Patent ID: 8111807

Claim:
A crystallite size analysis method using powder x-ray diffraction for sampling intensity data of a diffraction beam generated from a powder sample when the sample is irradiated with an x-ray beam, and determining, based on the diffraction beam intensity data, the size of crystallites included in the sample, said method comprising the steps of: supporting the sample on a flat rotary specimen stage; restricting, by using a divergence slit, the width of an x-ray beam emitted by an x-ray source, and irradiating the sample at an incidence angle θ; allowing the diffraction beam generated from the sample to pass through a scattering slit and a light-receiving slit while restricting the beam width by the slits; receiving the diffraction beam that has passed through the light-receiving slit by an x-ray detector placed at the position of a diffraction angle 2 θ, and generating diffraction beam intensity data(Ij) (j=0,1, . . . ,n−1) by the x-ray detector; fixing the x-ray incidence angle θ and diffraction angle 2 θ at corresponding intrinsic values on the sample; rotating the sample within a plane at a designated step angle by the flat rotary specimen stage; measuring the diffraction beam intensity (Ij) by the x-ray detector at the position of each step along the rotation within a plane and storing each measured diffraction beam intensity (Ij) in a memory; calculating, by a controller, a variance ((ΔI particle ) 2 ) due to particle statistics from the measured plurality of diffraction beam intensities (Ij) and storing the variance ((ΔI particle ) 2 ) in the memory; and calculating, by a controller, based on the variance((ΔI particle ) 2 ) due to the particle statistics, the size of the crystallites included in the sample.