PROBLEM TO BE SOLVED: To accurately acquire environmental sound velocity without bringing about a drop in processing or diagnostic efficiency.SOLUTION: Each element of an ultrasonic probe is driven on the basis of a prescribed transmission delay time, and ultrasonic wave transmission is carried out, the focus of which is focused at a prescribed transmission focus point. An actual focus point or an effective region including the focus point is determined according to the ultrasonic transmission to the transmission focus point, on the basis of a reception signal received by each element according to the reflected waves reflected due to the ultrasonic wave transmission to the transmission focus point.COPYRIGHT: (C)2012,JPO&INPIT【課題】処理効率や診断効率の低下を招くことなく、高精度に環境音速を取得する。【解決手段】超音波プローブの各素子を所定の送信遅延時間に基づいて駆動して所定送信フォーカス位置に焦点が合わせられた超音波の送波を行い、その送信フォーカス位置への超音波の送波により反射された反射波に応じて各素子によって受信された受信信号に基づいて、上記送信フォーカス位置への超音波の送波による実際の焦点位置またはその焦点位置を含む有効域を決定する。【選択図】図2
