Optical fiber end preparation using a CO_2 laser

A new method for obtaining good fiber ends with the help of a CO(2) laser is described. In principle, the fiber is exposed to a focused CO(2) laser beam and then fractured by applying tensile stress. Average coupling losses of a step-index and a graded-index multimode fiber, whose endfaces were prepared by this method, were both 0.35 dB without index-matching fluid. Average splice losses of these fibers were 0.05-0.06 dB, when their ends were fused with a CO(2) laser.