Highly efficient tunable pulsed dye laser longitudinally pumped by green diodes

We report a highly efficient, compact low-cost tunable dye laser pumped directly by green laser diodes. A tunable dye laser quasi-longitudinally pumped by two multimode InGaN diodes (520nm), was implemented in a 200ns pulsed mode with a 2Hz repetition frequency. The lasing threshold energies were found to be 0.23-0.37 using an output mirror with 13% transmission. The best efficiency at the lasing maximum for Pyrromethene 567 exceeded 25% when the slope efficiency in broadband cavity configuration was 43% at an absorbed pump energy of . The laser overlapped a wide spectral region of 145nm (from 537 to 682nm) with a linewidth of 1nm. This indicates that green diodes can be used as an effective pump source for tunable dye lasers. Such lasers will be useful for spectroscopy, medicine and other fields due to their compactness and low cost.