Relative spectral power measurement of laser-pulse for high power laser facility

The relative spectral power is used for evaluating the spectral distribution of ultrashort laser pulse. The relative spectral power measurement for ultrashort laser pulse is studied based on the standard illuminant of bromine-tungsten lamp, and analytical expressions of the relative spectral power are clearly given. Experimental results for the relative spectral power measurement on SILEX-I laser facility using SP2760 spectrometer show that the spectral distribution evaluated by the relative spectral power is significantly different comparing with the original spectral response. The uncertainty-analysis of experimental results is also given, and the extended relative uncertainty is 1.7%.