Method of measuring splice loss in optical fibers

摘要

A method of determining splice loss 10 log (1-PR/PO) that is practiced at the location of a splice between one ends of input and output fibers. A reference level PO of light that is transmitted out of the one end of the input fiber is obtained by inserting it into an integrating cylinder of split block construction, prior to making the splice, and coupling diffuse light in the cylinder to a radiometer. After the ends of the fibers are spliced together, the splice and a significant portion of the adjacent length of output fiber exhibiting substantial leaky mode radiation that is caused by the splice, is located in the cylinder. With light of the reference level in the input fiber being incident on the splice, the radiometer provides an indication PR of light lost as a result of the splice. The indication PR may also be obtained by integrating only light radiated from a length of the leaky mode section of output fiber, which has been found to extend to approximately one foot downstream of the splice.