Xinyu TONG, Chuanqian PENG, Yumei HE, et al. Curve fitting algorithm for measurement data of long trace profiler[J]. Nuclear techniques, 2016, 39(8): 080102
DOI:
Xinyu TONG, Chuanqian PENG, Yumei HE, et al. Curve fitting algorithm for measurement data of long trace profiler[J]. Nuclear techniques, 2016, 39(8): 080102 DOI: 10.11889/j.0253-3219.2016.hjs.39.080102.
Curve fitting algorithm for measurement data of long trace profiler
The Long Trace Profiler (LTP) has been widely used to measure the profile of optical mirrors used in synchrotron radiation applications. The Root Mean Square (RMS) of profile error from fitted profile is used to evaluate the quality of mirror.
Purpose:
2
This study aims to find a better fitting algorithm for measurement data of LTP and minimize system errors generated by fitting.
Methods:
2
Least square method (LSM) based on the algebraic distance
LSM based on geometric distance
and genetic algorithm have been compared for simulation profiles of the measured data of LTP with different radii
noise intensities and postures.
Results:
2
Simulation results showed that fitting algorithm of least-squares orthogonal geometric distances had a good noise robustness
and insensitiveness to the mirror's postures.
Conclusion:
2
Least-squares orthogonal distances is the most suitable curve fitting algorithm for LTP
it provides references for the profile testing of optical mirrors at SSRF.
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references
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