A Comparative Study of X ray Diffraction Pattern Obtaining Methods for Portable Diffractometer

With the development of portable X-ray diffractometer for in-situ analysis, powder diffraction patterns are obtained in a diffractometer with a two-dimensional area detector.However, detector system and experimental geometry introduces distortion into acquired data.To obtain accurate diffraction pattern information, it is necessary to apply calibrations.Position of the X-ray incident beam centre on the detector and any non-orthogonality of the detector to the direct beam are the primary considerations.Although many calibration methods have been developed to calculate the intensity-scattering-angle dependence, there are few comparation between them.The purpose of this paper is to investigate these methods.The methods considered include the histogram method, the coordinate transformation method and the Nelder-Mead Simplex method.From the achievement of qualitative analysis angle, we experimentally compare the performance of the methods and illustrate properties such as accuracy and computational efficiency.