摘要
研究了一种基于F-P标准具的透射物镜焦距测量新方法。单色光经F-P标准具后产生的系列圆锥光束作为测量的标准光束,系列圆锥光束圆锥角能从有溯源性的小数重合法准确定出,具备自校准特性。该标准光束通过待测物镜在焦平面处成像为规律已知的同心圆环,由同心圆环计算获得透射物镜焦距值。理论推导了透射物镜焦距测量模型;搭建了测量实验装置,以汞灯绿光作为光源,采用面阵器件实现同心圆环数据采集;重点采用虚拟像元内插与细分技术,结合圆半径回归方法对测量数据进行处理。实验中,结合汞灯两条黄光谱线,用小数重合法确定F-P标准具间隔d,用以焦距的溯源;详细分析了焦距测量不确定度分量并进行了不确定度的计算合成。实验获得,用面阵虚拟像元间距w＇作单位的透镜焦距测量结果的相对扩展不确定度为0.031%。讨论了测量实验改进与像元间距w定度的方案设计,可望将焦距值的相对扩展不确定度降低到0.020%以下。
In this paper,a new method for measuring focal length of transmission objective lens based on F-P standard is studied. The conical beams produced by monochromatic light transferring through a F-P etalon isadoptedas the standard light beams for measurement.The cone angles of the conical beams can be determined from the excess fraction methodwhich makes the measurement calibration itself.The standard light beams transfer through the transmission objective lens to create the concentric ringsat the focal planeunder the known law. Then,the focal length of the objective lens can be calculated by the concentric rings. The theoretical measurementmodel for the focal length of the transmission objective lens is deduced. Theexperimental test-bedis set up and the green spectral line of a mercury lamp is adopted as the light source. The concentric ringsare acquired by the plane array photoelectric device. The virtual pixel interpolation,subdivision technique and the circle radius regression method are employed to process the image data. In the experiment,the F-P standard interval dis determined by the excess fraction method with other two yellow spectral lines of the mercury lamp. The uncertainty component of focal length measurement is calculatedin detail. Experimental results show that the relative expanded uncertainty of the objective lens is 0. 031% by using the measurement unit of w＇（the virtual pixel distance of the plane array device）. The improvement of the experiments and the calibration process design of w are is also discussed. It is expected that the relative expansion uncertainty of the focal length can be reduced 0. 020% at least.
作者
沈小燕
孙志鹏
胡佳成
李罡
朱鹤年
Shen Xiaoyan;Sun Zhipeng;Hu Jiachengl;Li Gang;Zhu Henian(College of Metrology ＆ Measurement Engineering,China Jiliang University,Hangzhou 310018,China;Department of Physics,Tsinghua University,Beijing 100084,China)
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2018年第5期1-8,共8页
Chinese Journal of Scientific Instrument
基金
国家重点研发计划专项(2016YFF0200602)
国家自然科学基金国基金(51504229,51775529)
国家重大科学仪器开发专项(2016YFF0100505)
浙江省公益性技术应用研究计划(2015C33052)项目资助
关键词
焦距测量
F-P标准具
虚拟像元细分
溯源
圆半径回归
focal length measurement
F-P etalon
virtual pixel subdivision
trace to the source
circleradius regression
