| 摘要 |
PROBLEM TO BE SOLVED: To decide a delay of time with a simple method and calibrate by analyzing a calibration picture which is formed at an isocenter for a gradient magnetic field system and other offset positions and deciding whether a delay after a calibration is within a permissible range, or not, and repeating the above process by controlling the timing of a pulse. SOLUTION: A picture which is shown by a slice 120 in an isocenter for a gradient magnetic field system is formed in a calibration sequence. Furthermore, a slice 122 and a slice 124 are formed at a position which is offset from an isosenter. These picture data are formed then a region of interest 136 for an inside of a central part for a picture matrix and so forth is set in each picture so as to compare when the picture is calibrated. The picture is analyzed then an average signal level in the region of interest is obtained. Then the above process is repeated with chancing a delay between an RF ripple and a gradient ripple systematically. And a delay which gives the smallest difference among the average strength for each picture is selected as suitable delay.
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