias of the read head. The two methods may be used singly or in combination.

Abstract: A method for generating, displaying and manipulating the orientation of three-dimensional vectors on a two-dimensional surface for visualization, statistical analysis and correlation. The method involves collecting vector data, transforming each vector into spherical co-ordinates, then assigning, a unique color related to a position on a spherical color model. A two-dimensional raster image filled with this unique color is centered at the point of measurement for each vector orientation as obtained from calculations or instrumentation capable of measuring this orientation. This methodology offers the user the ability to discriminate the location of specific orientations as well as the ability to define an enhanced full color gamut gradation for a specific range of orientation. This rendering of color-coded vector orientation enables easier understanding by the viewer of large data sets.

Abstract: A quasi-static tester is disclosed. The quasi static tester comprises: a mount configured to fix a head gimbal assembly in a given position; a camera configured to observe the head gimbal assembly when the head gimbal assembly is fixed in the mount, wherein the camera is used to position the head gimbal assembly in an observation position; and a magnet for performing quasi-static testing of the head gimbal assembly when the head gimbal assembly is fixed in the mount, wherein the observation position and a testing position in a uniform area of the magnet are a predetermined distance apart.

Abstract: The present invention provides a method to compensate for the sensitivity drift of a magnetic field sensor for sensing a magnetic field. The magnetic field sensor comprises at least four electrodes. The method comprises a first step where a first set of two electrodes is used to bias the sensor and a second set of two electrodes is used to sense an output signal of the magnetic field sensor, and a second step where the second set of two electrodes is used to bias the sensor and the first set of two electrodes is used to sense an output signal of the magnetic field sensor. The method is characterized in that at least one of the first or the second step is subdivided in at least a first sub-step and a second sub-step. A reference magnetic field has first magnetic field parameters, e.g. a first amplitude and/or direction, in the first sub-step and second magnetic field parameters, a second amplitude and/or direction, in the second sub-step.

Abstract: A resolver reference position adjustment method is capable of minimizing a detection error in the rotation angle of a rotor of a motor. In the resolver reference position adjustment method in which a reference position of a resolver of an axial double angle n mounted on an end of a shaft, to which the rotor of the motor is fixedly attached, for detecting rotation angles of the rotor is adjusted with respect to the rotor, the reference position of the resolver is adjusted by using the rotation angles of the rotor at a first point and at a second point, respectively, which are positions of the rotor apart an angle of (mechanical angle 180/axial double angle n) degrees from each other.

Abstract: Disclosed is a method for quantitatively determining the width of a soft zone area of a partially hardened metallic workpiece, which has at least one hardened and one unhardened area, by means of at least one multifrequency eddy current sensor. A single workpiece being individually is moved relative to the multifrequency eddy current sensor in such a manner that a spatially delimited eddy current field generated by the multifrequency eddy current interacts with the workpiece contactlessly, generates eddy currents therein which, in turn, generate a measuring signal in the multifrequency eddy current sensor, in which the spatially delimited eddy current field has a greatest extension oriented in longitudinal direction to the surface of the workpiece which extension is greater than the maximum extension of the soft zone area in longitudinal direction of the surface of the workpiece.

Abstract: Certain embodiments of the present invention provide systems and methods for electromagnetic calibration of an instrument. Certain embodiments provide an electromagnetic instrument calibration system including electromagnetic receiver electronics for receiving electromagnetic field information from an electromagnetic transmitter. The system also includes a calibration mount configured to position the electromagnetic receiver electronics stationary with respect to the calibration mount for calibrating an instrument having an electromagnetic transmitter using the calibration mount and the electromagnetic receiver electronics.

Abstract: Techniques for calibrating an electromagnetic logging tool equipped with a plurality of antennas, with at least one antenna having its axis at an angle with respect to a tool axis, include disposing a test loop about the tool such that an axis of the tool and a plane on which the test loop lies form a tilt angle that is between about 0 and 90 degrees. An induced signal is measured at one of the antennas by energizing another of the antennas. Embodiments analyze the induced signal corresponding to a max or min extrema associated with a coupling effect due to the test loop. In other embodiments a corrected signal is compared with a calculated signal.

Abstract: For the inspection of materials and the detection and characterization of hidden objects, features, or flaws sensors and sensor arrays are used to image form two-dimensional images suitable for characterizing the hidden features. Magnetic field or eddy current based inductive and giant magnetoresistive sensors may be used on magnetizable and conducting materials, while capacitive sensors can be used for dielectric materials. Enhanced drive windings and electrode structures permit nulling or cancellation of local fields in the vicinity of the sense elements to increase sensor sensitivity. The addition of calibration windings, which are not energized during measurements, allows absolute impedance and material property measurements with nulled sensors. Sensors, sensor arrays, and support fixtures are described which permit relative motion between the drive and sense elements. This facilitates the volumetric reconstruction of hidden features and objects.

Abstract: A method and system for calculation of rotation dependent parameters in a system that senses shaft rotation of a toothed speed wheel. The method includes determining the passing edges of multiple gear teeth on a rotating speed wheel; calculating rotational speed of the rotating machine based on the passing edges of multiple gear teeth of the speed wheel; calculating a rotation independent tooth spacing correction factor for each gear tooth on the rotating wheel; and correcting the calculated rotational speed of the rotating machine using the tooth corrections.

Abstract: An array of three-axis magnetometers used for dynamic magnetic anomaly compensation are located at the corners of a parallelopiped, with pairs of magnetometer outputs used to derive a magnetic anomaly gradient vector used to compensate a compass and/or the output of a gyroscope in an inertial management unit. The system may be used in a neutrally buoyant remotely operated vehicle to permit ascertaining of course and position in the absence of surface control signals.

Abstract: Disclosed are methods and systems for testing MEMS devices (e.g., interferometric modulators) so as to induce a moveable element to move from a first position to a second position and to detect the movement. The methods include applying an electrical current to the movable element in the presence of a magnetic field, thereby producing a Lorentz force on the movable element. The force required to move the movable element from the first position to the second position can then be estimated based on the magnitudes and geometric relationships of the electrical current and the magnetic field, and the geometry of the movable element. In some embodiments, the first position may be a movable element adhered to another surface (e.g., a layer on a substrate) due to stiction forces. In these embodiments, the stiction forces can be estimated.

Abstract: The present invention provides a method for measuring hydrogen concentration in an electrically conductive material, such as a nuclear fuel rod, comprising calibrating an eddy current probe at a plurality of hydrogen concentrations; measuring eddy currents at a plurality of positions along an electrically conductive material; and calculating a hydrogen concentration in the electrically conductive material at each of the positions along the electrically conductive material. The present invention also provides a system for measuring hydrogen concentration in a nuclear fuel rod, comprising an eddy current probe; a nuclear fuel rod calibration standard; a data handling system for collecting data generated by the eddy current probe and for performing calculations using the data. The system may be utilized in-situ and may comprise a movable probe mount configured to hold the eddy current probe and to traverse the calibration standard and the nuclear fuel rod to be measured.

Abstract: The methods and devices provide for calibration of two or three-axis magnetic field sensors with an artificial magnetic calibration field, or a sequence of magnetic calibration fields, that overwhelm the earth's magnetic field and any other extraneous magnetic fields that may be present in the calibration area. The calibration field or fields are produced with a known relationship to the test stand or jig on which a two and or three-axis magnetic field sensor is secured. The calibration fields are oriented to produce fields that have generally parallel lines of force (relative to the sensor to be calibrated) with minimal curvature or discontinuity. For each coil or calibration field, data from each sensor may be collected and analyzed to enable one or more correction factors to be determined for each sensor. The correction factors may be provided to the apparatus in which the magnetic sensor is secured to correct sensor data and provide more accuracy.

Abstract: The methods and devices provide for calibration of two or three-axis magnetic field sensors with an artificial magnetic calibration field, or a sequence of magnetic calibration fields, that overwhelm the earth's magnetic field and any other extraneous magnetic fields that may be present in the calibration area. The calibration field or fields are produced with a known relationship to a test stand or jig on which a two and or three-axis magnetic field sensor is secured. The calibration fields are oriented to produce fields that have generally parallel lines of force (relative to the sensor to be calibrated) with minimal curvature or discontinuity. For each coil or calibration field, data from each sensor may be collected and analyzed to enable one or more correction factors to be determined for each sensor. The correction factors may be provided to the apparatus in which the magnetic sensor is secured to correct sensor data and provide more accuracy.

Abstract: A measured physical quantity calculating part 41 calculates a measurement result-corrected value obtained by correcting a measurement result of a sensor unit 25 by the use of corrected values for the sensor unit 25. Subsequently, a measurement environment estimating part 42 estimates a terrestrial magnetism measurement environment on the basis of at least one measurement result-corrected value. The estimation result is displayed on a display unit 13 by an estimation result display part 43. In this way, the terrestrial magnetism measurement environment is first estimated and then the terrestrial magnetism is measured by the use of the sensor unit 25. That is, it is possible to measure the terrestrial magnetism by the use of a magnetic sensor mounted on a mobile information device after estimating the terrestrial magnetism measurement environment.

Abstract: A closed loop magnetic sensor system for measuring an input magnetic field from a magnetic field source has a compensation circuit, which can be for example a printed wire board, and a magnetic sensor, such as a Magnetoresistive (MR) sensor, for measuring an input magnetic field. Preferably, the magnetic sensor is magnetically coupled to the compensation circuit by arranging the magnetic sensor in an air gap provided in the compensation circuit. The compensation circuit has a compensating conductor, arranged on or in a dielectric medium, which can be configured as a plurality of nested coils. Electrical control circuitry, electrically, coupled to the magnetic sensor and compensating conductor, is adapted and arranged to drive a feedback current through the compensating conductor according to the output of the magnetic sensor such that the input magnetic field is substantially compensated at the magnetic sensor. The magnetic system can serve as current sensor for sensing current through a primary conductor.

Abstract: Sensor condition verification may be performed on electromagnetic sensors and sensor arrays mounted to a material surface. The sensors typically have a periodic winding or electrode structure that creates a periodic sensing field when driven by an electrical signal. The sensors can be thin and flexible so that they conform to the surface of the test material. Monitoring the conductivity changes of a test material, with changes in temperature, may provide a mechanism for testing the integrity of the sensor. Changes in the conductivity, due to changes in temperature, without significant lift-off changes may verify the calibration of the sensor and that the sensor elements themselves are intact.

Abstract: A probe card comprises a plurality of coils for impressing a magnetic field in changeable directions to a magnetic sensor and a group of probes for detecting an output signal of the magnetic sensor. A manufacturing cost of the magnetic sensor can be decreased.

Abstract: The invention relates to a field device and a method for calibrating a field device, having a field device electronics and a sensor unit for process measurements, wherein the field device electronics receives measurement signals of the sensor unit, wherein the field device electronics includes an evaluation unit for evaluating the measurement signals and means for calibrating the field device. According to the invention, the means for calibrating the field device includes a digital adjusting element and a microprocessor, wherein the digital adjusting element is driven by the microprocessor for calibrating the field device.

Abstract: The disclosed invention is a calibration device in magnetic sensor for inducting a magnetic scale which primarily comprises: a sensor unit which includes a Hall sensor to produce square signals when detecting the magnetic field generated by a magnetic scale; a signal display unit for presenting signals from said sensor unit; and signal display unit which has a display component for reflecting signal status of the sensor unit, and a signal output unit to transfer signals produced by the sensor unit into a set of Z and /Z signals for the measuring usage of the machine tool. By using this calibration device, a magnetic sensor produces signals to indicate an optimum clearance between a magnetic sensor and a magnetic scale whereon and presents this indication through the display unit to enable an operator to install the magnetic sensor correctly and promptly.

Abstract: A magnetic sensor package having a biasing mechanism involving a coil-generated, resistor-controlled magnetic field for providing a desired biasing effect. In a preferred illustrated embodiment, the package broadly comprises a substrate; a magnetic sensor element; a biasing mechanism, including a coil and a first resistance element; an amplification mechanism; a filter capacitor element; and an encapsulant. The sensor is positioned within the coil. A current applied to the coil produces a biasing magnetic field. The biasing magnetic field is controlled by selecting a resistance value for the first resistance element which achieves the desired biasing effect. The first resistance element preferably includes a plurality of selectable resistors, the selection of one or more of which sets the resistance value.

Abstract: The magnetic field generator device comprises a plurality of magnetic field generator units, which generate distinct magnetic fields in different locations, and at least two or more of these magnetic field generator units have different external shape, configuration or size. The magnetic field formed by such a magnetic field generator device is scanned by the probe device of a magnetic force microscope, and based on the measurement result, the probe device is calibrated.

Abstract: In a method of determining residual error compensation parameters for a magnetoresistive angle sensor providing a first measurement signal depending on a rotational angle the step of generating a plurality of value pairs for a plurality of rotational angle values is provided, wherein each value pair has a rotational angle value and an associated measurement signal value. The method further includes ascertaining a sinusoidal fit function the course of which is adapted to the plurality of value pairs. Finally, residual error compensation parameters can be generated from a difference between the ascertained sinusoidal fit function and the associated measurement signal values of the measurement signal for the plurality of rotational angle values.

Abstract: A method of determining the thickness of a conductive film is disclosed. The method employs measured voltage and current responses that have been temperature-compensated to determine the thickness of the conductive film. The temperature compensation uses a temperature compensation factor obtained from a calibration substrate different from the target substrate on which the conductive film being measured is disposed. The calibration substrate has a conductive film formed of a conductive material that is substantially similar to the conductive material of the target substrate.

Abstract: By breaking the calibration into two parts—one calibration offset being associated with a first portion, and the other calibration offset being associated with a second portion, it is possible to combine the various calibration offsets for a particular first portion mated with a particular second portion. Thus, any one of a number of downhole first portions can be combined, on a session-by-session basis, with any number of second portions. In one embodiment, the second portion calibration is specific to the particular second portion, and in another embodiment the calibration for a second portion is a fixed calibration offset that is based on a second portion type, such as the second portion size.

Abstract: An apparatus-based method is disclosed for calibration of a 3D field sensor. The method includes accessing a plurality of samples, where the samples are from the 3D field sensor. Each sample represents a magnitude and an orientation of a three-dimensional field sensed by the 3D field sensor. Using the plurality of samples, a plurality of parameters is determined of an ellipsoid. The determination of the plurality of parameters is performed so that the ellipsoid fits the plurality of samples. A transformation is determined that transforms the ellipsoid into a sphere. The transformation is applied to a sample to create a transformed sample. Apparatus and signal bearing media are also disclosed.

Abstract: A method and system for orienting and calibrating a magnet for use with a speed sensor. A magnet can be mapped two or more planes thereof in order to locate the magnet accurately relative to one or more magnetoresistive elements maintained within a speed sensor housing. An optical location of the magnet with respect to the magnetoresistive element and the sensor housing can then be identified in response to mapping of the magnet. Thereafter, the magnet can be bonded to the speed sensor housing in order to implement a speed sensor thereof maintained by the speed sensor housing for use in speed detection operations.

Abstract: With a method for the contactless determination of a thickness of a layer (20) made of electrically-conductive material of a component (17), a sensor composed of a coil form (13) and a coil (14) is positioned in the vicinity of the component (17) to be measured. The method is based on a combination of the principles of induction and eddy current. The thickness of the layer (20) is determined using a plurality of measuring and evaluation steps in which the coil (14) is acted upon with a first alternating current frequency f and its inductance and resistance values are evaluated. The distance between the coil form (13) and, therefore, the coil (14), and the component (17) is derived from the resistance value R of the coil (14) acted upon with alternating current frequency f.

Abstract: A magnetic field sensor for the measurement of at least one component of a magnetic field comprises a ferromagnetic core that serves as a magnetic field concentrator, an excitation coil and a read-out sensor. The read-out sensor preferably comprises two sensors arranged in the vicinity of the outer edge of the ferromagnetic core and measures the at least one component of the magnetic field. The ferromagnetic core is ring-shaped or disc-shaped. On operation of the magnetic field sensor, a current is temporarily applied to the excitation coil in order to bring the ferromagnetic core into a state of predetermined magnetization in which the magnetization of the ferromagnetic core produces no signal in the read-out sensor.

Abstract: A magnetic calibration device comprises a mount supporting a magnetic sensor card being detachably attached and comprising at least one magnetic sensor to be calibrated and connected to a first analog electronic circuit with a current source and a first analog to digital converter. A coil card is further detachably attached and comprises three coils arranged substantially orthogonal to each other and connected to a second analog electronic circuit with a second analog to digital converter. A connection such as a cable or a wireless link provides a supply voltage to the first and second analog electronic circuits, respectively, and guides digital signals from the first and second analog to digital converters, respectively, to at least one processing unit. A magnet generates a substantially homogeneous and constant calibration magnetic field, and a rotator rotates said cards in said calibration magnetic field around two substantially orthogonal axes.

Abstract: With a method for the contactless determination of a thickness of a layer (20) made of electrically-conductive material of a component (17), a sensor composed of a coil form (13) and a coil (14) is positioned in the vicinity of the component (17) to be measured. The method is based on a combination of the principles of induction and eddy current. The thickness of the layer (20) is determined using a plurality of measuring and evaluation steps in which the coil (14) is acted upon with a first alternating current frequency f1 and a second alternating current frequency f2, and its change in inductance is evaluated. The distance between the coil form (13) and, therefore, the coil (14), and the component (17) is derived from the inductance value of the coil (14) acted upon with the second alternating current frequency f2.

Abstract: A vehicle control system with user-guided calibration is presented. In one embodiment, a vehicle control system is presented comprising an output device and circuitry operative to provide an output, via the output device, that guides a user through a plurality of calibration steps in a particular order. The circuitry can additionally or alternatively be operative to determine which of the calibration steps, if any, to present as a next calibration step based on whether a given calibration step is successful. Other embodiments are provided, and each of the embodiments can be used alone or in combination with one another.

Abstract: A test procedure and a metal detector having transmitting coils, receiving coils and an electronic processing circuit adapted to detect variations in the signals received by the receiving coils against a reference value. The metal detector, also includes a test module which has a selector able to detect a test request, and a controller, used when a test request is detected by the selector, able to compare the signals from the receiving coils during the subsequent passing of a known standard reference object with a predetermined response through the detector.

Abstract: A control device 200 calibrates a magnetic-field sensor 100 by computation. A computation unit 210 calculates the magnetic-field intensity based upon the outputs of X-axis, Y-axis, and Z-axis magnetic-field detection devices of the magnetic-field sensor 100. Such calculation is performed for four or more different points. The calculation is performed such that at least one point is not positioned on a plane including the other points. The computation unit 210 converts the outputs from the X-axis, Y-axis, and Z-axis magnetic-field detection devices of the magnetic-field sensor 100 into three-dimensional spatial coordinate points. Then, the computation unit 210 creates a sphere on which the four or more coordinate points thus obtained are positioned. The coordinate point of the center of the sphere thus created represents the magnetic-field offset.

Abstract: In a circuit arrangement having a linear variable differential transformer as a displacement sensor or force sensor, having a selection circuit which is connected to the primary coil of the transformer and which provides an output current for triggering the primary coil, and having an analysis circuit which is connected to the secondary coils of the transformer and which provides a message signal, a control circuit used for triggering the selection circuit and the analysis circuit and for processing the measurement signal provided by the analysis circuit is connected to the primary coil in order to calculate the temperature of the circuit arrangement, and is configured such that it determines the temperature-dependent ohmic resistance of the primary coil and calculates from it the temperature and corrects accordingly the measurement signal provided by the analysis circuit.

Abstract: An apparatus for inspecting a metallic post contoured in a single dimension for defects. The apparatus has a clamp having at least one jaw with a surface conforming to the contour to the metallic post. The conforming jaw or jaws also have a plurality of eddy current coils and the probe has at least one sensor configured to sense at least one of position or motion.

Abstract: A sensor and method that detects a mis-calibration and automatically recalibrates itself without operator intervention. If the sensor determines that it was calibrated over an object such as a stud, the sensor may automatically update the calibration value with a new lower value without operator intervention. This process may repeat until the calibration value is set to a value that represents the wall covering alone without hidden objects behind it.

Abstract: Inductive sensors measure the near surface properties of conducting and magnetic material. A sensor may have primary windings with parallel extended winding segments to impose a spatially periodic magnetic field in a test material. Those extended portions may be formed by adjacent portions of individual drive coils. Sensing elements provided every other half wavelength may be connected together in series while the sensing elements in adjacent half wavelengths are spatially offset. Certain sensors include circular segments which create a circularly symmetric magnetic field that is periodic in the radial direction. Such sensors are particularly adapted to surround fasteners to detect cracks and can be mounted beneath a fastener head. In another sensor, sensing windings are offset along the length of parallel winding segments to provide material measurements over different locations when the circuit is scanned over the test material.

Abstract: A speed meter unit has a magnetic pointer position detector, including an output coil, a detection coil and a magnetic piece. The output coil generates magnetic flux. The detection coil is for detecting the magnetic flux from the output coil. When a pointer has returned to an initial position, the magnetic flux generated in the output coil can reach the detection coil through the magnetic piece, so that a microcomputer can detect the initial position of the pointer. Such the magnetic pointer position detector is resistive to the soil or the oxidization, so that the speed meter unit can detect the initial position of the pointer accurately and securely.

Abstract: A method for balancing the flux density of a permanent magnet includes sensing flux density in a permanent magnet and if unbalanced relative to a physical center, adjusting the cross-sectional area and shape of the magnet by removing magnetic material from the magnetic pole with the stronger magnetic flux density. This method is repeated until the magnetic flux density is balanced between the opposite poles of the permanent magnet relative to the physical center.

Abstract: A device for automatically detecting a calibration termination of a geomagnetic sensor includes a detection unit for detecting signals X and Y outputted from X-axis and Y-axis coils of the geomagnetic sensor, respectively, a calculation unit for calculating slopes dX/dt and dY/dt of the signals X and Y, respectively, and the number of sign changes Nx and Ny of the slope dX/dt of the signal X and the slope dY/dt of the signal Y, respectively, a display unit for displaying the calibration termination and a calibration progress state for the geomagnetic sensor, and a control unit for outputting a driving signal to the display unit to display a state of the calibration termination based on the slope dX/dt of the signal X and the slope dY/dt of the signal Y and the number of slope sign changes Nx and Ny.

Abstract: The present invention provides an apparatus for processing a sheet. When a medium having various patterns detected by a plurality of detecting sections for individually detecting plural kinds of features from a sheet, each detecting section detects plural kinds of features from the medium. The features detected from the medium are compared with a predetermined reference value so that the condition of the apparatus can be judged.

Abstract: A device for measuring magnetic field(s). The device includes at least one measurement acquisition pathway including a measurement current generator, a coil, a measurement resistor, at least one amplifier, and at least one antialiasing filter, delivering a measurement voltage. The device for measuring magnetic field(s) includes a device for determinating at least one electrical quantity representative of the acquisition pathway. The device for determining includes a mechanism for injecting a predetermined calibration current, including at least two frequency terms at at least two frequencies distinct from those of a measurement current, the calibration current being superimposed on the measurement current. The device for measuring magnetic field(s) also includes a calculation device delivering an estimate of the at least one electrical quantity at the frequency or frequencies of the measurement current.

Abstract: An instrument and method for providing accurate and reproducible measurement of absolute properties of a material under test without using conductivity or crack calibration standards. The instrument has a sensor designed to minimize unmodeled parasitic effects. To accomplish this, the sensor has one or more of the following features: dummy secondary elements located at the ends of a primary winding meandering, setting back of the sensing element from a connecting portion of the primary winding, or various grouping of secondary elements. The sensing elements of the sensor can be connected individually or in differential mode to gather absolute or differential sensitivity measurements. In addition, the instrumentation is configured such that a significant portion of the instrumentation electronics is placed as close to the sensor head to provide independently controllable amplification of the measurement signals therein reducing noise and other non-modeled effects.