Luminescent coolants for solid-state lasers

Solutions of 13 fluorescent dyes have been used as energy transfer agents in place of the normal coolant of a Nd-YAG laser. Dye mixtures were used in a few cases where incomplete absorption of flashlamp pump energy was observed. Improvements of over 100% in laser output were observed for some dyes having a long Stokes shift when tested at both a low-input energy and a low-pulse rate. However, the absolute improvement in laser output for these dye solutions was small, and the improvement could be obtained almost as well by merely increasing the pulse rate. Various factors associated with the effectiveness of transfer-dye solutions are discussed.