| 摘要 |
PURPOSE:To maintain a low loss over a visible light-near IR region by constituting a core of a polymer having a specific dispersibility (for example, deuterated polymethyl methacrylate). CONSTITUTION:A core is formed of a polymer, for example, a material prepd. by bulk polymn. of a deuterated methyl methacrylate monomer and adjusting the dispersibility expressed by the ratio between a weight average mol.wt. and a number average mol.wt. to <=2.0. A uniform and transparent polymer blend consisting of, for example, a vinylidene fluoride-tetrafluoroethylene copolymer and polymethyl methacrylate and is lower in the refractive index than the core is used as a sleeve component with respect to such core and an optical fiber having the core-sleeve constitution is formed by a combined spinning method or the like. Since the polymer having <=2 dispersibility and an excellent mol.wt. distribution is used in the above-mentioned way, the fiber having the uniformity in the core diameter and out of roundness, good adhesion to the sleeve and a low loss of light is thus obtd. |
