Abstract: This invention relates to magnetic inductance tomography, and in particular, to coils of a sensor/driver coil array for use in a magnetic inductance tomography apparatus, in which driver/sensor coils are used to measure the induced flux in a conductive, dielectric and permittivity body, such as the human body. The sensor/driver coil array comprises at least one layer of thin coils whose centers are arranged on a regular grid, with adjacent coils overlapped by a suitable distance to cancel inductive neighbor coupling between them.

Abstract: A combined electromagnetic and magnetometer detection system for detecting objects. The system includes a primary electromagnetic transmitter for generating a primary magnetic field; an electromagnetic sensor for sensing secondary magnetic fields generated by a target region subjected to the primary magnetic field; a magnetometer sensor substantially centered at a center of the primary magnetic field; a compensation transmitter for generating a compensating magnetic field that substantially negates the primary magnetic field across the magnetometer sensor; and a signal generator electrically connected to the primary electromagnetic transmitter and the compensation transmitter for driving the transmitters to generate the primary magnetic field and the compensating magnetic field, respectively.

Abstract: Methods and apparatus for testing electrical storage batteries monitor magnetic susceptibility of components of the storage batteries. In some embodiments, magnetic susceptibility of a plate in a lead-acid battery is determined to provide an indication of the state of charge of the battery.

Abstract: A probe for eddy current monitoring of the surface of a circumferential slot formed in a turbojet disk. The probe includes a stem fastened to a support and a first multi-element sensor constrained to move with the stem and configured to be inserted into the circumferential slot to perform the inspection, and a second multi-element sensor. The two multi-element sensors are disposed back to back, and the stem of the probe is mounted to pivot about its own axis to enable the two multi-element sensors to be inserted in the slot.

Abstract: An electromagnetic impedance sensor detects an object made of conducting material or soft magnetic material with contact-free. The sensor includes: a detection coil; and a detection circuit for supplying electricity to the coil and for measuring electromagnetic impedance change in the coil. The detection coil includes multiple coil portions provided by one wire. One coil portion has a side adjacent to a corresponding side of another coil portion. The side and the corresponding side extend along with a direction, and the side has a current flowing direction, which is the same as the corresponding side.

Abstract: An electromagnetic detection system comprising: a transmitter loop for generating a primary magnetic field, and a first pair of spaced apart receiver coils and second pair of spaced apart receiver coils for measuring a secondary magnetic field generated in response to the primary magnetic field. The transmitter loop drives the transmitter to generate the primary magnetic field.

Abstract: A system for determining magnetic permeability of a material. Two electrical inductors formed as primary and secondary concentric coils share a common magnetic core space. A first AC voltage applied to the primary coil creates a magnetic flux in the core proportional to the magnetic permeability of the material. The magnetic flux induces an AC voltage in the secondary coil indicative of the apparent magnetic permeability of the sample. The apparent permeability is corrected for conductivity by imposing a second AC voltage and resistor in series across first and second electrodes disposed in the material. When the material is a magnetorheological fluid, the magnetic permeability is proportional to the concentration of magnetic particles in the sample and can be back-calculated from the amplitude of the secondary voltage signal.

Abstract: Described are methods for monitoring of stresses and other material properties. These methods use measurements of effective electrical properties, such as magnetic permeability and electrical conductivity, to infer the state of the test material, such as the stress, temperature, or overload condition. The sensors, which can be single element sensors or sensor arrays, can be used to periodically inspect selected locations, mounted to the test material, or scanned over the test material to generate two-dimensional images of the material properties. Magnetic field or eddy current based inductive and giant magnetoresistive sensors may be used on magnetizable and/or conducting materials, while capacitive sensors can be used for dielectric materials. Methods are also described for the use of state-sensitive layers to determine the state of materials of interest. These methods allow the weight of articles, such as aircraft, to be determined.

Abstract: The present invention is a method and an eddy current system for non-contact determination of the resistance between the current lead stripe and the coating during continuous fabrication of chemical power sources such as batteries, supercapacitors, photovoltaic modules and the like. Both the method and the non-destructive test system for practicing the method are described. The method includes placing of an integrated measuring transducer containing two strap-type eddy current probes above the surface of the coating applied to the metallic current lead stripe in the region of the shaft guiding the stripe movement, so that all the points of the operating surface of the transducer being at an equal distance from the stripe surface coating so that the two probes would take measurements on the same area of the coating.

Abstract: The invention provides for a method for determining the relative position of at least two magnetic actuator coils (2,3,3?) in a sensor, said coils being arranged on substantially opposite sides of a sensor cartridge (1). By measuring the electromagnetic induction of one of the coils, the relative positions of the coils in the sensor device is determined. Based on the determined relative positions, these positions may be adjusted. Alternatively, the actuation currents in the magnetic coils may be adjusted based on the determined relative positions. Furthermore, a sensor device comprising a sensor cartridge, at least two magnetic coils arranged on substantially opposite sides of the sensor cartridge, and measuring means for determining the electromagnetic induction is provided.

Abstract: The invention concerns a system suited for carrying out eddy current measurements on components for nuclear reactors when these components are located in water. The system comprises a control unit, a measurement probe and a first cable suited to constitute at least a part of the connection between the control unit and the measurement probe. The system also comprises a switching unit, suited to be located in water and arranged to be connected with said first cable, and to be connected with the measurement probe. The switching unit has a switching device which can assume at least a first and a second state. In the first state, the first cable is connected with the measurement probe. In the second state, the first cable is not connected with the measurement probe. The invention also concerns the use of the system.

Abstract: A system and method for refueling unmanned aerial vehicles. The system is adapted to refuel a first unmanned aerial vehicle from a second unmanned aerial vehicle and includes an arrangement for flying the first and second vehicles to proximity within a predetermined range and for connecting an umbilical from the second vehicle to the first vehicle in flight. In the illustrative embodiment, the arrangement for connecting includes a targeting system for electromagnetically detecting a refueling receptacle on the first vehicle. The targeting system includes a first coil around a refueling receptacle on the first vehicle. A seeker is disposed at a first end of said umbilical on the second vehicle. The seeker includes three detector coils adapted to detect a magnetic signal from the first coil around the receptacle on the first vehicle. The coils are mounted such that the detector coils point in different directions.

Abstract: The invention provides a drive coil and measurement probe comprising the drive coil. The measurement probes can be used, for example, in in-situ, non-destructive testing methods, also provided herein.

Abstract: A method for evaluating an electrode material for a non-aqueous electrolyte secondary battery including the steps of: (A) vibrating an electrode material for a non-aqueous electrolyte secondary battery at a prescribed frequency successively in two or more levels of magnetic fields that have different magnetic flux densities; (B) detecting induced magnetizations that are synchronous with the vibrations generated in the electrode material; and (C) determining saturation magnetization of the electrode material from the induced magnetizations.

Abstract: Test structures, systems, and methods for semiconductor devices are disclosed. In one embodiment, a test structure for a semiconductor device includes a winding disposed in at least one conductive material layer of the semiconductor device. At least a portion of the winding extends proximate a perimeter of the semiconductor device. The winding includes a first end and a second end. A first test pad is coupled to the first end of the winding, and a second test pad is coupled to the second end of the winding.

Abstract: Disclosed is a method of analysing a magnetic material which includes the construction of a signature S(H) of the magnetic material formed from at least two points S(H)P, this construction including obtaining the value of each point S(H)P by measuring, over each period fraction, the amplitude and possibly the phase of a harmonic of the magnetic field induced in the magnetic material, said amplitude and phase being obtained in response only to an excitation during this period fraction, the harmonic having a frequency nfH, where n is a non-zero positive integer; and the identification and/or the determination of the mass of the magnetic material from several points of the constructed signature S(H).

Abstract: At least one time-varying signal is applied to a plurality of coil elements in cooperative relationship with and spanning different portions of a vehicle. The coil elements generate an associated plurality of magnetic field components that interact with the vehicle. At least one detection circuit generates a detected signal responsive to signal components from the coil elements so as to provide for detecting a change in a magnetic condition of the vehicle.

Abstract: At least one time-varying signal is applied to a plurality of coil elements in cooperative relationship with and spanning different portions of a vehicle. The coil elements generate an associated plurality of magnetic field components that interact with the vehicle. At least one detection circuit generates a detected signal responsive to signal components from the coil elements so as to provide for detecting a change in a magnetic condition of the vehicle.

Abstract: Disclosed is a method of appropriately and easily selecting a combination of two different frequencies of an AC exciting signal used for eddy current measurement while decreasing or removing the dependence of the measurement accuracy on temperature. Three or more AC exciting signals of different frequencies are applied to an object under measurement by an exciting coil, and an induced current is produced. Detection signals corresponding to the frequencies are detected by a detection coil, and the phase difference between each detection signal and the AC exciting signal corresponding to each frequency is calculated from the detection signals corresponding to the frequencies. From the phase differences, a combination of two frequencies the phase differences of which are within a predetermined range is extracted. The lower frequency of the extracted combination is used for a first frequency, and the higher one is used as a second frequency. Thus, the combination of two frequencies are selected.

Abstract: Coil is made to be disposed with gap opposed to the surface of wafer, and wafer stage is made to move in X and Y direction and R and ? direction. When supplying an alternating current to coil with the frequency swept by impedance analyzer, the magnetic field made to be induced in coil will operate on the conductive film of wafer. By changing a parameter (a frequency or an angle) influencing the skin effect of the conductive film and giving the parameter to coil, the state where a magnetic field is not made to penetrate relatively the film of wafer and the state where the magnetic field is made to penetrate relatively the film can be formed. From the variation of various values corresponding to the eddy current induced based on the change of state influenced by the skin effect of the conductive film, the film thickness of wafer can be measured with sufficient accuracy.

Abstract: A method and device for forecasting/detecting a polishing end point and for monitoring a real-time film thickness to suppress Joule heat loss due to the eddy current to the minimum, to precisely forecast/detect a polishing end point, to precisely calculate the remaining film thickness to be removed, and polishing rate.

Abstract: A vibration and condition monitoring system with true digital signal processing based design, with very limited analog based general signal conditioning and integrated specific sensor conditioning and sensor power supply options. The device supports direct connection of eddy current probe systems to the module, due to a built-in driver and linearization functionality. Linearization and compensation of a specific eddy current probe/cable system is done by measuring its far/infinite gap response. This response is then according to the invention recalculated into a linearization curve/transfer function. Specific sensor signal conditioning is not dependent on hardware, but only on embedded software (firmware). There is full sensor input support in an I.S. environment. Not only the common sensor input types from accelerometer, velocity sensor or eddy current probe system for both vibration and/or speed measurements.

Abstract: Testing an electrical component, the component including a printed circuit board (‘PCB’) with a number of traces, the traces organized in pairs with each trace of a pair carrying current in opposite directions and separated from one another by a substrate layer of the PCB, where testing of the electrical component includes: dynamically and iteratively until a present impedance for a pair of traces of the component is greater than a predetermined threshold impedance: increasing, by an impedance varying device at the behest of a testing device, magnetic field strength of a magnetic field applied to the pair of traces by the impedance varying device, including increasing the present impedance of the pair of traces; measuring, by the testing device, one or more operating parameters; and recording, by the testing device, the measurements of the operating parameters.

Abstract: A method and device for forecasting and detecting a polishing endpoint and real time film thickness monitoring capable of suppressing to a minimum Joule heat loss due to an eddy current, and precisely forecasting and detecting the polishing endpoint, and precisely calculating a remaining film amount to be removed and a polishing rate. A high frequency inductor sensor is positioned close to the conductive film, and monitors a flux change induced in the conductive film. When a film thickness becomes a film thickness corresponding to a skin depth of the conductive film a method of calculating on the spot a polishing rate and a remaining film amount to be removed is provided.

Abstract: A method for forecasting a polishing end time or point, wherein an inductor 36 in a sensor is placed adjacent to the conductive film 28. The magnetic flux formed by the inductor 36 is monitored, and a change of magnetic flux induced in the conductive film 28 is detected. Based on the skin effect of the material of the conductive film 28 as a factor, a process is used in which an eddy current formed with the decrease of the film thickness by polishing increases and a process in which the eddy current formed with the decrease of the film thickness substantially decreases when the polishing is progressed. Based on the characteristic change of the magnetic flux induced in the conductive film 28, the polishing end point is forecasted, and at the same time, the magnetic flux induced in the conductive film 28 is alleviated or turned off.

Abstract: A vibration canceling circuit for a metal detector. The metal detector includes a transmit coil, first and second receive coils, a differential circuit coupled to the first and second receive coils, a controller coupled to the differential circuit, and a vibration canceling circuit coupled to the controller. The controller uses a signal provided by the vibration canceling circuit to remove a vibration component from a metal detection signal.

Abstract: Disclosed is a method of analysis of a mixture of biological and/or chemical components that entails spatially arranging a chosen component attached to magnetic particles, exposing the particles to a magnetic field, and recording a magnetic induction signal, from which the content of the analyte in the mixture is judged; this includes grouping the chosen component in a probe volume, making the magnetic field alternating, pre-setting its spectrum, at least, at two frequencies, and recording the signal at a frequency, which is a linear combination of these frequencies, during the exposure of the magnetic particles to the field.

Abstract: A magnetic field generated by at least one coil operatively associated with a first portion of a vehicle responsive to a first signal from a signal source causes an eddy current in at least one conductive element operatively associated with or at least a part of a second portion of the vehicle. In one aspect, a circuit operatively coupled to the at least one coil generates a second signal responsive to a self-impedance of the at least one coil, wherein the second signal is at least partially in-phase with the first signal. In another aspect, a magnetic sensor is responsive to an eddy current in the at least one conductive element. In yet another aspect, the at least one conductive element comprises a metal sheet, film or coating of paramagnetic or diamagnetic material that is relatively highly conductive.

Abstract: An acoustic sensor comprises at least one resonant element. A driver comprises an electrical coupling means and an electromagnetic field source arranged such that the electrical coupling means transfers currents to the electromagnetic field source. The electromagnetic field source produces an electromagnetic field that drives the resonant elements to produce acoustic waves directed to a predetermined part of a test sample. Also provided is an electromagnetic detector for receiving the acoustic spectrum omitted from a test sample and an electrical circuit connected to the drive around detector.

Abstract: This invention relates to magnetic inductance tomography, and in particular, to coils of a sensor/driver cail array for use in a magnetic inductance tomography apparatus, in which driver/sensor coils are used to measure the induced flux in a conductive, dielectric and permittivity body, such as the human body. The sensor/driver coil array comprises at least one layer of thin coils whose centres are arranged on a regular grid, with adjacent coils overlapped by a suitable distance to cancel inductive neighbour coupling between them.

Abstract: An apparatus for detecting tampering with an integrated circuit (IC), the apparatus comprising a second circuit comprising at least one conductor for conducting electrical current, the electrical current comprising, during at least one period of time, current of known strength, the electrical current generating a magnetic field, at least one magnetic field sensing device operatively associated with the IC, the sensing device having at least one electrical characteristic responsive to changes in a sensed magnetic field, the magnetic field sensing device being positioned so as to sense the magnetic field generated by current in the at least one conductor, and an analyzer operatively associated with the at least one magnetic field sensing device and the IC, the analyzer determining that the IC is being tampered with based, at least in part, on changes in the at least one electrical characteristic of the at least one magnetic field sensing device in response to changes in the sensed magnetic field generated by th

Abstract: A magnetic field response sensor comprises an inductor placed at a fixed separation distance from a conductive surface to address the low RF transmissivity of conductive surfaces. The minimum distance for separation is determined by the sensor response. The inductor should be separated from the conductive surface so that the response amplitude exceeds noise level by a recommended 10 dB. An embodiment for closed cavity measurements comprises a capacitor internal to said cavity and an inductor mounted external to the cavity and at a fixed distance from the cavity's wall. An additional embodiment includes a closed cavity configuration wherein multiple sensors and corresponding antenna are positioned inside the cavity, with the antenna and inductors maintained at a fixed distance from the cavity's wall.

Abstract: An eddy current sensor for use as a dynamic proximity sensor, particularly for monitoring of blade tip timing and clearance in turbomachinery, has a common coil for use in both generating a magnetic field in a proximate region and detecting the effect of eddy currents generated by said field in electrically conductive objects passing through that region. The coil is wound on a rectangular or other elongate former so that the coil is itself elongate in section. This can improve the resolution of the device when used for sensing the passage of objects of elongate section (such as a turbine blade tip when the sensor coil is oriented with its shorter cross-sectional dimension aligned with the shorter cross-sectional dimension of the respective object. Also described is a method of processing a signal wave form from such devices to derive ‘trigger’ points for blade tip timing.

Abstract: Provided is a remote sensing apparatus comprising: (a) an electromagnetic field detector and (b) an acoustic resonator comprising an electromagnetic field generator and a sensing material in wireless communication with the generator; wherein the sensing material is in wireless communication with the detector, and an acoustic property of the sensing material is responsive to a change in state of an environment to which the sensing material is exposed, and wherein the sensing material is in the form of one or more particles and/or fragments.

Abstract: A non-contact plasma-monitoring apparatus and a non-contact plasma-monitoring method are provided. The non-contact plasma-monitoring apparatus is installed in a plasma processing apparatus including a processing chamber and a power supply unit and measures at least one of an electric field and a magnetic field, which are created around power supply wiring connecting the process chamber to the power supply unit, without physically contacting the power supply wiring.

Abstract: A method of detecting the presence of a substance (32) to be detected on a surface of a substrate (21), the method comprising: i) providing magnetic particles (35) to the substrate (21) for binding with the substance (32) to be detected; and ii) determining the presence of the substance (32) to be detected by detecting the magnetoresistive effect of the magnetic particles (35) bound to the substance (32) to be detected on a magnetoresistive element (40) positioned proximate the substrate surface.

Abstract: A system for monitoring a conveyor belt having magnetically permeable cords, has an AC magnetic field generator for generating an alternating magnetic field to magnetize the cords, in use; a magnetic field sensing unit for sensing the alternating magnetic field provided, in use, by the cords and for providing signals representative of the alternating magnetic field; arid a processor for processing the signals to monitor continuous parts of the cords. The system further has a DC magnetic field generator for erasing an AC field previously generated by the AC magnetic field generator, the AC magnetic field generator being positioned between the DC magnetic field generator and the magnetic field sensing unit. The processor also determines the speed of travel of the belt, and the position in space of a lateral edge of the belt.

Abstract: A metal detector transmitting, through a transmit coil, a repeating transmit signal cycle, which includes at least one receive period and at least one non-zero transmit coil reactive voltage period; and sensing a current in the transmit coil during at least one receive period to control a magnitude and/or duration of the at least one non-zero transmit coil reactive voltage period such that the average value of the current during at least one receive period of every repeating transmit signal cycle is substantially constant, and the current during at least one receive period is substantially independent of the inductance of the transmit coil.

Abstract: Disclosed is a method of analysis of a mixture of biological and/or chemical components that entails spatially arranging a chosen component attached to magnetic particles, exposing the particles to a magnetic field, and recording a magnetic induction signal, from which the content of the analyte in the mixture is judged; this includes grouping the chosen component in a probe volume, making the magnetic field alternating, pre-setting its spectrum, at least, at two frequencies, and recording the signal at a frequency, which is a linear combination of these frequencies, during the exposure of the magnetic particles to the field.

Abstract: It is an object of the present invention to provide an eddy current testing method capable of securely detecting a high hardness part locally occurring in a metal material having magnetism, and capable of securely checking whether the high hardness part has been removed after execution of a repairing treatment for removing the high hardness part. In the eddy current testing method according to the present invention, a frequency of the AC current for energizing the differential coil 1 is set so that a phase difference between a magnetism variation signal of the metal material P and a liftoff signal detected by the differential coil is equal to or larger than 135°, and a local high hardness part occurring in the metal material is detected based on an amplitude and a phase of a detection signal outputted from the differential coil.

Abstract: Methods and processes for determining the particle size distribution of metal catalysts are provides. Superconducting Quantum Interference Device (SQUID) magnetometer is used to evaluate the magnetic catalyst particle sizes dispersed in the support material. Dependence on variation of the metal/support material ratio, which defines the metal particle sizes, the catalyst can show paramagnetic, superparamagnetic, and ferromagnetic behaviors.

Abstract: An endurance testing system is configured to test endurance of a first detecting apparatus. The endurance testing system includes a second detecting apparatus, a movement module, a processor, and a storage module. The movement module includes a first inductive object and a second inductive object. The processor is connected to the first and second detecting apparatuses, and the movement module, for controlling the movement module and counting a first number of times the first detecting apparatus detects the first inductive object, and a second number of times the second detecting apparatus detects the second inductive object. The storage module is connected to the processor, for storing the first and second numbers of times from the processor. The first detecting apparatus fails the testing upon the condition that the first number of times is not equal to the second number of times.

Abstract: A metal detector transmitting high current pulses and employing the high voltage back EMF signals which occur at their termination. The method employed uses a resonant tuned receive coil which provides a major improvement in the depth of detection of metallic objects and interference rejection over current time and frequency domain metal detectors.

Abstract: A system for measuring the concentration of magnetic ballast in a moving slurry including a detection conduit surrounded by a set of coaxial detection coils configured to receive the moving slurry, a reference conduit surrounded by a set of coaxial coils, an AC power source for establishing a magnetic field in one of the detection coils and one of the reference coils, and a measurement subsystem for measuring the differential induced voltage between one of the set of coaxial detection coils and one of the set of coaxial reference coils to determine the concentration of the magnetic ballast in the moving slurry.

Abstract: The present invention has the object of providing a charged particle beam irradiation method ideal for reducing the focus offset, magnification fluctuation and measurement length error in charged particle beam devices. To achieve these objects, a method is disclosed in the invention for measuring the electrical potential distribution on the sample with a static electrometer while loaded by a loader mechanism. Another method is disclosed for measuring the local electrical charge at specified points on the sample, and isolating and measuring the wide area electrostatic charge quantity from those local electrostatic charges.

Abstract: A pulse-induction type metal detector that reliably identifies ferrous and non-ferrous targets in soils with varying mineral content. The influence of the background signals from the soil is removed continuously, without the need for manual adjustment of controls by the operator, when the soil mineralization changes. The background signals are removed without affecting the sensitivity of the detector to metallic targets and the background signal removal process does not make the detector insensitive to targets whose time constant coincides with that of the soil.

Abstract: Any inspection object regardless of material can easily be inspected or discriminated with high accuracy and high sensitivity by being placed in a magnetic field generated by applying an alternating current to an exciting coil and detecting changes of voltage level and phase of electromotive force induced by a detection coil unit. The discrimination of the inspection object is performed on the basis of a DC voltage value with respect to a standard specimen and a phase differential voltage value with respect to a phase difference between the phase of a voltage signal from the induction coil and the phase of the exciting current to the exciting coil.

Abstract: A system for determining magnetic permeability of a material. Two electrical inductors formed as primary and secondary concentric coils share a common magnetic core space. A first AC voltage applied to the primary coil creates a magnetic flux in the core proportional to the magnetic permeability of the material. The magnetic flux induces an AC voltage in the secondary coil indicative of the apparent magnetic permeability of the sample. The apparent permeability is corrected for conductivity by imposing a second AC voltage and resistor in series across first and second electrodes disposed in the material. When the material is a magnetorheological fluid, the magnetic permeability is proportional to the concentration of magnetic particles in the sample and can be back-calculated from the amplitude of the secondary voltage signal.

Abstract: The invention relates to a probe for electrical measurements and use of a flexible probe to produce an inflexible probe. Conventional probes comprise a substrate which is mechanically rigid. As a result only planar surfaces may be examined with the probe. According to the invention, a probe is flexibly embodied by means of a flexible substrate such that the probe may be adjusted to match various curvature radii of test bodies.

Abstract: An arrangement and a method for influencing and/or detecting magnetic particles in a region of action is disclosed, which arrangement comprises:—selection means for generating a magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action,—drive means for changing the position in space of the two sub-zones in the region of action by means of a magnetic drive field so that the magnetization of the magnetic particles changes locally,—receiving means for acquiring signals, which signals depend on the magnetization in the region of action, which magnetization is influenced by the change in the position in space of the first and second sub-zone, wherein the selection means and/or the drive means and/or the receiving means comprises at least partially a litz wire/stranded wire.