| 摘要 |
PURPOSE:To minimize a connection loss, unevenness in core diameter to clad outside diameter ratio and a scattering loss by detecting the outside diameter of an optical fiber and the diameter of the fiber core in a spinning process and controlling the amt. of glass fed to a crucible when the optical fiber is formed by a multiple crucible method. CONSTITUTION:Core material glass 1 and clad glass 2 are separately fed into double crucible 5 with feeders 3, 4. Glass 1 and glass 2 are melted by heating with furnace 9, and fiber 6 drawn out of opening 7 is wound round reel 14 through the detection section which is composed of photoreceptor 10 detecting reflection of laser beams emitted from light source 8 to fiber 6 and converting it into an electric signal and of computer 11 calculating the diameter of the fiber 6 core and the outside diameter of fiber 6 according to the signal and an electric signal from feeder control circuit 12. Circuit 12 adjusts the feed speeds of feeders 3, 4 so that the measured values are brought close to the desired values. The winding speed of reel 14 is also controlled at a rapid response speed with control circuit 13. |
