Acoustic holograms of the single slit, the sound source and the cross aperture were obtained using two-phase-electrical reference method. The image were reconstructed numerically from the holograms, and amplitudes and phases of the propagated waves to the hologram aperture were fully reformed in the one dimensional case. The Rayleigh-Sommerfeld formula as the inverse transformation function was shown to be applicable under assumptions that the holograms should be obtained in the far field of the insonified objects and the distance from the hologram plane to the objects is greater than the wave-length. The noise effects on the holograms were classified by the on-off state of the scanner and the sound source, and their effects on the reconstructed image were discussed.