Circuit for detecting AC magnetic field due to magnetic resonance with a variable resistance for noise suppression
US4875010A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1988 |
| Grant date | Oct 17, 1989 |
| Priority date | — |
| Expiry date | Mar 28, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/0358
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a signal detecting circuit of, for example, an NMR apparatus, a signal transmission path transmits an AC magnetic flux signal to be superposed on a DC magnetic field whose strength does not change with time during a period of signal detection. The signal transmission path comprises a superconducting closed loop including a receiving coil receiving the AC magnetic flux signal, an input coil applying the received AC magnetic flux signal as an input to a flux meter, and a variable resistor replacing part of the superconducting closed loop and having its resistance value changed in relation to a change in the strength of the DC magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.