In many cases after degaussing the field distribution in a magnetic material there may be regions within the magnetic material that have ordered domains that contribute a remnant field. There is the need to reduce or eliminate non-uniform fields within a volume of interest left after degaussing a magnetic shield. Degaussing coils surrounding a metal shield can be used to favorably order magnetic domains within the material to counteract the remnant fields left behind following imperfect degaussing. The remnant field value can be measured and a small current may be applied through the degaussing coils. After removing the current, the field can be measured again and a higher current may be applied again through the coils. Repeated applications of currents and field measurement will progressively order domains in the direction of the applied field, resulting in a reduction of the net field and lower field gradient across the volume of interest.

A magnetism booster assembly includes a body having a first end and a second end. The body defines a bore and a cavity formed separately from the bore. The bore extends between the first end and the second end. The cavity has a first opening adjacent the first end of the body and a second opening adjacent the second end of the body. The magnetism booster assembly also includes a magnet positioned within the cavity.

A magnetism booster assembly includes a body having a first end and a second end. The body defines a bore and a cavity formed separately from the bore. The bore extends between the first end and the second end. The cavity has a first opening adjacent the first end of the body and a second opening adjacent the second end of the body. The magnetism booster assembly also includes a magnet positioned within the cavity.

Disclosed is a magnetic circuit structure of a transducer comprising a static magnetic field generating device which comprises magnet sets, the magnet sets comprise a first magnet set magnetized in a moving direction of the transducer, a second magnet set and a third magnet set located in a direction orthogonal to a static magnetic field generated by the first magnet set, a magnetization direction of the second magnet set is orthogonal to that of the first magnet set, a magnetization direction of the third magnet set is orthogonal to that of the second and first magnet sets, the second and third magnet sets increase a magnetic induction intensity of the static magnetic field. The magnetic circuit structure of the transducer in the present disclosure can effectively solve the problem that a driving force of the transducer applying thereof is not sufficient, thus increasing the efficiency of electric-to-mechanical conversion.

A method of producing a permanent magnet shim configured to improve a profile of a B.sub.0 magnetic field produced by a B.sub.0 magnet is provided. The method comprises determining deviation of the B.sub.0 magnetic field from a desired B.sub.0 magnetic field, determining a magnetic pattern that, when applied to magnetic material, produces a corrective magnetic field that corrects for at least some of the determined deviation, and applying the magnetic pattern to the magnetic material to produce the permanent magnet shim. According to some aspects, a permanent magnet shim for improving a profile of a B.sub.0 magnetic field produced by a B.sub.0 magnet is provided. The permanent magnet shim comprises magnetic material having a predetermined magnetic pattern applied thereto that produces a corrective magnetic field to improve the profile of the B.sub.0 magnetic field.

Embodiments of the present disclosure relate to methods and systems for switching a magnetic field external to a magnet assembly having two permanent magnets, including a fixed permanent magnet portion and a switching permanent magnet portion, where a switching magnetic field is used to switch the magnetization of the switching permanent magnet portion, but not switch the magnetization of the fixed permanent magnet portion. In this way, the fixed permanent magnet portion has a fixed magnetization, such that the direction of magnetization of the fixed permanent magnet portion remains the same during switching of the magnetization of the switching permanent magnet portion, and the switching permanent magnet portion has a switching magnetization, such that the direction of magnetization of the switching permanent magnet portion is switched during switching of the magnetization of the switching permanent magnet portion.

A device for accommodating and magnetizing a tissue-penetrating medical device of various lengths, with or without a cover covering a portion or the entirety of the tissue-penetrating medical device, is disclosed including a sleeve member having an open proximal end, a distal end, an inner surface, an outer surface having a graduated injection depth gauge to indicate needle penetration depth when the cover is placed into a magnetizer, and a hollow body extending between the proximal end and the distal end to form a protective closure over a shaft of a tissue-penetrating medical device. A device having one or more magnetizing elements sectioned into a plurality of movable segments pivoting around an axis to accommodate needles with different lengths is also disclosed. Also disclosed is a device having one or more magnetizing means mounted on a movable element to magnetize needles of various lengths.

A method for checking the coercive field strength of magnetic pigments of an areal sample which are contained in a magnetic region of the areal sample includes: after a magnetization of the areal sample until saturation, a first partial counter-magnetization of the magnetic pigments out by a magnetizing device, and a first measurement of a first magnetization value of the partially counter-magnetized magnetic pigments are carried out. The measured magnetization values are transmitted from the measuring device to a checking device. The checking device checks the magnetization values of the partially counter-magnetized magnetic pigments for ascertaining a check result that relates to the coercive field strength of the magnetic pigments and transmits the check result relating to the coercive field strength to an output device connected to the checking device.

A method for checking the coercive field strength of magnetic pigments of an areal sample which are contained in a magnetic region of the areal sample includes: after a magnetization of the areal sample until saturation, a first partial counter-magnetization of the magnetic pigments out by a magnetizing device, and a first measurement of a first magnetization value of the partially counter-magnetized magnetic pigments are carried out. The measured magnetization values are transmitted from the measuring device to a checking device. The checking device checks the magnetization values of the partially counter-magnetized magnetic pigments for ascertaining a check result that relates to the coercive field strength of the magnetic pigments and transmits the check result relating to the coercive field strength to an output device connected to the checking device.

A distributed demagnetizing coil system, a shielding device, and a demagnetizing method. The system includes turns of demagnetizing coils evenly wound on each shielding surface of a shielding body in the shielding device at intervals and connecting wires provided on outer side of the shielding surface in an inflection manner. One half of each turn is located on inner side of the wound shielding body and the other half of each turn s located on outer side of the wound shielding body for providing corresponding demagnetizing magnetic fields to form a closed magnetic flux loop. One half of each connecting wire is connected to the corresponding demagnetizing coil, the other half of each connecting wire is reversely inflected along an original path and is connected to a power supply module, so that corresponding demagnetizing current is introduced into each demagnetizing coil connected to the connecting wire.