Patent ID: 8340248

Claim:
An X-ray diffraction method comprising: a) providing an X-ray diffraction apparatus including: a device for generating an X-ray parallel beam, which will be incident on a sample; a mirror for reflecting diffracted X-rays from the sample, the mirror utilizing diffraction phenomena and the mirror having a reflective surface consisting of a combination of plural flat reflective surfaces, which are located so that an angle defined in a plane parallel to a diffraction plane becomes constant among all the flat reflective surfaces, the angle being between each flat reflective surface and a line segment connecting a center of the each flat reflective surface and the sample, and further so that a crystal lattice plane that causes reflection is parallel to each flat reflective surface; and an X-ray detector for detecting reflected X-rays from the mirror, the X-ray detector being one-dimensional position-sensitive in a plane parallel to the diffraction plane, wherein a relative positional relationship between the flat reflective surfaces and the X-ray detector is determined, in a plane parallel to the diffraction plane, so that reflected X-rays that have been reflected at different flat reflective surfaces reach different points on the X-ray detector respectively; b) allowing the X-ray parallel beam to be incident on the sample; c) detecting diffracted X-rays, which have been reflected at the mirror and have different diffraction angles, distinctly and simultaneously; and d) performing a corrective operation for separately recognizing different reflected X-rays that have been reflected at the different flat reflective surfaces and that are subject to being mixed with each other on a same detecting region of the X-ray detector; wherein the corrective operation is carried out based on an intensity distribution curve of the diffracted X-rays along a beam width of the diffracted X-rays, the intensity distribution curve being made in consideration of a phenomena in which X-rays are diffracted at locations also below a surface of the sample.