Development of Digital Holographic Microscopy by reflection for analysis of surface

Abstract

A methodology based on the DHM of reflection using a Michelson micro interferometer scheme is used here for dimensional controlling objects and for determining the surface profile of steel samples. To reconstruct phase contrast distribution images, numerical techniques are used that enable Digital Holographic Microscopy to suppress zero order, pixel resolution control, optical phase unwrapping, intensity and phase mapping, filter and compensation of optical system aberrations that influence the quality of the image. The numerical reconstruction of the images is conducted using the double propagation algorithm. The program used allows quantitative measurements of the dimensions of objects and the surface profile of the samples, as well as the 3D representation of the reconstructed phase image. The results from DHM are validated by comparison with those from a non-contact 3D profilometer model CCI-MP. Keywords: Digital holography, Digital Holographic Microscopy, Surface profile