Date of Award
Thesis - Restricted
Master of Science (MS)
The analysis of holointerferograms is complicated by the fact that holointerferograms by themselves do not contain enough information to determine the sign of any phase changes over their area. Different techniques have been proposed to enable the sign of the phase to be monitored, such as the introduction of a carrier fringe pattern, the use of sandwich holograms, and the use of a mutual phase shift between two successive holointerferograms. This thesis will attempt to solve some of the problems of the last-mentioned technique, discuss its advantages and disadvantages compared to the others, and apply the method to a practical case. The basic idea of this technique is that after taking a picture of a holointerferogram, a phase shift will be introduced into the reconstruction beam, and a second picture will be taken of the modified holointerferogram. By applying band-pass filtering techniques to two-dimensional Fourier transforms of the images, the sign and magnitude of phase change over the entire area of the holointerferograms can be obtained.
Guo, Dan, "Automated Evaluation of Holographic Interferograms by Combining Fourier Transform and Phase Shift Techniques" (1989). Master's Theses (1922-2009) Access restricted to Marquette Campus. 2233.