DIGITAL INTERFEROMETRIC RECONSTRUCTION OF THE OBJECT WAVE FROM OFF-AXIS ELECTRON HOLOGRAMS

A digital method is presented which leads to an interferometric reconstruction of the object wave function. The reconstruction procedure consists of three steps: (1) Filtering of the hologram by employing the first-order sidebands of its Fourier transform. (2) Digital superposition of the hologram with an adapted sinusoidal fringe system in order to obtain fringes with prespecified orientation and fringe distance in the reconstruction. (3) Fourier transformation of the superposed hologram and utilization of the laterally shifted sidebands of interest. The theoretical background of the method is given and experimental results are presented.