Tilted objects EFI extracted at once by 3D output of the angular spectrum method

• 3D full stack of propagated images at once.
• Quasi-automatic method for the EFI extraction.
• Method validation through Tamura index.
• Additional tests to compare our results with another technique.

Since many optical imaging systems suffer from a limited depth of focus, three-dimensional (3D) objects, or even flat objects tilted with respect to the optical axis, are imaged with only a portion of them in focus. Typically, to overcome this problem, in-focus areas are extracted from different images taken at different depths. The in-focus regions are thus merged together to build the extended focus image (EFI). In this work, we propose a quasi-automatic method for the EFI construction of tilted objects, extracted at once by 3D output of the Angular Spectrum Method (ASM) from a single digitally recorded hologram. Results show that our method can be effectively used for the correction of the anamorphism due to the reconstruction on a tilted plane with respect to the hologram one.