A common mistake in biomagnetic experimentation is the assumption that Helmholtz coils provide uniform magnetic fields; this is true only for a limited volume at their center. Substantial improvements on this design have been made during the past 140 years with systems of three, four, and five coils
General Expressions for the Magnetic Field and Stored Energy of Elliptic Cylinder Coils
โ Scribed by Q. Liu; D.G. Hughes; P.S. Allen
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 163 KB
- Volume
- 113
- Category
- Article
- ISSN
- 1064-1866
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โฆ Synopsis
General expressions involving Mathieu functions are derived for an elliptical cylinder and used it to design a longitudinal (z) the magnetic field and stored energy associated with distributed gradient coil. However, the optimal design of even a z gradient currents, flowing, both azimuthally and axially, on the surface of coil requires an axial as well as an azimuthal component of an elliptic cylinder. These expressions can be used to design ellipcurrent, and to construct a transverse gradient coil based on tical gradient coils of minimum inductance for MRI, as well as elliptical geometry, a large axial component is essential.
elliptical coils that will generate a uniform magnetic field or higher Our purpose in this paper is to derive general expressions order shim fields.
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