Patent ID: 7440541

Claim:
A dual source XRF system comprising: a first x-ray source for directing x-rays in a first energy band at a sample, the first x-ray source chosen to not excite at least one high concentration element in the sample; at least a second x-ray source for directing x-rays in a second energy band at the sample, the second x-ray source chosen to excite the high concentration element; a monochromator in the optical path between the first and/or second x-ray source and the sample; a detector responsive to x-rays emitted by the sample after irradiation by the first and second x-ray sources; and an analyzer, responsive to the detector and configured: to detect at least a low concentration element in the sample based on irradiation of the sample by the first x-ray source and to detect at least the high concentration element in the sample based on irradiation of the sample by the second x-ray source, and to determine the amount of the high concentration element and the low concentration element and to adjust the determination of the low concentration element in the sample based on the determined amount of the high concentration element in the sample.