The present invention relates to an acousto-optic device capable of extending the frequency band of SAWs being able to be generated by it, the acousto-optic device comprising: a light propagation unit for propagating light; a surface acoustic wave propagation unit capable of propagating a surface acoustic wave causing interaction with light which propagates in the light propagation unit; and a transducer electrode unit provided with a plurality of electrodes configured so as to correspond to a frequency band to be generated as the surface acoustic wave which propagates in the surface acoustic wave propagation unit.