The ordinary differential equation (ODE) and partial differential equation (PDE) image-
processing methods have been applied to reduce noise and enhance the contrast of
electronic speckle pattern interferometry fringe patterns. We
evaluate the performance of a few representative PDE denoising models
quantitatively with two parameters called image fidelity and speckle index, and then
we choose a good denoising model. Combining this denoising model with the ODE
enhancement method, we make it possible to perform contrast enhancement and
denoising simultaneously. Second, we introduce the δ-mollification method to smooth the
unwrapped phase map. Finally, based on PDE image processing, δ mollification and
some traditional techniques, an approach of phase extraction from a single fringe
pattern is tested for computer-simulated and experimentally obtained fringe patterns.
The method works well under a high noise level and limited visibility and can extract
accurate phase values.
© 2006 Optical Society of America
Equations on this page are rendered with MathJax. Learn more.