350 W High-Brightness Multi-Emitter Semiconductor Laser Module Emitting At 976 Nm

This paper reports a multi-emitter laser module realization, based on internally developed InGaAs/GaAs 190 mu m ridge High Power Diode Lasers (HPDL), emitting at 976 nm. Single diode lasers shown a highly efficient power conversion and good emitted beam characteristics together with excellent long term reliability. The multi-emitter laser module, using 20 diodes polarization and spatially multiplexed, demonstrated up to 350 W of output power at 976 nm; the absence of fiber coupling degradation at high bias currents, thanks to the limited beam blooming from the laser diodes, ensure a good linearity in the operating conditions. The package has a compact footprint of 54 mm x 140 mm, with an output fiber of 200 um core / 220 um cladding, and 95 % of the emitted power is within 0.16 numerical aperture (N.A.). Present realization of high-power multi-emitter semiconductor laser source is suitable for production of high power single modules fiber laser, moreover contributing to an important reduction of the overall fiber laser cost by effectively reducing the number of the pump modules.