Patent ID: 7187751

Claim:
An X-ray fluorescence spectrometer comprising: an X-ray source for irradiating primary X-rays towards a sample, a detecting device for measuring the intensity of secondary X-rays emanating from the sample, and a calculating device for calculating a concentration of an element contained in the sample and operable to calculate a theoretical intensity of the secondary X-rays, emanating from various elements contained in the sample, on the basis of an assumed concentration of the element and perform an optimizing calculation to determine the assumed concentration of the element so that the theoretical intensity and an intensity measured by the detecting device can match with each other, wherein as far as unmeasured elements, of which fluorescent X-rays are not measured, are concerned, the calculating device is operable to assume concentrations of the plural unmeasured elements and, also, to utilize, in place of the secondary X-rays emanating from the unmeasured elements contained in the sample, scattered X-rays of the primary X-rays at least equal in number to the number of the unmeasured elements, of which concentrations are assumed, and including scattered X-rays of different wavelengths before they are scattered from the sample.