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Detection and Visualization of Defects in 3D Unstructured Models of Nematic Liquid Crystals
September-October 2006 (vol. 12 no. 5)
pp. 1045-1052
A method for the semi-automatic detection and visualization of defects in models of nematic liquid crystals (NLCs) is introduced; this method is suitable for unstructured models, a previously unsolved problem. The detected defects---also known as \emph{disclinations}---are regions were the alignment of the liquid crystal rapidly changes over space; these defects play a large role in the physical behavior of the NLC substrate. Defect detection is based upon a measure of total angular change of crystal orientation (the \emph{director}) over a node neighborhood via the use of a nearest neighbor path. Visualizations based upon the detection algorithm clearly identifies complete defect regions as opposed to incomplete visual descriptions provided by cutting-plane and isosurface approaches. The introduced techniques are currently in use by scientists studying the dynamics of defect change.
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Index Terms:
scientific visualization, disclination, nematic liquid crystal, defects, unstructured grid, feature extraction
Citation:
Ketan Mehta, T.J. Jankun-Kelly, "Detection and Visualization of Defects in 3D Unstructured Models of Nematic Liquid Crystals," IEEE Transactions on Visualization and Computer Graphics, vol. 12, no. 5, pp. 1045-1052, Sept. 2006, doi:10.1109/TVCG.2006.133
