Bend performance of leakage channel fibers

Bend loss of the first three modes of leakage channel fibers with various designs are studied using finite element method. It is found that very low bend loss at small bend radius can be achieved with large d/Delta. It is also found that best differential mode loss is achieved at large bend radius. It is further found that 2nd order mode loss becomes 9.1 times of fundamental mode loss at small bend radius for the bend orientation where the bending plane crosses centers of two holes and independent of d/Delta. Bend loss dependence of bend orientations are also studied. Excellent agreement between experiment and simulation is obtained.