Soft and Ultrasoft X-Ray Fluorescent Spectrometer Using Total Reflection Monochromator

Abstract

Since specular reflection of characteristic X-rays can become nearly total external reflection at grazing incidence, total reflection analysis offers an alternative to the wavelength dispersive method based on Bragg reflection. Using curves of calculated and measured intensity versus glancing angle, a high-efficiency mirror material was selected and the optimized optical geometry and filtering conditions were determined. Short wavelength X-rays could be eliminated and overlapping interference of equal and longer wavelength X-rays was excluded using the equation for determining the element concentration. Analytical examples for Al, C and B are described.