This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
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Computer-assisted imaging and analysis has been proven to play an important role on highly accurate quantification of distribution of grain orientations. For instance, the orientation of individual grains can be determined by detecting the position of Kikuchi bands in electron backscattering patterns. Thousands of patterns can be captured and evaluated so that the grain orientations can be mapped [1]. The analysis of grain orientation patterns [2] can be performed by Hough transform [3], which was first introduced by Paul Hough in a patent filed in 1962 [3]. This technique was initially generated for automated shape analysis and track of particles through the viewing field of a bubble chamber.
Traditional EBSD methods use Hough transforms to determine the position of Kikuchi bands on the phosphor screen. [4 - 5] The Hough transform provides a proper technique for obtaining the parameters of a straight line and thus the positions of Kikuchi bands in an EBSP (electron backscatter diffraction pattern). Lines in the pattern are converted to spots in Hough Space.
[1] Schwarzer, R. A. (1997) Automated crystal lattice orientation
mapping using a computer-controlled SEM. Micron, 28 (3),
249–265.
[2] Krieger Lassen, N. C. (1994) Automated determination of crystal orientations from electron backscattering patterns. PhD Thesis,
Danmarks Tekniske Universitet, Lyngby, Denmark.
[3] Hough, P. V. C. (1962) A method and means for recognizing complex
patterns. US Patent 3 069 654.
[4] Krieger Lassen, N.C., Conradsen, K. & Juul Jensen, D. (1992). Image-processing procedures for analysis of electron back scattering patterns. Scanning Microsc 6(1), 115–121.
[5] Adams, B.L.,Wright, S.I. & Kunze, K. (1993). Orientation imaging: The emergence of a new microscopy. Metall Trans A 24A(4), 819–831.
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