Abstract: An X-ray optical system for small angle scattering has a parabolic multilayer mirror and, so that switching to other X-ray incident optical systems for X-ray analysis can be easily performed. A parabolic multilayer mirror, an optical-path selecting slit device, a small-angle selecting slit device and a Soller slit are arranged between an X-ray source and a specimen-side slit. An X-ray beam having passed through the first aperture of an aperture slit plate is interrupted by the optical-path selecting slit. An X-ray beam having passed through the second aperture of the aperture slit plate is reflected at the reflecting surface of the multilayer mirror to become a parallel beam. This parallel beam passes through an aperture of the optical-path selecting slit device. The beam width is restricted by a narrow slit of the small-angle selecting slit device.

Abstract: Parallel X-ray beams with two kinds of wavelength are made with the use of a single parabolic multilayer mirror. A single parabola prepared for a CuKa X-ray is used for making parallel X-ray beams of both the CuKa X-ray and the CoKa X-ray. The CuKa ray emitted from a first X-ray focal spot located at the focus of the parabola is reflected at a reflecting surface composed of the parabola to become a parallel beam going out. When a second X-ray focal spot is arranged at the position apart from the first X-ray focal spot by a predetermined distance, the CoKa X-ray emitted from the second X-ray focal spot is reflected at the same reflecting surface to become a parallel beam going out.

Abstract: In the measurement with the focusing method, an X-ray beam from an X-ray source passes through an opening of a path-selection slit device and is narrowed by a divergence slit with a predetermined divergence angle and is thereafter incident upon a sample. The changing operation from the focusing method into the parallel beam method is carried out by turning, by 180 degrees, the path-selection slit device around its axis of rotation and by moving the divergence slit in a direction perpendicular to an X-ray traveling direction. Then, the X-ray beam from the X-ray source is reflected by a multilayer mirror to become a parallel beam and passes through the opening of the path-selection slit device and is thereafter incident upon the sample. Thus, the turning of the path-selection slit device enables the change between the focusing method and the parallel beam method, requiring no re-setting operation for the optical system.

Abstract: Parallel X-ray beams with two kinds of wavelength are taken with the use of a single parabolic multilayer mirror. A single parabola prepared for a CuK&agr; X-ray is used for taking parallel X-ray beams of both the CuK&agr; X-ray and the CoK&agr; X-ray. The CuK&agr; ray emitted from a first X-ray focal spot located at the focus of the parabola is reflected at a reflecting surface composed of the parabola to become a parallel beam going out. When a second X-ray focal spot is arranged at the position apart from the first X-ray focal spot by a predetermined distance, the CoK&agr; X-ray emitted from the second X-ray focal spot is reflected at the same reflecting surface to become a parallel beam going out.

Abstract: An X-ray optical system for small angle scattering has a parabolic multilayer mirror and, so that switching to other X-ray incident optical systems for X-ray analysis can be easily performed. A parabolic multilayer mirror, an optical-path selecting slit device, a small-angle selecting slit device and a Soller slit are arranged between an X-ray source and a specimen-side slit. An X-ray beam having passed through the first aperture of an aperture slit plate is interrupted by the optical-path selecting slit. An X-ray beam having passed through the second aperture of the aperture slit plate is reflected at the reflecting surface of the multilayer mirror to become a parallel beam. This parallel beam passes through an aperture of the optical-path selecting slit device. The beam width is restricted by a narrow slit of the small-angle selecting slit device.

Abstract: X-ray diffraction apparatus is provided in which the focusing method and the parallel beam method can be changed easily for each other. In the measurement with the focusing method, an X-ray beam from an X-ray source passes through an opening of a path-selection slit device and is narrowed by a divergence slit with a predetermined divergence angle and is thereafter incident upon a sample. The changing operation from the focusing method into the parallel beam method is carried out by turning, by 180 degrees, the path-selection slit device around its axis of rotation and by moving the divergence slit in a direction perpendicular to an X-ray traveling direction. Then, the X-ray beam from the X-ray source is reflected by a multilayer mirror to become a parallel beam and passes through the opening of the path-selection slit device and is thereafter incident upon the sample.