<p>In an electro-acoustic transducer 100 which is an oscillator device, a flat piezoelectric film 120 that moves expansively and contractively through the application of an electric field is disposed on at least one surface of a flat elastic member 110 in which a plurality of holes 111 penetrate a principal surface thereof. Since the stiffness of the elastic member 110 is adjusted by the holes 111, the stiffness impedance with respect to the piezoelectric film 120 can be matched optimally. Thus, it is possible to suppress the amount of vibration displacement and to complement the conversion efficiency of the piezoelectric film 120.</p>