Many algorithms and techniques exist for extracting fringe contour information from a greylevel interferometric image. However, when the background of the interferogram is cluttered and mottled, the fringe pattern can be indistinguishable from the grey level variations of the background. Automated fringe analysis can be difficult, if not impossible in such cases. This paper presents an algorithm which effectively eliminates background variations, extracts the fringe pattern and normalizes the fringe modulation. The algorithm is simple and ideally suited for implementation with current digital signal processing technology. In this paper we present theoretical background and examples with real data.
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© 1992 Laser Institute of America.
1992
Laser Institute of America
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