Three-wavelength combination source for white-light interferometry

A three-wavelength combination source in white-light interferometry (WLI) is used to simplify the central fringe identification. It is found that, by using this technique, the minimum signal-to-noise ratio required by the system to identify the central fringe position can be reduced when compared with the use of two-wavelength combination sources. This technique is simple and effective and has potential uses in coherence-multiplexed interferometric sensor systems.<
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