| 摘要 |
PROBLEM TO BE SOLVED: To provide a single/multmode optical fiber coupler that has a prescribed branching ratio at wavelengths in both a single-and multi mode areas, and also to provide its manufacturing method. SOLUTION: In two single-mode fibers having the coating removed, their cladding diameters are preliminarily formed arrow at 40μm or less and then, this narrow diameter part is heated, drawn and welded, with a part of this welded part coupled optically by a high-intensity beam. As a result, since heat capacity is small in the part to be heated, the heating and the drawing are performed smoothly. enabling the single/multi mode optical fiber coupler to be easily obtained which has a prescribed branching ratio at both single-and multmode regions. |
