Holographic image of a point source in the presence of misalignment

The imaging of a point source by high numerical aperture holograms was studied theoretically and experimentally in the presence of aberrations caused by inaccurate adjustment of the plane reference and plane reconstructing waves or by inaccurate positioning of the hologram. The accuracy requirement is defined by the angular resolution allowed by an aperture equal to the hologram size. Any deviation from this limit leads to deformation of the point transfer function defined by the unavoidable diffraction. For coarse mismatch (>10(-3) rad for the actual case), clearly demonstrable geometrical-type aberrations occur; for smaller angles, appreciable broadening of the diffraction pattern and rapid fall of the Strehl ratio diminish the applicability of the holographic method. The calculations and the photographic and photometric measurements are in good agreement.