Title :
Evaluating uncertainty of the mean diameter of silicon sphere by Spherical Harmonics
Author :
Zhang, Jitao ; Li, Yan ; Wu, Xuejian ; Zhang, Liqiong ; Liu, Zhen ; Luo, Zhiyong
Author_Institution :
Dept. of Precision Instrum. & Mechanology, Tsinghua Univ., Beijing, China
Abstract :
Considering the most accurate target of Avogadro project ever, the methods of estimating the uncertainty of average diameter by Spherical Harmonics (SH) are reevaluated, and the uncertainty component that can not be ignored is emphasized. Five thousand approximate spheres are generated to simulate the features of real sphere. It´s shown that, the estimated uncertainty of the average diameter based on the N-point mean method is incomplete when considering the features of the real sphere. Besides, increasing the number of sampling points can improve the uncertainty of the average diameter.
Keywords :
approximation theory; constants; diameter measurement; silicon; Avogadro project; N-point mean method; SH evaluation; mean diameter evaluating uncertainty; sampling points; silicon sphere; spherical harmonics; Bandwidth; Electromagnetic measurements; Equations; Instruments; Least squares approximation; Metrology; Optical interferometry; Sampling methods; Silicon; Uncertainty;
Conference_Titel :
Precision Electromagnetic Measurements (CPEM), 2010 Conference on
Conference_Location :
Daejeon
Print_ISBN :
978-1-4244-6795-2
DOI :
10.1109/CPEM.2010.5543574
