Abstract: A magnetizing coil unit and a method of making a magnetizing coil unit is provided. The coil includes a solenoid coil having a coiled copper sheet in which the width of the copper sheet is equal to the height of the solenoid coil. A magnetizing assembly includes a plurality of magnetizing coil units.

Abstract: A permanent magnet assembly for an imaging apparatus having a permanent magnet body having a first surface and a stepped second surface which is adapted to face an imaging volume of the imaging apparatus, wherein the stepped second surface contains at least four steps.

Abstract: A magnetizing coil unit and a method of making a magnetizing coil unit is provided. The coil includes a solenoid coil having a coiled copper sheet in which the width of the copper sheet is equal to the height of the solenoid coil. A magnetizing assembly includes a plurality of magnetizing coil units.

Abstract: A permanent magnet assembly comprising a fixed permanent magnet body and a movable permanent magnet body which is movable relative to the fixed permanent magnet body.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: A pole piece for use in an open magnet includes a magnetizable body of generally cylindrical shape and made of a ferromagnetic material with a plurality of concentrically-arranged, annular-shaped, radially spaced-apart grooves formed in the inner surface of the pole piece. A plurality of annular-shaped, electrically conductive coils are disposed within the grooves. The pole piece with recessed shielding coils is situated within a cryogenic vessel to maintain the pole pieces at a uniform cryogenic temperature. The result is an open magnet structure which provides a highly uniform, high field, open field of view for MRI with a well-contained stray field.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: An imaging apparatus, such as an MRI system, contains at least one layer of soft magnetic material between the yoke and each permanent magnet. This imaging apparatus may be operated without pole pieces due to the presence of the soft magnetic material. The permanent magnets may be fabricated by magnetizing unmagnetized alloy bodies after the unmagnetized alloy bodies have been attached to the yoke.

Abstract: A pole piece for use in an open magnet includes a magnetizable body of generally cylindrical shape and made of a ferromagnetic material with a plurality of concentrically-arranged, annular-shaped, radially spaced-apart grooves formed in the inner surface of the pole piece. A plurality of annular-shaped, electrically conductive coils are disposed within the grooves. The pole piece with recessed shielding coils is situated within a cryogenic vessel to maintain the pole pieces at a uniform cryogenic temperature. The result is an open magnet structure which provides a highly uniform, high field, open field of view for MRI with a well-contained stray field.

Abstract: A magnet, such as an open magnetic-resonance-imaging (MRI) magnet) has a first assembly including a superconductive main coil and a magnetizable pole piece which, during magnet operation, has a temperature equal to generally the temperature of the main coil. In one example, a cryogenic-fluid (e.g., liquid helium) dewar encloses the main coil, and the dewar has an interior surface defined in part by a surface portion of the pole piece. A method for providing a homogeneous imaging volume for a magnet includes steps to construct the above-described magnet.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet, includes a main coil and includes a shielding coil positioned radially outward from the main coil. A magnetizable member is positioned radially outward from the main coil and radially inward from the shielding coil to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main coil and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet includes a main coil, a correction coil, and a shielding coil positioned radially outward from the main and correction coils. Two magnetizable members are positioned radially outward from the main and correction coils and radially inward from the shielding coil to shorten the magnet, to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main and correction coils and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet includes a main coil, a magnetizable article, and a shielding coil positioned radially outward from the main coil and magnetizable article. Two magnetizable members are positioned radially outward from the main coil and magnetizable article and radially inward from the shielding coil to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main coil and magnetizable article and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: A magnet, such as an open magnetic-resonance-imaging (MRI) magnet) has a first assembly including a superconductive main coil and a magnetizable pole piece which, during magnet operation, has a temperature equal to generally the temperature of the main coil. In one example, a cryogenic-fluid (e.g., liquid helium) dewar encloses the main coil, and the dewar has an interior surface defined in part by a surface portion of the pole piece. A method for providing a homogeneous imaging volume for a magnet includes steps to construct the above-described magnet.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil, a magnetizable member not carrying an electric current and spaced apart from and proximate the main and shielding coils, and a magnetizable pole piece spaced apart from the magnetizable member: The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.