Comparison of methods of suppression of undesired diffraction orders at numerical reconstruction of digital Fresnel holograms

摘要

Main information limitation of digital holograms is quantity of pixels. Necessity of spatial separation of informative diffraction order from undesired diffraction orders leads to additional reduction of quantity of resolved elements in reconstructed object. Eight methods of numerical suppression of undesired diffraction orders were compared. Under numerical testing using computer generated Fresnel holograms it was found that good quality of reconstructed images is provided by five out of eight methods. Digital Fresnel holograms were recorded and used for further methods comparison. Selection of field of frequencies zeroing method showed best results. Slightly worse results demonstrated median and Gauss filtering methods.