Abstract: A configuration comprising a magnetic sensor and a pointing control circuit, for implementing a pointing device, is rendered compact in size. To that end, the pointing control circuit is formed in the central part of an IC chip, substantially square in shape, and Hall elements are provided in four corners of the peripheral region of the pointing control circuit, respectively, thereby forming the magnetic sensor, comprising the Hall elements, integrally with the pointing control circuit. Further, the Hall elements are formed integrally with the pointing control circuit in the step of fabricating an IC, thereby uniting the Hall elements with the pointing control circuit.

Abstract: The present invention provides a method and apparatus for performing resistivity measurements for the purpose of geo-steering with 180-degree azimuth resolution. All the measurements represent a complementary set of data acquired in two operational modes. The directional mode providing sensitivity of the received signals to the azimuth characteristics of the formation. The deep mode provides a large depth of investigation for resistivity determination and bed boundary detection. The directional mode can be implemented using one receiving coil placed in between quadruple type transmitter. The deep mode represents either array induction measurements or multiple propagation resisitivity (MPR) measurements that provide high depth of investigation for resistivity determination and bed boundary detection.

Abstract: A well logging tool includes a conductive mandrel; an antenna array disposed around the conductive mandrel, wherein the antenna array comprises a plurality of antennas disposed on insulating supports and at least one contact spacer, the at least one contact spacer having at least one conductor channel having a contact assembly disposed therein; and a sleeve disposed over the antenna array, wherein the sleeve includes at least one electrode, the at least one electrode and the contact assembly adapted to provide a radially conductive path from an exterior of the well logging tool to the conductive mandrel.

Abstract: A proximity sensor is carried within a small diameter package and includes a magnet for providing a desirable magnetic field for operation of proximity sensing circuitry carried along a central axis to allow for a maximum sensor signal output with no change due to a relative rotation angle between the sensor and a target being monitored. Electrical contact pins include an offset positioned near the central axis for permitting a desirable small gauge insulated wire to be connected the sensor.

Abstract: A first magnetic substance and a second magnetic substance are arranged opposite to each other with a gap left therebetween; a holding member being arranged in the gap; a magnetic field generator being secured to the holding member; the generator being arranged adjacent to the first magnetic substance or the second magnetic substance, thereby increasing an magnetic attraction generated by a magnetic force between the generator and the first magnetic substance or the second magnetic substance. A slide between a sliding portion of a supporting member and that of the holding member is permitted only on the magnetic substance side to which the magnetic field generator stands close, which relaxes the requirements of dimensional accuracy such as the height of the holding member.

Abstract: A rotation angle detection device is simple in structure and is capable of reducing the size of a permanent magnet. The permanent magnet is fixedly secured to a rotating member. A first guide member is attached at one end face to an S pole side of the permanent magnet. A second guide member is attached at one end face to an N pole side of the permanent magnet, and has its tip end disposed in opposition to a tip end of the first guide member. A magnetoresistive member is disposed in a space between the tip ends of the first and second guide members, the magnetoresistive member being fixedly attached to a non-rotating member. An angle of rotation of the rotating member is detected by detecting a change of the azimuth of magnetic flux, which is generated by the permanent magnet in the space, by means of the magnetoresistive member.

Abstract: A scanning magnetic microscope (SMM) (20) includes a current source (27) for imposing an excitation current to a conductor-under-test (CUT) (70) and, if applicable, a reference current to a proximally located reference conductor (72). During accelerated testing, the SMM (20) corrects thermal drift of the CUT (70) via the reference conductor (72). A sensor (21) may be cooled by a heat sink (31) such as a pump (33) directing an airstream or a coldfinger (80). The sensor may switch from a contact to a non-contact mode of scanning the CUT (70). The SMM (20) and methods are useful for measuring electromigration in a CUT (70) as it occurs, for assembling the images into time lapsed representations such as a shape of the CUT (70), for measuring electromigration as a function of a cross sectional area of a wire under a dielectric material (DM) (78), for determining electrical parameters of the CUT (70), and for optimizing a thickness of a DM (78) over a CUT (70).

Abstract: A rotational-rate sensor is provided which includes a detecting element, a circuit portion, an airtight container and an elastic body, in which: the synthetic resonance-frequency of a machine system of the rotational-rate sensor and the frequency of an applied rotational rate which corresponds to the difference between the resonance frequency in the direction where the detecting element is driven and the resonance frequency of the detecting element in the direction where the detecting element detects a rotational rate, are each lower than each of the resonance frequency in the direction where the detecting element is driven and the resonance frequency in the direction where the detecting element detects a rotational rate; and the cut-off frequency of the low-pass filter in the circuit portion is lower than each of the synthetic resonance-frequency and the frequency of the applied rotational rate.

Abstract: The invention relates to a device and a method for the contact-free measurement of rotary and/or linear movements of components moving in relation to one another; and a device for the contact-free measurement of rotary and/or linear movements of components moving in relation to one another utilizing a Giant Magnetic Resistor (GMR) cell and at least one magnetic element, and an evaluation unit, in which two delivery voltages with mirror-image profiles are generated by the magnet element, moved in relation to said GMR cell.

Abstract: A method of improving pulse inductive metal detector sensitivity by minimizing adverse ground responses and transmitter coil transients is disclosed. The method provides a calibration mode for a typical pulsed EMI metal detector. The purpose of the calibration mode is to determine and record a nulling signal representative of the transmitter coil coupling to the receiver coil and a ground response that has no metal. The nulling signal is then used during normal operation of the metal detector by combining it with the instant receiver coil signal in a difference amplifier. The difference amplifier effectively subtracts the nulling signal from the instant signal yielding a response signal that has removed the ground response that may be present in the instant signal. The metal detector can be periodically re-calibrated. It may also be re-calibrated upon discovery of a metal target to provide the most up to date nulling signal for the ground around the metal target.

Abstract: A passive blade detection sensor exploits the electrically conductive trait of typical turbo machinery components such as fan, compressor and turbine blades. A permanent magnet is placed strategically adjacent to a wire coil to generate a single pulse/antipulse signal when a blade passes in front of the sensor. The electrically conductive blade allows eddy currents to flow briefly as it passes through the magnetic field, the local reluctance is momentarily increased, and the magnetic field is momentarily changed. The coil is sensitive only to the portion of change through its cross section, so that a simple voltage pulse, useful for precise timing of blade passage, is produced. Since the device is only sensitive to fast changes in local conductivity, blades can be detected through non-ferrous barriers such as typical engine case walls.

Abstract: The invention relates to apparatus for examining magnetic properties of objects, in particular sheet material, such as bank notes (20). The apparatus comprises a magneto-optic layer (10) whose optical properties are influenceable by the magnetic properties of the sheet material (20), a light source (11) for producing light that is coupled into the magneto-optic layer (10), and a detector (13) for detecting light that is transmitted and/or reflected by the magneto-optic layer (10). For reliable examination of the magnetic properties of sheet material it is provided that the direction of propagation of the coupled-in light extends parallel to a base surface (9) of the magneto-optic layer (10). The invention permits the magnetic properties in particular of sheet material with areas emitting very weak magnetic fields to be examined with very high sensitivity and reliability.

Abstract: Disclosed is a magnetostrictive transducer for generating and receiving elastic waves in a testing plate and an apparatus for structural diagnosis using the magnetostrictive transducers. More particularly, disclosed is a magnetostrictive transducer which may generate and transmit elastic waves using the magnetostrictive effect in any directions without re-attaching ferromagnetic patch on the non-magnetic testing plate and may produce Lamb waves and Shear Horizontal (SH) waves in desired directions, and an apparatus for structural diagnosis using the magnetostrictive transducers. There is provided a magnetostrictive transducer comprising: a patch made of ferromagnetic material; and a magnetic field generator for generating magnetic field applied to the patch, the magnetic field generator being placed on the patch, wherein the magnetic field generator comprises: a main body; two magnets for generating bias magnetic field, the magnets being apart from each other; and a coil for winding around the magnets.

Abstract: The present invention relates to a method of investigating the wall (2) of a borehole in a geological formation by means of two injectors (4, 5) with a potential V being applied between them and in measuring the potential difference ?V between two electrically isolated measurement electrodes (6) situated between the two injectors (4, 5) and spaced apart from the formation by an insulating layer (1), in which the resistivity of the formation is obtained from the measured values of ?V, V and I, with corrections being made for the effects due to the nature and the thickness of the insulating layer (1). In a first variant these corrections are based on a correction factor obtained from curves of K=Rt.I/?V as a function of the impedance V/I of the injector. In a second variant these corrections are obtained by estimating the current IF actually injected into the formation while taking account of leakage current IL, and calculating the resistivity of the formation from the equation (I).

Abstract: A detector to determine the peak-to-peak value of a signal is presented. The detector includes a first circuit to provide a tracking signal that tracks a positive slope of the signal during a first time interval and a negative slope of the signal during a second time interval. The detector further includes a second circuit configured to produce values associated with the tracking signal provided during one of the first and second time intervals, where one of the values is indicative of the peak-to-peak value of the signal.

Abstract: The invention relates to a device for setting an operating point of a magnetic field sensor having a periodic characteristic, in particular for a device for detecting a magnetic field and/or flux, having a SQUID as magnetic field sensor and a control unit which is connected downstream of the SQUID, has a control time constant (t) and has a feedback loop which acts on the SQUID and is designed such that it is active about a number of operating points of the SQUID, where flux quantum pump means are provided which are assigned to the SQUID, have a signal generation unit for generating a control and/or regulation signal for the SQUID and are designed such that, in order to pump at least one flux quantum into and out of the SQUID, a signal form of the control and/or regulation signal, generated by the signal generation unit, is different and, referred to a rising and a falling edge of a signal form, is unsymmetrical, where in each case only one of the edges of a signal form is short referred to the control time co

Abstract: Tracking a boring tool is performed within an underground region using a locating signal. The boring tool is moved through the ground during a series of distance movements such that potential movement of the boring tool during any one of the distance movements is less than a maximum movement value. A current positional relationship is determined for a current one of the distance movements based on: a last-determined positional relationship established for an immediately preceding one of the distance movements, certain orientation parameters, the maximum movement value and the determined signal strength of the locating signal in the current positional relationship. Target coordinates are accepted and a target position, based on the target coordinates, is included as part of the current positional relationship. The position of the target is unconstrained with respect to system geometry. Steering command features are provided along with steering warnings.

Abstract: A modified hybrid Hall effect device is provided which is the combination of a conventional Hall effect device and a second Hall effect device having a Hall plate coupled to a ferromagnetic layer. The hybrid Hall effect device can be used to determine the independent magnetic field vector components comprising a vector magnetic field, such as for determining the {circumflex over (x)} and the {circumflex over (z)} components of a magnetic field, or for measuring the total magnitude of a vector magnetic field of any orientation. The modified Hall Effect device can be adapted for use as a magnetic field sensor for the detection of macroscopic objects that have associated magnetic fields, or for microscopic objects that have been tagged by microscopic magnetic particles.

Abstract: The invention relates to a method of mapping subsurface resistivity contrasts by making multichannel transient electromagnetic (MTEM) measurements on or near the earth's surface using at least one source, receiving means for measuring the system response and at least one receiver for measuring the resultant earth response. All signals from the or each source-receiver pair are processed to recover the corresponding electromagnetic impulse response of the earth and such impulse responses, or any transformation of such impulse responses, are displayed to create a subsurface representation of resistivity contrasts. The invention enables subsurface fluid deposits to be located and identified and the movement of such fluids to be monitored.

Abstract: A method for evaluating measuring signals of an electromagnetic field is disclosed which is in interaction with an electrically conductive fluid for detecting components in the fluid which differ from the electric conductivity of the fluid, with the measuring signals being divided into at least two channels and being evaluated in order to detect different distributions and concentrations in the fluid.