An apparatus includes a receiving unit configured to receive a photoacoustic wave that is generated when an object is illuminated with light and to output a time-series received signal, and a processing unit configured to acquire object information by performing a reconstruction process on the time-series received signal using a specific speed of sound, wherein in the reconstruction process, the processing unit converts a reception time of the time-series received signal to a reception time normalized with respect to the specific speed of sound.
