PROBLEM TO BE SOLVED: To provide a subject information acquisition apparatus in which the effect of prelasing is reduced.SOLUTION: The subject information acquisition apparatus comprises: a laser resonator including two reflectors and a Q switch arranged therebetween and an excitation part for optically exciting a laser medium. The subject information acquisition apparatus also comprises: a detection part for detecting the intensity of the laser beam in a range narrower than the range in which the intensities of the laser beam are distributed, the intensities being on a plane perpendicular to the travel direction of the laser beam output from one of the two reflectors and a determination part for determining whether or not prelasing light is included in the laser beam, on the basis of the detection result of the detection part. The subject information acquisition apparatus further comprises: a projection part for projecting the laser beam onto a subject and a reception part for receiving acoustic waves transmitted from the subject based on the projection of the laser beam. The subject information acquisition apparatus furthermore comprises: an acquisition part for acquiring information related to the subject on the basis of the reception result of the reception part and a control part arranged in the prestage of the detection part, for controlling the output of the laser beam on the basis of the determination result of the determination part.COPYRIGHT: (C)2016,JPO&INPIT【課題】プレレージングによる影響を低減した被検体情報取得装置を提供する。【解決手段】二つの反射体と、二つの反射体の間に設けられるQスイッチとを含むレーザー共振器と、レーザー媒質を光励起する励起部とを備える。さらに、一方の反射体から出力するレーザー光の進行方向に垂直な面におけるレーザー光の強度が分布する範囲よりも狭い範囲で前記レーザー光の強度を検出する検出部と、検出部の検出結果に基づいてレーザー光にプレレージング光が含まれているか否かを判定する判定部とを備える。さらに、レーザー光を被検体に照射する照射部と、レーザー光の照射に基づいて被検体から伝播する音響波を受信する受信部とを備える。さらに、受信部の受信結果に基づいて被検体についての情報を取得する取得部と、検出部の前段に設けられ、判定部の判定結果に基づいてレーザー光の出力を制御する制御部とを備える。【選択図】図1A
