2398 results about "Magnetic shield" patented technology

A method and system provide a magnetic transducer including first and second shields, a read sensor, and magnetic bias structure(s) adjacent to the read sensor. The read sensor and magnetic bias structure(s) are between the shields. The second shield includes first and second ferromagnetic layers, a nonmagnetic spacer layer and a pinning layer. The nonmagnetic spacer layer is between the first and second ferromagnetic layers. The first ferromagnetic layer is between the read sensor and the nonmagnetic spacer layer. The pinning layer is adjacent to the second ferromagnetic layer. The first and second ferromagnetic layers are coupled antiparallel. The first ferromagnetic layer includes magnetic layers interleaved with trilayer(s). Each magnetic layer includes crystalline grains. The trilayer(s) include an amorphous nonmagnetic layer less than three Angstroms thick. Thus, the magnetic layers are ferromagnetically coupled but the crystalline grains in different magnetic layers are decoupled.

A selectively controllable electromagnetic shield having an electromagnetic shielding material and a mechanism for selectively generating an aperture in the shield. The mechanism for selectively generating an aperture may be a magnetic field source that generates a magnetic field of sufficient strength to substantially saturate all or a portion of the shielding material. For example, a permanent magnet or DC electromagnet may be used to selectively saturate the shield. In its un-saturated state, the magnetic shield has a high permeability and functions as a flux path for the magnetic field. Once saturated, the permeability of the shield is substantially reduced so that the magnetic field lines are no longer drawn into the shield to the same degree. As a result, once saturated, a substantially greater amount of the electromagnetic field may flow through or around the shield in the saturated region.

A method and system provide a magnetic transducer including a first shield, a read sensor, and a second shield. The read sensor is between the first shield and the second shield. The second shield includes a first ferromagnetic layer, a nonmagnetic spacer layer, a second ferromagnetic layer and a pinning layer. The nonmagnetic spacer layer is between the first ferromagnetic layer and the second ferromagnetic layer. The first ferromagnetic layer is between the read sensor and the nonmagnetic spacer layer. The pinning layer is adjacent to the second ferromagnetic layer. The first ferromagnetic layer is coupled antiparallel with the second ferromagnetic layer. At least one of the first ferromagnetic layer and the second ferromagnetic layer includes a CoFe portion adjacent to the nonmagnetic spacer layer. The CoFe portion includes at least twenty-five atomic percent and not more than fifty atomic percent Fe.

A water-repelling layer is formed on a resin film, and a stripe pattern region is formed so as to be positioned within a surface region of the water-repelling layer and so as to be relatively hydrophilic with respect to water repellency of the water-repelling layer. A magnetic stripe pattern is formed of needle-shaped magnetic grains oriented and aggregated in the stripe pattern region. The needle-shaped magnetic grains are arranged in a desirable state in a predetermined stripe pattern, with a high magnetic permeability and a magnetic sheet with stripe-arranged magnetic grains that is thin and flexible is obtained.

Improved electromagnetic compatibility for integrated motherboard or device board designs is provided by magnetic shielding, electric shielding, or both integrated into the chip packaging materials. Motherboard emissions may be reduced by use of the shielding. A nonconductive primary and tertiary layer sandwich a high-conductivity metal secondary layer forming a Faraday cage for electric field shielding. A nonconductive primary layer is covered by a tertiary layer formed of a composite having permeable material for magnetic shielding. The tertiary layer formed of a composite could include a high permeability particulate ferrous material. Both the secondary layer and the tertiary layer formed of a composite could be used for both electric and magnetic shielding of chips.

A shielded substrate assembly that contains a magnetic shield with a layer of magnetic shielding material; the magnetic shield has a magnetic shielding factor of at least about 0.5. The magnetic shield contains nanomagnetic material nanomagnetic material with a mass density of at least about 0.01 grams per cubic centimeter, a saturation magnetization of from about 1 to about 36,000 Gauss, a coercive force of from about 0.01 to about 5,000 Oersteds, a relative magnetic permeability of from about 1 to about 500,000, and an average particle size of less than about 100 nanometers. The nanomagnetic material contains magnetic material with a coherence length of from about 0.1 to about 100 nanometers.

An implantable device that contains a power source, a device for producing electrical signals, and a conductor assembly for communicating the electrical signals to biological matter. The conductor assembly contains of a conductor that is capable of being flexed at least about 15 degrees and that has a resistivity at 20 degrees Centigrade of from about 1 to about 100 micro ohm-centimeters. The conductor assembly also contains a magnetic shield located above the flexible conductor; the magnetic shield contains an antithrombogenic composition. The magnetic shield also contains a magnetic shielding material that has a magnetic shielding factor of at least about 0.5.

A current sensor assembly includes a sensor coil, an electrostatic shield coil, a core, a housing, and a magnetic shield. The sensing coil, electrostatic shield coil, core, housing, and magnetic shield can be of toroidal symmetry and arranged coaxially about a pair of primary current conductors. The conductors can be either asymmetric or symmetric with respect to the geometric center of the remaining sensor assembly. The core and a secondary winding make up a current sensor. The core is cylindrically shaped and fabricated of non-magnetic material. The secondary winding is wound over the cylindrical core to form a toroidally shaped winding. When assembled into the current sensor assembly, the core and windings are disposed around two single turn primary windings through which AC currents to be measured flow. Alternatively, the conductor can be flat and the sensor can be a solid state sensor that includes an electrostatic shield. The conductor can have a magnetic flux concentrator positioned about the conductor in the same region where the sensor is located.

There is provided a PET-MRI hybrid apparatus and method for integrating a PET image and an MRI image so that anatomical, hemodynamical and molecular information on human tissues are simultaneously presented in a single image. The PET-MRI hybrid system comprises a first scanner for obtaining anatomical and hemodynamical information, and a second scanner for obtaining molecular and functional information on the human tissues. Along a path between the first scanner and the second scanner, a transferring railway system which includes runs, and a movable bed for supporting a subject installed on the railway. The PET-MRI hybrid system also comprises a “RF+ magnetic” shield and a “magnetic” shield between path between the first scanner and the second scanner, which switch between an open status and a close status in a completely synchronized manner to assure a complete magnetic shield for the PET system at any given time. The subject is fastened on the bed and transferred along the railway between the first and second scanner to provide accurately fused MRI and PET images.

A structure for magnetically shielded transmission lines for use with high speed integrated circuits having an improved signal to noise ratio, and a method for forming the same are disclosed. At least one magnetic shield structure contains electrically induced magnetic fields generated around a number of transmission lines. The shield material is made of alternating layers of magnetic material and insulating material.

A dimmable electrodeless light source includes an electrodeless lamp, an electronic ballast and a dimming module. The light source further includes coupling transformers coupled to the electrodeless lamp for inductively coupling power to the lamp to generate light. An auxiliary winding electromagnetically coupled to the primary winding of at least one of the coupling transformers is driven by switching circuitry in the dimming module. The switching circuitry is pulse width modulated to control the average brightness of the light generated by the electrodeless lamp. An exemplary application for the dimmable electrodeless light source is as a backlight for a video display device, such as a liquid crystal display unit. The dimmable electrodeless light source further includes a magnetic shield device that is operably positioned with respect to the electrodeless lamp. The magnetic shield device produces a magnetic field that substantially opposes, and cancels, the magnetic field that is produced by the electrodeless lamp when energized. In an alternative embodiment, the magnetic shield device produces a magnetic field which, when combined with the lamp magnetic field, results in a total magnetic field that is substantially constant regardless of the energization level of the lamp (e.g., totally energized or dimmed). The magnetic shield thus reduces visual artifacts that might otherwise appear on a video display unit due to a variation of the magnetic field produced by the lamp.

A coil unit includes a planar coil that has a transmission side and a non-transmission side, a magnetic sheet provided over the non-transmission side of the planar coil, and a heat sink/magnetic shield plate stacked on a side of the magnetic sheet opposite to a side that faces the planar coil, the heat sink/magnetic shield plate dissipating heat generated by the planar coil and shielding magnetism by absorbing a magnetic flux that has not been absorbed by the magnetic sheet. The heat sink/magnetic shield plate has a thickness larger than that of the magnetic sheet.

A tunneling magneto-resistive reader includes a sensor stack separating a top magnetic shield from a bottom magnetic shield. The sensor stack includes a reference magnetic element having a reference magnetization orientation direction and a free magnetic element having a free magnetization orientation direction substantially perpendicular to the reference magnetization orientation direction. A non-magnetic spacer layer separates the reference magnetic element from the free magnetic element. A first side magnetic shield and a second side magnetic shield is disposed between the top magnetic shield from a bottom magnetic shield, and the sensor stack is between the first side magnetic shield and the second side magnetic shield. The first side magnetic shield and the second side magnetic shield electrically insulates the top magnetic shield from a bottom magnetic shield.

A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A receiver on the BHA receives signals that are indicative of formation resistivity and distances to bed boundaries. A combination of electromagnetic shielding and magnetostatic shielding enables determination of distance to an interface ahead of the drillbit.

The transceiver includes a housing, a transmitting optical sub-assembly mounted in the housing, a receiving optical sub-assembly mounted in the housing, a first electrical connector associated with the transmitting optical sub-assembly, a second electrical connector associated with the receiving optical sub-assembly, and an electro-magnetic shield mounted on the housing. The housing includes a first fiber optic connector receptacle, a second fiber optic connector receptacle, and a first side, and the housing is made of an electrically conductive material.

Embodiments of the invention provide a perpendicular recording magnetic head capable of reducing leakage magnetic fields from the soft magnetic films on the air bearing surface side and reducing the protrusion of the soft magnetic films in the direction of the air bearing surface side due to thermal deformation of the soft magnetic films. In one embodiment, the write functional section includes a coil conductor, second soft magnetic film pattern and first soft magnetic film pattern that cover the coil conductor from top and bottom and are magnetically coupled to each other, and a main magnetic pole piece determining a track width. The read functional section includes a reading element sandwiched between two magnetic shield films. A pedestal magnetic pole pattern is formed at the frontal end position of the first soft magnetic film pattern.

A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A pair of receivers on the BHA receive signals that are indicative of formation resistivity and distances to bed boundaries. A time dependent calibration factor or a time-independent calibration factor may be used to combine the two received signals and estimate the distance to bed boundaries that are unaffected by the drill conductive body. Further improvement can be obtained by using copper shielding.

The invention discloses a permanent magnet biased bearingless switched reluctance motor, which comprises stator back yokes, permanent magnets, stator suspension cores, stator torque cores, magnetic shields, suspension winding coils, torque winding coils, rotor cores and a shaft, wherein the stator suspension cores are wound with the suspension winding coils; the stator back yokes are arranged outside the stator suspension cores and connected with the stator suspension cores; the permanent magnets are arranged between the two stator back yokes; the magnetic shields and the stator torque cores are arranged in stator suspension core slots; the magnetic shields are positioned between the suspension stator windings and the stator torque cores; the rotor cores are arranged in the stator suspension cores and the stator torque cores; gas are reserved between the rotor cores and each of the stator suspension cores and the stator torque cores to form air gaps; and the shaft is arranged in the rotor cores. By the permanent magnet biased bearingless switched reluctance motor, decoupling control over torque and suspending power is realized to bring convenience to high-speed running; and a suspension biased magnetic flux is provided by the permanent magnets to reduce suspension power consumption and improve the efficiency of the motor.