测量型显微CT系统的定值方法

发布时间：2018-06-06 02:00

本文选题：显微CT标准器 + 光耦探测器　；参考：《天津大学》2016年硕士论文

【摘要】：测量型CT系统作为一种新型的坐标测量技术在近年来逐步受到人们的认可,国内外的诸多科研机构对其也在持续进行相关的研究,并取得了一定成果。由于测量型CT系统多具有X射线源、机械运动系统、平板探测器、扫描数据重建模块等多种组成部分,这就导致了其测量误差来源极为复杂。显微CT在平板探测器的基础上,新增了光耦探测器单元,提高了CT系统的空间分辨力,同时扩大了CT系统的测量范围,使其能够对尺寸从微米量级到百微米量级的样品进行几何量测量。但由于其包含了闪烁体、显微物镜、管镜及CCD等组件,结构相较于平板探测器更为复杂,使得测量误差来源范围进一步扩大。这使得其测量的准确性的提升以及测量不确定度的量值溯源变得尤为困难。本文针对显微CT的计量特性制订了一套校准方案,设计了可用于校准显微CT探测形状误差及探测尺寸误差的微球标准器以及可用于校准显微CT探测形状误差及长度测量误差的微型球板标准器和微型孔板标准器,使用微纳坐标测量机、圆度仪与计量型扫描电子显微镜对其进行定值,然后用其对显微CT的几何量测量误差进行校准,并对校准结果进行了初步的不确定度来源分析及合成标准不确定度的计算。最后,对使用新的材料、新的方法在微观领域研制更新型的微型标准器的工作进行了合理展望。
[Abstract]:As a new type of coordinate measurement technology, measuring CT system has been gradually recognized by people in recent years, and many scientific research institutions at home and abroad are continuing to study it, and have achieved certain results. The measuring CT system has many components, such as X-ray source, mechanical motion system, flat panel detector, scan data reconstruction module and so on, which makes the source of measurement error extremely complex. On the basis of flat panel detector, micro-CT has added photocoupling detector unit, which improves the spatial resolution of CT system and expands the measurement range of CT system. It enables geometric measurements of samples ranging in size from micron to 100 microns. However, because of its scintillator, micro objective lens, tube mirror and CCD components, the structure is more complex than the flat panel detector, which makes the source range of measurement error further expanded. This makes it difficult to improve the accuracy of measurement and trace the source of uncertainty. In this paper, a calibration scheme is developed for the metrological characteristics of microCT. The microsphere standardiser, which can be used to calibrate the shape error and dimension error of microCT detection, and the microsphere plate standardiser and micro-hole plate standardiser, which can be used to calibrate the shape error and length measurement error of microCT detection, are designed. The micro / nano coordinate measuring machine, roundness instrument and metrological scanning electron microscope are used to calibrate the geometric error of micro CT. The source analysis of the calibration results and the calculation of the synthetic standard uncertainty are carried out. Finally, the work of developing a new type of micro standard device in the micro field with new materials and new methods is prospected.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH721

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