Rigorous and approximate analysis of metallic gratings in soft X-ray and EUV regions

Diffractive components in X-ray and UV regions have several attractive applications, but analysis in those regions has not been thoroughly investigated. Besides, in the X-ray and UV regions the complex refractive indices of metals differ substantially from the values in the visible region of the spectrum. The consequences of this phenomenon are analyzed for metallic structures illuminated by wavelengths ranging from infrared to soft X-rays. The rigorous diffraction theory and the thin element approximation is applied to study the behavior of both wire-grid polarizers and inductive grid filters. Single layer film theory is used to enhance the reliability of the thin element approximation.