| 摘要 |
PURPOSE:To make it possible to obtain a perfect tomographic image at every magnetic field by receiving a FID signal once, by continuously changing a perturbation magnetic field during the reception of the FID signal so that said magnetic field comes to mutually different history to each cell. CONSTITUTION:Water is accumulated in a coil L1 and a static magnetic field H00 is preliminarily applied from a direction at right angles to the axis of the coil. A gradient magnetic field Gz is applied to an object to be detected and a RF pulse (90 deg. pulse) obtained by modulating the output of an oscillator OSC on the basis of the modulation signal of a modulator BM1 is applied thereto. Succeedingly, a gradient magnetic field of H00+H is applied while a FID (Free Induction Decay) signal is detected by the coil L1 to be once received in a wave form memory apparatus through a receiving amplifier RA. In this case, an image is reconstituted corresponding to the content of the memory apparatus on the basis of chirp conversion such that the transition of the spin resonance frequency of each local part. By this method, the FID signal containing the data of all cells and capable of forming one picture is obtained by one trial and the reconstitution of the image can be performed. |
