| 摘要 |
PURPOSE:To obtain a tomographic image in a short time, by simultaneously imparting gradient magnetic fields in Z and Y directions to a body to be checked under the uniform magnetic field, applying an electromagnetic wave of 90 deg. pulses, imparting a gradient magnetic field in the Y direction and an electromagnetic wave of 180 deg. after a specified time, and detecting and processing an NMR signal. CONSTITUTION:A static magnetic field control circuit 2 flows a current to a static magnetic field coil 1, and a static magnetic field HO is imparted to a body to be checked. A controller 60 flows a current to exciting coils 31, 32, and 33 through a gradient magnetic field control circuit 4, and a (z) gradient magnetic field Gz and a (y) gradient magnetic field Gy are imparted. Then, a signal from an oscillator 6 is applied to a coil 5 through a gate circuit 61 and a power amplifier 62, and 90 deg. pulses are imparted. Then an NMR signal is detected by a detecting coil 7. After the decay time of the signal, 180 deg. pulses are imparted under the magnetic field Gy by the similar way, and the NMR signal is detected. The signals undergo Fourier conversion through a preamplifier 71, a phase detector 72, and a wave memory 73. This procedure is repeated in a time series, and the tomographic image can be obtained in a short time. |
