A photoacoustic apparatus includes a light irradiation unit configured to irradiate a first irradiation region of a subject with first intensity modulated light corresponding to a first coding sequence and to irradiate a second irradiation region of the subject with second intensity modulated light corresponding to a second coding sequence, a reception unit configured to receive photoacoustic waves generated when the subject is irradiated with the first and the second intensity modulated light and output a first signal, and a processing unit configured to perform decoding processing on the first signal based on information on the first and the second coding sequences to acquire a first decoded signal corresponding to the first irradiation region or a second decoded signal corresponding to the second irradiation region.
