PROBLEM TO BE SOLVED: To prepare an RF pulse waveform excellent in the reproducibility of an ideal irradiation pattern and reduced in RF waveform power, as well as to improve the safety of an MRI subject by using such RF pulses.SOLUTION: The MRI apparatus is provided with a waveform control means that calculates high-frequency pulses and applies them to irradiation means. The waveform control means reads an RF pulse waveform vector from a first storage means storing a plurality of high-frequency waveform vectors, calculates a virtual irradiation pattern, and regarding the ideal and virtual irradiation patterns, calculates an high-frequency pulse waveform giving the minimum of the weighted total of the square of a difference in the absolute value and the square of a difference in the phase.COPYRIGHT: (C)2009,JPO&INPIT【課題】理想的な照射パターンの再現性に優れ、且つRF波形のパワーを低減したRFパルス波形を作成すること。および、そのようなRFパルスを用いた撮像を行なうことによりMRI被験者の安全性を向上させること。【解決手段】MRI装置は、高周波パルスを算出し、照射手段に適用する波形制御手段を備え、波形制御手段は、複数の高周波パルス波形ベクトルを格納する第1の記憶手段から高周波パルス波形ベクトルを読み出し、仮想照射パターンを算出し、理想照射パターンと仮想照射パターンについて、絶対値の差分の二乗と位相の差分の二乗との重み付け和の最小値を与える高周波パルス波形を算出する。【選択図】図2
