Physical limitations on spatial resolution in electrical capacitance tomography
Physical limitations on spatial resolution in electrical capacitance tomography
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DOI：
10.1088/0957-0233/26/12/125105
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发表时间：
2015-11
影响因子：
2.4
通讯作者：
J. Lucas;C. Margo;Y. Oussar;S. Holé
中科院分区：
文献类型：
--
作者：
J. Lucas;C. Margo;Y. Oussar;S. Holé
电容层析成像（ECT）是一种通过电极提供介质中介电常数分布的成像技术。对于任何成像系统，可达空间分辨率都是一个关键参数。本文分析了ECT传感器空间分辨率的物理限制，包括物体位置的精度和对任何传感器几何形状的两个近距离物体的区分能力。特别研究了圆柱形传感器，并以方形传感器为例，说明了如何将计算应用于任何其他几何形状。在圆柱形几何中，电极之间的间隙为50%是一个很好的折衷，增加电极的数量可以提高电极附近的空间分辨率，但会降低中心的空间分辨率。采用3个或4个电极可获得传感器中心的最佳空间分辨率。在方形几何结构中，当边角处有电极时，空间分辨率分布较好。
Electrical capacitance tomography (ECT) is an imaging technique providing the distribution of permittivity in a medium by means of electrodes. As for any imaging systems, the accessible spatial resolution is a key parameter. In this paper the physical limitations on the spatial resolution of ECT sensors are analysed in terms of the accuracy of an object’s position and of the ability to distinguish between two close objects for any sensor geometry. Cylindrical geometry sensors are particularly studied and the example of a square geometry sensor is used to show how to apply the calculations to any other geometries. In cylindrical geometries, it is shown that a 50% gap between electrodes is a good compromise and that increasing the number of electrodes improves the spatial resolution near the electrodes but decreases the spatial resolution in the centre. The best spatial resolution at the centre of the sensor is obtained with 3 or 4 electrodes. In the square geometry studied, it is shown that a better distribution of the spatial resolution is obtained when there are electrodes in the corners.