Even in the case of using the electro-acoustic transducer with high nonlinearity, and performs non-linear imaging obtained by extracting non-linear components more. And to extract the non-linear components for the same position of the imaging target, it is transmitted twice an ultrasound beam from the transmitting unit, is calculated for the signal processing unit receiving signals obtained for each of the two transmissions, included in the received signal . Of the two transmissions, and is driven by passing a transmission signal from the transmitting unit to all of the electroacoustic transducer of the plurality of the one of the other, once selected only a part of the electroacoustic transducer of the multiple is driven by pass the transmit signal basis.非線形性の高い電気音響変換素子を用いた場合であっても、より多くの非線形成分を抽出した非線形イメージングを行う。撮像対象の同位置に対して、送信部から超音波ビームを2回送信させ、2回の送信のたびに得た受信信号を信号処理部に演算させ、受信信号に含まれる非線形成分を抽出させる。2回の送信のうち、1回は複数の電気音響変換素子の全てに送信部から送信信号を受け渡して駆動させ、他の1回は、複数の電気音響変換素子のうちの一部のみに選択的に送信信号を受け渡して駆動させる。
