PROBLEM TO BE SOLVED: To provide an apparatus which, even when a medium different from a subject is present in a propagation path of an acoustic wave, can highly accurately acquire information of the subject.SOLUTION: An apparatus according to the present invention includes acquisition means which: uses information about the longitudinal wave acoustic velocity of a medium to determine, from among signals, a first signal of interest derived from an acoustic wave which has occurred in a reconstruction position and propagated as a longitudinal wave in the medium uses information about the transversal wave acoustic velocity of the medium to determine, from among signals, a second signal of interest derived from an acoustic wave which has occurred in the reconstruction position and propagated as a transversal wave in the medium and uses both the first signal of interest and the second signal of interest to acquire information of a subject in the reconstruction position when the incident angle is larger than the critical angle and is smaller than a virtual critical angle larger than the critical angle.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2018,JPO&INPIT【課題】 本発明は、音響波の伝搬経路内に被検体と異なる媒質が存在する場合であっても、被検体情報を精度良く取得することのできる装置を提供することを目的とする。【解決手段】 本発明に係る装置は、媒質の縦波音速に関する情報を用いて、信号の中から、再構成位置で発生し、縦波として媒質内を伝搬した音響波に由来する第1の注目信号を決定し、媒質の横波音速に関する情報を用いて、信号の中から、再構成位置で発生し、横波として媒質内を伝搬した音響波に由来する第2の注目信号を決定し、入射角が臨界角よりも大きく、かつ、臨界角よりも大きい仮想の臨界角よりも小さい場合に、第1の注目信号及び第2の注目信号の両方を用いて、再構成位置の被検体情報を取得する取得手段を有する。【選択図】 図1
