Loss factors analysis for single-mode fiber splicing without core axis alignment

Optimum splice condition is clarified in single-mode fiber splicing without core axis alignment by analyzing loss factors quantitatively. Dominant splice loss factors are core deformation caused by fiber axis discrepancy and core axis misalignment caused by core eccentricity. To suppress average splice loss to less than 0.1 dB, average core eccentricity suppression to less than 0.35 mu m is necessary. A new method for setting fiber endface gaps accurately and quickly is proposed.