| 摘要 |
PURPOSE:To obtain a long-sized base material for an optical fiber retaining its plane of polarization and causing a small loss, by forming a glass layer for a clad on the inner wall of a glass pipe, heating and evacuating the pipe to provide a hollow elliptical shape, putting a core rod in the pipe, and melt-bonding them together by heating. CONSTITUTION:A glass layer 2 for a clad is deposited on the inner wall of a quartz glass pipe 1. The pipe 1 is attached to a glass lathe 4 in a fixed state, and the pipe 1 is heated while moving an oxyhydrogen burner 3 along one side of the pipe 1. At the same time, the pipe 1 is evacuated. The pipe 1 is turned by 180 deg., and it is heated and evacuated by similar operation to provide an elliptical external shape. A core rod 5 is put in the pipe 1, and they are melt- bonded together by heating with the burner 3 in an evacuated state to obtain a base material for an optical fiber retaining its plane of polarization. |
