Noise-immune method for locating wrap regions in phase-step interferometry.
A method is presented that can be applied to phase-step interferometry to locate the regions within which integral multiples of pi should be added to the wrapped phase that results from arctangent calculations. Unlike previous methods, this one is immune to the noise-related errors that confuse simple phase-unwrap schemes. It makes use of the fact that the noise-related errors occur at fixed locations in the phase map, whereas the location of the wrap regions depends on the way in which the arctangent is calculated.
Stetson
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