Offset and Tilt Loss in Optical Fiber Splices

Abstract

Transverse offset and angular misalignment (tilt) are serious causes of loss in multimode fiber splices. Our computation of these losses in multimode graded-index fibers reveals that the loss depends strongly on the power distribution in the fiber. We find that offsets of 0.1 of the core radius (or tilts of 0.1 of the fiber numerical aperture) cause a loss of 0.1 dB in the case of steady-state conditions, and between 0.34 and 0.38 dB if the power distribution is assumed as uniform. We compare these results with measured offset loss values and conclude that the steady-state distribution better reflects transmission line conditions than the uniform distribution.