摘要 |
Laser light in the wavelength range of 400 - 480 Nm is obtained with a dyestuff laser containing a dyestuff of the general formula <IMAGE> I wherein E denotes one of the radicals <IMAGE> <IMAGE> <IMAGE> +TR <IMAGE> R1-R4 independently of one another denote hydrogen, alkyl, trifluoromethyl, alkoxy, aralkoxy, halogen, alkenyloxy, the carboxyl, cyano, alkylsulphone, arylsulphone, carboxamide or sulphonamide group or the carboxylic acid ester group, or R1 and R2, or R3 and R4, conjointly represent a fused benzene ring and m and n independently of one another denote 0, 1 or 2, with the proviso that the radical E contains at least one sulphonic acid group if m and n represent 0, and wherein the radical E can be further substituted, in a solvent which does not interfere with the emission, at a concentration, which emits laser beams, of, preferably, 10-2 to 10-5 mols/liter. |