PROBLEM TO BE SOLVED: To achieve imaging in which all three characteristics, i.e., frame rate, spatial resolution, and contrast medium selectivity, are balanced in an ultrasonic contrast imaging method for extracting signals, specific to a contrast medium, and imaging.SOLUTION: An ultrasonic imaging apparatus includes a decoding section 13 that transmits/receives a first chirp signal, which increases in frequency with time, and a second chirp signal, which is obtained by inverting the first chirp signal on a time base, and that holds decode filters corresponding to coded lines when the chirp signal and the pulse signal are decomposed into the coded lines. The decode filters are used for reception echoes corresponding to two chirp signals. Outputs from the two decode filters are passed through a subtractor 14 and a difference between them is obtained, thereby enabling both contrast medium selectivity and spatial resolution.COPYRIGHT: (C)2010,JPO&INPIT【課題】造影剤特異的な信号抽出と画像化を行う超音波造影撮像法において、フレームレート、空間分解能、造影剤選択性の3つの特性すべてにおいてバランスのとれた撮像を行う。【解決手段】時間とともに周波数の上がっていく第一のチャープ信号と、これを時間軸上で反転した第二のチャープ信号を用い、それぞれで送受信を行い、チャープ信号をパルス信号と符号化列に分解したときの符号化列に対応したデコードフィルタを保持したデコード部13を備え、このデコードフィルタを二つのチャープ信号に対する受信エコーに適応し、二つのデコードフィルタ出力を減算器14に通して差分をとることにより、造影剤選択性と空間分解能を両立する。【選択図】図1
