Nuclear Techniques ›› 2016, Vol. 39 ›› Issue (8): 80102-080102.doi: 10.11889/j.0253-3219.2016.hjs.39.080102


Curve fitting algorithm for measurement data of long trace profiler

TONG Xinyu1,2, PENG Chuanqian1,2,3, HE Yumei1, WANG Jie1   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangjiang Campus, Shanghai 201204, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Chongqing University of Technology, Chongqing 400050, China
  • Received:2016-03-11 Revised:2016-04-22 Online:2016-08-10 Published:2016-08-15
  • About author:TONG Xinyu, male, born in 1991, graduated from Zhengzhou University in 2012, master student, focusing on X-ray optical technology
  • Supported by:

    Supported by National Natural Science Foundation of China (No.11179005)


Background: 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: This study aims to find a better fitting algorithm for measurement data of LTP and minimize system errors generated by fitting. Methods: 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: 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: 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.

Key words: LTP, Curve fitting algorithm, Synchrotron radiation, Surface quality

CLC Number: 

  • TL99