Power scaling of blue-diode-pumped Pr:YLF lasers at 523.0, 604.1, 606.9, 639.4, 697.8 and 720.9 nm

• A high-power blue diode laser was used as pump source with maximum output power of 7 W.
• Watt-level diode-pumped Pr:YLF lasers at 523, 607, 640, 698 and 721 nm can be realized.
• Laser beam qualities were measured with beam propagation factors of less than 1.8 for all these lasers.

We report a power scaled laser operation of diode-pumped Pr3+-doped LiYF4 crystal in single-end pumping geometry. Using a multi-mode InGaN diode laser, laser emissions at about 523.0, 604.1, 606.9, 639.4, 697.8 and 720.9 nm are achieved with maximum output power of 1.7, 0.6, 1.1, 2.3, 1.3 and 1 W, respectively. The corresponding slope efficiencies are found to be about 49%, 33%, 40%, 57%, 36% and 42%. Good laser beam qualities of these visible lasers are also found with measured beam propagation factors M2<1.8 for all of them.