Patent Number: 
Section: claims

1. An X-ray optical system for small angle scattering, comprising:a multilayer mirror having a parabolic reflecting surface for collimating an X-ray beam,a narrow slit for restricting a width of the X-ray beam, anda scattering slit in described order from an X-ray source sides, said scattering slit having an aperture center whose position is variable and an aperture width which is variable. 2. An X-ray optical system for small angle scattering, comprising:a narrow slit for restricting a width of an X-ray beam,a multilayer mirror having a parabolic reflecting surface for collimating the X-ray beam, anda scattering slit in described order from an X-ray source side, said scattering slit having an aperture center whose position is variable and an aperture width which is variable. 3. An X-ray optical system for small angle scattering, in which:(a) a multilayer mirror having a parabolic reflecting surface for collimating an X-ray beam, an optical-path selecting slit device, a small-angle selecting slit device and a specimen-side slit are arranged in the described order from an X-ray source side;(b) the optical-path selecting slit device has an aperture through which the X-ray beam can pass, so that selective switching can be performed between a first state in which a parallel beam having been reflected at the multilayer mirror passes through the aperture and a second state in which an X-ray beam having bypassed the multilayer mirror passes through the aperture;(c) the small-angle selecting slit device has a narrow slit for small angle scattering measurement and a broad aperture, so that switching can be performed between a first state in which a beam width of the parallel beam having been reflected at the multilayer mirror is restricted, by the narrow slit and a second state in which the parallel beam having been reflected at the multilayer mirror passes through the broad aperture; and(d) an aperture center position and an aperture width of the specimen-side slit are variable. 4. An X-ray optical system for small angle scattering, in which:(a) a multilayer mirror having a parabolic reflecting surface for collimating an X-ray beam, an optical-path selecting slit device, a small-angle selecting slit device and a specimen-side slit are arranged in the described order from an X-ray source side;(b) the optical-path selecting slit device has an aperture through which the X-ray beam can pass, so that selective switching can be performed between a first state in which a parallel beam having been reflected at the multilayer mirror passes through the aperture and a second state in which an X-ray beam having bypassed the multilayer mirror passes through the aperture;(c) the small-angle selecting slit device can be selectively equipped with a first component having a narrow slit for small angle scattering measurement and a second component having a broad aperture; and(d) the specimen-side slit has an aperture for small angle scattering measurement, and its aperture center position and its aperture width are variable.