PROBLEM TO BE SOLVED: To more accurately grasp a change in the concentration of components in a human body by a photoacoustic method. SOLUTION: A measurement unit 103 is worn by a person to be measured and measures acceleration in time series, and a body movement calculation unit 104 indicates a body size of the movement of the person to be measured from the acceleration measured by the measurement unit 103. The magnitude of the movement is calculated, the singular point extraction unit 105 extracts the time point when the magnitude of the body movement calculated by the body movement calculation unit 104 exceeds the threshold, and the matching unit 106 causes the singular point extraction unit 105. The changes in the photoacoustic signal before and after the extracted singular point are matched. [Selection diagram]【課題】光音響法による人体内の成分濃度の変化を、より正確に把握する。【解決手段】測定部１０３は、被測定者に装着されて加速度を時系列に測定し、体動算出部１０４が、測定部１０３が測定した加速度より被測定者の動作の大きさを示す体動の大きさを求め、特異点抽出部１０５が、体動算出部１０４が求めた体動の大きさが閾値を超えた時点を特異点として抽出し、整合部１０６が、特異点抽出部１０５が抽出した特異点の前後の光音響信号の変化を整合させる。【選択図】 図１
