Method for fusion splicing optical fibers and fusion splicer

Abstract

A method and apparatus capable of fusion splicing optical fibers to have a low loss or a prescribed loss. The method includes (a) detecting fiber positions and core positions of optical fibers to be spliced at an abutting position and a fiber offset that is caused when said optical fibers are in core alignment (b) determining the self-alignment ratio corresponding to the preferred melted condition value based on a predetermined expression for a relationship between melted condition value and self-alignment ratio, (c) determining an intentional offset that achieves a prescribed splicing loss based on the fiber offset and the self-alignment ratio, (d) aligning the core positions by offsetting the intentional offset value, and (e) heating and fusing the optical fibers.