PANDA polarization maintaining fiber with a mechanical reinforcing outer layer for tight bend applications

PANDA polarization maintaining (PM) fibers for tight bend applications are presented that can satisfy both optical and mechanical characteristics. Optical optimization of conventional-cladding structures and trench-cladding structures is discussed regarding effective cutoff wavelength under short-length and tight bend conditions. Both trench-cladding PM fiber and conventional PM fiber with 80 μm cladding diameter had similar effective cutoff wavelengths for lengths of 0.5 m. Bending loss at 2 mm radius was less than 0.1 dB/turn at 1550 nm. Additionally, improved mechanical reliability by incorporating a reinforcing outer glass layer is demonstrated on PM fiber for the first time.