Determining optical fiber splice loss

摘要

In the formation of a splice between two optical fibers 10 and 12, the splice loss is determined by locally supplying an optical signal to each fiber, in a direction towards the end to be spliced e.g. through a coupling 18, and measuring the signal levels P1 and P2 at the end of the fibers before making the splice, and using a symmetric detector 22 to measure in one of the fibers the signal levels D1 passing in one direction towards the splice and D2 in the opposite direction after passing through the splice, the splice loss being calculated from (P2-D2)-(P1-D1). Two forms of symmetric detector are described in which equal responses to optical signals in either direction in a fiber are obtained by bending the fibre and arranging a detector symmetrically with respect to the curve of the fibre.