摘要
电子束莫尔条纹的强度、角度、距离和线宽等特征参数是分析短磁聚焦分幅变像管成像性能,探讨像管空间分辨性能提升的重要信息.为提升莫尔条纹的提取和参数分析效率,采用巴特沃斯低通滤波器、阈值选取算法和区域匹配算法,通过Matlab的GUI界面对条纹提取和参数分析,实现了智能操作和批处理.研究结果显示,电子束莫尔条纹信息的提取时间为~12 s,莫尔条纹倾斜角度和间距的提取结果与人工操作的差异分别仅为~1.75%和~3.13%.该方法可实现条纹信息的批处理,有效提升海量信息中电子束莫尔条纹的提取及其参数分析效率,为研究短磁聚焦分幅变像管的空间分辨性能提供可靠数据.
The intensity,angle,interval,and linewidth of the electron beam moiré fringe are important characteristic parameters for analyzing the imaging performance of the short magnetic-focused framing tube and exploring the method of improving the spatial resolution of the tube. In order to improve the efficiency of the extraction and parameter analysis of the moiré fringe, Butterworth's low-pass filter, threshold selection algorithm and region matching algorithm are integrated in the Matlab GUI window for fringe extraction and parameter analysis,which enables an intelligent batch processing. The experimental results show that the extraction time of the moiré fringe information is about 12 s,and the differences between the extraction results of the angle and interval of the moiréfringes and the corresponding manual operation results are only about 1. 75% and 3. 13%,respectively. This method can realize the batch processing of the fringe information,effectively improve the extraction of the electron beam moiré fringes and the efficiency of parameter analysis in mass information,and provide reliable data for studying the spatial resolution characteristic of the short magnetic-focused framing tube.
引文
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