Magnetic resonance apparatus having a quadrature RF coil system
US4931734A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1989 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | Apr 11, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/3678
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A quadrature mode rf coil system in a magnetic resonance apparatus includes a pair of orthogonal rf coils which, for excitation and/or detection are coupled to an rf source or receiver by an electronic switching circuit built up from inductances and capacities. The switching circuit includes preferably frequency adjustable 90.degree. first delay lines feeding each coil which transforms the 50.OMEGA. coil impedance of each coil to 100.OMEGA. so that the parallel combination of transformed impedances is 50.OMEGA.. A second 90.degree. delay line is cascaded with the first delay line feeding one of the coils to establish a 90.degree. phase difference between the coils.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.