A superconducting magnet assembly with a reinforced coil region (3) having a layered conductor coil assembly (10) forming cylindrical conductor layers (11, . . . ), each having plural circular conductor turns (12) centered around and aligned along the axis of cylindrical symmetry (z). The reinforced coil region further includes a layered corset coil assembly (20) having an inner radius bigger than an outer radius of the layered conductor coil assembly (10), and a corset sheet assembly (30) including a foil element forming a corset sheet (31, . . . ). A cross section of the corset sheet with any plane perpendicular to the z-axis forms a segmented circle centered around the z-axis, the radius of which is bigger than that of one of the conductor layers and smaller than that of another of the conductor layers. In addition, the segmented circle covers at least 90% of a full circle but has at most four segments. The assembly provides mechanical reinforcement against radial magnetic forces.

A method for performing magnetic resonance imaging is provided. The method includes providing a magnetic resonance imaging system comprising: a radio frequency receive system comprising a radio frequency receive coil, and a housing, wherein the housing comprises a permanent magnet for providing an inhomogeneous permanent gradient field, a radio frequency transmit system, and a single-sided gradient coil set. The method also includes placing the receive coil proximate a target subject; applying a sequence of chirped pulses via the transmit system; applying a multi-slice excitation along the inhomogeneous permanent gradient field; applying a plurality of gradient pulses via the gradient coil set orthogonal to the inhomogeneous permanent gradient field; acquiring a signal of the target subject via the receive system, wherein the signal comprises at least two chirped pulses; and forming a magnetic resonance image of the target subject.

A coil assembly includes: a radio frequency (RF) coil operable to be placed over a portion of a subject; a quarter-wave transformer coupled to the RF coil and configured to transform a characteristic impedance of the RF coil; and a diode placed behind the quarter-wave transformer and away from the RF coil, wherein the diode is operable to: (i) when the diode is forward biased, the diode turns the quarter-wave transformer into an open circuit such that the power amplifier drives the RF coil with sufficient electrical power for the RF coil to transmit an RF pulse into the portion of the subject; and (ii) when the diode is provided zero or revers bias, the diode turns the quarter-wave transformer into a short circuit such that the RF coil is detuned from a Lamor frequency of nuclei of interest immersed in the main magnet.

In some aspects, a magnetic system for use in a low-field MRI system. The magnetic system comprises at least one electromagnet configured to, when operated, generate a magnetic field to contribute to a B.sub.0 field for the low-field MRI system, and at least one permanent magnet to produce a magnetic field to contribute to the B.sub.0 field.

Methods and apparatuses for homogenizing or correcting the magnetic fields of magnets, particularly the magnetic fields employed in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) applications. There are disclosed passive shims for making such homogenizations or corrections, methods for making such shims, and a method and apparatus for creating desirable correction fields in which the correction field strength has limited harmonic content, near continuous value of field strength, and occupies minimal space in the magnet.

According to one embodiment, a magnetic resonance imaging apparatus installed in a shield room comprises a gantry, a table, and at least one unit. The gantry includes a static magnetic field magnet, a gradient magnetic field coil, and an RF coil. The subject is to be placed on the table. The at least one unit relates to control of the magnetic resonance imaging apparatus and is configured to include at least one opening on a upper surface on for maintenance and inspection.

A superconducting magnet device includes a vacuum container having a tubular barrel portion; a magnet assembly including a superconducting coil, a refrigerant tank, and a radiation shield, the magnet assembly being housed in the vacuum container; a supporting block fixed to the barrel portion and protruding beyond the barrel portion to the inside of the vacuum container; and a connecting portion which connects the magnet assembly and the supporting block to each other such that the magnet assembly is spaced apart from the barrel portion within the vacuum container. The connecting portion has thermal conductivity lower than thermal conductivity of the supporting member. The supporting member receives weight of the magnet assembly via the connecting portion while protruding inwardly beyond at least an outer circumference surface of the radiation shield of the magnet assembly.

A method to produce a magnet arrangement, the method having steps of selecting a depth of investigation to be achieved by a downhole tool, identifying a desired magnetic field strength at the depth of investigation, producing a set of magnets to be incorporated into the downhole tool, sorting the set of magnets based on a quality of each of the magnets and optimizing the set of magnets such that the quality of each of the magnets results, when arranged, in the desired magnetic field strength at the depth of investigation and wherein the optimizing minimizes a cost function of the set of magnets produced.

The present invention is such that a main body neither drops out nor is destroyed. A plurality of brackets (4), provided on a side surface of a main body (2) in which a superconducting magnet is mounted internally in a state in which each protrudes therefrom, are each supported by a stand (3) from the bottom, and enclosing members (5) are attached to the side surface of the main body (2) with a prescribed space (a) opened from the bottom of the brackets (4). At least part of the inside surface of an enclosing member (5) surrounds a stand (3) in a non-contact state.

A method for manufacturing a device having a three-dimensional magnetic structure includes applying or introducing magnetic particles onto or into a carrier element. A plurality of at least partly interconnected cavities are formed between the magnetic particles, which contact one another at points of contact, by coating the arrangement of magnetic particles and the carrier. The cavities are penetrated at least partly by the layer generated when coating, resulting in the three-dimensional magnetic structure. A conductor loop arrangement is provided on the carrier or a further carrier. When a current flows through the conductor loop, an inductance of the conductor loop is changed by the three-dimensional magnetic structure, or a force acts on the three-dimensional magnetic structure or the conductor loop by a magnetic field caused by the current flow, or when the position of the three-dimensional magnetic structure is changed, a current flow is induced through the conductor loop.