High Energy Laser Component Technology for Eye-Safer Fiber Lasers

Traditional diode end pumped single mode fiber laser designs are limited in terms laser power pumping and energy extraction. Double clad large mode area fibers are easier to scale up and typically utilize fiber delivered diode pumping at various laser gain length intervals in order to overcome fiber aperture power density limitations. Even with such improvements, current high power fiber lasers still exhibit numerous trade-offs in laser beam quality, system size and diode pump fiber delivery complexity and cost. New high power fiber laser designs should circumvent these complex and expensive system integration issues with simpler, smaller and more straightforward scalable designs. New high power fiber laser architectures should eliminate pump beam combining, free space pump beam launch optics and multiple fiber coupling. Kigre proposes to integrate unique athermal fiber gain materials and pumping architectures into compact high power eye-safe fiber laser devices operating in the 1.5 micron region. This innovative approach employees standard 1cm linear diode arrays configured for direct side pumping of rectangular clad large mode area erbium fluorophosphate fibers without the need for free space optics, pump beam conditioning optics or pump delivery fibers.