Measuring devices for X-ray fluorescence analysis

An apparatus including carrier plates for fluorescence analysis of specimens comprising in combination:

• a substantially gas-tight housing, supporting and positioning means in said housing for specimen carrier plates having plane surfaces, including abutment means defining a plane for engaging the plane surface of a specimen carrier plate with the plane surface of said plate coincident with the plane defined by said abutment means, said abutment means being mounted for pivotal movement about a pivotal axis lying in said plane defined by said abutment means, a detector for detection of radiation mounted on and projecting through a wall of said housing and having a detector axis perpendicular to said pivotal axis of said abutment means and passing through said plane defined by said abutment means, means for directing X-ray radiation along a radiation axis perpendicular to said pivotal axis and said detector axis to form a measuring region in which radiation is directed to said plane defined by said abutment means and including a radiation entry window in a wall of said housing for passage of said radiation from outside of said housing, said supporting and positioning means including a movable holder for a plurality of specimen carrier plates, said holder being movable to move each specimen carrier plate to said measuring region, pressure means to move said specimen carrier plate to engage its plane surface with said abutment means so that said plane surface and plane defined by said abutment means coincide and means to adjust said abutment means about said pivotal axis to vary the angle of said plane defined by said abutment means and the plane surface of said specimen carrier plate, so that said plane surface on each specimen carrier plate may be angularly adjusted precisely relative to said radiation axis.

An apparatus including carrier plates for fluorescence analysis of specimens comprising in combination:

• a substantially gas-tight evacuatable housing, U-formed supporting and positioning means in said housing as a pivot frame including an upper short arm with an underside connected by way of a vertical yoke member to a lower longer arm for specimen carrier plates having plane surfaces, including abutment means defining a measuring plane and located at the underside of said upper arm for engaging the plane surface of a specimen carrier plate with the plane surface of said plate coincident with the plane defined by said abutment means, said U-formed supporting and positioning means as the pivot frame including said abutment means being mounted for pivotal movement about a pivotal axis thereof lying in said plane defined by said abutment means, a detector for detection of radiation mounted on and projecting through a wall of said housing and having a detector axis perpendicular to said pivotal axis of said supporting and positioning means and passing through said plane defined by said abutment means, means for directing X-ray radiation along a radiation axis perpendicular to said pivotal axis and said detector axis to form a measuring region in which radiation is directed to said plane defined by said abutment means and including a radiation entry window in a wall of said housing for passage of said radiation from outside of said housing, said supporting and positioning means including a movable holder for a plurality of specimen carrier plates to said measuring region, pressure means carried by said lower longer arm of the pivot frame to move said specimen carrier plate to engage its plane surface with said abutment means to that said plane surface and plane defined by said abutment means coincide, and adjustment screw means operable from outside said housing to adjust said supporting and positioning means with said abutment means about said pivotal axis to vary the angle of said plane defined by said abutment means and the plane surface of said carrier plate relative to said radiation axis, so that said plane surface on each specimen carrier plate may be angularly adjusted precisely relative to said radiation axis, and means operable from outside said housing to move said holder to position each plate in said measuring region, and means to actuate said means to engage each specimen carrier plate with said abutment means.

The method of fluorescence analysis of a plurality of specimens on totally reflecting plane surfaces of specimen carrier plates with X-ray radiation irradiating and striking each specimen at a glancing angle to said plane surface to produce total reflection from the surface, and detecting radiation from the specimen by a detector having a detector axis passing through the specimen, said method in combination comprising directing X-ray radiation on a radiation axis intersecting the axis of said detector to form a measuring region at said intersection, moving said specimen carrier plates having totally reflecting plane surfaces in a plane perpendicular to said detector axis successively into a position traversed by said detector axis, adjusting abutment means defining a plane in said measuring region and pivotal about an axis in said plane and perpendicular to said detector axis and said radiation axis, said abutment means being angularly adjustable relative to said radiation axis, moving each carrier plate traversed by said detector axis into contact with said abutment means with its plane surface coincident with the plane defined by said abutment means, so that each specimen carrier plate may be positioned with its totally reflecting plane surface in the plane defined by said abutment means at a small angle to said radiation axis with the specimen irradiated on said plane surface under direct X-ray radiation and radiation reflected by said totally reflecting surface.