Angular emission and self-absorption studies of a tin laser produced plasma extreme ultraviolet source between 10 and 18nm

Extreme ultraviolet spectra from a tin laser produced plasma have been recorded over a range of angles between 20° and 90° from the target normal. Absolute intensity measurements are presented of both the 2% band centered on 13.5nm and the total radiation emitted by the plasma between 10 and 18nm. The in-band intensity is seen to be relatively constant out to an angle of 60° from the target normal, beyond which it drops off quite steeply. The spectra at wavelengths greater than 13.5nm are strongly influenced by self-absorption by ions ranging from 6+ to 10+.