Extraction of 3D axial features in programmable point-source digital in-line holographic microscope with spherical reference field

This paper presents a technique of extracting the three-dimensional axial information in a digital in-line holographic microscope by using digital micromirror devices to define the point source of the spherical reference field. Translation of the ON-state mirror element changes the spatial location of the point source and consequently generates a sequence of translated holograms with different projections of the object. A demonstration of this capability using microspheres deposited on both side of microscope slide shows the possibility of discriminating between features at different planes through the object.