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Two-dimensional surface profile imaging technique based on a double-grating frequency shifter.

Kaiwei Wang·Lijiang Zeng
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Abstract

A two-dimensional surface profile imaging technique that uses a low-coherence heterodyne interferometer is proposed. A double-grating frequency shifter was used in a tandem interferometer to provide the achromatic frequency shift for low-coherence light. A chopper, together with a processing circuit, was implemented to modulate the interference fringes. The surface profile was measured from the interference fringes taken by a CCD camera using a five-step method. The uncertainty in the displacement measurement is 0.34 microm for a displacement range of 43 microm. The surface profile of a glass sample with low effective reflectivity was acquired.

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AlgorithmsImage EnhancementImage Interpretation, Computer-AssistedImaging, Three-DimensionalInformation Storage and RetrievalInterferometryRefractometryEvaluation StudyJournal Article

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Kaiwei Wang, Lijiang Zeng. 2005-08-01. Two-dimensional surface profile imaging technique based on a double-grating frequency shifter.. https://doi.org/10.1364/ao.44.004625

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