Device and method for compensation of magnetic field disruptions in highly homogeneous magnetic fields
US7474976B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 2007 |
| Grant date | Jan 6, 2009 |
| Priority date | — |
| Expiry date | Jul 23, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/56509
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for compensating field disruptions in magnetic fields of electromagnets with high field homogeneity, in particular, for stabilizing the H0 field of an MR measuring system, comprising at least one field detector (31) for detecting interfering signals (Uin), at least one control loop for processing the detected interfering signals (Uin), and at least one compensation coil (34) to which the detected and processed interfering output signals (Uout) are transferred and which generates a correction field for compensating the interfering signals (Uin), is characterized in that at least one of the control loops comprises a multi-selective filter system (35) which comprises one or more parallel connected selective filter elements whose center frequencies can be tuned either once or in an adaptive fashion to the frequency values of the interfering signals (Uin) to be compensated for, wherein the outputs of these filter elements are connected to at least one of the compensation coils (34). The inventive device permits selective detection of periodic field disturbances with high frequency components while a major part of the existing noise is faded out, thereby increasing the SINO.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.