| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-speed plastic optical fiber which is suitable for high-speed communication and can be made wider in band without the light loss by bending and the degradation in mechanical strength by constituting the high speed plastic optical fiber by supplying a specific core resin and a sheath resin in a molten state to a composite spinning dye, manufacturing an optical fiber precursor having >=1 cores and stagnating the precursor in an atmosphere above specific temperature, thereby constituting the optical fiber described above. SOLUTION: The core resin which is a polymethyl methacrylate resin and the sheath resin which is a polyvinyldene fluoride resin, satisfy the equation; 0.6>(n12-n22)0.5>0.45 when the refractive indices to a sodium D ray at 20 deg.C are respectively defined as n1 and n2. The core resin and sheath resin described above are supplied in the molten state to the composite spinning die, by which the optical fiber precursor having >=1 cores is manufactured. This precursor is stagnated in an atmosphere of >=60 deg.C, by which the optical fiber described above is constituted. As a result, the optical fiber of <=200 dB/km in the transmission loss measured by using a prescribed light source and >=120 MHz per 50 m in transmission band is obtained. |
