PROBLEM TO BE SOLVED: To suppress deterioration of positional accuracy due to uneven rotation of a rotor in mechanical scanning of a vibrator and improve spatial resolution of an acoustic line signal. SOLUTION: A transmission unit that supplies a transmission pulse to a transducer to transmit an ultrasonic beam from the transducer, and a train of reception signals is generated based on a reflected wave received by the transducer based on the transmission of the ultrasonic beam. The receiving unit, the received signal sequence and the rotation angle corresponding to the received signal sequence are stored in association with each other, and the received signal sequence is synthesized based on the rotation angle related to the transmission. The transmitting unit includes a synthesizing unit that generates frame data of acoustic line signals, and when n is a natural number of 2 or more, the transmitting unit changes the rotation angle for each rotation for n consecutive rotations and transmits the ultrasonic wave. By performing transmission and reception, the process of transmitting ultrasonic waves at n different rotation angles is repeated in n consecutive rotations, and the combining unit creates a sequence of a plurality of reception signals obtained corresponding to different rotations. Frame data of acoustic line signal after synthesis Generated. [Selection diagram] Figure 1【課題】振動子の機械走査におけるロータの回転ムラに起因する位置精度の低下を抑制し音響線信号の空間分解能を高める。【解決手段】振動子に送信パルスを供給して振動子から超音波ビームを送信させる送信部と、超音波ビームの送信に基づき振動子が受波した反射波に基づいて受信信号の列を生成する受信部と、受信信号の列と当該受信信号の列に対応する回転角とを、対応させて記憶する受信信号保持部と、受信信号の列を送信に係る回転角を基準に合成して音響線信号のフレームデータを生成する合成部とを備え、送信部は、ｎを２以上の自然数としたとき、連続するｎ回の回転それぞれにおいて、回転毎に回転角を異ならせて超音波の送受信を行うことにより、連続するｎ回の回転においてｎの異なる回転角にて超音波の送信を行う処理を繰り返し、合成部は、異なる回転に対応して得られた複数の受信信号の列を合成して音響線信号のフレームデータを生成する。【選択図】図１
