The fiber geometry of communication fibers and medical fibers are always standards to evaluate the quality of optical fibers. The measurement of fiber geometry with gray scale method is one of the commonly used measurement methods. It is also the proposed method in the national standard GB15972.20-2008. In this method, the fiber geometry is obtained by fitting the elliptical curve and fitting the circular curve in two steps, but the center of the two curves may not be coincided. Thus, there is a defect in the measurement principle in the method. The measurement of fiber geometry with gray scale method has a high requirement for cutting effects and lighting conditions. When measurement conditions change, it often leads to the instability of the measured data and brings errors. In this paper, we use the arbitrary elliptical function (non-standard ellipse) which is more suitable for the fiber end face, and only use this function fitting method to get the fiber geometry to fundamentally eliminate the principle defect caused by the inconsistent center fitting between the circle fitting and the ellipse fitting. At the same time, the requirement of measurement condition is reduced, because the specific value of image distribution grayscale is not needed when calculating each parameter. Experiments show that this method can effectively improve the stability and consistency of measurement results.
Measurement of optical fiber geometry with arbitrary ellipse curve fitting
First published at:May 01, 2019
1 General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China. Specifications for optical fibre test methods-part 20: measurement methods and test procedures for dimensions- fiber geometry: GB 15972.20–2008[S]. Beijing: Standards Press of China, 2008.
2 Chen L, Chen J B, Lu R H. Automatic measurement of optical fiber geometric parameters[J]. Acta Optica Sinica, 2001, 21(10): 1245–1248. DOI:10.3321/j.issn:0253-2239.2001.10.021
陈磊, 陈进榜, 陆润华.光纤几何参数的自动检测仪[J].光学学报, 2001, 21(10): 1245–1248. DOI:10.3321/j.issn:0253-2239.2001.10.021
3 Yin A E, Jiang Z X, Zhang Y L. Refracted near-field technique for the measurement of optical fiber refractive index profiles[J]. ActaOpticaSinica, 1989, 9(2): 181–185. DOI:10.3321/j.issn:0253-2239.1989.02.014
殷爱娥, 姜仲玄, 张一龙.光纤折射率剖面的折射近场法测量的研究[J].光学学报, 1989, 9(2): 181–185. DOI:10.3321/j.issn:0253-2239.1989.02.014
4 Gao Y C. Simulation of measuring the optical fiber refractive index profiles by refraction near-field method[D]. Harbin: Harbin Engineering University, 2012.
5 Sun H G, Chu J R, Zhong L S, et al. Measurement of refractive-index profile of plastic optical fibers[J]. OpticalFiber& Electric Cable, 2001(4): 12–16. DOI:10.3969/j.issn.1006-1908.2001.04.004
孙会刚, 储九荣, 钟力生, 等.塑料光纤折射率分布的测量方法[J].光纤与电缆及其应用技术, 2001(4): 12–16. DOI:10.3969/j.issn.1006-1908.2001.04.004
6 Jia H Z, Li Y L, Hu M L. Fabrication methods of fiber gratings[J]. LaserTechnology, 2001, 25(1): 23–26. DOI:10.3969/j.issn.1001-3806.2001.01.001
贾宏志, 李育林, 忽满利.光纤光栅的制作方法[J].激光技术, 2001, 25(1): 23–26. DOI:10.3969/j.issn.1001-3806.2001.01.001
7 Wu Z H. The research about measurement system of six-angle fiber geometrical dimension on the basis of CCD and image processing[D]. Taiyuan: Taiyuan University of Technology, 2006.
8 Ma L D. Research on effective mode area measurement of photonic crystal fiber[D]. Qinhuangdao: Yanshan University, 2016.
9 Hameed M F O, Obayya S S A. Modal analysis of a novel soft glass photonic crystal fiber with liquid crystal core[J]. JournalofLightwaveTechnology, 2012, 30(1): 96–102. DOI:10.1109/JLT.2011.2175436
10 Rosa L, Coscelli E, Poli F, et al. Thermal modeling of gain competition in Yb-doped large-mode-area photonic-crystal fiber amplifier[J]. OpticsExpress, 2015, 23(14): 18638–18644. DOI:10.1364/OE.23.018638
11 Yang Y. Research on detecting optical fiber geometric parameter based on machine vision[D]. Harbin: Harbin Engineering University, 2011.
12 Ling F C, Kang M, Lin X. Improved Canny edge detection algorithm[J]. ComputerScience, 2016, 43(8): 309–312. DOI:10.11896/j.issn.1002-137X.2016.8.063
凌凤彩, 康牧, 林晓.改进的Canny边缘检测算法[J].计算机科学, 2016, 43(8): 309–312. DOI:10.11896/j.issn.1002-137X.2016.8.063
13 Guo M, Hu L L, Zhao J T. Surface defect detection method of ceramic bowl based on Kirsch and Canny operator[J]. ActaOpticaSinica, 2016, 36(9): 0904001. DOI:10.3788/aos201636.0904001
郭萌, 胡辽林, 赵江涛.基于Kirsch和Canny算子的陶瓷碗表面缺陷检测方法[J].光学学报, 2016, 36(9): 0904001. DOI:10.3788/aos201636.0904001
14 Wang W H, Jiang M X, Zhao W D. Edge detection algorithm based on improved Canny operator[J]. ChinaSciencepaper, 2017, 12(8): 910–915. DOI:10.3969/j.issn.2095-2783.2017.08.013
王文豪, 姜明新, 赵文东.基于Canny算子改进的边缘检测算法[J].中国科技论文, 2017, 12(8): 910–915. DOI:10.3969/j.issn.2095-2783.2017.08.013
15 Wang W G, Wang S R, Xu Z F, et al. Optimal ellipse fitting algorithm of least square principle based on boundary[J]. ComputerTechnologyandDevelopment, 2013, 23(4): 67–70. DOI:10.3969/j.issn.1673-629X.2013.04.016
王万国, 王仕荣, 徐正飞, 等.基于边界的最小二乘椭圆拟合改进算法[J].计算机技术与发展, 2013, 23(4): 67–70. DOI:10.3969/j.issn.1673-629X.2013.04.016
16 Xiong F G, Li X, Han X. A method of ellipse fitting based on total least squares[J]. Microelectronics&Computer, 2017, 34(1): 102–105.
17 Cao J L, Li J F. Improved ellipse fitting algorithm based on Letts criterion[J]. JournalofComputerApplications, 2017, 37(1): 273–277. DOI:10.11772/j.issn.1001-9081.2017.01.0273
曹俊丽, 李居峰.基于莱特准则的椭圆拟合优化算法[J].计算机应用, 2017, 37(1): 273–277. DOI:10.11772/j.issn.1001-9081.2017.01.0273
18 Gander W, Golub G H, Strebel R. Least–squares fitting of circles and ellipses[J]. BIT Numerical Mathematics, 1994, 34(4): 558–578. DOI:10.1007/BF01934268
19 Mitchell D R G, Van den Berg J A. Development of an ellipse fitting method with which to analyse selected area electron diffraction patterns[J]. Ultramicroscopy, 2016, 160: 140–145. DOI:10.1016/j.ultramic.2015.10.009
20 He C C, Yang J, Song H Y, et al. Effect of cutting tool aging on the geometric size measurement of single mode fiber[J]. ModernTransmission, 2016(1): 56–61. DOI:10.3969/j.issn.1673-5137.2016.01.001
何晨程, 杨婧, 宋海燕, 等.切割刀老化对单模光纤几何尺寸检测结果的影响[J].现代传输, 2016(1): 56–61. DOI:10.3969/j.issn.1673-5137.2016.01.001
21 Liu W, Tang C H, Ma X M, et al. Measurement of geometric parameters of defective fiber ends[J]. StudyonOpticalCommunications, 2013, 39(6): 35–38. DOI:10.3969/j.issn.1005-8788.2013.06.011
刘为, 唐春晖, 马秀梅, 等.缺陷光纤端面几何参数的测量[J].光通信研究, 2013, 39(6): 35–38. DOI:10.3969/j.issn.1005-8788.2013.06.011
National Natural Science Foundation for Young Scientists of China (61605114)
Get Citation: Li Yiming, Zheng Gang, Tu Jiankun, et al. Measurement of optical fiber geometry with arbitrary ellipse curve fitting[J]. Opto-Electronic Engineering, 2019, 46(5): 180319.