X-ray fluorescence analysis and apparatus therefor
AssigneeRigaku Industrial Corporation
InventorMotoyuki Yamagami
Life of this patent
Estimating the term…
Abstract
In order to render the value of the fluorescent X-ray strength Ia2 of a standard sample 2 multiplied by the ratio PF1/PF2 between respective grading coefficients of standard samples 1 and 2 to approach the value of the fluorescent X-ray strength Ia1 of the standard sample 1, specific glancing angles øa* and øb* are determined. The abundance of a substance of interest is determined from fluorescent X-ray strengths Ia3 and Ib3 of a sample to be measured that is irradiated at the determined specific glancing angles øa* and øb*, to thereby provide an accurate determination of the abundance of the substance of interest.
Claims14
A fluorescent X-ray analyzing method for measuring fluorescent X-rays emitted from a substance of interest present on a surface area of a sample by irradiating the surface area of the sample with primary X-rays, said method comprising:
- a first step of measuring a strength of fluorescent X-rays by projecting the primary X-rays onto standard samples 1 and 2 having different distribution of the substance of interest, but having the same abundance of the substance of interest, so as to impinge thereupon at a plurality of different glancing angles of ø1 to øn;
- a second step of determining a ratio between the strengths Ia1 and Ib1 of the fluorescent X-rays, emitted from the standard sample 1, for two glancing angles øa and øb (where øa<øb) arbitrarily chosen from the plural glancing angles, as a grading coefficient PF1 of the standard sample 1 and also determining a ratio between the strengths Ia2 and Ib2 of the fluorescent X-rays, emitted from the standard sample 2, for those two glancing angles øa andøb, as a grading coefficient PF2 of the standard sample 2, and then determining the corresponding specific glancing angles øa* and øb* at which the ratio of Ia2·PF1/PF2 can take a value approximating to Ia1, and
- a third step of determining the abundance of the substance of interest from strengths Ia3 and Ib3 of the fluorescent X-rays emitted from a sample to be measured when the latter is irradiated with the primary X-rays at respective specific glancing angles øa* and øb*.
An X-ray fluorescence spectrometer for measuring fluorescent X-rays emitted from a substance of interest present on a surface area of a sample by irradiating the surface area of the sample with primary X-rays, said spectrometer comprising:
- a measuring unit for measuring a strength of fluorescent X-rays by projecting the primary X-rays onto standard samples 1 and 2 having different distribution of the substance of interest, but having the same abundance of the substance of interest, so as to impinge thereupon at a plurality of different glancing angles of ø1 to øn;
- a calculating means for determining a ratio between the strengths Ia1 and Ib1 of the fluorescent X-rays, emitted from the standard sample 1, for two glancing angles øa and øb (where øa<øb) arbitrarily chosen from the plural glancing angles, as a grading coefficient PF1 of the standard sample 1 and also determining a ratio between the strengths Ia2 and Ib2 of the fluorescent X-rays, emitted from the standard sample 2, for those two glancing angles øa and øb, as a grading coefficient PF2 of the standard sample 2, and then determining the corresponding specific glancing angles øa* and øb* at which the ratio of Ia2·PF1/PF2 can take a value approximating to Ia1, and
- an abundance determining unit for determining the abundance of the substance of interest from strengths Ia3 and Ib3 of the fluorescent X-rays emitted from a sample to be measured when the latter is irradiated with the primary X-rays at respective specific glancing angles øa* and øb*.
Dependencies are inferred from the claim text.