PROBLEM TO BE SOLVED: To provide a subject information acquisition device capable of accurately acquiring a photoacoustic signal generated in a subject.SOLUTION: A subject information acquisition device comprises: a light irradiation unit which irradiates a subject with light, and can change an emission direction of the light a scanning mechanism for moving the light irradiation unit along a first axis a probe for receiving a photoacoustic wave generated due to the light emitted to the subject a processing part for generating characteristic information of the subject from the acoustic wave received by the probe and a control unit for controlling the position of the light irradiation unit on the first axis and the emission direction of the light emitted from the light irradiation unit. The control unit determines the emission direction of the light emitted from the light irradiation unit on the basis of the position of the light irradiation unit on the first axis.SELECTED DRAWING: Figure 1
