nLIGHT Introduces New Line of Photodarkening Resistant Fibers

Vancouver, WA USA  March 16, 2009 

nLIGHT Corporation (nLIGHT) announced today the availability of new highly doped, photodarkening resistant ytterbium fibers with up to 60 percent (%) higher absorption at 920 nanometer (nm) and pump conversion efficiencies routinely over 75 %.

In 2005 the fiber division of nLIGHT, previously LIEKKI Corporation, was the first active fiber manufacturer to publish techniques for efficiently measuring and mitigating photodarkening with its proprietary direct nanoparticle deposition (DND) fiber production technology. This effort has continued unabated and resulted in new fiber designs and processes to further reduce the detrimental effects of photodarkening.

The large mode area (LMA), low numerical aperture (NA) fibers offered by nLIGHT today exhibit a fivefold decrease in loss under accelerated stress testing conditions. The loss of LMA, high NA fibers is even below the measurement capability of the accelerated test. In addition these new ytterbium fibers offer up to 60 % higher absorption at 920 nm and show pump conversion efficiencies routinely over 75 %.

Figure 1: LIEKKI™ Yb2000 fiber with low photodarkening

The new photodarkening resistant LIEKKI™ ytterbium fibers are available in core/clad geometries ranging from 7/125 µm to 30/250 µm in non-polarization and polarization maintaining versions.