In order to increase the laser energy through energy conversion of the pumping light, the converter dye BBQ was mixed in the laser dye LD490 solutions. The laser was pumped by an Ar flashlamp with a relatively long pulse width. Various concentrations of dye mixture LD490+BBQ in methanol were used. The experimental results show that the laser output energy increases by 180% with a dye mixture made of 4.5×10−6mol/l  BBQ over the maximum output obtainable with the laser dye alone, while the laser power increases by 92% with the same conditions. Comparison with previous work [K. S. Hanetal., J. Appl. Phys.60, 3414 (1986)] is discussed.