Tomographic reconstruction of strongly refracting fields and its application to interferometric measurement of boundary layers.

An iterative algorithm for tomographic reconstruction of refractive-index fields from measured values of path integrals along rays which have been bent by refraction is presented. The behavior of the algorithm is studied by applying it to path length data obtained by computer simulation of experiments in which holographic or Mach-Zehnder interferograms of the field are recorded for several different viewing directions. A special form of the algorithm is also used to measure concentration profiles in the boundary layer formed at the cathode of an electrolytic cell containing ZnCl(2). The Appendix contains a discussion of series expansion techniques for reconstructing object fields from measured values of line integrals through the field.