Magnetic materials, passive shims and magnetic resonance imaging systems

A technology of ferromagnetic materials and gaskets, which can be used in magnetic materials, magnetic resonance measurement, magnetic objects, etc., and can solve problems such as increasing magnetic field inhomogeneity.

Inactive Publication Date: 2005-04-13
GENERAL ELECTRIC CO
View PDF2 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This leads to an increase in the inhomogeneity of the magnetic field

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Magnetic materials, passive shims and magnetic resonance imaging systems
  • Magnetic materials, passive shims and magnetic resonance imaging systems
  • Magnetic materials, passive shims and magnetic resonance imaging systems

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] The present invention has realized that the shim may include a material exhibiting an increase in spontaneous magnetization (i.e., dM ) with increasing temperature in a predetermined temperature range. s / dT>0) material. This material can be used to eliminate or reduce the situation where the magnetization of the spacer decreases with increasing temperature and causes the magnetic field of the magnet to be non-uniform.

[0023] While some ferromagnetic materials exhibit a negative change in magnetization with temperature, there are other materials that exhibit a positive change in spontaneous magnetization with temperature under certain conditions. In one embodiment of the invention, the spacer comprises a magnetic material capable of exhibiting a positive change in spontaneous magnetization with temperature over a predetermined temperature range, wherein the magnetic material is capable of changing the magnetic field.

[0024] Preferably, the spacer comprises one or m...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The present invention provides a magnetic material, a passive gasket and a magnetic resonance imaging system. A shim (24, 34, 54) adapted for altering a magnetic field of a magnet (12, 14, 36) includes a first material which exhibits an increase in spontaneous magnetization with an increase in temperature for a predetermined temperature range.

Description

technical field [0001] The present invention relates to magnetic materials. In particular, the invention relates to magnetic materials used in spacers for magnetic resonance imaging systems. Background technique [0002] Magnetic resonance imaging (MRI) systems generally include superconducting magnets that generate a primary magnetic field within the imaging volume. Inhomogeneities in the primary magnetic field are the result of manufacturing tolerances of the magnets as well as equipment and site conditions. The inhomogeneity of the magnetic field distorts the positional information in the imaging object and degrades the quality of the image. In order to obtain high-quality imaging, the imaging object must have low magnetic field inhomogeneity. Shimming is a known technique for reducing the inhomogeneity of the primary magnetic field. The primary magnetic field can be described as a large constant field with a small inhomogeneous field component superimposed on the con...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): A61B5/055G01R33/3873H01F1/00H01F1/04H01F1/055H01F1/057H01F41/02
CPCG01R33/3873H01F1/0558H01F1/0578H01F41/0266
Inventor I·S·雅各布斯
Owner GENERAL ELECTRIC CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap