THE SPECTRAL AND LASING PROPERTIES OF SEVERAL NEW DYES IN ULTRAVIOLET REGION

Four new 7-alkoxy-4-methyl coumarin dyes have been investigated, reporting first mesurements of their absorption spectra, fluorescence spectra and lasing properties. In comparison with the fluorescence peak of coumarin dye 4MU, those of the new coumatins shifted about 60 nm to the short wavelength side. These four new dyes give laser emission in the UV region. The laser tunable range and energy conversion efficiency have been determined. Using time-resolved techniques we have observed their kinetic fluorescence and determined the relevant fluorescence life-time.