The scope and limitations of three-dimensional holography of phase objects

In the three-dimensional holography of phase objects, scatter screens have been used to provide diffuse illumination. In the reconstruction process a diaphragm is used to select a particular angle or position of view. The paper shows that there are upper and lower limits to the size of the diaphragm, determined by the optical path variations within the object. These limits are not necessarily compatible with one another. Thus the scatter screen technique is shown to have limitations. An alternative is simply to use an array of parallel beams separated by discrete angular intervals. The advantage of continuous variation of viewing angle is lost but the resistrictions on the type of object are less severe. In addition the reconstructions may take the form of schlieren or shadow photographs as well as interferograms.