A backscattering formula for a single transducer geometry is derived. It expresses the output voltage of the transducer in terms of the angular spectra of scalar and vector acoustic potentials on a plane. The formulation is suitable for acoustic problems involving wide angular spectrum beams. The derived formula gives a simple expression for the problem of a circular transducer facing a plane reflector. The output voltage of a transducer receiving the backscattered waves from an arbitrary size spherical flaw is also presented.