Abstract: A method of producing a magnetic field sensor, whose sensor element is formed by at least one piece of wire comprising amorphous or nanocrystalline ferromagnetic material, whose electrical impedance is dependent on the magnetic field. The piece of wire is connected by an electrical terminal of nonferromagnetic metal. The ends of the at least one piece of wire are press-fitted into two spaced-apart conductors of nonferromagnetic metal, in particular copper.

Abstract: A magnetoresistance effect element according to the present invention comprises magnetic multilayer film having a non-magnetic metal layer, a ferromagnetic layer formed on one surface of the non-magnetic metal layer, a soft magnetic layer formed on the other surface of the non-magnetic metal layer, and a pinning layer which is formed on the ferromagnetic layer to pin a direction of magnetization of the ferromagnetic layer, wherein the ferromagnetic layer and the pinning layer are coupled to each other with epitaxial growth.Accordingly, the magnetoresistance device using the magnetoresistance effect element as described above exhibits an extremely large MR ratio and a linear rise-up characteristic of MR change in an extremely small range of applied magnetic field of about -10 to 10 Oe, and has high sensitivity to magnetic field, a large MR slope under a high-frequency magnetic field and an excellent heat resistance.

Abstract: A magnetic sensor (31) includes an insulator substrate (37) having first and second surfaces opposite to each other, a soft magnetic element having first and second ends opposite to each other and mounted on the first surface of the insulator substrate, and a conductor mounted on the second surface of the insulator substrate, and an output port coupled to the first and the second ends of the soft magnetic element for deriving an impedance of the soft magnetic element between the first and the second ends. The impedance changes in dependence upon a magnetic field strength applied to the soft magnetic element. In the magnetic sensor (31), the soft magnetic element is a soft magnetic wire (33). The conductor is a ground conductor (35) to be grounded. The magnetic sensor may further comprise a short-circuiting conductor (39) connecting the first end of the soft magnetic wire with the ground conductor while the output port is coupled to the short-circuiting conductor and the second end of the soft magnetic wire.

Abstract: A magnetism detecting device of a magnetic impedance effect type includes a high-permeability magnetic film formed on a side of an approximately rectangular parallelepipedic, non-magnetic substrate. The high-permeability magnetic film is formed as a folded pattern having end portions extending in opposite directions and at least one folded portion disposed between the end portions, a longitudinal direction of the high-permeability magnetic film being parallel to a magnetic-field detecting direction. The high-permeability magnetic film is imparted magnetic anisotropy so that a direction of an axis of easy magnification of the high-permeability film is perpendicular to the longitudinal direction of the high-permeability magnetic film in a film plane thereof. Conductive films are formed at both ends of the high-permeability magnetic film as terminals.

Abstract: A magnetic sensor includes a DC power source, a multivibrator circuit composed of two CMOS inverters, a resistor, and a capacitor, each of the CMOS inverters being composed of a pMOS transistor and an nMOS transistor connected in series, and a magneto-impedance element. In a transition state attributable to switching operations of the CMOS inverters, a sharp pulse current is caused to flow through the magneto-impedance element so as to excite the magneto-impedance element sufficiently causing the skin effect, whereas in a steady state, the flow of the current is stopped by the CMOS inverters so as to reduce power consumption.

Abstract: A method of manufacturing a magnetic field sensor having a stacked structure of:an exchange-biasing layer (2) comprising nickel oxide on a substrate (1) anda magnetic layer (3) which is exchange-biased with the exchange-biasing layer (2),whereby at least the exchange-biasing layer (2) is provided by sputter deposition using a sputter gas which comprises Ne and/or He. The magnetic layer (3) preferably comprises permalloy. In a particular embodiment, the magnetic layer (3) is separated from a second magnetic layer (5) by an interposed non-magnetic layer (4), so as to form a spin-valve trilayer.

Abstract: In a magnetic detecting element utilizing a magnetic impedance effect, a high-permeability magnetic film is formed on a non-magnetic substrate and has magnetic anisotropy in a predetermined direction in the plane of the magnetic film. A high-frequency current is applied across two points in a direction perpendicular to the direction of the magnetic anisotropy, and a change in impedance generated between the two points is converted into an electric signal to obtain an output.

Abstract: A magnetic sensor element 1 includes a substrate 10, a conductive layer 12 of a conductive material, and a magnetic layer 11 of a magnetic material, which encloses the conductive layer 12. AC is applied to the element from a drive power source 50, and a detector 60 detects an impedance change due to an external magnetic field. The magnetic layer 11 is bestowed with magnetic anisotropy in a direction orthogonal to the direction of energization of the element 1. With the provision of the conductive layer 12 of conductive material and also with magnetic anisotropy imparted to the magnetic layer 1, the element 1 may be made a low resistivity element. A reactance change and a resistance change of the element due to an external magnetic field change, thus can be effectively detected in drive frequencies two orders of magnitude lower than in the case of a prior art magnetic sensor element.

Abstract: A magnetic field sensor for gradient field detection (gradient type magnetic field sensor) cancels relatively uniform disturbance magnetic fields (background magnetic fields) such as the terrestrial field through the use of two magneto-impedance elements, thereby making it possible to detect only a signal magnetic field (gradient field) which is considerably localized spatially. The magnetic field sensor includes a pair of sensor heads made of an amorphous wire, and a self-oscillation type electronic circuit for detecting a spatially uniform magnetic field or a differential value of a spatially gradient magnetic field by switching the direction of a bias magnetic field applied to the pair of sensor heads.

Abstract: An alternating bias current is made to flow through a coil wound around an MI device incorporated in an oscillation circuit, and an alternating-current bias magnetic field is applied to the MI device. An amplitude-modulated waveform corresponding to peaks which alternate between two different heights is provided at the output of the oscillation circuit in accordance with an impedance variation in the MI device according to an external magnetic field and the alternating-current bias magnetic field. The difference in height between the peaks corresponds to the strength of the external magnetic field. The output of the oscillation circuit is envelope-detected by an envelope detecting circuit, and an alternating-current component from which a direct-current component is eliminated is inputted to a comparator. The comparator provides an output signal having a digital waveform pulse-width modulated according to the difference in height between the peaks.

Abstract: A double tunnel junction is disclosed that can be used as a magnetic sensor or as random access memories. The preferred embodiment comprises three magnetic metal materials separated by two insulating layers. A current is passed through the first tunnel junction thereby developing a voltage in the second junction. The resistance of this device can be changed over a 100% when an external magnetic field of just a few gauss is applied.

Abstract: A new hybrid magnetic spin injected-FET structure can be used as a memory element for the nonvolatile storage of digital information, as well as in other environments, including for example logic applications for performing digital combinational tasks, or a magnetic field sensor. The hybrid FET uses ferromagnetic materials for the source and drain, and like a conventional FET, has two operating states determined by a gate voltage, "off" and "on". The ferromagnetic layers of the hybrid FET are fabricated to permit the device to have two stable magnetization states, parallel and antiparallel. In the "on" state the spin injected FET has two settable, stable resistance states determined by the relative orientation of the magnetizations of the ferromagnetic source and drain.

Abstract: A new magnetic spin transistor is provided. This spin transistor can be used as a memory element or logic gate, such as an OR, AND, NOT, NOR and NAND gate. The state of the magnetic spin transistor logic gate is set inductively. This new magnetic spin transistor/gate can be operated with current gain. Furthermore, inductive coupling permits the linking of multiple spin transistors and spin transistor gates to perform combinational tasks. A half adder embodiment is specifically described, and other logic gates and combinations of half adders can be constructed to perform arithmetic functions as part of a microprocessor.

Abstract: A method of manufacturing a magnetoresistance element that can accurately sort out truely defective products from apparently defective products due to the manufacturing processes. Manufacturing processes for MR elements includes a MR element formation process, a magnetic field application process and an electric inspection process. In the magnetic field process, the magnetic field application is limited to a range within 75.degree. to the longitudinal direction of a MR element pattern. By performing the magnetic field application process before the electric inspection process, the anisotropic magnetic field due to a shape magnetic anisotropy of the MR element can be aligned almost in a fixed direction, defective products due to the manufacturing processes can exactly be sorted out from the apparently defective products in the electric inspection process, so that the yield rate can be improved.

Abstract: A device for detecting a magnetic field, which device comprises a magneto-resistive multilayer structure comprising a first magnetic layer (1) which is separated from a second magnetic layer by an interposed non-magnetic layer, the multilayer structure having a first in-plane reference axis (R.sub.1) coinciding with the direction in which magnetic flux is offered to the multilayer structure during operation, and a second in-plane reference axis (R.sub.2) which is perpendicular to the first reference axis (R.sub.1), whereby the magnetic easy axis (E.sub.1) of the first magnetic layer (1) is canted through an acute in-plane angle .alpha. with respect to the second reference axis (R.sub.2), and the magnetic easy axis (E.sub.2) of the second magnetic layer is canted in the opposite sense through an acute in-plane angle .beta. with respect to the second reference axis (R.sub.2).

Abstract: A magnetic field sensor having a planar element made of a material formed by crystalline magnetoresistive thin layers with an anisotropy of resistivity in the planar element also having, in the planar element, two magnetization axes of different values. This sensor also has two electrical connections enabling, in the presence of an external magnetic field, the flow of a current in the element in a first direction that is not collinear with each of the axes of magnetization and two electrical connections enabling a measurement of voltage in a second direction transversal to the first direction. This sensor thus works by planar Hall effect.

Abstract: An eddy current surface inspection array probe and method for detecting cracks and flaws in aircraft skin metal immediately surrounding rivets, without requiring rivet removal or manual scanning. The array probe includes a circular array of small sense coils positioned beneath a much larger drive coil encased in ferrite. The sense coils are differentially connected in pairs such that the signals from two sense coils located on opposite sides of the rivet (180.degree. apart) subtract to produce a resultant output signal. During operation, the probe is positioned concentrically over the rivet and data acquired from all sense coil pairs. If no cracks or other defects are present, all sense coil pairs produce a null (zero) signal. If a crack exists, some sense coil pairs (the exact number depending on the crack length, number of sense coils, and sense coil spacing) produce a non-zero signal.

Abstract: A first magnetically coupled film sensing element and a second magnetically coupled film sensing element are arranged to change resistance in response to a magnetic filed when biased by a current through the elements. A current carrying conductor spaced from the elements sets the magnetization in the elements. A transfer function of the elements is adjusted by varying the current through the elements or the current through the conductor.

Abstract: There is provided an apparatus for measuring magnetic sources that exist in an object and produce magnetic fields outside the object. The apparatus comprises an element for detecting the magnetic fields which has a sensing portion placed in proximity with the object and adapted to incorporate an observing plane. The observing plane consists of a plurality of sensing blocks each containing at least three sensing planes on which a magnetic sensor is each mounted. The normal directions of the sensing planes are different from each other. The apparatus further comprises an element for evaluating three-dimensionally the intensities of other magnetic fields at given evaluation positions on the basis of values of the magnetic fields at the detecting element, and an element for obtaining data of the magnetic sources on the basis of the intensities of the other magnetic fields evaluated by the evaluation element.

Abstract: A detector for detecting an oriented physical variable includes, in a casing, an acceleration chip-shaped sensor and a board bearing electronic components. The sensor is mounted on a first surface of an insulating part that includes a second surface fastened to the casing, and a third surface that extends parallel with the plane of the board. Conductive paths extend from the first surface, where they are connected to the sensor, and overlap the third surface, where they are connected to contacts of the board. The sensor can be oriented in a desired direction, with respect to the plane of the board. The various electric connections can be formed by ultrasonic bonding.

Abstract: A magnetic spin transistor, usable as a memory cell, magnetic pick-up head, or a current switch, that includes a trilayer planar structure of a conductive, nonferromagnetic layer (16) sandwiched between two ferromagnetic layers (12, 14) of different coercivities. A biasing current pumped between one of the ferromagnetic layers and the nonferromagnetic layers produces a voltage on the other ferromagnetic layer. The polarity of the voltage depends on the relative magnetic polarization of the two ferromagnetic layers. As a memory cell, current passing through adjacent lines magnetize the ferromagnetic layer of lower coercivity. As a magnetic pick-up head, an adjacent magnetic recording track supplies the magnetic field sufficient to switch the lower-coercivity ferromagnetic layer.

Abstract: A magnetoencephalograph comprising an oxide superconductor magnetic shielded vessel and a cryostat for cooling the magnetic shielded vessel, a multichannel SQUID and a cryostat for cooling the SQUID inserted together in the magnetic shielded vessel from one end of the magnetic shielded vessel, a magnetic-field detection unit situated in the vessel for detecting magnetic fields, and a coupling portion for coupling the SQUID and the magnetic-field detection unit with respect to the signals, and the SQUID and the magnetic-field detection unit being detachable. The magnetoencephalograph makes possible the detection of the very weak magnetic fields from the human brain and therewith reduction of the diameter of the opening of the magnetic shield vessel for inserting the SQUID. The reduction of the diameter of the SQUID opening in turn makes it possible to reduce the length of the magnetic shielded vessel, thereby preserving a high shielding effect of the magnetic shield vessel because of the L/D relationship.

Abstract: A device is disclosed for measuring low-flux magnetic fields with a sensor operating according to the core saturation principle. The sensor is provided with a ferromagnetic core, an excitation coil and a measuring coil. The measuring coil, the excitation coil and the ferromagnetic core are electrically insulated from one another, each being disposed in a single, separate, parallel layer on a support material.

Abstract: A magnetoresistive sensor includes a magnetic field detecting portion composed of a ferromagnetic thin film formed on one side of an insulating rectangular substrate, at least two terminal electrode portions and wiring portions. In the magnetoresistive sensor, the surface level of at least two corner portions is lower than that of the surface portion of the substrate other than at least two corner portions on the one side of the substrate, the at least two terminal electrode portions are separately formed at the corner portions having the lower surface level and the magnetic field detecting portion composed of the ferromagnetic thin film is formed on a portion of the surface of the substrate other than the at least two corner portions.

Abstract: A magnetometer is prepared by depositing three thin-film SQUID magnetic field detectors upon a substrate. Two of the detectors incorporate stripline SQUID detectors deposited at right angles to each other, to measure the orthogonal components of a magnetic field that lie in the plane of the substrate. The third detector uses a planar loop SQUID detector that measures the component of the magnetic field that is perpendicular to the substrate. The stripline SQUID detectors have thin-film base and counter electrodes separated by an insulating layer which is at least about 1 micrometer thick, and a pair of Josephson junctions extending between the electrodes through the insulating layer.

Abstract: A magnetic-field-sensitive device includes several magnetic-field sensors. Each sensor comprises a compound element surrounded by a coil winding. Each compound element is made of two ferromagnetic cell components extending in one axial direction with uniaxial magnetic anisotropy and with different coercive field strengths. A spontaneous reversal of magnetization is produced by an external magnetic switching field only in the cell component having the lower coercive field strength. The magnetic-field sensors are combined to form a series arrangement, or array, and the coil windings and cell components of the magnetic-field sensors of the array are formed as thin-film structures on a non-magnetic substrate.

Abstract: A thin film vector magnetometer is configured to produce an output that ves linearly with the component of an externally applied magnetic field in the plane of a thin film chip portion thereof along a predefined sensitivity axis. The sensitivity and linear dynamic range of the thin film vector magnetometer are intimately related to each other through a bias field supplied by a bias magnet portion of the device. The bias field also defines the sensitivity axes of the magnetometer which is orthogonal to the unidirectional bias field supplied by the bias magnet.

Abstract: A device for measuring a weak magnetic field is disclosed. The device includes a substrate, a magnetic core having a high magnetic permeability and in the form of a surface film on a substrate, and at least two coils magnetically coupled to the magnetic core. A pulse generator is connected to one of the coils and is used to drive the magnetic core into intermittent saturation. The other coil is used to generate an output signal. The device can be used for measuring the weak magnetic fields associated with bank notes for identifying the values of the bank notes.

Abstract: A device for measuring a weak magnetic field is disclosed. The device includes a substrate, a magnetic core having a high magnetic permeability and in the form of a surface film on a substrate, and at least two coils magnetically coupled to the magnetic core. A pulse generator is connected to one of the coils and is used to drive the magnetic core into intermittent saturation. The other coil is used to generate an output signal. The device can be used for measuring the weak magnetic fields associated with bank notes for identifying the values of the bank notes.

Abstract: A current sensor having an element made of amorphous magnetic metal is disclosed herein. The current sensor includes an element located near a conductor and made of amorphous magnetic metal whose magnetic property varies in accordance with the intensity of a magnetic field generated from a current flowing through the conductor, magnet applying a DC-bias magnetic field to the element, a coil exhibiting electrical property corresponding to the magnetic property of the element, and output device for outputting a signal corresponding to the electrical property of the coil. The coil has a specific positional relationship with the element, such that at least part of the magnetic flux generated by the coil passes through the element.

Abstract: A thin film vector magnetometer is configured to produce an output that varies linearly with the component of an externally applied magnetic field in the plane of a thin film chip portion thereof along a predefined sensitivity axis. The sensitivity and linear dynamic range of the thin film vector magnetometer are intimately related to each other through a bias field supplied by a bias magnet portion of the device. The bias field also defines the sensitivity axis of the magnetometer which is orthogonal to the unidirectional bias field applied by the bias magnet.

Abstract: A device for measuring a weak magnetic field is disclosed. The device includes a substrate, a magnetic core having a high magnetic permeability and in the form of a surface film on a substrate, and at least two coils magnetically coupled to the magnetic core. A pulse generator is connected to one of the coils and is used to drive the magnetic core into intermittent saturation. The other coil is used to generate an output signal. The device can be used for measuring the weak magnetic fields associated with bank notes for identifying the values of the bank notes.

Abstract: An integrated-circuit one-way isolation-coupler for a controlling electrical circuit and a controlled electrical circuit and improvements in carrier-domain magnetometers and other applications thereof. In the isolator a magnetic-field source, such as a flat coil, produces a magnetic field from current applied from the controlling circuit, while a detector such as a carrier-domain-magnetometer detects the magnetic field so produced and produces a signal therefrom. A dielectric medium, such as silicon dioxide or silicon nitride separates the source from the detector. The source, the detector, and the dielectric medium, are all incorporated on a single IC chip, such as silicon, or gallium arsenide, or semiconductor material. An amplifier may also be incorporated and may deliver the amplified signal to the controlled circuit. Preferably there are two carrier-domain-magnetometers located so that they are symmetrical with respect to the flat coil.

Abstract: Gradient meter to measure the spatial derivatives.DELTA.Hi/.DELTA.j (i=x, y, z ; j=x, y, z)of a magnetic field.This gradient meter comprises two magnetic sonds (7a, 7b) with thin layer, of which the geometric axes of the counterreaction windings are aligned in the direction of axis i, said sonds being spaced from each other along the axis j, the counterreaction current of the first sond being injected in the second sond, the counterreaction current of said second sond being then representative of the value.DELTA.Hi/.DELTA.jto be measured.

Abstract: A magnetometer made of thin film ferromagnetic material measures a component of an extraneous magnetic field which lies within the film at right angles to the direction of a magnetic field which is periodically excited within the film in opposite directions at sufficient intensity to saturate the film, in the presence of unidirectionally flowing current within the film along a path preferably extending at an angle of about 45.degree. to the axis of anisotropy lying within the film.

Abstract: A detector head for use in a measuring device includes a plurality of constituent measuring elements arranged in at least two blocks, each block producing an output signal of equal amplitude, and a phase shifter provided to shift the relative phases of the output signals of the blocks to have a predetermined relative phase difference, whereby selected higher-order harmonic components are cancelled from the resultant signal formed by summing the signals produced by the separate blocks of constituent elements.

Abstract: A measuring transformer comprises a measuring conductor carrying the current I.sub.m to be measured, a pre-magnetizing winding which carries a pre-magnetizing current I.sub.v, and a magnetic field comparing means which is exposed to the magnetic field produced by the current I.sub.m and the magnetic field produced by the pre-magnetizing current I.sub.v and is alternately controlled in both directions of saturation. The magnetic field comparing means is a magnetic film which may be anisotropic, operated in the magnetic preferential direction, and have a thickness of at most a few microns. It may be secured to pole shoes of a magnetic core or arranged between a flat measuring conductor and a pre-magnetizing coil of flat cross-section. The measuring transformer can be used as an input transformer in a static electricity meter. In a further embodiment, the output pulses can be obtained directly from the magnetic field comparing means.

Abstract: A current-measurement transducer comprises a thin-film magnetic coil for passing an alternating premagnetizing current, generating an alternating premagnetizing field, and a magnetic-field comparator which includes first and second magnetic anisotropic films disposed in respective substantially parallel planes. Each film is composed of ferromagnetic and magnetoresistive material, and defines a magnetic easy axis, along which the film is relatively easily magnetizable, and a magnetic hard axis, at right angles to the easy axis, along which the film is harder to magnetize than along the easy magnetic axis. A non-magnetic and electrically at least poorly conducting layer separates the films, and the films are coupled to one another sufficiently tightly so that a current passing in one magnetic film generates an auxiliary magnetic field along the hard magnetic axis of the other magnetic film.

Abstract: A transducer for measuring a current, includes a magnetic core which has a gap substantially impeding passage of any magnetic flux, a coil arranged to pass a premagnetizing current for producing a first magnetic field, a loop for carrying the current to be measured, so as to produce a second magnetic field, and a magnetic field comparision device exposed to the magnetic fields. The magnetic field comparison device includes a magnetic film bridging the flux gap. The film is alternately controllable in respective opposite directions of saturation substantially by the first magnetic field, and evaluates the measuring current in dependence of the magnetic fields. The magnetic core, the coil, the loop, and the magnetic film are substantially disposed concentrically.

Abstract: A unidirectional magnetometer comprising at least two magnetostatic wave oscillators with resonators or delay lines, made in two portions in a magnetic material layer respectively subject to the field to be measured and to given magnetic fields of the same direction, but of opposite sense and adjacent intensities.

Abstract: A measuring transformer comprises a measuring conductor carrying the current I.sub.m to be measured, a pre-magnetizing winding which carries a pre-magnetizing current I.sub.v, and a magnetic field comparing means which is exposed to the magnetic field produced by the current I.sub.m and the magnetic field produced by the pre-magnetizing current I.sub.v and is alternately controlled in both directions of saturation. The magnetic field comparing means is a magnetic film which may be anisotropic, operated in the magnetic preferential direction, and have a thickness of at most a few microns. It may be secured to pole shoes of a magnetic core or arranged between a flat measuring conductor and a pre-magnetizing coil of flat cross-section. The measuring transformer can be used as an input transformer in a static electricity meter. In a further embodiment, the output pulses can be obtained directly from the magnetic field comparing means.

Abstract: A thin-layer magnetic field sensor in which a thin magnetic layer which is magnetized in a preferred direction is surrounded by a magnetic HF measuring coil with variable inductance and in which an external magnetic field and the coil axis are aligned so as to be parallel to one of the preferred directions. The sensor comprises a sequence of geometrically structured layers arranged on a substrate, i.e. a structurized metal electrically conducting layer, a dielectric layer, a magnetic layer magnetized in a preferred direction, a further dielectric layer and a further structurized metal electrically conducting layer which forms with the first electrically conducting layer a coil which surrounds the magnetic layer.

Abstract: A flux-sensitive magnetic head employs, at its back part, a structure having a thin single domain magnetic film coated thereon. A coil wraps around the coated structure, and a direct current is passed through the coil, thereby to apply a hard axis magnetic bias to the film. Signal flux appearing at the head front gap asserts a magnetic force along the hard axis of the film. Contrary to what would be expected, the signal flux causes the inductance of the coil to vary. Such inductance variation may be conveniently detected by (1) connecting the variable inductor into a tank circuit, (2) applying a high frequency ac ripple to the "hard axis" dc bias, and (3) measuring the "hard axis" detuning experienced by the tank circuit.

Abstract: A sensor-recorder for recording a representation of the direction and peak amplitude of a transient current. A magnetic thin film is coated on a glass substrate under the influence of a magnetic field so that the finished film is magnetically uniaxial and anisotropic. The film is split into two oppositely magnetized contiguous domains with a central boundary by subjecting adjacent portions of the film simultaneously to magnetic fields that are opposed 180.degree.. With the split-domain sensor-recorder placed with the film plane and domain boundary either perpendicular or parallel to the expected conductive path of a transient current, the occurrence of the transient causes switching of a portion of one domain to the direction of the other domain. The amount of the switched domain portion is indicative of the amplitude of the peak current of the transient, while the particular domain that is switched is indicative of the direction of the current.

Abstract: A thin film magnetometer is disclosed, adapted to detect changes in the eh's magnetic field, but which is insensitive to apparent changes in the field as result from spin of the magnetometer relative to the field. Insensitivity to spin is obtained by forming the thin film sensor as a loop having a plane of symmetry in which the axis of spin lies.

Abstract: A flux sensitive magnetic head is disclosed wherein a thin single domain magnetic film coated on a non-conductor bridges the head gap. A magnetic bias is applied to the hard axis of the film; and flux entering the gap causes the resistivity of the film to vary about a resistance reference established by the bias. The resistance variation is converted to a useful signal corresponding to the flux entering the gap.

Abstract: The magnetometer transducer includes a group of plated magnetic wires arranged in parallel physically and connected in series electrically to serve as a drive circuit, and several turns of 0.025 mm diameter wire wound around the group of plated magnetic wires to serve as a sense coil. Each of the magnetic wires has a diameter of 0.05 mm with their centers being 0.25 mm apart. Because of its shape and small size, it is capable of very good spatial resolution of magnetic fields as low as 0.02 oe and it can make measurements of transverse magnetic fields as close as 0.08 mm from a surface. The magnetometer utilizes two X-Y recorders in a unique transducer scanning technique. One of the recorders moves the transducer over the specimen being measured and the other recorder records the measurements.

Abstract: A measuring transformer comprises a measuring conductor carrying the current I.sub.m to be measured, a pre-magnetizing winding which carries a pre-magnetizing current I.sub.v, and a magnetic field comparing means which is exposed to the magnetic field produced by the current I.sub.m and the magnetic field produced by the pre-magnetizing current I.sub.v and is alternately controlled in both directions of saturation. The magnetic field comparing means is a magnetic film which may be anisotropic, operated in the magnetic preferential direction, and have a thickness of at most a few microns. It may be secured to pole shoes of a magnetic core or arranged between a flat measuring conductor and a pre-magnetizing coil of flat cross-section. The measuring transformer can be used as an input transformer in a static electricity meter. In a further embodiment, the output pulses can be obtained directly from the magnetic field comparing means.

Abstract: The present invention is an apparatus and method for the non-destructive ting of the anisotropic magnetoresistance parameters of a film. A plurality of contacts points are securely disposed in a generally planar support means and engagable with a surface of the film for measuring the anisotropic magnetoresistance parameters of the film in accord with a predetermined equation.