Fibertek reports on the design and performance of two high power ruggedized Thulium fiber laser systems designed for spaceborne and airborne applications. The spaceflight system is a 100 W average power, linearly polarized, 1940 nm thulium doped fiber laser (TDFL) packaged in a hermetic 11-liter module. The airborne system is an all-fiber, narrowlinewidth, master oscillator power amplifier architecture with staged thulium fiber amplifiers with 80 W peak power and 20 W average power in a quasi-continuous temporal waveform. The airborne laser includes programmable digital phase codes with bit rates up to several GHz. We will discuss the overall system performance and environmental qualification testing of both systems.
Fibertek has designed and is building a spaceflight (TRL 5-6) high-efficiency, high reliability (97.2% for 5-year mission) 100 W average, 1940 nm thulium doped fiber laser (TDFL) meeting all requirements for a NASA Earth Science spaceflight 2 μm Ho:YLF pump laser. These include polarization extinction ratio <16dB, diffraction limited beam quality, narrow linewidth (0.35nm) and >50% optical to optical efficiency. High reliability laser package, optimized for space environment and SWAP has size 10.6”x13.8”x4.4”and weight 30lbs. A summary of laser package design is presented, including structural and thermal analysis. Preliminary environmental testing results of the space laser are also presented. A spaceflight 100 W PM Tm laser provides a path to space for a pulsed, Q-switched 2 μm Ho:YLF laser with ~80 mJ/pulse at 100-200 Hz.