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16:11
Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Interferometer errors due to the presence of fringes
Applied Optics
|December 15, 2010
Summary
Phase-shifting interferometry struggles with accuracy when analyzing complex interferograms with many fringes. Using a defocused spherical wave-front revealed measurement degradation with different reference objectives.
Area of Science:
- Optical metrology
- Interferometry
Background:
- Phase-shifting interferometry (PSI) is a technique for analyzing interferograms.
- Measurement accuracy in PSI can be limited by factors such as fringe density.
Purpose of the Study:
- To investigate the impact of fringe count on measurement accuracy in phase-shifting interferometry.
- To demonstrate fringe-induced degradation using a specific optical setup.
Main Methods:
- Utilized phase-shifting interferometry.
- Employed a defocused spherical wave-front as the test object.
- Evaluated performance with multiple transmission reference objectives.
Main Results:
- Observed a reduction in measurement accuracy as the number of fringes increased.
- Demonstrated this degradation across various reference objectives.
Conclusions:
- The number of fringes significantly affects the accuracy of phase-shifting interferometry.
- Careful selection of reference objectives is crucial for maintaining accuracy with complex interferograms.
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