LIEKKI™ Yb1200-20/400 fibers are highly doped ytterbium fibers for medium-power fiber lasers and amplifiers. They combine a large core with excellent beam quality and 400 μm cladding capable of accepting medium-pump powers.

LIEKKI™ Yb1200-20/400 fibers are available as double cladding (Yb1200-20/400DC) and double cladding polarization maintaining (Yb1200-20/400DC-PM) fibers.