Reconstruction of Inhomogeneous Scattering Objects from Holograms

Abstract

An experiment is reported in which the one-dimensional scattering potential along a line through a semitransparent bar with nonuniform index of refraction is determined from holographic measurements of scattered monochromatic light waves. The experiment is performed using an inhomogeneous bar for the first time in order to test quantitatively a recently developed inverse scattering theory. This theory suggests a method by which the three-dimensional structure of a semitransparent, weakly scattering object can be determined by means of light scattering experiments. The structural data obtained in this experiment agree with known object parameters to within errors of the order of a few percent. In addition, a problem that occurred in earlier experiments concerning the presence of an unwanted background is analyzed. A method for removing the background is described, which is employed in the present experiment and is applicable for use with all objects that scatter light only into directions that make small angles with the direction of incidence.