Abstract：The components of 2m Length Comparator are described.The principle of line space dynamic measurement with photoelectric microscope and laser interferometer is analyzed.The methods for improving the accuracy of line positioning and line space measurement are studied,and the methods for automatically and synchronously processing of line signal and interference signal with high speed are studied also.The signal processing system is based on integrate circuit FPGA and computer techniques.The experiment,according to Verification Regulation JJG 331-1994 (China):the interference length comparator,was performed for measurement of standard metal line scale.The result shows that the best standard deviation of position for line with good quality is less than 10nm,and the measurement uncertainty analysis for the line space shows that,when measuring high quality line scale,the expanded measurement uncertainty U=（20+40L）nm,k=2.
高宏堂,叶孝佑,邹玲丁,孙双花,沈雪萍,甘晓川,常海涛,王健. 2m比长仪纳米级精度线间距测量系统的研究[J]. 计量学报, 2012, 33(2): 97-103.
GAO Hong-tang,YE Xiao-you,ZOU Ling-ding,SUN Shuang-hua,SHEN Xue-ping, GAN Xiao-chuan,CHANG Hai-tao,WANG Jian. Study of Automatic Measurement System for Line Space Measurement with Nanometer Accuracy in 2m Length Comparator. Acta Metrologica Sinica, 2012, 33(2): 97-103.
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2012, Vol. 33 
