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12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Polynomial fitting of interferograms with Gaussian errors on fringe coordinates. 1: Computer simulations.
Applied Optics
|October 14, 2010
Summary
Polynomial fitting to interferometric data can bias optical path difference estimates. Seidel aberration acceptance increases with noise but decreases with more fringes.
Area of Science:
- Optical engineering
- Metrology
Background:
- Twyman-Green interferometry is a key technique for optical testing.
- Polynomial fitting is commonly used to analyze interferometric data.
Purpose of the Study:
- To investigate the impact of polynomial fitting on optical path difference (OPD) estimation in Twyman-Green interferograms.
- To analyze the influence of noise and fringe count on Seidel aberration coefficients.
Main Methods:
- Simulations of ideal Twyman-Green interferograms with straight, equally spaced fringes and x-tilt.
- Application of polynomial fitting to simulated interferometric data.
- Analysis of fitting coefficient bias and Seidel aberration acceptance.
Main Results:
- Polynomial fitting introduced bias in optical path difference coefficient estimation.
- The acceptance of Seidel aberrations increased with higher noise levels.
- Increasing the number of fringes reduced the acceptance of Seidel aberrations.
Conclusions:
- Care must be taken when using polynomial fitting for OPD analysis in interferometry.
- Noise levels significantly affect the reliability of Seidel aberration analysis from interferometric data.
- A higher number of fringes improves the accuracy of aberration analysis.
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