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Abstract

The development of a tomographic reconstruction system for use with limited viewing angle data is described in this thesis. It covers the development of novel tomographic reconstruction software, the construction of a practical tomography system, and the testing of the system on real data.

The aim of this work was to produce a system which would allow the reconstruction in a computer of three dimensional density fields that had been recorded using holographic interferometry, from two dimensional views of the holograms. By their nature holograms have a restricted range of directions over which they may be viewed, whereas tomography usually relies on taking measurements about a wide range of views. Hence it was necessary to devise a means to overcome the loss of resolution that occurs in reconstructions when the angle of view is limited, as was the case with the holograms we used. This resulted in the principal novel development of this work, namely the use of a direct 3-D projection scheme in combination with an iterative reconstruction method using the Multiplicative Algebraic Reconstruction Technique algorithms. The application of this approach to data from real situations was also novel. The software for the 3-D projection scheme was designed to allow the flexible use of views from different directions to facilitate it's application to a variety of experimental configurations. It's performance when tested on model data is described, with the results showing the advantage of a direct 3-D reconstruction approach over the conventional 2-D slice approach in the case of limited viewing angles. The conclusion is drawn that a new practical method of extracting full field data from holographic interferograms has been demonstrated. Further, because of its generality it is applicable to other whole field optical recording systems.

Publication Type:	Thesis (Doctoral)
Subjects:	Q Science > QA Mathematics > QA76 Computer software T Technology > TJ Mechanical engineering and machinery
Departments:	School of Science & Technology > Engineering > Mechanical Engineering & Aeronautics School of Science & Technology > School of Science & Technology Doctoral Theses Doctoral Theses

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