Insertion loss measurement of low loss fiber optic splices

Results from a National Electronics Manufacturing Initiative (NEMI) project, formed to improve aspects of fiber optic fusion splicing, are reported. The focus of this paper is ultra low loss splicing for telecommunications product assembly, with typical loss of G0.05 dB per splice for standard SMF-SMF. A detailed review of available industry standards, relevant to splice loss acceptance criteria and loss test procedures, revealed the standards are generally inadequate for low loss splicing. Various project participants using different equipment and procedures performed fiber preparation, splicing, splicer loss estimation, and actual loss measurements. An industry standard gage repeatability and reproducibility (GR&R) analysis was used to compare the data. Loss measurement set-ups based on a cutback method for dissimilar fiber (SMF-EDF) splices showed significant directionality in some cases, and root cause was identified using a round robin approach. Several of the methods evaluated will form the basis for a new loss measurement standard for low-loss and dissimilar fiber splices.