The Vacuum Ultra Violet (VUV) regions are surrounded by “above” the ultraviolet (UV) spectral region (from 200 nm) and the long wavelength side of the Hard X-Ray region below (around 1 nm).
Three main regions make up the Vacuum Ultra Violet domain:
- The Far Ultra Violet (FUV): 200-120 nm corresponds to the natural barrier of the transmittance of radiation through any window material
- The Extreme Ultra Violet (EUV): 120-10 nm
- The Soft X-Rays (Soft X): 15-0.2 nm that requires the use of large deviation angles up to 170°