| 摘要 |
PROBLEM TO BE SOLVED: To provide a polarization-maintaining optical fiber without deteriorating the crosstalk characteristics of polarized waves after its fusion splicing, and to provide a method for manufacturing its preform. SOLUTION: The angle made by the straight line passing the center of the one stress imparting part 23 and the center of the core 21 and by the straight line passing the center of the other stress imparting part 23 and the center of the core 21 is specified to <=3 deg.. While the optical fiber preform is held, one of the insertion holes for the stress imparting members is opened in the clad preform. The optical fiber preform is rotated by 180 is the circumference direction as the preform held, and then the other insertion hole is opened in the clad preform. |
