COMPUTER-AIDED EVALUATION OF INTERFEROGRAMS

A semi-automatic technique is presented for obtaining the density fiel d from interferograms provided by a Mach-Zehnder setup in infinite fri nge width adjustment using short exposure times. The algorithm relies on extracting the fringe edges from the original image and then number ing the resulting polygons according to their order of interference us ing a graphical editor. The density field is then interpolated between the polygons by calculating its value from the intensity in the origi nal interferogram. This results in highly accurate, high resolution sc alar data fields. The results may then be presented in a quasi three-d imensional form using a shading model.