Patent Number: 
Section: abstract

A multilayer mirror 1 that has elliptical reflection faces and provides a divergent angle xcex4 of X-rays, is included. The elliptical reflection faces of the multilayer mirror 1 have two focal points. When an X-ray source 2 is arranged at one focal point A, and X-rays that are diverged from the X-ray source 2 are reflected at the multilayer mirror 1, the reflected X-rays converge on another focal point B. The X-ray source 2 is arranged at one focal point A of the multilayer mirror 1. Additionally, a distance L2 from the center of the reflection faces of the multilayer mirror 1 to another focal point B (in other words, convergent point of reflected X-rays) is set to make a convergent angle xcex8c of X-rays at the focal point B nearly twice as great as the divergent angle xcex4. With the above-noted configuration, both small angle resolution and intensity of incident X-rays to a sample may be optimized, and small angle scattering may be performed with high precision.