Automatic Determination Method of the Modulation of Duplex Wire Image Quality Indicator
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摘要: 双线型像质计常用于测量射线检测图像的不清晰度,或测量数字射线探测器的基本空间分辨率。在实际应用中,用人工方法对双线型像质计调制度的定量计算比较繁琐。为解决这一问题,提出了一种双线型像质计调制度的自动定量方法。首先,将双线型像质计的灰度数据进行分段和归一化处理,并根据起始、终止点对应的灰度值进行数据甄别,决定是否进行下一步分析;然后,设计相应的算法寻找线对的沉降值,转换后即得到线对的调制度。所提出的自动定量方法,针对射线检测试验中的双线型像质计的灰度曲线进行一次处理,即可便捷、可靠地定量出各个线对的调制度。Abstract: Duplex wire image quality indicator (IQI) is often used to measure unsharpness in radiography, or to determine basic resolution of an X-ray digital detector. However, manual determination of modulation of the IQI is rather bothersome. So, an automatic method was put forward. Firstly, data from IQI was cut to segments by certain width from beginning to end, and each segment was normalized. All the segments were discriminated according to gray values of beginning position and end position, and qualified segments need to be processed further. Secondly, dip position in duplex wire curve was searched according to an algorithm, and its position value in the segmented curve can be used to determine the modulation. The proposed method is able to determine modulation of each duplex wire quickly and reliably through processing just a time.
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Keywords:
- Duplex wire IQI /
- Modulation /
- Measurement /
- Automatic
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[1] CRISCUOLO E L. Evaluation of a new radiographic image quality indicator[R].Fort Belvoir:Defence Technical Information Center,1968.
[2] 郑世才.双丝像质计介绍[J].无损探伤,2007,31(3):32-35. [3] HARRISON R M. Digital radiography[J]. Physics in Medicine and Biology,1988,33(7):751-784.
[4] 郑世才.数字射线检测技术专题(一)——概述[J].无损检测,2014,36(7):11-13. [5] 郑世才.数字射线检测技术专题(六)——数字射线检测技术标准介绍[J].无损检测,2014,36(12):46-51. [6] 梁丽红.数字射线检测实用指导(三)——射线数字成像的像质评价[J].无损检测,2012,34(6):44-46. [7] HALMSHAW R. The effect of focal spot size in industrial radiography[J].Insight,1992,34(8):389-394.
[8] BAVENDIEK K, HEIKE U, MEADE W D,et al. New digital radiography procedure exceeds film sensitivity considerably in aerospace applications[C]//Procedings of 9th ECNDT. Berlin:German Society for Non-destructive Testing, 2006.
[9] ZSCHERPEL U, EWERT U, JECHOW M. New requirements for digital radiographic testing of welds according to iso standards[C]//Procedings of 39th annual review of progress in quantitative nondestructive evaluation.Baltimore:American Institute of Physics,2013.
[10] 王建华,孟令钊,谢茂博,等.高清平板探测器性能测试和应用[C]//射线检测技术及装备高峰论坛论文集.丹东:中国机械工程学会无损检测分会射线专业委员会,2015. [11] 孙朝明,汤光平,李强,等.X射线源焦点尺寸的测试与对比分析[J]. 核技术,2015,38(11):1102021-7. [12] KAFTANDJIAN V, ZHU Y M, ROZIERE G,et al. A comparison of the ball, wire, edge, and bar/space pattern techniques for modulation transfer function measurements of linear X-ray detectors[J]. Journal of X-Ray Science and Technology, 1996,6:205-221.
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