MEASURING METHOD OF STATIC MAGNETIC FIELD INTENSITY DISTRIBUTION OF NMR INSPECTION APPARATUS

摘要

PURPOSE:To measure a static magnetic field intensity distribution rapidly, by making different prescribed time intervals of detection of nuclear magnetic resonance, and by calculating an error of the static magnetic field intensity distribution on the basis of the output of a computer on the occasion. CONSTITUTION:An object 2 is inserted into a magnet 1, and a current is supplied to coils 4X and 4Y and a coil 5 generating an inclined magnetic field in the direction (z) by driving units, 6, 7 and 8 respectively. A high-frequency magnetic field exciting a nuclear spin is generated by a method wherein a high-frequency wave generated by a synthesizer 12 is subjected to wave-shaping and power amplification by a modulating unit 13 and a current is supplied to a coil 3. Signals from the object 2 are received by said coil 5, passed through an amplifying unit 14 and then subjected to perpendicular detection by a detecter 15. Then, they are inputted to a computer 9 and stored in memories 17 and 18. A time interval from the impression of a 90 deg. pulse high-frequency magnetic field to the impression of 180 deg. high-frequency magnetic filed is made different from a time interval from the impression of the 180 deg. pulse high-frequency magnetic field to the measurement of a nuclear magnetic resonance signal by the computer 9, and static magnetic field intensity distribution is calculated on the basis of the output of said computer corresponding to the difference between the time intervals.