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Phase Unwrapping of Reconstructed Holograms |
Pande Mitrev Section Microtechnique, EPFL |
Semester project
March-June 2002 |
Abstract
Digital Holograhy method permits to reconstruct the phase of an object
wave. Depending on the shape of the object, the reconstructed phase can
be wrapped. The aim of this semester project is the implementation and
the efficiency evaluation of a phase unwrapping algorithm. The algorithm
uses the least-squares principle of the phase unwrapp!
ing problem and the
processing is done in the Fourier domain. During this project, we implemented
two boundary conditions: periodic and mirror. Results obtained with the
mirror boundary conditions are better than those obtained with the periodic
ones. The congruence post-operation was also implemented and it improves
the unwrapped result when the input image contains some noise.
The Figure below shows the results obtained with the two boundary conditions.
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Wrapped images |
Periodic boundary conditions |
Mirror boundary conditions |
TO |
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T1 |
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T0 < T1
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