| 摘要 |
PURPOSE:To obtain a side tunnel shape constant polarization fiber excellent in the polarization characteristics or the like in the good reproducibility by boring the circular holes in the axial symmetry in both sides of core of a glass rod and enlarging the diameters by the etching to form the hollow parts. CONSTITUTION:The circular holes 14a, 14b are bored in the axial symmetry in both sides of a core 12 apart from the core 12 in a glass rod 11 having a rod-shaped glass layer 12 for the core. Then the sides of the glass rod 11 are ground and two faces 15a, 15b which are mutally parallel and symmetrical in relating to a line L passing both a center of core 12 and the centers of circular holes 14a, 14b are formed. Successively after the diameters of circular holes 14a, 14b are enlarged by the etching until touching the core 12, the aimed side tunnel shape constant polarization fiber available as the coherent light transmission is obtained by spinning the rod 11 and forming a flattened shape core 17 and the hollow parts 19a, 19b of the axial symmetry touching the core 17. |
