PROBLEM TO BE SOLVED: To provide a device capable of removing artifact at low cost and with a high degree of precision in a photoacoustic device.SOLUTION: A subject information acquisition device includes light irradiation parts 110 and 120, an acoustic wave probe 130 for receiving an acoustic wave generated in a subject due to a pulse light, and information acquisition parts 140 and 150 for acquiring characteristic information in the subject based on the received acoustic wave. The light irradiation parts perform first light irradiation for irradiating the pulse light a plurality of times within a predetermined time, and second light irradiation for irradiating a single pulse light after the first light irradiation. The information acquisition parts acquire third data which is a difference between first data acquired based on the acoustic wave generated the by first light irradiation and second data acquired based on the acoustic wave generated by the second light irradiation, and acquire the characteristic information in the subject using the third data. The predetermined time is shorter than the time from when a predetermined region in the subject is brought into an excitation state due to the pulse light until the excitation state is mitigated.SELECTED DRAWING: Figure 1【課題】光音響装置において低コストかつ精度よくアーチファクトを除去できる装置を提供する。【解決手段】光照射部１１０，１２０と、パルス光に起因して被検体内で発生した音響波を受信する音響波探触子１３０と、受信した音響波に基づいて被検体内の特性情報を取得する情報取得部１４０，１５０と、を有し、光照射部は、パルス光を所定の時間以内に複数回照射する第一の光照射と、第一の光照射の後に単一のパルス光を照射する第二の光照射を行い、情報取得部は、第一の光照射によって発生した音響波に基づいて得られた第一のデータと、前記第二の光照射によって発生した音響波に基づいて得られた第二のデータとの差分である第三のデータを取得し、前記第三のデータを用いて被検体内の特性情報を取得し、所定の時間は、被検体内にある所定の部位が、パルス光に起因して励起状態となってから、当該励起状態が緩和するまでの時間よりも短い時間である。【選択図】図１
