| 摘要 |
PROBLEM TO BE SOLVED: To increase the taper angle of the tip of a core and to increase the light transmission efficiency by etching the tip of an optical fiber using the meniscus of an etching liquid and then dipping it into the etching liquid for etching. SOLUTION: First, an optical fiber 1 is lowered, its end face is matched with an interface 6 between an etching liquid 4 and an organic solvent 5, and a meniscus is formed at the tip. While the meniscus is maintained by pulling for small distance, the tip is etched. Then, the optical fiber is lowered, and the tip is dipped into the etching liquid 4 for etching. Finally, the optical fiber 1 is taken out of the etching liquid 4, is washed by water and alcohol successively, and then a metal covering layer is formed, and a small opening is formed at the tip, thus setting the taper angle of the first conical part of the tip to a second-stage taper shape that is larger than the taper angle of a second conical part adjacent to the side of a base edge without changing the concentration of GeO2 to be added to a core 2. |
