Line ratio values for spectral calibration in the vacuum ultraviolet by using laser produced plasmas

Relative efficiency of a 3 m normal incidence vacuum ultraviolet monochromator has been determined for the 38.6-133.7 nm spectral range, by using the line ratio method. Emission line intensities of line pairs with a common upper level of ionized oxygen, nitrogen, carbon, sulfur and aluminum, have been measured. A laser produced plasma of different materials (ceramics, polyethylene, zinc sulfide and aluminum) has been used as light source. Values of line ratios used for calibration of the relative spectral efficiency have been discussed. Also, the efficiency has been obtained by using the continuum spectrum of a laser-produced tungsten plasma. The results of both methods are in good agreement. (C) 1997 Elsevier Science Ltd.