Apparatus for passive control of magnet homogeneity

申请公布号：US6583696(B1)

申请号：US19990365255

申请日期：1999.07.30

申请公布日期：2003.06.24

申请人：

FONAR CORPORATION, INC.

发明人：DATSIKAS THOMAS

分类号：G01R33/3873;H01F7/02;(IPC1-7):H01F7/00

主分类号：G01R33/3873

摘要：A method and apparatus for passively shimming a magnet. A magnetic field produced by the magnet is measured and modeled in the form of a Legendre polynomial expansion having a predetermined number of harmonic terms. The degree of non-homogeneity in the measured field is determined by examining the harmonic terms. A shim is then designed to correspond to a magnitude change of a harmonic term of the polynomial expansion in order to improve the homogeneity of the magnetic field. A metal plate is connected to or placed near a pole of the magnet, the shim is placed against the metal plate, and a plastic plate is attached to the metal plate such that the shim is held in place in a predetermined location against the metal plate.

PROCESS FOR MALTING GRAIN

IMPROVED GRAPHITE COMPOSITIONS AND LUBRICATING COMPOSITIONS CONTAINING THEM

IMPROVEMENTS IN HORIZONTALLY HINGED FOLDABLE DOORS

CLOTHES HANGING DEVICE

CONTAINER INDEXING APPARATUS

SILICA CONTAINING CATALYST PREPARATION AND USE

PRODUCTION OF TITANIUM COMPOUNDS FROM ORES CONTAINING OXIDES OF TITANIUM AND IRON

ROLLING BEARINGS

COKE FORMING TENDENCY OF CATALYSTS AND SORBENTS

POLYMER BLENDS

BEARING COMPONENT

CHECK VALVES ESPECIALLY INTENDED FOR USE IN A POWER BRAKING SYSTEM

ENCLOSURES SCREENED FROM HIGH-FREQUENCY ELECTROMAGNETIC FIELDS

SYNTHETIC COMPLEX CONJUGATE FILAMENT AND PROCESS OF MANUFACTURING THE SAME

DEVICES FOR CLAMPING TUBULAR MEMBERS

GEARBOXES

PROCESS AND APPARATUS FOR THE PRODUCTION OF STOPS IN SLIDE FASTENERS

DISPENSING APPARATUS

GRIDS FOR LEAD-ACID BATTERIES OR CELLS

GAS TURBINE ENGINES