Gradient coils for therapy tomographs

US5414360A · kind A · utility

Assignee

• Bruker Analytische Messtechnik GmbH · DE

Inventors

• Michael Westphal · Boise, US
• Gunther Laukien · Rheinstetten, DE

Key dates

• Filing date: Sep 8, 1993
• Grant date: May 9, 1995
• Expiry date: Sep 8, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/385
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A nuclear spin resonance (NMR) measuring device, in particular an NMR tomography apparatus with a preferentially superconducting main field coil which is capable of producing, within a measurement volume whose center is coincident with the origin of a Cartesian coordinate system x, y, z, a homogeneous static magnetic field B.sub.0 in the direction of the z-axis of this coordinate system and with a tesseral gradient coil system for the production of magnetic gradient fields with a largely linear dependence within the measuring volume in a direction perpendicular to the z-axis, whereby the gradient coil system comprises at least four largely identical saddle-type partial coils arranged symmetrically with radial and axial separations from the coordinate origin, the partial coils each exhibiting two electrically conducting segments which run about the z-axis in the azimuthal direction one segment (21) of which has as small a radial separation r.sub.1 and the other segment (22) as large a radial separation r.sub.2 as possible from the z-axis, is characterised in that both azimuthal segments (21, 22) exhibit an axial separation from each other in the direction of the z-axis, whereby the …